Acquired bleeding disorders secondary to immune checkpoint inhibitors: a case report and systematic literature review.

Acquired bleeding disorders because of an autoimmune phenomenon are rare events. Acquired von Willebrand disease (aVWD) has been estimated as having a prevalence of 400 per million in the general population. Acquired hemophilia A (AHA), the most common of the acquired hemophilias, has an estimated incidence of 1.3-1.5 cases per million per year. Immune checkpoint inhibitors (ICI) targeting PD-1, PD-L1, and CTLA-4 are being used with increasing frequency for hematologic and oncologic disorders. Acquired hemophilias and aVWD have been reported with the use of ICI therapy. We performed a systematic review of the literature to identify cases of acquired bleeding disorders with ICI therapy and contribute our own institution's experience with a case of AHA after pembrolizumab therapy. Six cases of AHA, one case of aVWD, and one case of factor V inhibitor were identified in the literature. Inhibitors were successfully eradicated in five of the eight cases identified. We propose that a centralized registry, possibly through the Scientific and Standardization Subcommittee on Plasma Coagulation Inhibitors through the International Society on Thrombosis and Hemostasis (ISTH), be developed to record treatment and outcomes of this rare ICI complication in order to prognosticate risk and better understand optimal treatment strategies.

An untapped resource: characteristics of thrombus recovered from intermediate or high risk pulmonary embolus patients.

INTRODUCTION: Response to anticoagulation varies during management of acute hospitalized pulmonary embolism. We aimed to study thrombus histology in pulmonary embolism samples removed during acute surgical embolectomy to evaluate whether thrombus morphology was similar between patients and whether there was an association with duration of symptoms and/or resolution on follow up imaging. METHODS: This was a retrospective observational single center study at the University of Rochester Medical Center. We evaluated patients that underwent acute surgical embolectomy and followed up in our clinic 2 - 4 months after the event with Ventilation/Perfusion (V/Q) scan obtained for all regardless of symptoms. Thromboemboli were formalin fixed and processed for light microscopy in the hospital histopathology laboratory. Four-micron thick sections were stained with hematoxylin and eosin, Masson trichrome, and Verhoeff elastic tissue stains. Immunohistochemistry was performed using anti-CD31 and anti-CD68. Slides were independently evaluated for time-dependent microscopic changes using Irniger's classification by two blinded pathologists. RESULTS: Sixteen patients underwent embolectomy with fifteen having V/Q imaging at follow up. The majority of patients were female. Samples showed a generally similar overall architecture that included a central core composed primarily of red blood cells and fibrin and an outer layer of platelets and monocytes. Two samples had evidence of fibrosis and recanalization. CONCLUSIONS: We found heterogeneous histopathology in samples obtained during acute embolectomy. Further prospective studies should systematically characterize clot morphology and evaluate treatment response and outcomes. Careful thrombus specimen measurement and consistent sampling for sections will be required to draw firm conclusions.

Resting heart rate as a surrogate for improvement in intermediate risk pulmonary embolus patients?

BACKGROUND: Pulmonary embolism (PE) response teams (PERT) have been developed to improve in-hospital mortality. Identifying intermediate risk PE patients that will progress despite anticoagulation is difficult, especially because outcomes with modern anticoagulation are quite good. OBJECTIVE: The primary aim of this study was to evaluate the rate of anticoagulation failure (new deep vein thrombosis or PE, right ventricular failure resulting in shock, cardiac arrest, or PE-attributable death) in intermediate risk PE patients managed by PERT. The secondary objective was to determine whether there was a significant decrease in heart rate 24 h after initiation of anticoagulation in intermediate risk PE. METHODS: This was a retrospective observational study of patients treated for acute intermediate risk PE at the University of Rochester Medical Center who also had outpatient followup between November 2016-June 2019. RESULTS: Ninety-two patients presented as intermediate-risk PE and had outpatient followup. Seventy-four patients were initially treated with anticoagulation. None of these patients failed anticoagulation. Of the eighteen intermediate risk patients that underwent advanced intervention, none failed anticoagulation first. There was significant decrease in resting heart rate 24 h after starting therapeutic anticoagulation, 107 beats/min vs 89 beats/min, p = 0.0001. CONCLUSION: We did not observe anticoagulation failure in the management of acute, intermediate risk PE. Reductions in heart rate may reflect improvements in right ventricular function; we hypothesize that those whose heart rate does not fall may be optimal candidates for advanced intervention.

Direct oral anticoagulant therapy in patients with morbid obesity after intermediate- or high-risk pulmonary emboli.

