Hantavirus Disease and COVID-19

OBJECTIVES

Navajo Nation is disproportionately affected by hantavirus cardiopulmonary syndrome (HCPS), a severe respiratory disease that can quickly progress to respiratory failure and cardiogenic shock. The initial signs and symptoms of HCPS are indistinguishable from coronavirus disease 2019 (COVID-19). However, this distinction is critical, as the disease course differs greatly, with most patients with COVID-19 experiencing mild to moderate illness. We set out to determine if the evaluation of peripheral blood smears for five hematopathologic criteria previously identified as hallmarks of hantavirus infection, or "the hantavirus 5-point screen," could distinguish between COVID-19 and HCPS.

METHODS

The hantavirus 5-point screen was performed on peripheral blood smears from 139 patients positive for COVID-19 seeking treatment from Tséhootsooí Medical Center and two Emory University hospitals.

RESULTS

Of these 139 individuals, 136 (98%) received a score of 3/5 or below, indicating low suspicion for HCPS. While thrombocytopenia, one of the key signs of HCPS, was seen in the patients with COVID-19, it was generally mild and remained stable on repeat specimens collected 12 to 24 hours later.

CONCLUSIONS

Given these findings, the 5-point screen remains a useful rapid screening tool for potential HCPS cases and may be useful to distinguish early HCPS from COVID-19 in HCPS endemic regions.

Measurable (Minimal) Residual Disease in Myelodysplastic Neoplasms (MDS): Current State and Perspectives

Myelodysplastic Neoplasms (MDS) have been traditionally studied through the assessment of blood counts, cytogenetics, and morphology. In recent years, the introduction of molecular assays has improved our ability to diagnose MDS. The role of Measurable (minimal) Residual Disease (MRD) in MDS is evolving, and molecular and flow cytometry techniques have been used in several studies. In this review, we will highlight the evolving concept of MRD in MDS, outline the various techniques utilized, and provide an overview of the studies reporting MRD and the correlation with outcomes.

Molecular Genetic Profile of Myelofibrosis: Implications in the Diagnosis, Prognosis, and Treatment Advancements

Myelofibrosis (MF) is an essential element of primary myelofibrosis, whereas secondary MF may develop in the advanced stages of other myeloid neoplasms, especially polycythemia vera and essential thrombocythemia. Over the last two decades, advances in molecular diagnostic techniques, particularly the integration of next-generation sequencing in clinical laboratories, have revolutionized the diagnosis, classification, and clinical decision making of myelofibrosis. Driver mutations involving JAK2, CALR, and MPL induce hyperactivity in the JAK-STAT signaling pathway, which plays a central role in cell survival and proliferation. Approximately 80% of myelofibrosis cases harbor additional mutations, frequently in the genes responsible for epigenetic regulation and RNA splicing. Detecting these mutations is crucial for diagnosing myeloproliferative neoplasms (MPNs), especially in cases where no mutations are present in the three driver genes (triple-negative MPNs). While fibrosis in the bone marrow results from the disturbance of inflammatory cytokines, it is fundamentally associated with mutation-driven hematopoiesis. The mutation profile and order of acquiring diverse mutations influence the MPN phenotype. Mutation profiling reveals clonal diversity in MF, offering insights into the clonal evolution of neoplastic progression. Prognostic prediction plays a pivotal role in guiding the treatment of myelofibrosis. Mutation profiles and cytogenetic abnormalities have been integrated into advanced prognostic scoring systems and personalized risk stratification for MF. Presently, JAK inhibitors are part of the standard of care for MF, with newer generations developed for enhanced efficacy and reduced adverse effects. However, only a minority of patients have achieved a significant molecular-level response. Clinical trials exploring innovative approaches, such as combining hypomethylation agents that target epigenetic regulators, drugs proven effective in myelodysplastic syndrome, or immune and inflammatory modulators with JAK inhibitors, have demonstrated promising results. These combinations may be more effective in patients with high-risk mutations and complex mutation profiles. Expanding mutation profiling studies with more sensitive and specific molecular methods, as well as sequencing a broader spectrum of genes in clinical patients, may reveal molecular mechanisms in cases currently lacking detectable driver mutations, provide a better understanding of the association between genetic alterations and clinical phenotypes, and offer valuable information to advance personalized treatment protocols to improve long-term survival and eradicate mutant clones with the hope of curing MF.

Primary plasmablastic lymphoma of the gastrointestinal tract: A series of 13 HIV-negative cases and a review of literature

CONTEXT

Primary gastrointestinal plasmablastic lymphoma (GI-PBL) is a rare variant of diffuse B-cell lymphoma with an aggressive clinical course. PBL was initially reported among HIV-positive patients; however, subsequent studies have shown that it also occurs among HIV-negative patients. Its clinical characteristics remain poorly understood. This study aims to retrospectively analyze the clinicopathological findings of primary GI-PBLs in HIV-negative patients.

DESIGN

Primary HIV-negative GI-PBL cases from 2008 to 2022 were reviewed. Clinicopathologic features and outcomes were analyzed.

RESULTS

The cohort of 13 patients had a male-to-female ratio of 9:1 (3 patients' genders not available), with an average age of 61 (range, 30-92) years. The most involved location was the colon (n = 7 [53.8 %]), followed by the small bowel (n = 3 [23.1 %]), stomach (n = 2 [15.4 %]), rectum (n = 1 [7.7 %]), and anus (n = 1 [7.7 %]). Most patients (n = 10 [77 %]) showed isolated GI tract involvement. Eight patients had chronic inflammatory and/or immunocompromised status, including 4 with inflammatory bowel disease (all of whom underwent treatment), 3 with post-organ transplant status, and 1 with irritable bowel syndrome. All cases exhibited cytokeratin-/CD20-/PAX-5-/CD138+ and/or MUM1+ immunophenotype. Based on available data, 8 of 11 (72.7 %) patients had Epstein-Barr virus reactivation. Among 11 patients with follow-up data, the mean follow-up duration was 13.5 (range, 3-40) months; at the end of follow-up, 45.5 % of patients (5 of 11 patients) showed complete remission after chemotherapy.

CONCLUSION

Primary HIV-negative GI-PBL occurs predominantly in the colon of relatively elderly males with immunosuppression. Its clinical course can be heterogenous, presenting a comorbidity with inflammatory bowel disease or post-organ transplantation status.