Initial Blood Tests Research Articles

Abstract Su904: The association between base excess on arrival at the hospital and neurological outcome of adult out-hospital cardiac arrest: observational study

Background: The relationship between base-excess (BE) values, which take into account the time interval from cardiac arrest to blood test, and neurological outcome after out-of-hospital cardiac arrest (OHCA) is not well understood. The purpose of this study was to evaluate the association between BE on arrival at the hospital and neurological outcomes in OHCA patients. Methods: The CRITICAL study, a prospective, multicenter observational study in Osaka, Japan, registered consecutive OHCA patients who were transported to 16 participating critical care centers from 2012 to 2021. We included adult patients aged 18 years with witnessed OHCA whose BE values on hospital arrival was available, and divided patients into quartiles based on BE values of initial blood test on arrival at the hospital: Q1 (BE ≤ −21.1 mmol/L), Q2 (−21.1 < BE ≤ −15.7 mmol/L), Q3 (−15.7 < BE ≤ −10.4 mmol/L), and Q4 (BE > −10.4 mmol/L). The primary outcome was one-month survival with favorable neurological outcome, defined as cerebral performance category scale 1 or 2. Results: A total of 23,854 patients were registered, and 6,066 of them were eligible for analyses. Neurologically favorable outcome was the lowest in the Q1 group (3.2% [49/1,528]), followed by the Q2 (4.7% [70/1,493]), Q3 (9.8% [148/1,515]), and Q4 (23.5% [359/1,530]) group. In the multivariable logistic regression analysis, the adjusted odds ratio of Q1 compared with Q4 for one-month favorable neurological outcome was 0.13 (95% CI 0.090–0.18). The proportion of one-month favorable neurological outcome decreased progressively across decreasing quartiles (p for trend < 0.001). In subgroup analysis, there was an interaction between presence of return of spontaneous circulation (ROSC) before blood test and neurological outcome (p for interaction < 0.001). The neurological outcome worsened as the BE values decreased among those who achieved ROSC before the blood test (p for trend < 0.001), but not in those without ROSC (p for trend = 0.078). There was not a significant interaction between BE values without ROSC before blood test and time from witness to blood test (p for interaction = 0.501). Conclusions: We demonstrated that lower BE values at hospital arrival were associated with worse neurological outcome. The BE values may be one of the effective prognostic indications for neurological outcome, especially in OHCA patients with ROSC before hospital arrival.

Hemophagocytic lymphohistiocytosis caused by multiple infections during primary chemotherapy for pediatric acute lymphoblastic leukemia: a case report

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory disorder that occurs as a consequence of immune dysregulation. HLH can be primary (familial or non-familial) or secondary to infection, autoimmune disease or malignancy. Malignancy-associated HLH is often accompanied by hematologic and lymphoid neoplasms. This report describes the case of a 3-year-old girl with an initial diagnosis of acute lymphoblastic leukemia who subsequently developed HLH during primary chemotherapy. She was admitted with a pulmonary infection, and initial blood tests showed thrombocytopenia and anemia. Whole-exome sequencing of gene and whole transcriptome RNA sequencing data indicated mutations of UNC13D. The hospital course was complicated by multiple infections, altered mental status and acute respiratory distress syndrome. HLH secondary to multiple infections that achieved remission following targeted therapy with ruxolitinib, in conjunction with corticosteroids and other complementary treatments. This report provides a synopsis of the diagnostic and treatment procedures implemented in this case.

Acute pancreatitis following asparaginase treatment in pediatric acute lymphoblastic leukemia with a heterozygous SPINK1 c.194 + 2T>C intronic variant: a case report

