Granulomatous fungal and non-tuberculous mycobacterial infestation complicating chronic lung disease: Outcomes in patients undergoing lung transplantation.

INTRODUCTION: Granulomatous infections are common in patients with chronic lung disease. We aim to study the incidence and clinicopathological features of granulomatous infections in a cohort of patients undergoing lung transplantation for end-stage chronic lung disease. METHODS: Pathology reports of 50 explanted native lungs of patients who underwent lung transplantation since 2015 at our institution were reviewed. Four cases with granulomatous lesions were identified. Correlation was made with clinical findings in the 4 cases. RESULTS: The granulomatous infections include non-necrotizing cryptococcal pneumonitis (case 1), necrotizing pneumonia due to Scedosporium sp. and Mycobacterium avium Complex (MAC) (Cases 2 and 3), and invasive Aspergillus pneumonia (Case 4). One patient received pre-transplant fungal prophylaxis (Case 4). Post-transplant infectious complications included invasive (Cases 2 and 4) and non-invasive (Case 1) fungal infections and bacterial pneumonia (Cases 1 and 2). Two patients (Cases 3 and 4) developed acute cellular rejection (ACR) in the first 30 days. The third patient (Case 1) was identified with ACR in the 9 months post-transplant and chronic lung allograft dysfunction at 29 months. In terms of mortality, 1 patient (Case 1) died at 30 months post-transplant from pseudomonal sepsis and chronic graft failure. Two patients with invasive fungal infections (Cases 2 and 4) are on secondary prophylaxis and doing well. One patient (Case 3) remains infection-free and on MAC prophylaxis. CONCLUSIONS: In our case series, patients with chronic lung diseases with superimposed granulomatous infestations frequently experienced post-transplant complications. These include invasive infections and repeat ACRs that predispose patients to chronic graft dysfunction. Pre- and post-transplant antifungal prophylaxis reduces fungal load and complication risk post-transplant.

Acute myeloid leukemia with mutated NPM1 mimics acute promyelocytic leukemia presentation.

OBJECTIVES: To investigate clinicopathological and molecular features of NPM1-mutated acute myeloid leukemia that presented with infrequent acute promyelocytic leukemia (APL)-like phenotype and clinical presentation. METHODS: Cases with both de novo or secondary Acute Myeloid Leukemia (AML) were retrieved. Data from flow cytometry immunophenotyping, cytogenetics, molecular studies, and clinical presentation were analyzed. RESULTS: Cases presented with abnormal coagulation parameters and low platelets count; four of them showed a DIC index compatible with overt DIC. Two cases showed Auer rods. In all cases, immunophenotypes mimicked APL: blasts expressed CD33, CD13, and cytoplasmic MPO but did not express CD34, HLA-DR, or CD11b. Notably, CD4 expression was observed in all cases. Neither t(15;17) nor PML/RARα gene rearrangement was detected. NPM1 gene mutation was identified in all cases. In four cases, TET2 or IDH2 co-mutations were identified. CONCLUSIONS: Our findings provide additional evidence of association between NPM1-mutated AML with TET2 or IDH2 co-mutations and the APL-like immunophenotype. This AML subset was found to exist in both de novo and secondary AML. High WBC count and blasts with low to moderate side scatter and significant expression of CD4 are observed features that could assist in the differential diagnosis with APL. The occurrence of significant elevated D-dimer levels, or even overt DIC observed at diagnosis in these cases could be relevant for this AML subtype.

Clinicopathological manifestations of myocarditis in a heart failure population.

Myocarditis continues to present challenges in diagnosis and management. The goal of this study is to determine the occurrence and manifestations of myocarditis in a heart failure (HF) population. The analyzed patients had acute or persistent HF and were referred over a 6-year period to a quaternary HF center for advanced HF therapies including mechanical circulatory support, left ventricular assist device (LVAD) implantation, and/or heart transplantation. The histopathological diagnosis of myocarditis was made based on the presence of an inflammatory infiltrate of the myocardium, typically with associated cardiomyocyte (CMC) damage, combined as indicated with immunohistochemical and molecular biology characterization. The pathological findings were correlated with a panel of clinical parameters and clinical course of the patients. Myocarditis was identified in 36 patients, with initial diagnoses made in 10 (40%) of 25 by endomyocardial biopsy (EMB), 1 by atrial biopsy (maze procedure), 7 (2.1%) of 331 at LVAD implantation, and 18 (7.8%) of 229 in the explanted heart. There were 20 cases of lymphocytic myocarditis, 4 cases of giant cell myocarditis, 3 cases of eosinophilic myocarditis, and 9 cases of lymphohistocytic with granulomas myocarditis - cardiac sarcoidosis. EMB was performed in 25 patients and was positive in 10 (40%) of cases. Myocarditis was found in 23 explanted hearts including 18 cases de novo and 5 cases with a previously positive specimen. Of the 23 explanted hearts, 21 were nonischemic cardiomyopathy and 2 were ischemic cardiomyopathy. Our findings show that, in patients presenting to a quaternary medical center, myocarditis can be manifest as acute HF as well as a complicating factor in chronic HF.