History Of Solid Organ Transplantation Research Articles

Successful use of therapeutic plasma exchange for the management of acute lung transplant rejection secondary to immune checkpoint inhibitor therapy

The use of immune checkpoint inhibitors (ICIs) in individuals with a history of solid organ transplantation is fraught with the emergence of solid organ transplantation rejection (SOTR). The current recommendations for the management of SOTRs secondary to ICI include the use of high-dose steroids along with the escalation of immunosuppressive therapy. Therapeutic Plasma Exchange (TPE) has been described to be effective in managing various immune-related toxicities, however, the data for using TPE in the setting of acute SOTRs induced by ICIs are limited. Herein, we describe the successful use of TPE in a patient with a history of bilateral lung transplantation who developed an episode of mixed acute cellular and antibody-mediated lung transplant rejection after a single dose of PD-1 inhibitor Pembrolizumab for the treatment of underlying melanoma.

Predictors of interferon-gamma release assay results and their association with COVID-19 infection outcomes.

An 'indeterminate' interferon-gamma release assay (IGRA) result used in the diagnosis of latent TB infection (LTBI) is most commonly due to an inadequate control (or 'mitogen') response, which may reflect underlying T-cell dysfunction. We performed a single-centre, retrospective study on COVID-19 patients admitted to a tertiary referral hospital who had IGRA testing conducted over a 5-month period. The primary outcomes included predictors of indeterminate IGRA results and associations with COVID-19 outcomes. A total of 181 patients were included for analysis. Approximately one-third of patients hospitalised with COVID-19 with IGRA testing performed (60/181) had an indeterminate result. The likelihood of an indeterminate IGRA was increased in patients with a history of solid organ transplant and a higher severity of COVID-19 at the time of testing. An indeterminate IGRA was associated with a higher risk of severe COVID-19 and a higher risk of admission to the ICU during admission to the hospital. No difference in mortality between the two subgroups was found. Our study demonstrated that COVID-19 patients on immunosuppression had a high likelihood of an indeterminate IGRA result, which was associated with markers of disease severity and immunosuppression. In this cohort, an indeterminate result was associated with worse COVID-19 outcomes.

Electronic health record data shows immunosuppressive conditions are associated with poor outcomes in patients hospitalized for COVID-19

Abstract We identified 10,713 adults hospitalized for COVID-19 from 03/2020 to 05/2022 in electronic health record data from Northwestern Medicine. Based on extracted diagnosis codes, we identified 214 of these adults with primary immunodeficiency (PI), 669 with history of solid organ transplant, and 183 with HIV. Assessed COVID-19 outcomes included mortality, a seven-point ordinal severity scale (1 = Death) based on maximum oxygen requirements during care, and hospitalization length. Patients with PI had a significantly higher mean hospitalization length of 11.8 days and a significantly lower mean maximum severity of 3.3 compared to 7.8 days and 3.9 in immunocompetent patients when controlling for obesity and T2DM. These effects were not significant when controlling for age. Patients with transplant had a significantly higher mean hospitalization length of 15.8 days when controlling for obesity, T2DM, and age, and a significantly lower mean maximum severity of 3.2 when controlling for obesity. Significantly higher mortalities were observed in PI and transplant (RR = 1.5, 95% CI 1.2 to 2.0; RR = 1.5, 95% CI 1.3 to 1.7), but these effects were not significant when controlling for age. There were no significant differences in any outcomes for patients with HIV. Our results suggest patients with PI or transplant hospitalized for COVID-19 may have worse clinical outcomes compared to immunocompetent patients. Meanwhile, patients with HIV had similar outcomes to immunocompetent patients.

Focus on Pneumonia After Organ Transplantation: Is There a Need for Specific Medical Care in the Emergency Department?

Pneumonia is a major cause of hospitalization and has a substantial impact on health care costs. Diagnosis and treatment of pneumonia in solid organ transplant (SOT) patients remain a challenge for clinicians in the emergency department. This study aimed to evaluate demographic features, clinical patterns, history of hospitalization, and diagnosis of adult patients after organ(s) transplantation (liver, kidney, pancreas) with severe pneumonia requiring hospitalization. The aim is to determine whether patients undergoing SOT receive or require specific care and whether they need to be prioritized. This was a single-center observational study of adult patients after SOT with severe pneumonia requiring hospitalization. The data set for the analysis included only patients with pneumonia as the main reason for hospitalization. The diagnosis of pneumonia was suspected based on the American Thoracic Society criteria. The study revealed that the standard of care for patients with a history of SOT did not significantly differ from care provided to the non-SOT patients with pneumonia admitted to the same hospital during a 94-week period. There were notable differences, such as post-transplant patients being transferred more quickly to the hospital ward, having longer hospital stays, and receiving antibiotics earlier than the non-SOT group.

