Initiation Of Plasma Exchange Research Articles

Variation in approaches to acute ANCA-associated vasculitis in Australia and New Zealand: rituximab, plasma exchange and glucocorticoids.

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare autoimmune disease which is managed by a range of specialities. There are limited data on treatment practices in Australia and New Zealand. To understand current patterns of acute AAV treatment in Australia and New Zealand. An online survey was conducted between July and October 2022 investigating physicians' views on the management of AAV, focusing on induction therapy. The survey contained questions pertaining to access to treatment and responses to clinical management scenarios. Eosinophilic granulomatosis with polyangiitis was not included. A chi-squared test of independence was performed for statistical analysis. From a total of 55 responses, plasma exchange was difficult to access for 44% of respondents, more so in rural centres, and they also had difficulty accessing infusion centres. New Zealand clinicians had more difficulty accessing rituximab, with only 44% reporting easy access compared with Australian clinicians (93%). With clinical management scenarios, there was variation in the dosing regimen of glucocorticoids and initiation of plasma exchange, with 42% of respondents prescribing a glucocorticoid regimen different from the standard of care, the 'reduced-dose' arm of the Plasma Exchange and Glucocorticoids for the Treatment of ANCA-Associated Vasculitis trial. The choice of cyclophosphamide or rituximab for induction therapy was based on patient characteristics and medical history. There is substantial variation in approaches to the acute management of AAV in Australia and New Zealand, including differences in resource availability. This variation in care demonstrates the need to implement current practice guidelines and institute contemporary monitoring of AAV management, to achieve best patient outcomes.

Determinants and Clinical Impact of Time to Plasma Exchange in Patients with Immune Thrombotic Thrombocytopenic Purpura

Background: Immune thrombotic thrombocytopenic purpura (iTTP) is a hematologic emergency characterized by severe acquired deficiency in the von Willebrand factor-cleaving metalloprotease ADAMTS13 and thrombotic microangiopathy, resulting in end organ damage and death if untreated. Plasma exchange (PLEX) is vital to the management of iTTP and has dramatically improved survival in this disorder since the 1980s. Guidelines recommend initiation of PLEX within 4-8 hours of presentation. However, despite the importance of prompt medical intervention, determinants of the total interval between symptom onset and initiation of PLEX (S2P) and time from presentation at the pheresis center to PLEX (door to PLEX, D2P) remain unclear. Further, the impact of S2P and D2P on clinical outcomes in iTTP have not been evaluated. Objective: Identify factors that predict S2P and D2P in patients with iTTP and assess the clinical impacts of S2P and D2P. Methods: We retrospectively evaluated cases in the Harvard TMA Research Collaborative (HaTRC), a curated single-center rare disease registry containing all consecutive iTTP cases seen between 2004 and 2022 at the three main Harvard teaching hospitals. We restricted our modeling analyses to patients who resided <350 km from downtown Boston. S2P was defined as time from patient-reported symptom onset until initiation of PLEX. D2P was defined as the time from the first complete blood count specimen drawn at a HaTRC hospital until the initiation of PLEX. Determinants of S2P and D2P were identified using multiple linear regression modeling of covariates derived from the HaTRC registry. The impacts of S2P and D2P on mortality and the composite of mortality and need for ICU admission were assessed using multiple logistic regression modeling. Results: A total of 155 unique patients comprising 243 separate iTTP episodes were recorded ( Figure 1). Analyses were limited to patients who resided <350 km from downtown Boston (n = 147 patients, 227 cases). The median (IQR) age was 40 (29-53) years. The cohort was 76% female, 63% of European ancestry, and 45% of episodes were relapse presentations. The median (IQR) S2P for the entire cohort was 4.3 (1.8-7.5) days, and the median D2P was 8.4 (5.0-16.0) hours. Excluding relapse presentations, crude S2P correlated with distance from Boston (Spearman r = 0.216, 95% CI: 0.029-0.389, p=0.02). After adjusting for age, sex, race, and LDH, we found that higher platelet count at presentation (β=0.039, 95% CI: 0.00047 to 0.077, p=0.047) and increased distance from Boston (β=0.030, 95% CI: 0.007 to 0.053, p=0.011) were associated with longer S2P, while patents with relapse presentations experienced a shorter S2P (β=-1.9, 95% CI: -3.7 to -0.12, p=0.037) ( Table 1). By contrast, increased D2P was significantly associated with male sex (β=7.43, 95% CI: 1.128 to 13.73, p=0.021) and higher platelet count (β=0.16, 95% CI: 0.41 to 0.27, p=0.008) but not with distance from Boston or relapse status. Longer S2P or D2P times were not associated with increased mortality, hospital LOS, or the composite of mortality and need for ICU admission; however, there was a non-significant trend towards increased LOS with relapse presentations (p=0.06) and longer D2P times (p=0.09). Conclusions: Our data suggest that iTTP patients who live farther from the hospital where they ultimately receive PLEX, those with higher platelet counts at presentation, and those presenting for the first time with iTTP experience a longer time to initiation of care. After hospital presentation, the determinants of a longer time to PLEX initiation shift to male sex and higher platelet count, both of which may be associated with lower clinical suspicion for iTTP and delayed diagnosis. These findings should be externally validated in an independent dataset.

Evaluating Risk Factors for Developing Allergic Reactions during Plasma Exchange using Fresh-frozen Plasma: A Single-center Retrospective Study.

Objective Allergic reactions are a severe complication of plasma exchange (PEx). Few reports have analyzed allergic reactions during PEx using fresh-frozen plasma (FFP) as a replacement solution. We therefore clarified the relationship between risk and exacerbation factors that lead to the onset of PEx-related allergic reactions, particularly PEx, using FFP, and examined whether or not allergic reactions were predictable. Methods This retrospective study included 88 consecutive patients who underwent PEx with FFP as a replacement solution at Kitasato University Hospital. The patients were grouped according to the presence of allergic reactions and compared. Data were analyzed using the χ2 test, Mann-Whitney U test, and a binomial logistic analysis. Statistical analyses were performed using EZR software program, version 1.54, with p <0.05 considered statistically significant. Results There were 44 allergic reaction cases. The average time to the onset of an allergic reactions was 63.5 (45-93) min. The allergic reaction-onset group had significantly higher average albumin (Alb) levels than did the non-allergic reaction-onset group. The binomial logistic analysis identified Alb levels as independent risk factors for allergic reactions. The receiver operating characteristic analysis identified an Alb level ≥3.4 g/dL as a risk factor for allergic reactions (area under the curve: 0.731; 95% confidence interval: 0.622-0.84). Conclusion Allergic reaction onset occurred approximately one hour after PEx initiation in the critical period. A serum Alb level ≥3.4 g/dL was identified as a risk factor for predicting allergic reactions. Patients with Alb levels ≥3.4 g/dL at the first PEx should be monitored for allergic reaction symptoms.