BackgroundAsparaginase is a critical component of chemotherapy for pediatric acute lymphoblastic leukemia (ALL), but its use is often complicated by asparaginase-associated pancreatitis (AAP). Genetic predispositions, such as variants in the SPINK1 gene, have been linked to an increased risk of pancreatitis. However, the role of genetic factors in relation to asparaginase treatment remains incompletely understood, partly because mutations in pancreatitis-causing genes are rarely found in pediatric ALL.Case descriptionA four-year and three-month-old Chinese girl was admitted to our hospital due to fever for half a day, with no history of significant prior medical history. Initial blood tests revealed hematological abnormalities, including leukopenia, anemia, and thrombocytosis. Bone marrow aspiration identified 81.5% blast cells with B-lymphocyte morphology and immunophenotype, leading to a diagnosis of B-cell acute lymphoblastic leukemia (B-ALL). The patient began treatment under the CCCG-ALL-2015 protocol, which included PEG-asparaginase (PEG-asp). On day 10 of induction, she developed AAP, which was primarily characterized by severe epigastric pain and elevated serum amylase. Despite effective symptom management with analgesics and anti-inflammatory therapy, AAP recurred following administration of L-asparaginase (L-asp). Genetic analysis revealed a heterozygous SPINK1 c.194 + 2T>C variant (rs148954387), a well-known pathogenic variant associated with increased susceptibility to pancreatitis. Sanger sequencing confirmed that the SPINK1 variant was inherited from her asymptomatic mother. The patient's AAP was managed conservatively, and an asparaginase-free regimen ultimately achieved complete remission without recurrence of pancreatitis.ConclusionsThe identification of the SPINK1 c.194 + 2T>C variant, which is recognized as pathogenic, provides valuable information for understanding the heightened risk of AAP in our pediatric ALL patient. Our case underscores the potential role of genetic predisposition in the development of AAP and highlights the importance of considering genetic screening prior to asparaginase therapy in pediatric ALL patients to identify those at increased risk.

35 Discriminating bacteremia from contaminants among children with a preliminary positive blood culture in the emergency department

Abstract Background Children with preliminary positive blood cultures in the emergency department (ED) often prompt urgent actions due to the risk of bacteremia. Distinguishing true bacteremia from contaminated cultures is crucial to safely prevent unnecessary, potentially harmful interventions. Objectives This study aimed to assess a peer institution algorithm for discriminating bacteremia from contaminants in discharged ED patients, and to identify variables associated with bacteremia in children with positive blood cultures. Design/Methods This was a retrospective study of all children with positive blood cultures from a tertiary care, paediatric ED between 2018 and 2022. The primary outcome was true bacteremia as defined using a two-step standardized approach based on the bacteria involved and the clinical outcome assessed by two reviewers for each case. The independent variables assessed were demographic data (age and sex), presence of underlying disease, initial blood tests (CBC, CRP), Gram stain, time for positivity (in hours), presence of alternative diagnosis, fever at phone follow-up. The association between independent variables and outcome was measured using logistic regression. It was estimated that a sample of 500 participants would yield at least 200 true bacteremias and allow the evaluation of 20 risk factors. Results 574 participants; 286 (49.8%) with bacteremia and 288 (50.2%) with contaminants were included. Utilizing the algorithm, 364 children (63%) were classified as high risk of true bacteremia, 178 (31%) as medium risk, and 32 (6%) as low risk. Corresponding bacteremia probabilities were 62%, 34%, and 0%, yielding 100% sensitivity (95% CI: 94-100%) and 11% specificity (95% CI:7.7-15%). A sub-analysis restricted to the 165 patients who were initially discharged classified 104 (63.0%) children at high risk, 35 (32.1%) at medium risk and 26 (15.7%) at low risk with proportions of bacteremia of 53.8%, 11.4% and 0 % respectively. The most significant predictors of bacteremia included suspicion of osteoarticular infection (OR: 40.4), presence of internal hardware (OR: 24.6), presence of Gram negative bacteria or Gram positive cocci in chains/pairs (OR: 25.4), and positivity within 19 hours (OR: 3.72). Conclusion While half of the positive blood cultures in our paediatric ED are contaminants, multiple risk factors of true bacteremia were identified. A peer institution algorithm is 100% sensitive to detect discharged patients with bacteremia, it demonstrated low specificity in our population. Multiple improvements opportunities are identified.

Prediction of intensive care unit admission using machine learning in patients with odontogenic infection.