The Influence of Solid Organ Transplant on Inpatient Complications, Length of Stay, and Hospital Costs in Reverse Shoulder Arthroplasty Patients.

With innovations in transplant medicine and longer life expectancies in solid organ transplant (SOT) recipients, the incidence of shoulder arthroplasty is predictably rising in this population. Reverse shoulder arthroplasty (RSA) has become increasingly popular due to advances in prosthetic design with expanded indications. While previous studies have examined shoulder arthroplasty in SOT patients, information specifically related to RSA patients is largely unexplored. We aim to analyze the demographics and characteristics of SOT patients who have undergone RSA while assessing inpatient complication rates, length of stay (LOS), and hospital costs in these patients compared to a matched cohort of non-transplant patients. The National Inpatient Sample (NIS) Database was utilized to identify all patients undergoing RSA from 2016 to 2019. We generated propensity-matched groups based on pre-operative variables (diabetes, tobacco use, sex, age, and obesity) to compare complications, LOS, and inpatient costs between the SOT and control groups. T-tests and Chi-squared tests were performed where appropriate and odds ratios were calculated. We identified 59925 patients who underwent RSA. Among those, 59769 patients (99.7%) did not have a SOT and 156 patients (0.26%) had a history of SOT. Patients in the SOT group were younger than the control group (67.0 versus 71.4 years, p<0.001). The SOT group were more likely males compared to the control group (53.8% versus 39.3%, p<0.001). Following 1:1 matching, there were 156 patients in each group. The SOT group had a higher risk of acute renal failure (ARF) compared to the control group (OR 9.41, 95% CI (2.13-41.49), p<0.001). The LOS (p<0.001) and inpatient costs (p<0.001) were higher in the SOT group. For RSA, SOT patients are younger and more likely male compared to those without SOT. Inpatient medical and surgical complications are similar between SOT and non-SOT patients, except SOT patients have a higher risk of ARF. SOT patients tend to have longer LOS and higher inpatient costs than non-SOT patients.

Fatal form of immune reconstitution inflammatory syndrome (IRIS) developed post pneumonia in a solid organ transplant recipient

BackgroundImmune reconstitution inflammatory syndrome (IRIS) is a complex phenomenon commonly diagnosed with human immunodeficiency virus (HIV). However, rarely, IRIS can develop with other diseases outside of HIV. We are discussing a rare presentation of IRIS following a pseudomonal infection.Case presentationWe present a 79-year-old Hispanic male who completed a course of cefepime for Pseudomonas aeruginosa hospital-acquired pneumonia. The patient had a 21-year history of solid organ transplant and immunosuppressive therapy, and he developed a fatal form of IRIS post-Pseudomonas aeruginosa.ConclusionsIRIS may occur in any immunocompromised patient who develops an insidious onset of unexplained clinical and serological deterioration.

Epidemiological trends and clinical outcomes of cryptococcosis in a medically insured population in the United States: a claims-based analysis from 2017 to 2019.