Delays in the Emergent Management of Patients with Immune-Mediated Thrombotic Thrombocytopenic Purpura: A Ten-Year Retrospective Study

Introduction: Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a hematologic emergency with up to 95% mortality if untreated. Emergent plasma exchange (PLEX) is the mainstay therapy in an acute episode. Due to the morbidity and mortality, the British Society of Haematology recommends initiation of PLEX within 4-8 hours, yet there is a limited data on real-world practice and if earlier initiation affects clinical outcomes. We sought to report timing of PLEX initiation in a tertiary hospital, assess for delays, and determine the variables that contribute to delays. Methods: The Parkland Health and Hospital System electronic medical record system was queried for ADAMTS13 activity over a ten-year period from 7/2011 to 7/2021, identifying 1,371 ordered tests, with 465 ordered in the emergency department, observation status, or inpatient setting. The first ADAMTS13 activity order was used as the initial time of suspected iTTP diagnosis. Time of line placement was obtained from documentation and imaging for internal jugular central venous catheters (CVCs). The time of PLEX initiation was derived from flowsheets maintained by the apheresis nursing staff. Delays in PLEX were defined as ≥8 hours from ADAMTS13 activity order to PLEX initiation (order-to-PLEX). Categorical variables were compared using the chi-square test, while continuous variables were compared using the Wilcox rank sum test. Results: Seventy-two patients were identified who were planned to undergo emergent PLEX. Two patients died before PLEX initiation-one patient had a CVC placed. Of the 70 patients receiving PLEX, 44% (n= 31) had an order-to-PLEX time ≥8 hours. The order-to-PLEX median (IQR) time (n=70) was 7.5 hours (4.7 - 20.3) with no significant difference between those with a history of iTTP versus those without (no history: 9.3h v history of iTTP: 6.4h, P = 0.10). Delays in PLEX were associated with eventual non-iTTP diagnoses (<8h: 26% v ≥8h: 52%, P = 0.025), higher platelet count (<8h: 18 v ≥8h: 33, P < 0.001), and the originating ADAMTS13 activity ordering department (P = 0.043). There were delays at each phase of PLEX initiation, including CVC placement (<8h: 2.8 hours v ≥8h: 20.7 hours) and PLEX initiation (<8h: 1.4 hours v ≥8h: 2.2). Discussion: We demonstrate that at a tertiary hospital only 54% of patients receive PLEX for suspected iTTP within 8 hours. Self-identified race or preferred language other than English were not associated with delays in PLEX. Line placement and PLEX initiation can both be significantly delayed and should be considered as potential benchmarks moving forward. Additionally, there is a knowledge gap since some ordering services waited for the ADAMTS13 activity to result prior to initiating emergent PLEX. Thus, we identify three areas for clinical improvement to expedite CVC placement and timely initiation of PLEX for patients with suspected iTTP: 1) improvement in education and workflows to emphasize the emergent nature of iTTP, 2) codifying agreements with procedure services to expedite CVC placement, and 3) arranging apheresis coverage for immediate PLEX. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

A Real-World Analysis of Acquired Thrombotic Thrombocytopenic Purpura: Comparing Clinical Outcomes of Early Versus Late Responders to Plasma Exchange

INTRODUCTION: Acquired thrombotic thrombocytopenic purpura (TTP) is a rapidly fatal thrombotic microangiopathy mediated by autoantibodies targeting ADAMTS-13. The main pillars of acquired TTP management include therapeutic plasma exchange (PLEX) and immunosuppression with glucocorticoids and rituximab. PLEX is initiated in all patients with a presumptive clinical/confirmed diagnosis of TTP and is continued until platelet count recovery. The platelet response to PLEX is quite variable, with some patients having rapid recovery (early responders [ERs]) within 4-7 days, and others requiring a longer duration (late responders [LRs]) of PLEX. Although rapid platelet count recovery is reassuring to the treating physician, it is unclear whether there is a significant difference in outcomes between ERs and LRs to PLEX. We performed a single-center retrospective study of survival outcomes of ERs vs those of LRs with acquired TTP. METHODS: We performed a retrospective analysis of adult patients (≥18 years old) with acquired TTP who were treated at our institution between January 1, 2005, and May 1, 2020. Baseline demographic and clinical data and laboratory values at the time of diagnosis were collected. Patients were ERs if platelet recovery (platelet count >150,000/µL for 2 consecutive days) occurred within 7 days of starting PLEX, whereas LRs had delayed platelet recovery (≥7 days) after initiation of PLEX. Refractory disease was defined as recurrent thrombocytopenia (platelet count <150,000/µL) following an initial response between days 1 and 30 after last PLEX. Relapses were defined as thrombocytopenia and elevated LDH occurring >30 days after last PLEX. We analyzed survival outcomes and the relapse risk in ERs versus LRs. RESULTS: A total of 61 patients fulfilled the diagnostic criteria for acquired TTP (ER = 34 patients, LR = 27 patients). Patient demographics, laboratory studies, and treatment details are shown in Table 1. The mean age of ER and LR patients was 45 and 38 years, respectively. About 56% of patients in each group identified as Black. About 18% of ERs and 9% of LRs had a diagnosis of HIV. No statistically significant difference was noted in the baseline laboratory findings of the two groups. Involvement of ≥2 affected organ systems was seen in 79% of ERs and 93% of LRs (p=0.2757). All LRs (100%) and 88% of ERs had severe TTP at presentation (ADAMTS-13 level ≤10). The mean number of PLEX was 6.11 and 24.96 in ERs and LRs (p<0.0001), respectively. The mean number of PLEX to platelet recovery was 4.27 and 19.27 (p<0.0001). Glucocorticoids were given to 97% of ERs and 100% of LRs. First-line rituximab was given to 52% (n=14) of LRs, versus only 9% (n=3) of ERs (p=0.0004). About 15% of LRs went on to receive additional immunosuppressive agents, whereas no ERs did so (p=0.0336). The relapse rate among ERs and LRs was 55.56% and 44.44%, respectively (p > 0.9999). The 30-day mortality rate was 6% in ERs and 0% in LRs. Cardiovascular diseases were the common cause of early deaths. Overall survival (OS) at 6 months was 79% in ERs and 96% in LRs (p=0.0665). The OS at 1 year was 74% in ERs and 96% in LRs (p=0.03). The 2-year OS was available for 24 ER patients (83%) and LR 17 patients (89%) (p>0.9999). Among the 19 patients who received front-line rituximab, the OS at 1 year was 100%. CONCLUSIONS: More LRs than ERs received rituximab and glucocorticoids for immunosuppression as first-line therapy. LRs were found to have a statistically significant greater OS at 1 year. ERs were less likely to receive adequate immunosuppression than LRs. This may indicate that the time to response to PLEX should not be used as a surrogate for risk of relapse. Immunosuppression is the cornerstone of the management of acquired TTP, and first-line use of rituximab is critical in the reducing relapse rate and improving OS. Larger studies in the prospective setting are needed to evaluate the impact of duration of PLEX on OS. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Emergent Large-Bore Central Venous Catheter Placement in Severely Thrombocytopenic Patients with Suspected Immune-Mediated Thrombotic Thrombocytopenic Purpura Is Safe and Effective