This study aimed to develop and validate a model to predict the need for intensive care unit (ICU) admission in patients with dental infections using an automated machine learning (ML) program called H2O-AutoML. Two models were created using only the information available at the initial examination. Model 1 was parameterized with only clinical symptoms and blood tests, excluding contrast-enhanced multi-detector computed tomography (MDCT) images available at the initial visit, whereas model 2 was created with the addition of the MDCT information to the model 1 parameters. Although model 2 was expected to be superior to model 1, we wanted to independently determine this conclusion. A total of 210 patients who visited the Department of Oral and Maxillofacial Surgery at the Dankook University Dental Hospital from March 2013 to August 2023 was included in this study. The patients' demographic characteristics (sex, age, and place of residence), systemic factors (hypertension, diabetes mellitus [DM], kidney disease, liver disease, heart disease, anticoagulation therapy, and osteoporosis), local factors (smoking status, site of infection, postoperative wound infection, dysphagia, odynophagia, and trismus), and factors known from initial blood tests were obtained from their medical charts and retrospectively reviewed. The generalized linear model algorithm provided the best diagnostic accuracy, with an area under the receiver operating characteristic values of 0.8289 in model 1 and 0.8415 in model 2. In both models, the C-reactive protein level was the most important variable, followed by DM. This study provides unprecedented data on the use of ML for successful prediction of ICU admission based on initial examination results. These findings will considerably contribute to the development of the field of dentistry, especially oral and maxillofacial surgery.

Preoperative Autologous Blood Donation for Rh-Negative Pregnant Women Undergoing Cesarean Sections.

Cesarean sections (C-section) often require blood transfusions in cases of severe bleeding, particularly challenging in Rh-negative pregnancies due to the scarcity of Rh-negative donors, with only approximately 0.3% of the population in Thailand. Autologous blood donation, where individuals donate their own blood before surgery, offers a promising solution. Our study focused on preparing preoperative autologous blood donations (PAD) for Rh-negative pregnancies. We conducted blood screening on 7,182 pregnancies at Takuapa Hospital from October 2013 to September 2018, identifying 21 Rh-negative pregnant women. We established criteria based on hemoglobin (Hb) levels, which are crucial for autologous blood preparation (Hb at 11.0 g/dL, and hematocrit (Hct) above 33%). Blood samples were collected twice during pregnancy, at 36 and 37 weeks, with the second collection 1 week before the C-section. Pregnancies testing positive for infectious markers were excluded following standard blood donation guidelines. Twelve pregnant women testing negative for infectious markers were enrolled. The demographic data showed 12 subjects aged 17 to 41 years, with an average of 27.83. Initial blood tests indicated Hb and Hct levels of 12.5 g/dL, and 36.4%, slightly decreasing to 12.2 g/dL and 35.8% in the second collection. On the day of the cesarean, levels further declined to 11.6 g/dL and 34.4%, respectively, within normal ranges. At discharge, the Hct measured 34.8%. Maternal and infant health post-C-section were good, with baby weights ranging from 2,640 to 4,080 g. None of the 12 cases required autologous blood transfusion, validating the safety of standard autologous blood preparation practices. This study highlights the safety of autologous blood donation for pregnant women with rare blood types, which was achieved through effective planning and collaboration among hospital departments. These findings can serve as a model for other hospitals and significantly reduce the burden of searching for Rh-negative donors.

Painful Enlarging Cervical Mass in Young Male.

A 32-year-old male who recently immigrated from Kenya presented to the emergency department (ED) with a painful, enlarging, right-sided neck mass for eight weeks duration. Point-of-care ultrasound was used to reveal a large cystic mass with internal septations and numerous hypoechoic round lesions. Initial tuberculosis blood test ordered in the ED was positive with cultures ultimately growing Mycobaceterium tuberculosis. Scrofula should be considered in the differential in patients presenting with enlarging neck masses who have epidemiological risk factors for tuberculosis.

Not all ketosis is type 1 – remember Flatbush

A 35-year-old otherwise healthy gentleman from Togo, was referred as a ‘walk-in’ to our clinic with polyuria and polydipsia, and a glycated haemoglobin (Hba1c) of 119 mmol/mol (13.1%). The patient also noted 5kg weight loss over a short span of time. He had a significant family history of Type 2 Diabetes Mellitus (T2DM). Initial blood tests revealed a blood glucose of 22.84 mmol/L, with positive ketones (1.2 mmol/L). Urinalysis showed glycosuria (1000 mg/dL) but was negative for nitrites and white cells. Renal, liver and thyroid function tests were all within normal limits. He had mild metabolic acidosis.