Emerging risk factors highlight the need for an updated understanding of cryptococcosis in the United States. Describe the epidemiological trends and clinical outcomes of cryptococcosis in three patient groups: people with HIV (PWH), non-HIV-infected and non-transplant (NHNT) patients, and patients with a history of solid organ transplantation. We utilized data from the Merative Medicaid Database to identify individuals aged 18 and above with cryptococcosis based on the International Classification of Diseases, Tenth Revision diagnosis codes from January 2017 to December 2019. Patients were stratified into PWH, NHNT patients, and transplant recipients according to Infectious Diseases Society of America guidelines. Baseline characteristics, types of cryptococcosis, hospitalization details, and in-hospital mortality rates were compared across groups. Among 703 patients, 59.7% were PWH, 35.6% were NHNT, and 4.7% were transplant recipients. PWH were more likely to be younger, male, identify as Black, and have fewer comorbidities than patients in the NHNT and transplant groups. Notably, 24% of NHNT patients lacked comorbidities. Central nervous system, pulmonary, and disseminated cryptococcosis were most common overall (60%, 14%, and 11%, respectively). The incidence of cryptococcosis fluctuated throughout the study period. PWH accounted for over 50% of cases from June 2017 to June 2019, but this proportion decreased to 47% from July to December 2019. Among the 52% of patients requiring hospitalization, 61% were PWH and 35% were NHNT patients. PWH had longer hospital stays. In-hospital mortality at 90 days was significantly higher in NHNT patients (22%) compared to PWH (7%) and transplant recipients (0%). One-year mortality remained lowest among PWH (8%) compared to NHNT patients (22%) and transplant recipients (13%). In this study, most cases of cryptococcosis were PWH. Interestingly, while the incidence remained relatively stable in PWH, it slightly increased in those without HIV by the end of the study period. Mortality was highest in NHNT patients.

Ascitic Fluid Lactate Level as a Predictor of Mortality in Cirrhotic Patients Having Spontaneous Bacterial Peritonitis (SBP).

Introduction Limited studies are available for predicting mortality in patients with spontaneous bacterial peritonitis (SBP) based on ascitic fluid analysis. Recently, a proposition has been made regarding the role of ascitic fluid lactate as a better prognostic indicator of mortality in cirrhotic patients with SBP. Therefore, we aimed to evaluate the utility of ascitic fluid lactate in predicting mortality in cirrhotic patients with SBP. Methods This was a prospective, observational study that was conducted in the Hepato-Gastroenterology Department of Sindh Institute of Urology and Transplantation (SIUT), Karachi from 1January2022 to 31December 2022.All the patients having liver cirrhosis with ascites, aged between 18 and 65 years, and presenting with fever and/or abdominal pain were recruited in the study in the first six months (i.e., from 1January 2022 to 30June 2022) and were followed for sixmore months for the outcome. However, those patients on dialysis or those with hepatocellular carcinoma,any other malignancy as per a history of solid organ transplant, a history of HIV infection, or thoseunderlying systemic sepsis or infections other than SBP were excluded from the study. The presence or absence of SBP was confirmed by doing the ascitic fluid analysis. Ascitic fluid lactate levels were also requested in each patient. Mortality was assessed at one, two, three, and six months, respectively. All the data were analyzed using SPSS version 23.0. The area under the receiver operating curve(AUROC) was obtained for ascitic fluid lactate for predicting mortality in SBP. At an optimal cutoff, the diagnostic accuracy of ascitic fluid lactate was obtained. Results The total number of cirrhotic patients included in the study was 123. The majority of the patients belong to Child Turcotte Pugh (CTP) class C (n = 88; 71%). Two third of the patients (65.8%; n = 81) had viral hepatitis i.e., hepatitis B, D, and/or C, as the cause of cirrhosis. Overall mortality was observed in 51(41.5%) patients. Ascitic fluid lactate was significantly raised in patients with SBP than in patients with non-SBP (p = 0.004). The AUROC of ascitic fluid lactate was highest at three months (AUROC = 0.88) followed by six months (AUROC = 0.84), two months (AUROC = 0.804), and one month (AUROC=0.773). At an optimal cut-off of more than or equal to 22.4 mg/dl, ascitic fluid lactate had a sensitivity of 84.9%, specificity of 85.7%, positive predictive value (PPV) of 97.3%, negative predictive value of 42.8% with diagnostic accuracy of 85% in predicting overall mortality in patients with SBP. On sub-analysis, the diagnostic accuracy of ascitic fluid lactate was highest at six months followed by at three, two, and one month, respectively. Conclusion Ascitic fluid lactate showed a good diagnostic utility in predicting the overall mortality in patients with SBP with the best diagnostic accuracy in predicting long-term (six months) mortality. However, further studies are required to validate our results.

Incidence of formation of anti-D between patients with and without a history of solid organ transplant.