There is little reported on the efficacy and safety of direct oral anticoagulants (DOACs) in morbid obesity after venous thromboembolism (VTE). In this observational study, patients were followed up after intermediate- or high-risk pulmonary embolism (PE) at the University of Rochester Pulmonary Hypertension Clinic 2-4 months after the initial event. All patients had echocardiography and V/Q imaging regardless of symptoms. Outcomes of interest were the rates of recurrent VTE, thrombus resolution and development of chronic thromboembolic pulmonary hypertension (CTEPH) in patients with morbid obesity treated with a DOAC compared to treatment with vitamin K antagonists and to non-morbidly obese patients after PE. Using the electronic medical record, recurrent events were assessed up to 12 months after the event. 107 patients (body mass index (BMI)>40 kg·m-2, n=32; BMI 30-39.9 kg·m-2, n=39; BMI<30 kg·m-2, n=36) attended follow-up appointments after treatment for PE. A DOAC was used in 70 patients (BMI>40 kg·m-2, n=19; BMI 30-39.9 kg·m-2, n=27; BMI<30 kg·m-2, n=24). There were no recurrent events within the first 12 months of initial diagnosis based on symptoms and imaging in any patient. There was no difference in rate of residual unmatched perfusion defect with DOACs or conventional anticoagulation (49% versus 49%). This finding remained in the subset of morbidly obese patients (47% versus 50%). For the overall cohort, there was no difference in the rate of CTEPH development based on anticoagulation with a DOAC (5% versus 8% with warfarin). There were no major bleeding complications with a DOAC. DOAC therapy appears to be effective and safe in morbid obesity even after intermediate- or high-risk PE. ​.

A Morphometric Analysis of Platelet Dense Granules of Patients with Unexplained Bleeding: A New Entity of Delta-Microgranular Storage Pool Deficiency.

One thousand and eighty patients, having prolonged bleeding times, frequent epistaxis, menorrhagia or easy bruising or other bleeding manifestations, and excluding those with von Willebrand's disease, were evaluated for platelet dense granule deficiency. The mean diameter of platelet dense granules was determined for all patients using image analysis. Four hundred and ninety-nine had "classic" dense (delta) granule storage pool deficiency (δ-SPD). Five hundred and eighty-one individuals (53.8%) were found to have a normal mean number of dense granules, but for some of these patients, the dense granules were smaller than for the controls. Of the patients having a normal number of dense granules, 165 (28.4%) were found to have significantly smaller granules than the platelets obtained from the control subjects. Their average granule diameter was 123.35 ± 0.86 nm, that is more than three standard deviations below the mean of the control data. Total δ-granule storage pool volumes (TDGV)/platelet were calculated using these measurements. Individuals with δ-SPD had half the number of granules (2.25 ± 0.04 DG/PL) and storage pool volume (3.88 ± 1.06 × 106 nm3) when compared to our control data (4.64 ± 0.11 DG/PL; 10.79 × 106 nm3 ± 0.42). Individuals having a bleeding history but a normal average of small dense granules had a calculated storage pool volume statistically different than controls and essentially the same storage pool volume as patients with δ-SPD. We have identified a sub-classification of δ-SPD that we have defined as micro-granular storage pool deficiency (δ-MGSPD).

Chronic therapeutic anticoagulation is associated with decreased thrombotic complications in SARS-CoV-2 infection.

BACKGROUND: Thrombotic disease complicates severe SARS-CoV-2 infection and is associated with increased morbidity and mortality. Various anticoagulation strategies have been evaluated in hospitalized patients to prevent complications. The impact of chronic anticoagulation before SARS-CoV-2 infection on the risk for subsequent thrombosis has not been systematically studied. METHODS: This was a retrospective single-center study. All patients with positive SARS-CoV-2 PCR testing from March 13, 2020, through May 6, 2020, at the University of Rochester Medical Center were identified. We included all patients receiving therapeutic anticoagulation for at least 1 month before COVID diagnosis. We documented the rate of thrombotic complications, type of anticoagulation, bleeding complications, and mortality. RESULTS: A total of 107 SARS-CoV2-infected patients were chronically anticoagulated before SARS-CoV-2 testing with a median age of 78. Of those, 42 required hospital admission, with 17 requiring intensive care. No patients, inpatient or outpatient, were diagnosed with a new symptomatic thrombotic complication. Three patients had minor bleeding in the hospital. Thirteen (12%) patients died (69% male). CONCLUSION: Our uncontrolled findings suggest that chronic anticoagulation at the time of infection may protect against thrombotic complications and decrease disease severity.

Duplication of chromosome 1 [dup(1)(q21q32)] as the sole cytogenetic abnormality in a patient previously treated for AML.

A nonrandom structural gain of 1q may be seen in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), and often it is due to an unbalanced translocation. Dup(1)(q21q32) as the sole abnormality has only rarely been reported. Reports have suggested that the dup(1)(q21q32) is predictive of a poor prognosis. We describe a case report of a 55 year old male who presented in 2002 with AML-M2, t(8;21)(q22;q22). He underwent induction with "7+3" followed by consolidation chemotherapy resulting in a complete remission. Two years later, his bone marrow revealed a dup(1)(q21q32) as an isolated aberration for the first time. In 2010, cytogenetic analysis of the bone marrow again confirmed this finding and FISH for AML1/ETO t(8;21) remained negative. Dup(1q) developed as an isolated abnormality two years after AML treatment, and to date, there is no evidence of progression to MDS. This is the first report of an acquired dup(1)(q21q32) as the sole abnormality in a patient treated for AML. This suggests that the dup(1q) may not be exclusively associated with a poor prognosis.