Introduction: Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a progressive and nearly uniformly fatal disease if not suspected and managed with plasma exchange (PLEX). Initiation of PLEX requires placement of a large-bore central venous catheter (CVC) in a patient with severe thrombocytopenia where platelet transfusion is contraindicated except in the setting of life-threatening hemorrhage. We sought to determine the safety and complication rates of large-bore CVC placement in patients with suspected iTTP. Methods: The Parkland Health and Hospital System electronic medical record system was queried for ADAMTS13 labs from 7/2011 to 7/2021, identifying 1,371 ordered tests with 465 being ordered in the emergency department, observation, or inpatient setting. Sixty-eight patients had a large-bore CVC placed for PLEX with suspicion for iTTP. Characteristics of providers performing CVC placement were obtained via chart review. Records were reviewed for complications, including death, infection, thrombosis, bleeding, pneumothorax, or pressure ulcers. Minor bleeding complications were procedure site hematomas and self-limited episodes of bleeding requiring manual pressure. The only major complication was a hematoma that required intubation for airway protection. Categorical variables were compared using the chi-square test, while continuous variables were compared using the Wilcox rank sum test. Results: Of the 68 patients, the majority were Black or Hispanic (84%). Central venous catheter placement was most often performed by General Surgery (68%) followed by the Medical Intensive Care Unit (MICU; 12%), Emergency Medicine (7%), and Nephrology (7%). Surgery and Emergency Medicine placed significantly more catheters in patients who ultimately had iTTP (P = 0.03). Resident physicians placed the majority of CVCs (79%) with no prophylactic blood products used in over 90% of cases. There was a 12% (8 out of 68) complication rate predominantly related to bleeding (n=7), although one patient had a pressure ulcer due to a lack of mobility after a femoral vein CVC placement. There was only one severe complication with the development of a rapidly expanding hematoma during an internal jugular (IJ) line placement causing airway compromise and requiring intubation. There were no differences in complication rates between line placement by General Surgery versus other services (P = 0.91) or with prophylactic platelet (P = 0.81), cryoprecipitate (P = 0.59), or FFP (P = 0.70) transfusions. A significant association was observed between the number of line attempts (median [IQR]) and complications (2 [2-4] v patients without complications: 1 [1-1], P < 0.001). In patients with iTTP, pre-procedural coagulation parameters had significantly lower platelets, lower INR, lower PT, and higher fibrinogen, suggesting a level of coagulopathy and/or disseminated intravascular coagulation in patients who were ultimately not found to have iTTP. Discussion: In a tertiary hospital, there was only one severe complication of large-bore CVC placement was observed in a cohort of 68 patients-most of whom had severe thrombocytopenia and did not receive prophylactic platelet or cryoprecipitate transfusions. Furthermore, resident physicians placed 79% of these CVCs without a significant increase in complication rate. Given that iTTP is a severe and progressive disease requiring emergent intervention, our findings suggest that CVC insertion for PLEX should not be delayed due to concerns regarding thrombocytopenia or bleeding complications. Most complications were minor bleeding or hematomas that resolved with pressure and observation. No significant difference in the rate of complications was observed when comparing surgical and non-surgical services. Conversely, there was an association between the number of CVC placement attempts and complications, suggesting that the line should be placed by whomever is qualified and available to expedite treatment. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Diagnostic uncertainty presented barriers to the timely management of acute thrombotic thrombocytopenic purpura in the United Kingdom between 2014 and 2019

BackgroundAcute thrombotic thrombocytopenic purpura (TTP) is a life‐threatening emergency and plasma exchange (PEX) is the initial treatment shown to reduce acute mortality. ObjectivesTo compare current practice in the United Kingdom (UK) against the standards set out in the 2012 British Society of Haematology guideline, and to better understand the issues affecting prompt initiation of PEX. Patients/MethodsThe trainee research network HaemSTAR conducted a retrospective nationwide review of adults presenting to UK hospitals with a first episode of acute TTP. ResultsData on 148 patients treated at 80 UK hospitals between 2014 and 2019 demonstrated that 64.8% of patients received PEX within 24 h. Diagnostic uncertainty was the most commonly cited reason for delayed treatment. Conversely, a shorter time to PEX occurred in patients who had red cell fragments or severe thrombocytopenia identified on their first complete blood count. Availability of on‐site PEX was associated with a greater proportion of patients receiving PEX within 8 h compared to patients transferred, but by 24 h there was no difference between the two groups and two‐thirds of all patients had received their first PEX. The mortality rate for patients that received PEX was 9.2%, with 27.8% of deaths linked to delayed treatment initiation. ConclusionsThis is the first multi‐center evaluation of treatment delays in acute TTP and it will inform targeted pathways to improve prompt access to life‐saving intervention.

