Immune-mediated platelet transfusion refractoriness in a severely thrombocytopenic patient with myelodysplastic syndrome successfully treated with romiplostim.

Immune-mediated platelet transfusion refractoriness due to anti-human leukocyte antigen (HLA) antibodies can occur in approximately 9% of patients with myelodysplastic syndromes (MDS) and can lead to an increased risk of clinically relevant bleeds and treatment delays. These patients are typically managed with frequent platelet transfusions; however, HLA-matched platelet transfusions are usually available only in large blood centers. For this reason, alloimunized thrombocytopenic MDS patients are notoriously difficult to manage. Here, we present a case of a MDS patient with an immune-mediated platelet transfusion refractoriness, severe thrombocytopenia and spontaneous subarachnoid hemorhage who we successfully treated with romiplostim, a thrombopoietin receptor agonist.

Circulating YKL-40 in Philadelphia-negative myeloproliferative neoplasms.

Objectives: Philadelphia-negative chronic myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV) and myelofibrosis (MF), are characterized by clonal myeloproliferation and a strong inflammatory atmosphere. YKL-40, expressed in granulocytes, macrophages, megakaryocytes and malignant cells, is an acute phase reactant with an important role in tissue remodeling and atherosclerotic inflammation. The aim of this study was to investigate serum YKL-40 levels in MPNs and to assess its clinical correlations. Methods: ELISA test was used to measure serum YKL-40 levels in 111 MPN patients and in 32 healthy controls. Results: Serum YKL-40 levels were higher in ET, post-ET MF, PV, post-PV MF and primary MF patients, when compared to healthy controls (p < 0.001). Higher serum YKL-40 levels were associated with parameters indicative of the increased inflammatory state (higher C-reactive protein, poor performance status, presence of constitutional symptoms and cardiovascular risk factors). Additionally, higher serum YKL-40 levels in MF patients were associated with blast phase disease, lower hemoglobin and higher Dynamic International Prognostic Scoring System score. In the multivariate Cox regression models, higher serum YKL-40 levels in ET and PV patients were independently associated with an increased risk of thrombosis (HR 4.64, p = 0.031) and impaired survival in MF patients (HR 4.31, p = 0.038). Conclusion: These results indicate that higher circulating YKL-40 levels in MPNs might have a pathophysiological role in disease progression and thrombosis development. Assessing circulating YKL-40 could help in identification of ET and PV patients at a high risk of future cardiovascular events and has a good potential for improving prognostication of MF patients.

Serum procalcitonin in Philadelphia-negative myeloproliferative neoplasms.

Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF), are rare clonal hematopoietic stem cell disorders accompanied by a strong inflammatory milieu, which is directly responsible for constitutional symptoms associated with the disease, such as fever, weight loss or night sweats. Non-hematologists sometimes (and often wrongly) consider the fever in MPN patients to be a symptom of an underlying disease, which may have devastating consequences. Serum procalcitonin (PCT) is a circulating biomarker commonly used to improve the diagnostic accuracy of bacterial infections and to guide antibiotic therapy. The aim of this study was to test whether PCT could aid the clinician in the early diagnosis of bacterial infections in MPNs. This study investigated PCT in 41 ambulatory MPN patients (13 ET, 13 PV and 15 MF) who had no signs of infection and compared it to 10 MPN patients with microbiologically and/or serologically documented bacterial infections. Median PCT in MPN patients was 0.02 ng/mL (range 0.01-0.09 ng/mL). No difference in PCT was found between ET, PV and MF patients (p = 0.993), whereas MPN patients with documented bacterial infections had significantly higher PCT (median PCT 2.45, range 0.90-5.40 ng/mL) when compared to MPN patients with (median PCT 0.03 ng/mL) or without constitutional symptoms (median PCT 0.02 ng/mL; p < 0.001 for both analyses). These results clearly show that PCT should not be considered as a disease biomarker in MPNs and careful clinical assessment for the signs of infection is needed when MPN patients present with fever and high PCT.