Solid organ transplant surgeries including liver transplants constitute a substantial risk of bleeding complications and given frequent national blood shortages, supporting D-negative transplant recipients with D-negative red blood cell products perioperatively can be difficult for the transfusion services. This study was designed to compare the incidence of alloimmunization after D-mismatched red cell transfusions between patients with and without a history of solid organ transplant at a single tertiary care hospital. The patients undergoing solid organ transplants are on strong immunosuppressive regimens perioperatively to help reduce the risk of rejection. We hypothesized that the use of these immunosuppressive agents makes these patients very less likely to mount an immune response and form anti-D antibodies when exposed to the D-positive red blood cell products perioperatively. At our center, D-negative patients who received ≥1 unit of D-positive red blood cell products were identified using historical transfusion records. Antibody testing results were examined to determine the incidence of the formation of anti-D and any other red cell alloantibodies after transfusion and these results were compared between patients with and without a history of solid organ transplant. We were able to identify a total of 22 patients over 10 years with D-negative phenotype who had undergone a solid organ transplant and had received D-positive red blood cell products during the transplant surgeries. We also identified a second group of 54 patients with D-negative phenotype who had received D-positive red blood cell products for other indications including medical and surgical. A comparison of the data showed no new anti-D formation among patients with a history of D mismatched transfusion during solid organ transplant surgeries. Among our limited study population, we observed a very low likelihood of D alloimmunization among solid organ transplant recipients. A larger, prospective study could help further evaluate the need for prophylactic D matching for red cell transfusions during solid organ transplant surgeries.

Incidence and inhospital outcomes of coronavirus disease 2019-associated pulmonary aspergillosis in the United States.

The aim of this study was to estimate the predictors, associations, and outcomes of COVID-19-associated pulmonary disease (CAPA) in the United States. This retrospective cohort study was performed by using the National Inpatient Sample Database 2020 to identify coronavirus disease 2019 (COVID-19) and CAPA hospitalizations. Baseline variables and outcomes were compared between COVID-19 hospitalizations without aspergillosis and those with aspergillosis. These variables were then used to perform an adjusted analysis for obtaining predictors and factors associated with CAPA and its inhospital mortality. Of the 1,020,880 hospitalizations identified with the principal diagnosis of COVID-19, CAPA was identified in 1510 (0.1%) hospitalizations. The CAPA cohort consisted of a higher proportion of males (58%) as well as racial and ethnic minorities (Hispanics, Blacks, and others [including Asian or Pacific islanders, native Americans]). Inhospital mortality was significantly higher (47.35% vs. 10.87%, P < 0.001), the average length of stay was longer (27.61 vs. 7.29 days, P < 0.001), and the mean cost per hospitalization was higher ($121,560 vs. $18,423, P < 0.001) in the CAPA group compared to COVID-19 without aspergillosis. History of solid organ transplant, chronic obstructive pulmonary disease, and venous thromboembolism were associated with higher odds of CAPA among other factors. The use of invasive mechanical ventilation (adjusted odds ratio [aOR] 6.24, P < 0.001), acute kidney injury (aOR 2.02, P = 0.028), and septic shock (aOR 2.07, P = 0.018) were associated with higher inhospital mortality in the CAPA cohort. While CAPA is an infrequent complication during hospitalizations for COVID-19, it significantly increases all-cause mortality, prolongs hospital stays, and leads to higher hospital expenses compared to COVID-19 cases without aspergillosis.

Diplopia as the presenting symptom of a post‐transplant lymphoproliferative disorder in a bilateral inferior lim transplanted young adult

Aims/Purpose: To present a unique case of post‐transplant lymphoproliferative disorder (PTLD) after bilateral inferior limb transplantation, which is still controversial due to the absence of precedents in the literature and the unclear risk–benefit ratio.Methods: Case report.Results: A 22‐year‐old male presented to the emergency room complaining of double vision. He had a history of bilateral inferior limb amputation 8 years ago and received a bilateral lower limb transplantation 2 years later. He had normal graft function and was receiving cytomegalovirus prophylaxis. During neurological examinations left abducens nerve (CN VI) palsy was noted. Other cranial nerves affected produced facial hypoesthesia (CN V) and mild paresis (CN VII), hearing loss and tinnitus in left side (CN VIII) and soft palate asymmetry (CN X). He was otherwise neurologically intact, alert and orientated. MRI revealed a lesion located at the facial colliculus at the floor of 4th ventricle. In the context of immunosuppression, the differential diagnosis included abscess versus PTLD. Biopsy of the lesion was performed. Morphologically atypical lymphocytic cells suggestive of B lymphoma were identified. Monoclonal rearrangement for heavy chain Igen and immunoglobulins were identified with molecular biology techniques. The histology features were consistent with a diagnosis of CNS B lineage primary lymphoma. Two days later, bilateral supracondylar amputation was performed. Following the explant, immunosuppression was withdrawn. His underlying condition was finally diagnosed as PTLD, for which he started a chemotherapeutic regimen with radical intention (methotrexate and cytosine arabinoside). The patient recovered fully and up to date, 10 years later, is doing well.Conclusions: Due to its diverse aetiologias, a proper workup must be done of the patients presenting with diplopia to the emergency room. PLTD must be a condition to always be considered in patients with history of solid organ transplant; since the early diagnosis is crucial for a successful management of this often‐fatal condition.