A Young Woman with Anemia and Thrombocytopenia

&lt;p&gt;本文描述一位32歲女性病患，罹患全身性紅斑性狼瘡已有11年，規則於門診追蹤，因發燒、關節痛、胸痛，實驗室檢查發現貧血、血小板低下、補體（C3）低下、高效價之抗雙股去氧核糖核酸抗體（anti-dsDNA &gt; 379 IU／mL）、尿液呈現蛋白尿，初步診斷懷疑全身性紅斑性狼瘡復發。靜脈注射高劑量methylprednisolone七天，血小板仍偏低，治療反應差。本個案實驗室檢查顯示溶血性貧血、血小板低下、週邊血液抹片顯示碎裂紅血球，確定微血管性溶血性貧血證據，且血液中ADAMTS 13嚴重缺乏其血中活性為0%，因此診斷為血栓性血小板低下紫斑症。緊急接受血漿置換術，同時持續高劑量類固醇與靜脈注射Rituximab治療，因而血小板上升、乳酸脫氫脢大幅下降、貧血改善，達到治療的成效。全身性紅斑性狼瘡同時出現血栓性血小板低下紫斑症，經緊急啟動血漿置換，會降低病人的死亡率。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;A 32-year-old female patient in this study, who suffered from systemic lupus erythematosus (SLE) for 11 years. Upon a regular rheumatology outpatient follow-up, she presented not only with fever,arthralgia and chest pain, but also with anemia, low platelets, low complement (C3), and high titer anti-double-strand deoxyribonucleic acid antibody (anti-dsDNA &gt; 379 IU/mL) on laboratory test report,as well as proteinuria on urinalysis. Accordingly, her condition was suspected to be a relapse of SLE. Unfortunately, after treatment with high-dose intravenous methylprednisolone, the response was poor with persistent low platelet level. Besides, hemolytic anemia and thrombocytopenia were noted and peripheral blood smear examination also showed fragmented red blood cells, supporting the diagnosis of microangiopathic hemolytic anemia. Moreover, there was severe ADAMTS13 deficiency in the blood, even with 0% of activity. Therefore, the patient was finally diagnosed with thrombotic thrombocytopenic purpura and then received urgent plasmapheresis in combination with high-dose glucocorticoid and of intravenous rituximab treatment. After the treatment, the platelet level increased, lactate dehydrogenase level remarkably decreased, and anemia gradually improved. Taken together, urgent initiation of plasma exchange together with glucocorticoid and rituximab treatment for SLE patient with thrombotic thrombocytopenic purpura could lower the mortality rate.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;

Clinical experience of plasmapheresis for neuromyelitis optica patients in Mexico

BackgroundNeuromyelitis optica spectrum disorders (NMOSDs) are a group of chronic immune-mediated demyelinating diseases of the central nervous system. Their pathophysiology dependent on humoral mediated responses caused by autoreactive IgG antibodies against aquaporin-4 water channels (AQP4-IgG) or myelin oligodendrocyte glycoprotein (MOG-IgG). Plasma exchange (PLEX) has proved to be a beneficial therapy in patients with severe relapses. We present the largest series of Latin American patients treated with PLEX for acute NMOSDs relapses. MethodsA retrospective study was conducted. Selection included patients diagnosed with NMOSDs who received PLEX between 2010-2019, irrespective of their AQP4-IgG serostatus. All patients received 5 grams of IV methylprednisolone. PLEX therapy could be initiated simultaneously or after IV steroids. Baseline and post-PLEX therapy Expanded Disability Status Scale (EDSS) was measured to identify acute response to therapy. Comparison between responders and non-responders was also conducted. Subgroup analysis stratified response by serostatus, type of clinical relapse and time to PLEX. ResultsA total of 89 patients were included. Mean age at onset was 38 ± 12.97 years. 49 (55.1%) patients were AQP4-IgG seropositive. Most patients had unilateral optic neuritis (34.8%) or longitudinally extensive transverse myelitis (33.7%). Mean time from onset to PLEX initiation was 20.9 ± 18.1 days. Response rate was 39.3% and mean decline in EDSS was 0.7 ± 0.9 (p <0.001). Decline in EDSS and response rate were independent of serostatus, type of clinical relapse or time to PLEX initiation. ConclusionPLEX appears to be an effective therapy for NMOSDs relapses even in limited resources setting where treatment initiation may be delayed. The benefit seems to be independent of the type of clinical relapse and AQP4 IgG serostatus.

Real-world experience with caplacizumab in the management of acute TTP

The cornerstone of life-saving therapy in immune-mediated thrombotic thrombocytopenic purpura (iTTP) has been plasma exchange (PEX) combined with immunomodulatory strategies. Caplacizumab, a novel anti–von Willebrand factor nanobody trialed in 2 multicenter randomized controlled trials (RCTs) leading to European Union and US Food and Drug Administration approval, has been available in the United Kingdom (UK) through a patient access scheme. Data were collected retrospectively from 2018 to 2020 for 85 patients (4 children) receiving caplacizumab from 22 UK hospitals. Patient characteristics and outcomes in the real-world clinical setting were compared with caplacizumab trial end points and historical outcomes in the precaplacizumab era. Eighty-four of 85 patients received steroid and rituximab alongside PEX; 26% required intubation. Median time to platelet count normalization (3 days), duration of PEX (7 days), and hospital stay (12 days) were comparable with RCT data. Median duration of PEX and time from PEX initiation to platelet count normalization were favorable compared with historical outcomes (P < .05). Thrombotic thrombocytopenic purpura (TTP) recurred in 5 of 85 patients; all had persistent ADAMTS13 activity < 5 IU/dL. Of 31 adverse events in 26 patients, 17 of 31 (55%) were bleeding episodes, and 5 of 31 (16%) were thrombotic events (2 unrelated to caplacizumab); mortality was 6% (5/85), with no deaths attributed to caplacizumab. In 4 of 5 deaths, caplacizumab was introduced >48 hours after PEX initiation (3-21 days). This real-world evidence represents the first and largest series of TTP patients, including pediatric patients, receiving caplacizumab outside of clinical trials. Representative of true clinical practice, the findings provide valuable information for clinicians treating TTP globally.