The impact of using SGLT-2 inhibitor on left ventricular longitudinal strain and NT-proBNP levels during six-month follow-up in diabetic patients with and without coronary artery disease with preserved ejection fraction.

Optimal glycemic control is necessary to prevent cardiovascular events in patients with type 2 diabetes. The positive impact of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on cardiovascular events and mortality in these patients has been demonstrated by previous studies although the mechanism is unclear. We aimed to compare the influence of SGLT2i on left ventricular remodeling and strain in diabetic patients with coronary artery disease (CAD) and without CAD during 6-month follow-up. Between October 2021 and June 2022, 100 diabetic patients with preserved ejection fraction (HbA1c levels 6.5-10%) were started on SGLT2i (empagliflozin or dapagliflozin) and were prospectively followed up. Conventional and speckle-tracking echocardiography was performed by blinded sonographers, at baseline and then at 1 month and 6 months of treatment. After 6 months, the initial and biochemical blood tests were administered, and N-terminal pro-B-type natriuretic peptide levels of the patients were measured. Patients with CAD were older (P = 0.008), more frequently hypertensive (P = 0.035), and had dyslipidemia (P = 0.021). N-terminal pro-B-type natriuretic peptide levels did not change significantly after treatment in both groups. Left ventricular ejection fraction, global, 2-chamber, and 3-chamber strain values were improved significantly following SGLTi administration for the overall patient cohort, regardless of CAD status (P < 0.05 for all groups). Treatment with SGLT2i resulted in improvement in left ventricular strain parameters, which indicates that they might have a positive impact on outcomes for diabetic patients with preserved EF.

A Rare Case of Tuberculous Constrictive Pericarditis Due to Disseminated Tuberculosis with Response to Anti-tuberculosis Chemotherapy and Steroids in a Developed City State

A 27-year-old man presented with a 1-week history of atypical chest pain and sinus tachycardia. His physical examination was unremarkable. His resting ECG showed sinus tachycardia with widespread T-wave inversion. His initial blood tests show mildly raised troponin T and inflammatory markers and marked raised D-dimer. A CT pulmonary angiogram was performed to exclude pulmonary embolism but incidentally revealed an anterior mediastinal mass. A transthoracic echocardiogram and cardiac MRI showed features of constrictive pericarditis. A video-assisted thoracoscopic surgical biopsy of the anterior mediastinal mass showed thymic tissue with necrotising granulomatous inflammation and an acid-fast bacilli culture was positive to tuberculosis infection. The patient was started on anti-tuberculosis chemotherapy and a 6-week tapering course of oral steroids. A repeat cardiac MRI performed after 6 weeks of treatment showed a significant response to treatment with resolution of constrictive physiology.

Attitudes to multi-cancer early detection (MCED) blood tests for population-based screening: A qualitative study in Great Britain

BackgroundTrials are underway to test the clinical utility of multi-cancer early detection (MCED) blood tests for screening asymptomatic individuals. We sought to understand the acceptability of MCED blood test screening and potential barriers and facilitators to participation among the general public. MethodsWe conducted eleven semi-structured online focus groups with 50-77-year-olds (n = 53) in April–November 2022. Participants were purposefully sampled to include a mix of socio-economic and ethnic backgrounds as well as people who would not want ‘a blood test for cancer’. Participants were shown information about MCED blood tests. Transcripts were analysed using reflexive thematic analysis. ResultsParticipants showed enthusiasm for MCED screening. Perceived benefits included procedural familiarity and the potential to screen for many cancers. Enthusiasm was driven by beliefs that cancer is a real and increasing risk (both at population level and personally with age) and that early detection reduces treatment burden and cancer mortality. Some felt they would not want to know if they had cancer. The potential for MCED tests to raise anxiety was a concern, especially in a false-positive scenario. Participants wanted to avoid unpleasant and unnecessary procedures. The initial blood test was deemed “less invasive” than current screening tests, but potential follow-up procedures were a concern. Views on MCED screening were influenced by wider factors including dislike of uncertainty, desire for choice and control over one's health, and existing relationships with the NHS. ConclusionThe introduction of MCED screening is likely to be appealing due to the simplicity and familiarity of the primary test procedure. Test accuracy needs to be high to facilitate acceptability and should be communicated from the outset. Some people would rather not know if they have cancer, and MCEDs will not appeal to all.

