[Hemophagocytic lymphohistiocytosis in unspecific virus infection]. / Hämophagozytische Lymphohistiozytose bei unspezifischer Virusinfektion.

Hemophagocytic lymphohistiocytosis (HLH), also known as hemophagocytic syndrome or macrophage activation syndrome within a pre-existing rheumatological disease, remains undiagnosed in over 70% of all cases in intensive care units (ICU) due to the sepsis-like clinical presentation. This report describes the case of a 30-year-old previously healthy male patient who was admitted to the normal infectiology ward of the Charité - Universitätsmedizin Berlin with unclear fever after a 3­month journey around Asian and South America. The patient was transferred to the ICU after 3 days because of respiratory failure. Due to the immediate diagnostics of HLH and initiation of specific immunosuppressive treatment with dexamethasone, immunoglobulins and anakinra, the patient completely recovered and could finally be discharged after a 2­week stay in hospital. Furthermore, the current diagnostic and therapeutic options are discussed. Ferritin is a decisive diagnostic marker that should be determined in every patient with unclear organ failure.

Effects of Jak2 type 1 inhibitors NVP-BSK805 and NVP-BVB808 on Jak2 mutation-positive and Bcr-Abl-positive cell lines.

Janus kinases are critical components of signaling pathways that regulate hematopoiesis. Mutations of the non-receptor tyrosine kinase JAK2 are found in many BCR-ABL-negative myeloproliferative neoplasms. Preclinical results support that JAK2 inhibitors could show efficacy in treating chronic myeloproliferative neoplasms. JAK2 has also been postulated to play a role in BCR-ABL signal transduction. Therefore, inhibitors of JAK2 kinases are turning into therapeutic strategies for treatment of chronic myelogenous leukemia (CML). In this study, the effects of two novel JAK2 inhibitors, NVP-BSK805 and NVP-BVB808, have been investigated in cell lines expressing either BCR-ABL or mutant JAK2. Possible synergies between NVP-BSK805/NVP-BVB808 and the kinase inhibitors imatinib and nilotinib were assessed. Proliferation and apoptosis tests with both substances showed response in the following cell lines: CHRF-288-11, SET-2 and UKE-1. All BCR-ABL-positive cell lines showed some reduction in proliferation, but with half-maximal growth-inhibitory values >1 µM. Combination of the JAK2 inhibitors with imatinib and nilotinib showed no significant additive or synergistic effects, although all BCR-ABL-positive cell lines responded well to both CML therapeutic agents. Interestingly, it seemed that the combination of imatinib with NVP-BSK805 had a protective effect on the cells. Combination treatment with nilotinib did not show this effect.

VEXAS and Myelodysplastic Syndrome: An Interdisciplinary Challenge.

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a recently recognized systemic autoinflammatory disease caused by somatic mutations in hematopoietic progenitor cells. This case series of four patients with VEXAS syndrome and comorbid myelodysplastic syndrome (MDS) aims to describe clinical, imaging, and hematologic disease presentations as well as response to therapy. Four patients with VEXAS syndrome and MDS are described. A detailed analysis of imaging features, hemato-oncological presentation including bone marrow microscopy and clinical-rheumatological disease features and treatment outcomes is given. All patients were male; ages ranged between 64 and 81 years; all were diagnosed with MDS. CT imaging was available for three patients, all of whom exhibited pulmonary infiltrates of varying severity, resembling COVID-19 or hypersensitivity pneumonitis without traces of scarring. Bone marrow microscopy showed maturation-disordered erythropoiesis and pathognomonic vacuolation. Somatic mutation in the UBA1 codon 41 were found in all patients by next-generation sequencing. Therapy regimes included glucocorticoids, JAK1/2-inhibitors, nucleoside analogues, as well as IL-1 and IL-6 receptor antagonists. No fatalities occurred (observation period from symptom onset: 18-68 months). Given the potential underreporting of VEXAS syndrome, we highly recommend contemporary screening for UBA1 mutations in patients presenting with ambiguous signs of systemic autoinflammatory symptoms which persist over 18 months despite treatment. The emergence of cytopenia, especially macrocytic hyperchromic anemia, should prompt early testing for UBA1 mutations. Notably conspicuous, pulmonary alterations in CT imaging of patients with therapy-resistant systemic autoinflammatory symptoms should be discussed in interdisciplinary medical teams (Rheumatology, Hematology, Radiology and further specialist departments) to facilitate timely diagnosis during the clinical course of the disease.

Up-regulated MSI2 is associated with more aggressive chronic myeloid leukemia.

A better understanding of events triggering chronic myeloid leukemia progression is critical for optimized clinical management of chronic myeloid leukemia (CML). We sought to validate that increased expression of Musashi 2 (MSI2), a post-transcription regulator, is associated with progression and prognosis. Screening of 152 patients with CML showed that MSI2 was significantly decreased among patients with CML in chronic phase (CP) at diagnosis (p < 0.0001), but found no significant difference between the normal control group and treated patients with CML in CP. Moreover MSI2 was significantly increased (p < 0.0001) in patients with advance disease (AD) CML. Furthermore, our human hematopoietic cell line data imply that MSI2 and BCR-ABL1 mRNA expression are correlated. However, these data cast a doubt on earlier reports that MSI2 effects HES1 expression via NUMB-NOTCH signaling.

Clinical lessons to be learned from patients developing chronic myeloid leukemia while on immunosuppressive therapy after solid organ transplantation: yet another case after orthotopic heart transplantation.

Chronic myeloid leukemia developing after transplantation of solid organs and concomitant immunosuppression is a rare but still significant clinical phenomenon. We here describe an additional case of a 62-year-old male patient developing CML after orthotopic heart transplantation and medication with cyclosporine A, mofetil-mycophenolate, and steroids. Initial antileukemic therapy was imatinib at a standard dose and within 15 months of therapy a complete cytogenetic response was noted. In this report we discuss the clinical implications of these rare but biologically important cases.

JAK2 V617F allele burden quantified by real time quantitative polymerase chain reaction and competitive polymerase chain reaction in patients with chronic myeloproliferative neoplasia.

Assessing the clinical significance of JAK2 V617F mutant allele burden is complicated by a myriad of techniques reported to detect and quantify the mutation. As a consequence, the level of sensitivity and how the data is reported vary. Harmonization of well-defined molecular studies would permit evaluation of the clinical significance of measuring allele burden and rapid determination of the efficacy of novel agents for the treatment of chronic myeloproliferative neoplasia via multicenter clinical trials, at the subclinical level. Here we report a comparison between the widely available TaqMan quantitative real time polymerase chain reaction (Q-PCR) and competitive PCR (C-PCR) assays. We found that the tumor load was invariably greater when measured by C-PCR compared to that recorded by Q-PCR. Furthermore, none of the samples converted from undetectable to detectable when the enriched granulocyte (GR) fraction was tested. While a difference in the V617F allele levels was detected between GR fraction and whole blood, this was not statistically significant.