Chemotherapy-induced myasthenic crisis in thymoma treated with primary chemotherapy with curative intent on mechanical ventilation: a case report and review of\xa0the literature

BackgroundThymoma is an uncommon cancer often associated with myasthenia gravis, an autoimmune disorder of the neuromuscular junction characterized by muscular fatigability. In patients with advanced nonmetastatic thymoma, primary chemotherapy may be required to induce tumor shrinkage and to achieve radical resection. Cancer chemotherapy has been anecdotally reported as a trigger factor for worsening of myasthenia gravis in thymic epithelial cancers. The study of uncommon cases of chemotherapy-related myasthenic crisis is warranted to gain knowledge of clinical situations requiring intensive care support in the case of life-threatening respiratory failure.Case presentationWe report a case of an 18-year-old Caucasian woman with advanced Masaoka-Koga stage III type B2 thymoma and myasthenia gravis on treatment with pyridostigmine, steroids and intravenous immunoglobulins, who developed a myasthenic crisis 2 hours after initiation of cyclophosphamide/doxorubicin/cisplatin primary chemotherapy. Because of severe acute respiratory failure, emergency tracheal intubation, mechanical ventilation, and temporary (2 hours) discontinuation of chemotherapy were needed. Considering the curative intent of the multimodal therapeutic program, we elected to resume primary chemotherapy administration while the patient remained on mechanical ventilation. After 24 hours, the recovery of adequate respiratory function allowed successful weaning from respiratory support, and no further adverse events occurred. After 3 weeks, upon plasma exchange initiation with amelioration of myasthenic symptoms, a second course of chemotherapy was given, and in week 6, having documented partial tumor remission, the patient underwent radical surgery (R0) and then consolidation radiation therapy with 50.4 Gy in 28 fractions in weeks 15–20.ConclusionsThis case report, together with the only four available in a review of the literature, highlights that chemotherapy may carry the risk of myasthenic crisis in patients affected by thymoma and myasthenia gravis. To our knowledge, this is the first reported case of chemotherapy continuation on mechanical ventilation in a patient with chemotherapy-induced myasthenic crisis requiring tracheal intubation. The lesson learned from the present case is that, in selected cases of advanced thymoma, the paradoxical worsening of myasthenia gravis during chemotherapy should not be considered an absolute contraindication for the continuation of primary chemotherapy with curative intent.

Timing of plasma exchange for neuromyelitis optica spectrum disorders: A meta-analysis

BackgroundNeuromyelitis optica spectrum disorders (NMOSDs) are autoimmune astrocytopathies with predominant involvement of the optic nerves and spinal cord. The current management is high-dose intravenous methylprednisolone, followed by apheresis therapy if it fails. We aimed to investigate plasma exchange (PE) benefits in corticosteroid-refractory NMOSDs. MethodsFrom Embase, PubMed, Cochrane, Web of Science, and Clinical Trials, we identified PE-based studies published between Jan 2007 and Dec 2019. We pooled the information of these studies in a binomial meta-analysis. We investigated the factors affecting the efficacy of PE and its adverse events. The effectiveness of PE was assessed using the Expanded Disability Status Scale (EDSS). The timing of PE initiation was assessed using Spearman correlation analysis. ResultsWe included 561 records and identified 8 observational studies, including 228 NMOSD patients. The mean time to the initiation of PE was 11 days, and the average volume of each exchange was 1.5–2 L. PE treatment reduced the mean EDSS score by −1.04 (95% CI, −1.44 to −0.64). The initiation time of PE significantly affected the outcome (EDSS reduction) (P = 0.01; 95% CI, −1.30 to 0.28). In the ≤ 7-day and 8–23-day groups, the mean EDSS decreased by 0.64 (95% CI, −0.93 to −0.34) and 1.41 (95% CI, −1.79 to −1.02), respectively. In addition, PE showed the same efficacy for alleviating the symptoms of NMOSDs, regardless of the day between 8 to 23 days on which it was performed (P = 0.29). Thirty-five (20.8%) of the 168 patients had adverse events. ConclusionPE can ameliorate severe NMOSDs. PE effectiveness was associated with the duration between disease and the initiation of PE, and the optimal timing for PE initiation is 8 to 23 days after the onset of the disease.

Factors Influencing Time from Initial Presentation to Start of Plasma Exchange (PEX) in Patients with Acute Thrombotic Thrombocytopenic Purpura (TTP)

Background: Acute Thrombotic Thrombocytopenic Purpura (TTP) is a life-threatening medical emergency and plasma exchange (PEX) is the only treatment shown to significantly impact acute mortality (Rock et al, N Engl J Med 1991). Diagnosis can be challenging and therein arrangements for PEX must be made, with most centers in the United Kingdom (UK) having to co-ordinate transfer to a tertiary site. To understand issues affecting practice the trainee research network HaemSTAR conducted a retrospective nationwide review of patients presenting to UK hospitals with TTP against British Society of Haematology clinical guidelines (Scully et al, B J Haem 2012). Analysis was conducted on the time from hospital presentation to initiation of treatment and impact on patient outcomes. Method: Adults ≥18 years presenting to hospital between 1st June 2014 and 1st June 2019 with first episode acute TTP and ADAMTS13 level &amp;lt;10% were identified by local clinicians. Anonymized data of baseline characteristics and treatment times was submitted via an online secure server. Time to PEX was defined as time from receipt of the first full blood count sample in the laboratory to time of plasma release for PEX from blood bank. Where patients were transferred between sites data was linked retrospectively. Results: Data on 148 patients treated at 80 UK hospitals was used for analysis (demographics table 1). 142 patients (96%) received PEX, 67 (47%) at site of presentation and 75 (53%) after hospital transfer. 6 patients died before receiving PEX. 37 patients (25%) received PEX within 8 hrs of hospital presentation, 91 patients (61%) within 24 hrs. 33 patients (22%) commenced PEX more than 48 hrs from presentation. The overall median time to PEX from initial presentation was 15 hours (95% CI 11.3-18.7). Availability of on-site PEX was associated with earlier treatment initiation with median time to PEX for those treated on site 10 hrs (95% CI 7.7-12.3) vs. 21 hrs (95% CI 16.8-25.2) for patients transferred. A blood film comment of red cell fragments significantly impacted time to treatment: in 24 cases with no fragments documented median time to PEX was 110 hrs (95% CI 39-181) vs. 10 hrs (95% CI 8.5-11.5) in cases where fragments were reported (fig 1). On univariate and multivariate analysis age &amp;lt;60 years, hemoglobin (Hb) &amp;lt;100 g/L, presence of fragments, PEX available on-site and admissions occurring after May 2017 were significant predictors for PEX initiation within 8 hrs. PEX within 24 hrs was associated with age &amp;lt;60 years, platelet count &amp;lt;30 x 109/L, Hb &amp;lt;100 g/L and presence of fragments only. The presence of cardiac and/or central nervous system (CNS) involvement was not predictive of time to initiation of PEX (table 1). 96 patients (62%) received steroids within 24 hrs of presentation, 98 of 128 patients with cardiac/CNS involvement (77%) received rituximab within 48 hrs and 12 patients (8%) received platelet transfusion in the absence of major bleeding. 19 patients (12%) died within 30 days of presentation (median time to death 10 days, range 0-23). In 7 of these cases (37%) a delay &amp;gt;24 hrs from presentation to diagnosis was reported despite presence of fragments in 4 cases. Mortality did not correlate with availability of on-site PEX. Discussion: This is the first multi-center record of time to treatment from initial presentation of acute TTP. Results comply with guidance for rapid initiation of PEX with 61% patients commencing within 24 hrs of presentation and, from June 2017, 34% of patients initiating PEX within 8 hrs. The recent increase in early PEX initiation correlates with initiatives to improve treatment pathway efficiency following diagnosis of TTP. Early use of steroids and rituximab correlated with earlier use of PEX indicating where timely diagnosis was made there was good compliance with guidelines. Inappropriate use of platelets appeared attributable to misdiagnosis. Older patients, those with higher platelet counts and Hb and absence of red cell fragments on film report were more likely to experience prolonged time to initiation of PEX. This does not appear related to PEX access, but most likely the difficulty of making TTP diagnosis in this cohort. That 22% of patients initiated PEX over 48 hrs from admission indicates the issue is relatively common and with several deaths occurring in this group we suggest initiatives to increase early diagnosis should be prioritised. Full contributor list: http://haemstar.org/flash-mob-audit-2019/ Disclosures McCulloch: Sanofi: Research Funding. Nicolson:Principia Biopharma: Research Funding; Novartis: Research Funding; Rigel pharmaceuticals: Research Funding; Bayer: Honoraria. Shaw:Octapharma: Research Funding. Scully:Alexion: Consultancy, Speakers Bureau; Takeda: Consultancy, Speakers Bureau; Sanofi: Consultancy, Speakers Bureau; Takeda: Speakers Bureau; Ablynx/Sanofi: Consultancy, Other: Advisory Board, Speakers Bureau; Shire/Takeda: Other: Advisory Board, Research Funding, Speakers Bureau; Novartis: Other: Advisory Board, Speakers Bureau.