Monitoring trends in the absolute lymphocyte count and the neutrophil-to-lymphocyte ratio in patients with breast cancer receiving eribulin

BackgroundStudies have shown that the absolute lymphocyte count (ALC) and the neutrophil-to-lymphocyte ratio (NLR) are related to the outcomes in patients with breast cancer receiving specific chemotherapies. However, the reports have focussed on the initial blood test and there is a lack of evidence or data to support that dynamic changes of ALC or NLR are associated with the patients’ survival outcomes.MethodsWe retrospectively reviewed electronic medical records from patients with breast cancer treated with eribulin from 2015 to 2019 at our institution. Blood test data were available prior to starting eribulin (baseline), and at 1, 3 and 6 months after initiating eribulin. We classified the patients into ALC and NLR high and low groups using the following cut-offs: 1000/µl for ALC and 3 for NLR. We defined ALC and NLR trends as increasing or decreasing compared with the initial data. We assessed the associations between the ALC and NLR with progression-free survival and overall survival.ResultsThere were 136 patients with breast cancer treated with eribulin. Of these patients, 60 had complete blood tests and follow-up data. Neither a high ALC nor a low baseline NLR was associated with the survival outcome. One month after initiating eribulin treatment, a high ALC and a low NLR were significantly associated with longer progression-free survival (p = 0.044 for each). Three months after initiating eribulin, a high ALC was significantly associated with better overall survival (p = 0.006). A high NLR at 3 or 6 months after initiating eribulin was associated with worse overall survival (p = 0.017 and p = 0.001, respectively). The ALC and NLR trends across times were not associated with survivals.ConclusionWe showed that 1, 3 and 6 months after initiating eribulin, a high ALC and a low NLR may be related to the patients’ survival outcomes. The ALC and NLR trends were not associated with survival. Accordingly, we believe patients who maintain a high ALC and a low NLR may have better clinical outcomes after initiating eribulin.

Monitoring the Efficacy of High-Flow Nasal Cannula Oxygen Therapy in Patients with Acute Hypoxemic Respiratory Failure in the General Respiratory Ward: A Prospective Observational Study.

High-flow nasal cannula (HFNC) is widely used to treat hypoxemic respiratory failure. The effectiveness of HFNC treatment and the methods for monitoring its efficacy in the general ward remain unclear. This prospective observational study enrolled 42 patients who had acute hypoxemic respiratory failure requiring HFNC oxygen therapy in the general adult respiratory ward. The primary outcome was the all-cause in-hospital mortality. Secondary outcomes included the association between initial blood test results and HFNC outcomes. Regional ventilation distributions were monitored in 24 patients using electrical impedance tomography (EIT) after HFNC initiation. Patients with successful HFNC treatment had better in-hospital survival (94%) compared to those with failed HFNC treatment (0%, p < 0.001). Neutrophil-to-lymphocyte ratios of ≥9 were more common in patients with failed HFNC (70%) compared to those with successful HFNC (52%, p = 0.070), and these patients had shorter hospital survival rates after HFNC treatment (p = 0.046, Tarone-Ware test). Patients with successful HFNC treatment had a more central ventilation distribution compared to those with failed HFNC treatment (p < 0.05). Similarly, patients who survived HFNC treatment had a more central distribution compared to those who did not survive (p < 0.001). We concluded that HFNC in the general respiratory ward may be a potential rescue therapy for patients with respiratory failure. EIT can potentially monitor patients receiving HFNC therapy.

Prognostic value of initial routine laboratory blood tests in patients with aneurysmal subarachnoid hemorrhage requiring mechanical ventilation: a retrospective cohort study.