977 Severe maternal morbidity and 5-year transplant rejection in pregnant patients with history of solid-organ transplant

977 Severe maternal morbidity and 5-year transplant rejection in pregnant patients with history of solid-organ transplant

Risk Factors for Non-Hodgkin's Lymphoma in Autoimmune Diseases: A Large Database Analysis

Introduction It has been well studied that immune dysregulation in autoimmune diseases is a risk factor for the development of Non-Hodgkin's lymphoma (NHL). However, the underlying mechanisms are not well understood. Although certain traditional risk factors like prolonged immunosuppression, infections, advanced age, family history, and history of organ transplantation are well described in NHL patients, there is limited literature regarding their interplay with autoimmune diseases. Hence, we conducted this retrospective study from the National inpatient sample database to describe the various clinical and demographic factors that increase the risk of NHL development in patients with autoimmune diseases. Methods Our study was conducted using the National Inpatient Sample, which is a large all-payer inpatient care database in the United States. We collected data from 2016-2020 on all adult patients aged &amp;gt; 18 years who had NHL. We divided them into two cohorts: one with underlying autoimmune diseases and one without underlying autoimmune conditions. We then compared the adjusted odds ratios (aOR) of various risk factors like age, race, gender, obesity, family history of lymphoproliferative diseases, personal history of chemotherapy or radiation, history of HIV, HTLV-1, Helicobacter pylori infection, Chlamydia infection, history of solid organ transplantation, and long-term steroid use among the two cohorts. Results Our data initially consisted of 148,755,036 patients ages ≥18 years, with 4,291,559 cases having autoimmune disorders like rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Systemic sclerosis, sarcoidosis, sjogren's syndrome, and celiac disease. We found that 0.9% of autoimmune cases had NHL, while 0.7% of non-autoimmune cases had NHL (aOR 1.272, 95% CI 1.258-1.285, p&amp;lt;0.01). Among those with autoimmune conditions, various factors also influenced the presence of lymphoma, such as personal history of chemotherapy or radiation (aOR 5.778, 95% CI 5.595- 5.9675, p &amp;lt;0.001), family history of lymphoid malignancy (aOR 5.316, 95% CI 4.666-6.058, p&amp;lt;0.001), HIV infection (aOR 1.944, 95% CI 1.674-2.257,p&amp;lt;0.001), advanced age of 60-69 years (aOR 1.051, 95% CI 1.025-1.078, p&amp;lt;0.001) , Asian and Pacific Islander ethnicity (aOR 1.596, 95%CI 1.496-1.703, p&amp;lt;0.001) and viral hepatitis (aOR 1.620, 95% CI 1.480-1.774, p&amp;lt;0.001) (Table 1). Conclusion The increased risk of non-Hodgkin Lymphoma (NHL) with autoimmune conditions like rheumatoid arthritis and SLE is well established. Studies have also shown that these patients can overall have a poor prognosis from their NHL when compared to patients without autoimmune diseases. However, there is limited literature regarding the interplay of traditional NHL risk factors with underlying autoimmunity. Hence, our retrospective analysis sheds light on the lesser studied risk factors, such as patient characteristics and comorbidities. We found that older age, male sex, Asian and Pacific Islander race, family history of lymphoid malignancy, personal history of chemotherapy or radiation, and comorbidities like HIV, Viral Hepatitis, and HTLV-1 are some strong risk factors associated with the development of NHL in patients with autoimmune diseases. Infections like HIV and HTLV-1 played less of a role in the autoimmune cohort as opposed to the non-autoimmune cohort. Whereas personal histories of chemotherapy and radiation and family histories of lymphoid malignancies were demonstrated to be very strong risk factors in both settings. Hence, our study enables clinicians to identify the differences in the interplay of these risk factors and to perform stringent monitoring of patients when they do have these risk factors