SAT-451 PLASMA EXCHANGE IN YELLOW PHOSPHORUS POISONING-A SINGLE CENTRE STUDY

Yellow phosphorus(YP) is one of the causes of rodenticide poison in developing countries especially India, due to easy availability, cheap cost & easy accessibility. Liver transplantation is the treatment of choice in patients with fulminant hepatic failure(FHF). Here we present our experience in dealing this poison with plasma exchange(PE) as the modality of treatment when liver transplantation is not an easily available option. In this prospective study, all patients of YP poisoning who had fulminant hepatic failure requiring plasma exchange were taken into the study. The study period was from January 2017 to June 2019. Clinical presentation, co-morbidities, poison form & amount, day of hospitalisation, day of initiation of plasma exchange, hepatic encephalopathy grade & baseline characteristics were noted. FHF was defined according to O'Grady/King's College criteria. History of ethanol consumption, prior liver disease documented. Laboratory data including Liver function test(LFT), Renal function test, coagulation parameters were noted serially before & after plasma exchange. Outcomes were documented as recovered or not recovered. Continuous variables were expressed as mean± Standard deviation or median and range according to test for normal distribution by using Shapiro-Wilk test. Friedman test was applied to check the continuous parameters at three different point of time. Independent-t test was used for statistical analysis where-ever required. A p-value of < 0.05 was considered statistically significant. A total of 10 patients were included in the study. 6 were males(60%) & 4 females(40%). Median age was 24.5 yrs. Seven patients(70%) recovered completely, 3 patients(30%) didn't recover. Among those 3 patients, one was referred for liver transplantation, one expired and one more had persistent liver dysfunction. 90% of patients had deliberate YP consumption, especially in paste form(90%). Among 7 patients who consumed < 20 gm of YP, 6 recovered(85.7%); whereas only one recovered(14.3%) among the rest who consumed ≥ 20 gm. 40% of patients received 2 sessions of PE, 30% received 5 sessions, 20% received 3 sessions and remaining 10% received 4 sessions. Mean sessions of PE was 3.5(2-5). For recovery, the mean day of hospitalization was 3.57 days(p=0.019) and for initiation of PE was 4.86 days(p=0.016) after consumption of YP. Peak median total bilirubin (mg/dl) prior to PE was 9.29 and decrease after PE was 2.76(p=0.005). Mean SGOT(IU/L) decreased from 819.8 to 61.4(p=0.005); SGPT(IU/L) from 457.8 to 65.8(p=0.005) ;INR from 3.24 to 1.4(p=0.008); PT(s) declined from 79.38 to 21.48(p=0.013);APTT(s) from 56.44 to 31.87 (p=0.007) post PE. Diabetes Mellitus & Hypertension didn't have any effect on the outcome. Out of 3 patients who had history of ethanol consumption, 2 recovered. The outcome of the patient depends on the amount of YP consumed; the day of hospitalization & initiation of PE from the day of YP consumption. Earlier the hospitalization &earlier the PE; more are the chances of recovery. Our experience suggests that PE is an effective approach for YP poisoning with 70% survival rate with improvement in LFT & coagulation parameters.

Describing the Point Prevalence and Characteristics of Venous Thromboembolism in Patients with Thrombotic Thrombocytopenic Purpura