Aneurysmal subarachnoid hemorrhage (aSAH) necessitating mechanical ventilation (MV) presents a serious challenge for intensivists. Laboratory blood tests reflect individual physiological and biochemical states, and provide a useful tool for identifying patients with critical condition and stratifying risk levels of death. This study aimed to determine the prognostic role of initial routine laboratory blood tests in these patients. This retrospective cohort study included 190 aSAH patients requiring MV in the neurosurgical intensive care unit from December 2019 to March 2022. Follow-up evaluation was performed in May 2022 via routine outpatient appointment or telephone interview. The primary outcomes were death occurring within 7 days after discharge (short-term mortality) or reported at time of follow-up (long-term mortality). Clinico-demographic and radiological characteristics, initial routine laboratory blood tests (e.g., metabolic panels and arterial blood gas analysis), and treatment were analyzed and compared in relation to mortality. Multivariable logistic and Cox regression analyses, with adjustment of other clinical predictors, were performed to determine independent laboratory test predictors for short- and long-term mortality, respectively. The patients had a median age of 62 years, with a median World Federation of Neurosurgical Societies grade (WFNS) score of 5 and a median modified Fisher grade (mFisher) score of 4. The short- and long-term mortality of this cohort were 60.5% and 65.3%, respectively. Compared with survivors, non-survivors had more severe disease upon admission based on neurological status and imaging features and a shorter disease course, and were more likely to receive conservative treatment. Initial ionized calcium was found to be independently associate with both short-term [adjusted odds ratio (OR): 0.92; 95% confidence interval (CI): 0.86 to 0.99; P=0.020] and long-term mortality [adjusted hazard ratio (HR): 0.95; 95% CI: 0.92 to 0.99; P=0.010], after adjusting for potential confounders. Moreover, the admission glucose level was found to be associated only with short-term mortality (adjusted OR: 1.19; 95% CI: 1.06 to 1.34; P=0.004). Laboratory screening may provide a useful tool for the management of aSAH patients requiring MV in stratifying risk levels for mortality and for better clinical decision-making. Further study is needed to validate the effects of calcium supplementation and glucose-lowering therapy on the outcomes in this disease.

CPC03 Triad of generalized rash, peripheral eosinophilia and coexisting obstructive airway disease

Abstract An 87-year-old woman was referred to the acute dermatology service with a 1-week history of a generalized painful rash. She was under the care of the medical team for treatment of pneumonia with symptoms of a cough, fevers and shortness of breath. Her past medical history included adult-onset asthma, hyponatraemia and hypertension. She had never smoked. On examination, she had erythematous smooth papules and plaques on her limbs and torso with palmoplantar involvement, alongside purple macules and patches where older lesions were present. There was no lymphadenopathy and no mucosal involvement. She had an oxygen requirement of 2 L per minute via nasal cannula. Initial blood tests showed eosinophils of 2.8 × 109 cells L−1 and a C-reactive protein (CRP) of 77 mg L−1. A chest radiograph showed bilateral ill-defined shadowing. Two skin punch biopsies were performed for histology and immunofluorescence. Vasculitis screen identified positive antinuclear antibodies (anti-Ro) and reduced complement C4 with negative antineutrophil cytoplasmic antibody (ANCA). The patient remained unwell with increasing CRP and peripheral eosinophilia (up to 9.2 × 109 cells L−1) with rash progressing to exhibit a reticular pattern. Alongside bilateral patchy ground glass opacification on chest computed tomography, a clinical diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA) was made. Differential diagnoses included viral exanthem, erythema multiforme and urticarial vasculitis. Screening for cardiac, renal and sinus involvement was undertaken. The patient improved clinically following the initiation of systemic steroids and the peripheral eosinophilia returned to baseline. Skin histology reinforced the clinical diagnosis of EGPA, demonstrating a dermal and perivascular eosinophilic infiltrate with focal extension into vessel walls. EGPA is a rare small- to medium-sized vessel vasculitis with an annual incidence of 0.9–2.4 per million and a median age at diagnosis of 49–59 years. The clinicopathological hallmarks, as in this case, are asthma with peripheral eosinophilia and pulmonary eosinophilic infiltrates. Median time from onset of asthma to presentation with EGPA is 5–9 years. EGPA remains a clinical diagnosis, reinforced by serological and histological findings, although ANCA is reported to be negative in 60–70% of cases. Systemic steroids are the first-line therapy, with a role for second-line immunosuppressants such as methotrexate and rituximab. The key learning points from this case are to keep an open mind in considering a systemic cause for cutaneous manifestations, especially when the patient does not fulfil the usual demographic picture.

Classification Model for Epileptic Seizure Using Simple Postictal Laboratory Indices.