1702. Disseminated Candidiasis after Candidemia: Epidemiology, Diagnostic Evaluation, and Risk Factors

Abstract Background In patients with candidemia, evaluation for disseminated disease with ophthalmological exam and diagnostic imaging is recommended but not standardized. This study sought to describe practice patterns in the diagnostic evaluation for disseminated disease after candidemia and identify risk factors associated with disseminated candidiasis to improve local management. Methods A retrospective study of all episodes of candidemia diagnosed in patients &amp;lt; 25 years from 2013-2022 at Cincinnati Children’s Hospital Medical Center reported clinical characteristics, microbiology data, and diagnostic testing for dissemination. Disseminated candidiasis was defined as an ophthalmologic exam, echocardiogram or other imaging findings consistent with candidiasis or growth of Candida spp. from a sterile site besides blood. Mixed-effects logistic regression was performed to identify risk factors for disseminated disease. Results 144 episodes of candidemia occurred in 124 patients , with C. albicans (35%) the most commonly identified species (Figure 1). 107/144 (74.3%) episodes underwent evaluation for disseminated candidiasis, with dissemination in 27/107 (25.2%). Of patients with only 1 positive culture, 5/34 (14.7%) had disseminated candidiasis compared to 22/73 (30.1%) with more than 1 positive culture (Figure 2). Ophthalmologic exams and echocardiograms were done in &amp;lt; 70% of workups (Figure 3). History of prematurity (aOR 17.5, 95%CI 3.1-100.4) and solid organ transplantation (aOR 5.3, 95%CI 1.1-24.6) were associated with disseminated candidiasis when controlling for age, sex, underlying disease, and initial antifungal treatment. Each additional day of candidemia significantly increased the odds of dissemination (aOR 1.5, 95%CI 1.2-1.9). Conclusion In this single-center study, most patients with candidemia underwent diagnostic evaluation, though the extent varied. Disseminated disease was common. Prematurity and history of solid organ transplantation were independent risk factors for dissemination as was each additional day of candidemia. Patients with any candidemia should undergo evaluation for dissemination. Multicenter studies are needed to determine the optimal diagnostic evaluation in these high-risk patient groups. Disclosures Grant C. Paulsen, MD, Moderna: Grant/Research Support|Pfizer: Grant/Research Support Lara A. Danziger-Isakov, MD, MPH, Aicuris: Contracted Clinical Research|Ansun Biopharma: Contracted Clinical Research|Astellas: Contracted Clinical Research|GSK: Advisor/Consultant|Merck: Advisor/Consultant|Merck: Contracted Clinical Research|Pfizer: Contracted Clinical Research|Roche Diagnostics: Advisor/Consultant|Takeda: Advisor/Consultant|Takeda: Contracted Clinical Research William R. Otto, MD, MSCE, Moderna: Grant/Research Support

Outcomes of Head and Neck Microvascular Free Tissue Transfer for Advanced Cutaneous Squamous Cell Carcinoma: A Comparison of Solid Organ Transplant Recipients to Nontransplant Patients