Background: Thrombotic thrombocytopenic purpura (TTP) presents with microangiopathic hemolytic anemia, thrombocytopenia and microvascular thrombosis. Arterial thromboembolic events are relatively common and well-described in these patients. However, the literature describing venous thromboembolism (VTE) in this patient population is scarce and outdated. We hypothesize that patients with TTP are at greater risk for VTE due to the use of central venous catheters and use of solvent-detergent plasma (SDP) for plasma exchange (PLEX). Methods: Eligible patients from a single tertiary care centre were identified through apheresis records, and a retrospective chart review was conducted. The criteria for TTP diagnosis included the presence of accepted clinical/laboratory criteria and ADAMTS13 activity &lt;10%. We considered the diagnosis of VTE if any of the following were present: pulmonary embolism (PE), deep vein thrombosis (DVT) or superficial vein thrombosis (SVT). Data were analyzed using simple descriptive statistics. Institutional research ethics board approval was obtained. Results: We identified 77 consecutive patients with 123 episodes of TTP between January 1, 2008 and December 31, 2018. 51 patients (66%) were female, and 74 (96%) had immune TTP. Standard of care was daily PLEX and high-dose steroids, while rituximab was used for relapsed/refractory disease. In addition, 6 patients received caplacizumab. 13 of the 77 patients (17%) experienced a VTE (14 events: 6 PE, 5 DVT, 3 SVT), all of which were acute and associated with admission for either first presentation or relapse of TTP. None of the VTEs were catheter related. 8/13 patients were female, and all had immune TTP. Median age at diagnosis of VTE was 45 years (IQR: 36.0-56.5 years). 10/14 events were symptomatic; diagnosis was confirmed a median of 1.5 days after VTE symptom onset (IQR: 1-3 days). All patients were treated with PLEX, receiving a median of 17 exchanges (IQR: 10-23 exchanges). In addition, 13/14 TTP episodes were treated with corticosteroids, 9 with rituximab, and no patients received caplacizumab. 8 patients experienced a VTE while receiving daily PLEX; the majority (6/8) were being exchanged with SDP. VTE was diagnosed a median of 13.5 days after initiation of PLEX (IQR: 9.2-23.5 days). At TTP presentation, median platelet count was 11 x 109/L (IQR: 7-16 x 109/L), and median LDH was 894 U/L (IQR: 508-1272 U/L). At VTE diagnosis, the median platelet and LDH levels were 170 x 109/L (IQR: 126-248 x 109/L), and 232 U/L (IQR: 176-254 U/L) respectively. No patients had D-dimer testing at VTE symptom onset or diagnosis. Of the 6 patients with PE, 3 had elevated troponin levels (&gt;0.040 ug/L) at VTE diagnosis. In terms of VTE risk factors, median BMI was 30.0 (IQR: 28.7-32.1); the majority of patients (7/13) were obese (BMI&gt;30). 4/13 patients were active cigarette smokers. No patients had a history of lupus or antiphospholipid antibody syndrome. 2 patients had a past history of VTE, one was associated with a prior TTP episode. Most VTEs (8/14) occurred while patients were not on any pharmacologic thromboprophylaxis. For the remaining patients, dalteparin (3), ASA (2) and rivaroxaban (1) were used. VTE events were treated with direct oral anticoagulants (DOACs) including rivaroxaban and apixaban, in 10 cases. 7 of these patients were started on a DOAC after a brief initial period of low molecular weight or unfractionated heparin, 3 patients were given DOAC as upfront therapy. 4 cases were treated with warfarin (3 bridged with heparin and 1 following rivaroxaban). One distal DVT was not treated. None of the VTEs were fatal. Discussion: The point prevalence of VTE was 17% over one decade amongst patients with TTP; this is higher than previously reported in the literature. Our data also suggests that TTP patients may be at greater risk for VTE compared to general hospitalized medical patients. The majority of affected patients on PLEX were receiving SDP at VTE diagnosis. SDP contains reduced levels of proteins C and S and may have a pro-thrombotic effect. Almost all VTEs occurred after platelet recovery and normalization of hemolytic markers, suggesting a different pathophysiology than arterial thrombosis in this setting. VTE thromboprophylaxis was uncommon since it was often held due to thrombocytopenia and not resumed upon platelet recovery. Our findings suggest the need to implement VTE thromboprophylaxis earlier in patients admitted with TTP. Disclosures Sholzberg: Novartis: Honoraria; Amgen: Honoraria, Research Funding. Pavenski:Ablynx: Honoraria, Research Funding; Alexion: Honoraria, Research Funding; Shire: Honoraria; Octapharma: Research Funding; Bioverativ: Research Funding.

Validation of the Plasmic Score for Predicting ADAMTS13 Activity < 10% in Patients Admitted to Hospitals in Alberta with Suspected Thrombotic Thrombocytopenic Purpura

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening thrombotic microangiopathy (TMA), characterized by widespread intravascular thrombosis. Diagnosis of TTP is confirmed by a deficiency in ADAMTS13. However, given the urgency of prompt diagnosis and delayed turnaround time of ADAMTS13 assay in most labs, initial diagnosis is based on clinical acumen. Suspected TTP is empirically treated with plasma exchange (PLEX), which, while beneficial in TTP, may delay appropriate treatment for similar disorders. The PLASMIC score was developed by Bendapudi et al. (Lancet Hematology 2017) to utilize clinical signs and investigations to predict which patients had an ADAMTS13 score &lt; 10%, and therefore TTP, who require PLEX. Validation studies have shown a very high sensitivity (90-98%) and high specificity (46-92%), although these studies included an enriched population with available ADAMTS13 assay results (Jajosky et al. Transfusion and Apheresis Science, 2017, Li et al. Journal of Thrombosis and Hemostasis 2018). The purpose of this study is to validate the PLASMIC score using a Canadian population of suspected TTP regardless if ADAMTS13 was ordered, and compare it to clinical gestalt. This is a retrospective cohort study of all adults aged 18 years or older who presented or were transferred to any of the two apheresis centres in Alberta, Canada with a suspected diagnosis of TTP from January 1, 2008 - December 31, 2018. A confirmed diagnosis of TTP was defined as an ADAMTS13 level prior to PLEX &lt; 10%, or ADAMTS13 level between 10-20% if drawn after plasma infusion or PLEX. ADAMTS13 testing was done in accordance with the procedures at these institutions. The PLASMIC score was used to stratify patients into low (0-4), intermediate (5) and high (6-7) risk of TTP (Table 1). Descriptive analyses was performed to examine the proportion of patients with low-, intermediate-, and high-risk PLASMIC score who had ADAMTS13 testing done and who received PLEX. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PLASMIC score were calculated. Two PLASMIC score cutoffs were used for the analysis, 1) high risk vs low to intermediate risk, and 2) intermediate to high risk vs low risk. Receiver operator curve (ROC) analysis was used to test the association between severe ADAMTS13 deficiency and the PLASMIC score. PLASMIC scores were also compared to clinical gestalt, defined as initiation of PLEX within 48 hours of presentation. The C statistic was calculated from the area under the ROC and compared using the Z-test. As some patients who may have died from TTP did not have ADAMTS13 level sent, sensitivity analysis was performed to assess the ROC curve for the PLASMIC score in detecting both definite and probable TTP. A P-value of &lt;0.05 was considered statistically significant. Of the 162 cases of suspected TTP, 61 (38%) had severe ADAMTS13 &lt;10%. ADAMTS13 was sent prior to plasma exchange in 103 (64%) cases and shortly after PLEX initiation in 15 (9%). Using a high-risk PLASMIC score cut-off (6-7) vs low to intermediate-risk score (0-5), the sensitivity was 83.6%, specificity 67.3%, PPV 60.7% and NPV 87.2%. In contrast, using a cut-off of medium to high-risk PLASMIC score (5-7) vs low-risk score (0-4), the sensitivity improved to 96.7%, whereas the specificity was reduced to 30.7% (PPV 45.7% and NPV 93.9%). The C-statistics were 0.75 (95% CI 0.69-0.82) and 0.64 (95% CI 0.59-0.69) using the high PLASMIC score and medium-high PLASMIC score cut-offs, respectively (Figure 1). In contrast to PLASMIC score-based risk stratification, clinical gestalt has a comparable sensitivity of 83.6%, but a much lower specificity of 38.9%. There was very low correlation between PLASMIC score and clinical gestalt (kappa 0.0883 (95% CI -0.03-0.21). In our cohort, a high-risk PLASMIC score successfully predicted patients with severe ADAMTS13 deficiency in a Canadian TMA population, with similar sensitivity and improved specificity compared to clinical gestalt. Integration of this scoring system into institutional clinical pathways should be considered to supplement clinician judgment and reduce costs. Disclosures No relevant conflicts of interest to declare.

