Heparin-induced thrombocytopenia with very high antibody titer is associated with slower platelet recovery and higher risk of thrombosis.

Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder mediated by platelet-activating antibodies targeting platelet factor 4 (PF4) and heparin complex. A higher antibody titer is reflected in a higher optical density (OD) by enzyme-linked immunosorbent assay for heparin-PF4 antibodies. This single-institution retrospective study of 116 HIT patients examined the effect of heparin-PF4 OD on time to platelet recovery, vascular thrombosis, and in-hospital mortality. Patients were divided into 3 cohorts based on heparin-PF4 OD: cohort 1 had an OD ≥ 2 and ≤ 2.4, cohort 2 had an OD > 2.4 and ≤ 2.8, and cohort 3 had an OD > 2.8. A higher OD titer was associated with significantly increased time to platelet recovery when compared between cohorts 1 versus 2 (HR = 0.599, p = 0.0221) and 1 versus 3 (HR = 0.515, p = 0.0014), as well as an increased risk of thrombosis (79.4%-cohort 3 vs 53.8%-cohort 2 vs 46.1%-cohort 1, p = 0.04), but had no impact on mortality (2.62-alive vs 2.65-deceased, p = 0.7432). A higher OD titer can inform risk assessment and support decision-making in HIT patients; however, prospective studies are needed to further clarify the impact of heparin-PF4 OD on outcomes.

Interpreting coagulation mixing study results in the era of direct oral anticoagulants.

Interpretation of coagulation mixing studies is complicated by interference arising from direct oral anticoagulants (DOACs), which are increasingly prescribed. In this retrospective study, we reviewed 1035 consecutive coagulation mixing studies performed from 2017 to 2021. Three hundred and ninety-nine cases with normal prothrombin time (PT) and activated partial thromboplastin time (aPTT) were excluded. aPTT mixing studies were performed at time 0 and after 60 min of incubation. We confirmed the presence of interfering factors with additional laboratory testing, medication records, and medical history. Mixing corrected most prolonged PT samples (93%), but 32 cases showed incomplete correction. Of these 32 cases, 18 were confounded by DOAC use, and 3 by factor V (FV) inhibitor. We observed an unusual pattern of prolongation of aPTT after incubation, which was previously considered a characteristic of specific factor inhibitors, most commonly FVIII inhibitor. However, we found that lupus anticoagulant (28%) and DOAC (25%) contributed to this pattern similarly as specific factor inhibitors (28%). Coagulation laboratories should be aware of interference arising from DOACs and other factors in PT/aPTT mixing studies, especially in some unusual correction patterns.

Long-term outcomes in patients with Burkitt lymphoma older than 65 years: an analysis of the Texas Cancer Registry.

Burkitt lymphoma (BL) is an extremely aggressive but curable subtype of non-Hodgkin lymphoma. While younger patients have excellent outcomes in response to aggressive chemoimmunotherapy, the rarity of this disease in older patients and limitations caused by age, comorbidities, and performance status may negate survival advantages. This analysis assessed outcomes of older adults with BL through data provided by the Texas Cancer Registry (TCR). Patients ≥65 years with BL were assessed. Patients were dichotomized into 1997-2007 and 2008-2018. Median overall survival (OS) and disease-specific survival (DSS) were assessed using Kaplan-Meier methodology, and covariates including age, race, sex, stage, primary site, and poverty index were analyzed using Pearson Chi-squared analysis. Odds ratio (OR) with 95% confidence intervals (CI) was used to assess factors contributing to patients not offered systemic therapy. P value <0.05 was considered statistically significant. Non-BL mortality events were also categorized. There were 325 adults, 167 in 1997-2007 and 158 in 2008-2018; 106 (63.5%) and 121 (76.6%) received systemic therapy, a trend that increased with time (p = 0.010). Median OS for 1997-2007 and 2008-2018 was 5 months (95% CI 2.469, 7.531) and 9 months (95% CI 0.000, 19.154) (p = 0.013), and DSS was 72 months (95% CI 56.397, 87.603) (p = 0.604) and not reached, respectively. For patients that received systemic therapy, median OS was 8 months (95% CI 1.278, 14.722) and 26 months (95% CI 5.824, 46.176) (p = 0.072), respectively, and DSS was 79 months (95% CI: 56.416, 101.584) and not reached, respectively (p = 0.607). Age ≥75 years (HR 1.39 [95% CI 1.078, 1.791], p = 0.011) and non-Hispanic whites (HR 1.407 [95% CI 1.024, 1.935], p = 0.035) had poorer outcomes, and patients at the 20-100% poverty index (OR 0.387 [95% CI 0.163, 0.921], p = 0.032) and increasing age at diagnosis (OR 0.947 [95% CI 0.913, 0.983], p = 0.004) were less likely to receive systemic therapy. Of 259 (79.7%) deaths, 62 (23.9%) were non-BL deaths, and 6 (9.6%) of these were from a second cancer. This two-decade analysis of older Texas patients with BL indicates a significant improvement in OS over time. Although patients were more likely to receive systemic therapy over time, treatment disparities existed in patients residing in poverty-stricken regions of Texas and in advancing age. These statewide findings reflect an unmet national need to find a systemic therapeutic strategy that can be tolerated by and augment outcomes in the growing elderly population.