BackgroundPatients with solid organ transplant (SOT) are at increased risk of developing aggressive cutaneous malignancies due to their immunosuppression, particularly cutaneous squamous cell carcinoma PurposeThere is limited data regarding solid organ transplant patients with locally advanced cutaneous squamous cell carcinoma (cSCC) requiring radical surgery and microvascular free tissue transfer (MVFTT). Our objectives were to characterize outcomes in SOT patients and compare them with a non-SOT cohort. Study DesignThis is a retrospective cohort study of patients undergoing MVFTT for advanced cSCC of the head and neck between January 2016 and May 2020 at a tertiary referral center. Patients who underwent MVFTT as part of curative intent surgery for advanced cSCC during the study were considered for inclusion. Exclusion criteria included distant metastasis, palliative intent treatment, age less than 18 years, and lip primaries. PredictorThe predictor variable was SOT status. A cohort of non-SOT patients was matched to the SOT cohort based on age, smoking status, tumor stage, and defect size. Main outcome variablesThe primary reconstructive outcome was the major surgical complications and secondary outcome measures included major medical complications and minor surgical complications. The primary oncologic outcome was overall survival and the secondary outcome was disease-specific survival. The primary predictor was transplant status. CovariatesCovariates included patient comorbidities, prior treatment, tumor stage, type of reconstruction, pathologic findings, and adjuvant therapy. AnalysisContinuous and categorical variables were compared using Student’s T test and Fisher’s exact test. Survival was calculated using the Kaplan-Meier method and differences in survival between groups were calculated using the log-rank test. Statistical significance was set a priori at p ≤ 0.05 ResultsFourteen SOT and 14 matched non-SOT patients met inclusion criteria. There was not a statistically significant difference in the rate of major surgical complications (7% vs 7%, p = 0.74) between the SOT and non-SOT cohorts. Rates of minor (21% vs 43%, p = 0.26) wound complications and medical complications (0% vs 14%, p =0.24) were also similar between the SOT and non-SOT cohorts. Locoregional recurrences and distant metastasis were more common for SOT patients, though this was not statistically significant. Overall survival was significantly worse for SOT patients (21.7 vs 31.0 months, p = 0.04), though there was not a significant difference in disease-free survival (9.8 vs 31.0 months, p = 0.17). Conclusions and RelevanceMVFTT in the management of SOT patients with locally advanced head and neck cSCC demonstrates similar complication rates with non-SOT patients. While survival and oncologic outcomes are worse in the SOT cohort, aggressive surgical intervention with MVFTT can be performed with comparable complication rates to patients without a history of SOT.

The Association Between Solid Organ Transplant and Recurrence of Acute Diverticulitis: A National Assessment.

The aim of this study was to compare rates and severity of recurrent acute diverticulitis in patients with and without solid organ transplant. Immunocompromised solid organ transplant recipients have been considered higher risk for both recurrence and severity of acute diverticulitis. Current guidelines recommend an individualized approach for colectomy in these patients, but these are based on single-center data. We identified patients with acute diverticulitis using the Merative MarketScan commercial claims data from 2014 to 2020. Patients were classified by history of solid organ transplant. The primary outcome was recurrence of acute diverticulitis with an associated antibiotic prescription ≥60 days from the initial episode. Secondary outcomes included hospitalization, colectomy, and ostomy in patients with recurrence. Analyses used inverse probability weighting to adjust for imbalances in covariates. Of 170,697 patients with evidence of acute diverticulitis, 442 (0.2%) had a history of solid organ transplantation. In the weighted cohort, among people who had not been censored at 1 year (n=515), 112 (22%; 95% CI: 20%-25%) experienced a recurrence within the first year. Solid organ transplantation was not significantly associated with a risk of recurrence (hazard ratio=1.19; 95% CI: 0.94-1.50). There was also no statistically significant difference in the hospitalization rate for recurrent diverticulitis. Restricting the analysis to hospitalized recurrences, there was no statistically significant difference observed in either length of stay or discharge status. In this national analysis of commercially insured patients with acute diverticulitis we found no statistically significant differences in recurrence between those with and without a history of solid organ transplant. We do not support an aggressive colectomy strategy based on concern for increased recurrence rate and severity in a solid organ transplant population.

S36 Outcomes of Acute Pancreatitis in Patients With a History of Solid Organ Transplantation

S36 Outcomes of Acute Pancreatitis in Patients With a History of Solid Organ Transplantation

Cancer treatment delays among cancer patients living with HIV during the COVID-19 pandemic in the United States.