Distinguishing syncope from epileptic seizures in patients with sudden loss of consciousness is important. Various blood tests have been used to indicate epileptic seizures in patients with impaired consciousness. This retrospective study aimed to predict the diagnosis of epilepsy in patients with transient loss of consciousness using the initial blood test results. A seizure classification model was constructed using logistic regression, and predictors were selected from a cohort of 260 patients using domain knowledge and statistical methods. The study defined the diagnosis of seizures and syncope based on the consistency of the diagnosis made by an emergency medicine specialist at the first visit to the emergency room and the diagnosis made by an epileptologist or cardiologist at the first outpatient visit using the International Classification of Diseases 10th revision (ICD-10) code. Univariate analysis showed higher levels of white blood cells, red blood cells, hemoglobin, hematocrit, delta neutrophil index, creatinine kinase, and ammonia levels in the seizure group. The ammonia level had the highest correlation with the diagnosis of epileptic seizures in the prediction model. Therefore, it is recommended to be included in the first examination at the emergency room.

Prospective evaluation of cell-free DNA fragmentation profiles for lung cancer detection.

e20521 Background: Annual lung cancer screening can save lives, but fewer than 10% of eligible persons participate each year. More widespread screening is hindered by cost, inaccessibility, and uncertainty over individual-level benefit vs risk. Screening rates could be raised by a simple, inexpensive initial blood test, if it were sensitive for cancer detection. The DELFI (DNA evaluation of fragments for early interception) technology uses low-coverage, whole-genome sequencing and machine learning to identify patterns of cell-free DNA (cfDNA) fragmentation associated with cancer. Here we report preliminary cfDNA analysis results from DELFI-L101 (NCT04825834), a prospective, observational, multistate case-control study to train and test DELFI classifiers for lung cancer detection. Methods: Enrollees were ≥50 years old with current or previous smoking histories of ≥20 pack-years and recent or planned chest CT imaging. Medical history was recorded at enrollment, and blood samples were collected for DELFI analysis. Repeated 10-fold cross-validation was used to develop a classifier for lung cancer detection. A split study approach is planned for independent validation of the classifier. Results: At this time, 242 individuals with lung cancer and 652 without cancer have enrolled. Most participants were ≥65 years old, and the proportions of men and women were similar. Lung cancer risk factors were present among both cases and controls. Like the lung cancer screening population, approximately half of lung cancer cases were stage I. Median DELFI scores were higher among individuals with lung cancer than no cancer, overall and across groups stratified by age or body mass index (BMI). Cross-validated area under the receiver operator characteristic curve was 0.81 for lung cancer detection. Clinically meaningful sensitivity to detect lung cancer was attained across all disease stages, with sensitivity increasing stepwise with stage. Conclusions: We developed a classifier based on cfDNA fragmentome patterns analyzed using DELFI that could differentiate between lung cancer cases and controls with cross-validated performance across age groups, BMI categories, and cancer stages. A blood-based DELFI fragmentome test could serve as a low-cost, high-performance blood test with potential to improve lung cancer screening efficiency. Clinical trial information: NCT04825834 .

A Rare Case of Hyperfunctioning Lipoadenoma Presenting as a Cystic Pararthyroid Lesion.

A 58-year-old woman visited the hospital complaining of fatigue and indigestion lasting for more than 3 months. She had no medical history other than taking a calcium plus vitamin D supplement for osteopenia. The initial blood test showed a high calcium level of 14.0 mg/dL. Additional tests were performed to differentially diagnose hypercalcemia. The blood test results were as follows: serum parathyroid hormone (PTH)=247.0 pg/mL, PTH-related peptide <1.0 pg/mL, phosphorous=2.6 mg/dL, 25-hydroxy-vitamin D=14.5 pg/mL, creatinine=1.09 mg/dL, and 24 hr urine calcium=215 mg/dL. A 4.5 cm sized cystic lesion on the intra-thyroidal space was confirmed on neck sonography and 4-dimensional parathyroid computed tomography, but technetium-99m methoxyisobutylisonitrile parathyroid scintigraphy showed equivocal results. After removal of the cystic lesion, serum calcium and PTH were normalized, and parathyroid lipoadenoma was confirmed in the postoperative pathology. Clinical features of parathyroid lipoadenoma are known to be similar to common parathyroid adenoma, but imaging studies often report negative findings. Therefore, it is necessary to better understand this rare disease for the differential diagnosis. For the final diagnosis and treatment of this disease, parathyroidectomy with intraoperative PTH measurement may be required.