A pilot study comparing treatments for severe attacks of neuromyelitis optica spectrum disorders: Intravenous methylprednisolone (IVMP) with add-on plasma exchange (PLEX) versus simultaneous ivmp and PLEX

Background: Our previous retrospective study demonstrated that NMOSD patients with an acute attack who did not respond to IVMP alone, however, showed further significant improvement after treatment with PLEX at 6 month-follow-up. Objective: To compare the efficacy between treatments with intravenous methylprednisolone (IVMP) with subsequent add-on plasma exchange (PLEX) and a combination of simultaneous IVMP and PLEX in neuromyelitis optica spectrum disorders (NMOSD) patients with a severe acute attack.Method: We conducted a prospective, randomized, controlled, pilot study of the treatments for a severe acute attack in NMOSD patients. Results: There were eleven AQP4-positive NMOSD patients in the study. One received only IVMP, five received IVMP with subsequent add-on PLEX treatment, and the other five received simultaneous IVMP and PLEX treatment. The attacks comprised myelitis (57.1%) and optic neuritis (42.9%). Both treatments with IVMP followed by subsequent add-on PLEX when needed (not-respond to IVMP treatment) and a combination treatment of simultaneous IVMP+PLEX from the outset showed clinical improvement measured by EDSS at 6 months follow-up, compared to those at the attacks (p-value = 0.07 in IVMP add-on PLEX group and p-value = 0.05 in IVMP+PLEX group), respectively. Although, a trend of a better outcome stratified by EDSS toward early PLEX initiation with IVMP+PLEX treatment was observed at 6 months follow-up, however not significantly. Conclusion: Early treatment with PLEX should be encouraged especially in NMOSD with a severe acute attack.

Plasma Exchange for Neuromyelitis Optica Spectrum Disorders in Chinese Patients and Factors Predictive of Short-term Outcome

PurposeThe purposes of this article were to evaluate the short-term outcome of plasma exchange (PLEX) for neuromyelitis optica spectrum disorders (NMOSDs) in Chinese patients and to identify the factors predictive of a favorable response to therapy. MethodsWe retrospectively analyzed data from 29 Chinese patients with NMOSD. All patients received 2 to 7 sessions of PLEX every other day. Expanded Disability Status Scale (EDSS) scores were estimated at baseline, at relapse, and before and at follow-up after PLEX. Patients were assigned to 1 of 2 groups according to treatment responses of marked to moderate improvement and mild to no improvement. FindingsTwenty-four of 29 patients (82.8%) showed functional improvement at 1 month after PLEX, 9 of whom experienced moderate to marked improvement. Early PLEX initiation and a lower baseline EDSS score were independent prognostic factors (both, P < 0.05). In addition, relapse symptoms of nonoptic neuritis and acute transverse myelitis plus circumventricular organs, seronegativity for aquaporin-4 antibodies, shorter initial therapy–PLEX interval, and no prior optic neuritis attacks were predictive factors significantly associated with a favorable response to treatment (all, P < 0.05). The delay time pre-PLEX was inversely correlated with reduction in EDSS score. The percentage reductions in EDSS score in groups receiving PLEX on days ≤15 and days 16 to 30 were significantly greater than those in the groups treated on days 31 to 60 and days 61 to 90 (all, P < 0.05). Most PLEX sessions were generally well tolerated. ImplicationsPLEX is an effective therapy for NMOSD in the Chinese population, and early PLEX initiation was associated with a favorable response. We recommend an optimum PLEX time of 30 days from the time of disease onset. Further long-term prospective, multicenter studies that include a larger sample of patients with NMOSD treated with PLEX are necessary.

Therapeutic Effect of Plasma Exchange in Steroid Refractory Inflammatory Demyelination of Central Nervous System: Outcome from a Tertiary Centre in Malaysia

Objective: To evaluate the efficacy of plasma exchange (PLEX) in steroid refractory inflammatory demyelination diseases (IDD) of Central nervous system (CNS). Methods: Retrospective review of patients presented with steroid refractory IDD from 2006 to 2016 that underwent PLEX. Clinical data on neurological assessment, time to treatment initiation, visual acuity (VA) and Expanded Disability Status Scale (EDSS) were gathered from the medical records. The primary outcome was improvement at 3 months after PLEX. Statistical analysis was done using the SPSS version 21. Results: Forty-three plasma exchanges were performed involving 27 patients (NMOSD= 22, RRMS= 4, ITM= 1). The mean age of patient was 43.60 ± 15.18, and the mean EDSS was 7.98 ± 1.07 at presentation. The anti-AQP4 antibody was detected in 81.5%. Treatment success was observed in 21/43 (48.8%) of patients with a significant improvement of 2.13 EDSS point post PLEX. A lower baseline EDSS score ≤ 6 showed a trend toward good outcome (p= 0.07). AQP4 status had no influence on treatment outcome. Male gender, preserved reflexes, use of DMT and shorter time to PLEX initiation, were not associated with treatment outcome. Conclusion: PLEX is an effective treatment for steroid refractory IDD, regardless of the AQP4 antibody status. A lower baseline EDSS might be associated with a better treatment outcome. PLEX should be considered irrespective of the symptom duration.

Short delay to initiate plasma exchange is the strongest predictor of outcome in severe attacks of NMO spectrum disorders

IntroductionSevere attacks of neuromyelitis optica spectrum disorder (NMO-SD) are improved by plasma exchange (PLEX) given as an adjunctive therapy. Initial studies failed to demonstrate a delay of PLEX treatment influenced...