Recurrent Gastrointestinal Bleeding in a Middle-Aged Man.

Acquired von Willebrand disease (avWD) arises because of mechanisms that destroy, decrease, absorb, or clear von Willebrand factor (vWF). A 59-year-old man presented with a 3-year history of recurrent gastrointestinal bleeding. Laboratory workup revealed a prolonged platelet function assay-100. The vWF antigen was decreased, and a low vWF immunofunctional activity/antigen ratio, low collagen binding/antigen ratio, and decreased intermediate and high molecular weight multimers were noted. The patient had no high-shear stress conditions, and an antibody-mediated process was suspected. A vWF mixing study showed complete correction of vWF activity, suggesting no direct functional inhibitor. The patient was given a bolus of vWF concentrate with serial measurements of vWF; the vWF half-life was 2.5 hours. The vWF propeptide/antigen ratio was 4:1, supporting a diagnosis of aVWD resulting from increased antibody-mediated vWF clearance. This case study emphasizes the laboratory's role in the diagnosis and treatment of rare, overlooked acquired bleeding disorders.

Mycobacterial Infections With Ruxolitinib: A Retrospective Pharmacovigilance Review.

BACKGROUND: Ruxolitinib is a selective Janus kinase inhibitor (JAKI) 1/2 approved for the treatment of myelofibrosis (MF) and polycythemia vera (PV). These patients may be at risk for developing opportunistic infections. We assessed the number of patients that developed typical (Mycobacterium tuberculosis [MTB]) and atypical mycobacterial infections (AMI) while on treatment with ruxolitinib by utilizing the United States Food and Drug Administration (FDA) adverse events reporting system (FAERS). MATERIALS AND METHODS: This is a retrospective study utilizing FAERS, a pharmacovigilance database. We queried FAERS for cases of MTB and AMI secondary to ruxolitinib between January 1, 2011 and December 31, 2018. Disproportionality signal analysis was done by calculating the reporting odds ratio (ROR). ROR was considered significant when the lower limit of 95% confidence interval (CI) was > 1. RESULTS: There were 91 reported cases of MTB associated with ruxolitinib compared with 4575 cases from all other drugs. The ROR was significant at 9.2 (95% CI, 7.5-11.4). There were 23 reports of AMI with ruxolitinib compared with 1287 reported with all other drugs. The ROR was significant at 8.3 (95% CI, 5.5-12.6). Twelve (13.2%) patients with MTB and 8 (34.8%) with AMI died. CONCLUSION: Patients on ruxolitinib are at increased risk of developing MTB and AMI. Clinicians should be aware of this risk and consider screening patients for latent MTB prior to initiating ruxolitinib.

Acute myeloid leukaemia presenting as acute liver failure-a case report and literature review.

A 75-year-old woman presented with rapidly progressive fatigue, abdominal pain and jaundice. Physical examination revealed tender abdomen and splenomegaly. Magnetic resonance cholangiogram showed marked hepatomegaly, splenomegaly and scattered nodules or masses in the liver and spleen. The patient expired from multiorgan failure. Autopsy revealed infiltration of the liver, spleen and bone marrow by acute myeloid leukaemia.

The risk of major bleeding in patients with suspected heparin-induced thrombocytopenia.

BACKGROUND: The presence of a hypercoagulable disorder such as heparin-induced thrombocytopenia (HIT) may protect against anticoagulant-associated bleeding. OBJECTIVES: To determine the incidence of major bleeding in patients with suspected HIT. METHODS: We performed a retrospective analysis of 310 patients suspected of having HIT from the Hospital of the University of Pennsylvania and an affiliated community hospital. We compared the cumulative incidence of major bleeding following suspicion for HIT by ultimate HIT status (HIT+ or HIT-) and exposure to an alternative anticoagulant (Tx+ or Tx-). Secondary outcomes included the incidence of new/progressive thrombosis and 30-day mortality. RESULTS: The incidence of major bleeding was high in the HIT+Tx+, HIT- Tx+, and HIT-Tx- groups (35.7%, 44.0%, and 37.3%, respectively). The time to first major bleeding event did not differ between groups (P = .24). Factors associated with increased risk of major bleeding included intensive care unit admission (HR 2.24, 95% CI 1.44-3.47), platelet count < 25 × 109 /L (HR 2.13, 1.10-4.12), and renal dysfunction (HR 1.56, 1.06-2.27); 35.7% of HIT+Tx+, 13.8% HIT-Tx+, and 9.3% of HIT-Tx- patients experienced new or progressive thrombosis. Mortality was similar among the three groups (26.2% HIT+Tx+, 34.5% HIT-Tx+, and 26.7% of HIT-Tx- [P = .34]). CONCLUSIONS: Among patients with suspected HIT, major bleeding was common regardless of HIT status. Contrary to our hypothesis, HIT+ patients were not protected from major bleeding. A better understanding of bleeding risk is needed to inform management decisions in patients with suspected HIT.