P025 The knee that gave it away: a case report of melioidosis

Abstract Background/Aims Melioidosis, an infectious disease caused by the Burkholderia pseudomallei is very rare within the UK. This gram-negative bacterium is endemic in Southeast Asia predominately Thailand and Northern Australia which is found within the soil and fresh surface water. We present a challenging case of melioidosis who was diagnosed following a culture of a discharging knee swelling. Methods N/A Results 35-year-old, Caucasian gentleman with no previous past medical history presented with a ten week history of diffuse abdominal pain, weight loss, dry cough, fatigue and night sweats. On examination, he appeared pale and initial bloods showed a CRP of 229 mg/L. His other initial observations and baseline blood tests were normal. Abdominal ultrasound detected free peritoneal fluid and a subsequent CT chest and abdominal showed abnormal thickening of his small bowel, mediastinal and retroperitoneal lymphadenopathy along with bilateral pulmonary nodules. A laparoscopy and laparotomy with peritoneal, intraperitoneal and mesenteric lymph node biopsies were inconclusive. Microscopy and culture (MC&amp;S) as well as acid fast bacilli MC&amp;S were both negative. He continued to have systemic symptoms, as well as elevated inflammatory markers. He underwent a bronchoscopy which showed erythematous and a nodular endobronchial mucosa with white plaques seen within the lower trachea and minor narrowing of the lumen. Endobronchial biopsies showed chronic inflammation with no evidence of any malignant cells. Repeated bloods including retroviral screening, anti-nuclear antibody (ANA) and antinuclear cytoplastic antibodies (ANCA) and serum ACE were normal. At this stage, the clinical picture was suggestive of sarcoidosis, however a subsequent rigid bronchoscopy and biopsy did not evidence of granulomas or vasculitis. The patient started to develop increasing right knee swelling with difficulty in walking. The swelling burst open, and the discharging fluid was sent for MC&amp;S. This was positive for Burkholderia pseudomallei. The gentleman completed a 20-week course of antibiotics with clinical resolution. Conclusion Meliodosis can cause a wide range of clinical manifestations varying from asymptomatic to septicemia, osteomyelitis, abscesses, septic arthritis and encephalomyelitis. Our case had travelled to Thailand around 8 months prior to the onset of symptoms. This highlights the possible long latent period between exposure and clinical presentation. Definite diagnosis is through isolation of Burkholderia pseudomallei in cultures. This proved challenging in our case, as multiple biopsies and cultures from different sites did not grow the bacterium. The diagnosis was confirmed following knee fluid culture. Musculoskeletal involvement of melioidosis is a known presentation and its potential to mimic other conditions, may render a diagnostic challenge especially when it occurs outside an endemic area. The case highlights the need for rheumatologists to have a high level of clinical suspicion for early detection, isolation of the organism and proper disease management. Disclosure A. Maksoud: None. L. Sammut: Other; LS has received funding for educational events and activities - from Lilly, Roche/Chugai.

Mycobacterium genavense splenitis in a pet rabbit (Oryctolagus cuniculus) presented for fracture

Mycobacteriosis is an uncommon infection that has been sporadically described among wild, farmed and pet rabbits. To date, only one case of Mycobacterium genavense infection has been reported in a dwarf rabbit presenting with granulomatous pneumonia. This new case report describes granulomatous splenitis caused by M. genavense in a pet rabbit brought in for lameness caused by a femoral fracture. The initial blood test, X-ray, abdominal ultrasound, and bone marrow and spleen cytology results were consistent with a diagnosis of a metastatic giant-cell tumour. The rabbit underwent successful femoral osteosynthesis, and six months later, following the occurrence of a second spontaneous fracture and a worsening of overall health, the patient was euthanised. The postmortem histological examination showed severe granulomatous splenitis caused by acid-fast bacilli identified as M. genavense by real-time PCR analysis. The route of infection remains unknown, yet the lack of pulmonary involvement likely rules out airborne transmission. M. genavense infection, although rarely described in pet rabbits, appears to be an emerging pathogen and should be included among the differential diagnoses for pneumonia and splenomegaly.