The COVID-19 pandemic led to care disruptions across the cancer continuum. It is unknown if immunosuppressed patients with cancer, who may be at higher risk for complications of SARS-CoV-2 infection, are disproportionately impacted. Thus, we aimed to compare delays in cancer treatment initiation between people living with HIV (PLWH) and cancer, the general cancer population (GCP), and patients with cancer and a history of solid organ transplant (SOT). Comparisons were made across the period 2 years preceding the pandemic versus the first year of the pandemic. We used data from a real-world electronic health record-derived de-identified database (2018-2021) comprised of US patients with cancer from 800 sites of care across the country. We included patients with 19 different cancer types. We calculated time to cancer treatment initiation (TTI) as the difference between the date of cancer diagnosis and the earliest date that cancer treatment was recorded. The sample included 181 PLWH, 65,073 GCP patients, and 195 patients with a SOT. Difference-in-difference regression models adjusted for age, sex, and presence of metastatic disease at cancer diagnosis revealed a significant increase in delayed TTI among PLWH compared to the GCP during COVID-19 versus prior to COVID-19, with delays increasing by approximately 1 month during the pandemic (DID: 32.6 days [8.9-56.3]; p = 0.007). The increase in TTI for PLWH was observed across treatment modalities, including surgery (DID: 55.1 [28.8-81.3], p < 0.001) and systemic therapy (DID: 30.4 [4.6-56.3], p = 0.021). PLWH experienced significant delays in cancer treatment initiation after diagnosis during the first year of COVID-19, delays that may negatively impact cancer outcomes. These data warrant patient and provider attention as the pandemic continues to impact the US healthcare system.

Potential drug-drug interactions among U.S. adults treated with nirmatrelvir/ritonavir: A cross-sectional study of the National Covid Cohort Collaborative (N3C).

To estimate the prevalence of potential moderate to severe drug-drug interactions (DDIs) involving nirmatrelvir/ritonavir, identify interacting medications, and evaluate risk factors associated with potential DDIs. Cross-sectional study. Electronic health records from the National COVID Cohort Collaborative Enclave, one of the largest COVID-19 data resources in the United States. Outpatients aged ≥18 years and started nirmatrelvir/ritonavir between December 23, 2021 and March 31, 2022. Nirmatrelvir/ritonavir. The outcome is potential moderate to severe DDIs, defined as starting interacting medications reported by National Institutes of Health 30 days before or 10 days after starting nirmatrelvir/ritonavir. Of 3214 outpatients who started nirmatrelvir/ritonavir, the mean age was 56.8 ± 17.1 years, 39.5% were male, and 65.8% were non-Hispanic white. Overall, 521 (16.2%) were potentially exposed to at least one moderate to severe DDI, most commonly to atorvastatin (19.2% of all DDIs), hydrocodone (14.0%), or oxycodone (14.0%). After adjustment for covariates, potential DDIs were more likely among individuals who were older (odds ratio [OR] 1.16 per 10-year increase, 95% confidence interval [CI] 1.08-1.25), male (OR 1.36, CI 1.09-1.71), smokers (OR 1.38, CI 1.10-1.73), on more co-medications (OR 1.35, CI 1.31-1.39), and with a history of solid organ transplant (OR 3.63, CI 2.05-6.45). One in six of individuals receiving nirmatrelvir/ritonavir were at risk of a potential moderate or severe DDI, underscoring the importance of clinical and pharmacy systems to mitigate such risks.

Outcomes of primary total joint arthroplasty in patients with a history of solid organ transplantation, a single institution analysis

Background: An increasing number of patients with a history of solid organ transplantation (SOT) are presenting for total joint arthroplasty (TJA). The primary aim of this study is to evaluate clinical outcomes after primary total joint arthroplasty in patients with a history of SOT compared to matched controls. Methods: We performed a review of prospectively collected data on consecutive adult patients with a history of SOT undergoing TJA from January 2014 to January 2021. Pearson-Chi square tests were used to compare differences in baseline demographics and clinical characteristics between SOT and matched controls. Multi-variate logistic regression analyses were used to assess whether patients who had a prior SOT were at higher risk of experiencing post-operative complications, readmissions, reoperations, longer length of stay and non-home discharges after primary TJA. Results: A total of 81 operations met inclusion criteria which were compared to 82 age matched controls without a history of SOT. Patients with a history of SOT were more likely to require a hospitalization greater than 2 days compared to the control group (n=63, 77.8% vs. n=16, 19.5%; P=0.011), had an increased risk of hyperkalemia (n=15, 18.5% vs. n=1, 1.2%; P=0.049), and any post-operative complication (n=55, 67.9% vs. n=21, 25.6%; P=0.025). Conclusions: Despite the increased risk of acute post-operative complications and longer hospital stays, primary TJA has been shown to be a safe and effective option for treatment of DJD or AVN in patients with a history of SOT when completed via a multi-disciplinary approach. Level of Evidence: Retrospective Analysis, Level IV.