Delayed autologous stem cell transplantation following cardiac transplantation experience in patients with cardiac amyloidosis.

This study sought to retrospectively investigate the outcomes of patients with light-chain amyloidosis (AL) with advanced cardiac involvement who were treated with a strategy of heart transplantation (HT) followed by delayed autologous stem cell transplantation (ASCT) at 1-year posttransplant. Patients with AL amyloidosis with substantial cardiac involvement have traditionally had very poor survival (eg, several months). A few select centers have reported their outcomes for HT followed by a strategy of early ASCT (ie, 6 months) for CA. The outcomes of patients undergoing a delayed strategy have not been reported. All patients with AL amyloidosis at a single institution undergoing evaluation for HT from 2004-2018 were included. Retrospective analyses were performed. Sixteen patients underwent HT (including two combined heart-kidney transplant) for AL amyloidosis. ASCT was performed in a total of nine patients to date at a median 13.5 months (12.8-32.9 months) post-HT. Survival was 87.5% at 1 year and 76.6% at 5 years, comparable to institutional outcomes for nonamyloid HT recipients. In addition to these 16 patients, two patients underwent combined heart-lung transplantation. A strategy of delayed ASCT 1-year post-HT for patients with AL amyloidosis is feasible, safe, and associated with comparable outcomes to those undergoing an earlier ASCT strategy.

Autosplenectomy in a Patient with Paroxysmal Nocturnal Hemoglobinuria (PNH).

Autosplenectomy (AS) is a known complication of diseases such as sickle cell anemia, celiac disease, and inflammatory bowel disease. We report the first known case of AS due to paroxysmal nocturnal hemoglobinuria (PNH). A 24-year-old Caucasian male had evidence of hemolytic anemia at the age of 14 and was diagnosed with PNH at the age of 16. He had recurrent episodes of sepsis due to dialysis line infections from poor hygiene, and blood cultures had been positive for multiple organisms including Staphylococcus aureus, Enterococcus faecalis, and Streptococcus pneumoniae. The patient's peripheral blood smears since the age of 14 years demonstrated Howell-Jolly bodies in conjunction with thrombocytopenia and hemolytic anemia, but abdominal ultrasonography reported a normal appearing spleen. The patient presented with septicemia two years after starting eculizumab, and his peripheral blood smear showed extensive Howell-Jolly bodies, Pappenheimer bodies, acanthocytes, and target cells. Splenic ultrasonography demonstrated an atrophic spleen with multifocal scarring, and absent splenic uptake of liver-spleen scintigraphy, consistent with AS. Clinicians should remain vigilant of the potential sequelae of PNH and consider the possibility of the development of AS.

Prospective comparison of the HEP score and 4Ts score for the diagnosis of heparin-induced thrombocytopenia.

The HIT Expert Probability (HEP) score compared favorably with the 4Ts score in a retrospective study. We assessed the diagnostic accuracy of the HEP score compared with the 4Ts score in a prospective cohort of 310 patients with suspected heparin-induced thrombocytopenia (HIT). A member of the clinical team calculated the HEP score and 4Ts score. An independent panel adjudicated HIT status based on a clinical summary as well as the results of HIT laboratory testing. The prevalence of HIT in the study population was 14.7%. At a cutoff of ≥3, the HEP score was 95.3% sensitive (95% confidence interval [CI], 84.2-99.4) and 35.7% specific (95% CI, 29.8-42.0) for HIT. A 4Ts score of ≥4 had a sensitivity of 97.7% (95% CI, 86.2-99.8) and specificity of 32.9% (95% CI, 27.2-39.1). The areas under the receiver operating characteristic (ROC) curves (AUCs) for the HEP score and 4Ts score were similar (0.81 [95% CI, 0.74-0.87] vs 0.76 [95% CI, 0.69-0.83]; P = .12). The HEP score exhibited a significantly higher AUC than the 4Ts score in patients in the intensive care unit (ICU) (0.86 vs 0.79; P = .03). Among trainee scorers, the HEP score performed significantly better than the 4Ts score (AUC, 0.80 vs 0.73; P = .03). Our data suggest that either the 4Ts score or the HEP score may be used in clinical practice. The HEP score may be preferable in ICU patients and among less experienced clinicians.

HITs and misses in 100 years of heparin.

Heparin was discovered 100 years ago, and the heparin-induced thrombocytopenia syndrome was described 40 years ago. That the most powerful anticoagulant of the last century can also produce the most extreme prothrombotic diathesis is but one of the paradoxes that surround heparin-induced thrombocytopenia. Standard treatment is alternative anticoagulation. Advances continue to be made regarding pathophysiology, prevention, and treatment. Currently, an epidemic of overdiagnosis threatens the well-being of patients, so efforts to educate clinicians on when and how to make this diagnosis are pressing.

Recombinant ADAMTS-13: first-in-human pharmacokinetics and safety in congenital thrombotic thrombocytopenic purpura.

Safety, tolerability, and pharmacokinetics of recombinant ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13; BAX 930; SHP655) were investigated in 15 patients diagnosed with severe congenital ADAMTS-13 deficiency (plasma ADAMTS-13 activity <6%) in a prospective phase 1, first-in-human, multicenter dose escalation study. BAX 930 was well tolerated, no serious adverse events occurred, and no anti-ADAMTS-13 antibodies were observed. After single-dose administration of BAX 930 at 5, 20, or 40 U/kg body weight to adolescents and adults, there was approximate dose proportionality with respect to maximum plasma concentration (Cmax [U/mL]) and area under the concentration-time curve (AUC [h∙U/mL]). Dose-related increases of individual ADAMTS-13:Ag and activity were observed and reached a maximum within 1 hour. With escalating BAX 930 doses administered, a dose-dependent persistence of ADAMTS-13-mediated von Willebrand factor (VWF) cleavage products and reduced VWF multimeric size were observed. This study demonstrated that pharmacokinetic parameters of BAX 930 were comparable to those estimated in previous plasma infusion studies and provided evidence of pharmacodynamic activity. This study was registered at www.clinicaltrials.gov as #NCT02216084.

Leukapheresis reduces 4-week mortality in acute myeloid leukemia patients with hyperleukocytosis - a retrospective study from a tertiary center.

Hyperleukocytosis in patients with acute myeloid leukemia (AML) can lead to leukostasis, which if left untreated, has a high mortality. While prompt cytoreductive chemotherapy is essential, treatment with leukapheresis is controversial. This study investigated the outcomes of patients with hyperleukocytosis who received leukapheresis. From 5596 encounters of patients with leukemia seen at Houston Methodist Hospital, we identified 26 patients who had newly diagnosed AML, WBC >50,000/µL, and received leukapheresis. We matched 26 patients who had similar baseline characteristics but did not receive leukapheresis. The primary endpoint was to compare the 28-day mortality rates between the treatment and the control groups. Secondary endpoints were 6-month, 1-year, and 2-year mortality rates. Using multivariate logistic regression analysis, leukapheresis was associated with significantly lower 28-day mortality rate (30.8% vs. 57.7%, p = .022). There was, however, no difference in long-term mortality rate. Our study demonstrates the short-term mortality benefit of using leukapheresis in AML patients presenting with hyperleukocytosis.

Primary thyroid lymphoma presenting as dermatomyositis: a first case and review of the literature.

A 55-year-old woman presented with a 3-week history of weakness. On examination, she had a heliotrope rash, V-neck and shawl signs. There was symmetric proximal muscle weakness, and 2/5 strength in upper and lower extremities. Laboratory values showed CK 5836, CRP 14.9, erythrocyte sedimentation rate 49, lactate dehydrogenase 633, negative antinuclear antibodies and anti-Jo1 antibodies. Muscle biopsy and immunohistochemistry findings were consistent with dermatomyositis. Treatment with high-dose steroids, cyclophosphamide and intravenous immunoglobulin (IVIG) was started, without improvement of symptoms. She was found to have cold agglutinins with a cold screen titre of 1:256,256. Work up for malignancy ensued. Positron emission tomography-computed tomography (PET-CT) showed increased uptake in the thyroid. Fine-needle thyroid biopsy with flow cytometry studies revealed atypical lymphocytes consistent with diffuse large B-cell lymphoma. The patient underwent R-CHOP therapy, with remarkable improvement of her symptoms. Dermatomyositis associated with primary thyroid lymphoma has not been previously reported. This case reinforces the importance of cancer screening in dermatomyositis patients.