Acquired hemophagocytic syndrome in a patient with synovial sarcoma: a case report

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome characterized by severe hyperinflammation due to an overwhelming ineffective immune response to different triggers. Most important symptoms are fever, hepatosplenomegaly and cytopenias. Biochemical signs include elevated ferritin, hypertriglyceridemia and low fibrinogen. Hemophagocytosis in the bone marrow is a hallmark of this syndrome. Based on the pathogenetic mechanism, it can be classified into primary (inherited) or secondary (acquired) HLH. We report, to our knowledge, the first case of acquired hemophagocytic syndrome that arose in a 20-year-old man affected by synovial sarcoma as a complication during chemotherapy

Proprotein convertase subtilisin kexin type 9 inhibition for autosomal recessive hypercholesterolemiabrief report

Objective Proprotein convertase subtilisin kexin type 9 (PCSK9) inhibitors lower low-density lipoprotein (LDL) cholesterol in the vast majority of patients with autosomal dominant familial hypercholesterolemia. Will PCSK9 inhibition with monoclonal antibodies, in particular alirocumab, be of therapeutic value for patients with autosomal recessive hypercholesterolemia (ARH)? Approach and Results Primary lymphocytes were obtained from 28 genetically characterized ARH patients and 11 controls. ARH lymphocytes treated with mevastatin were incubated with increasing doses of recombinant PCSK9 with or without saturating concentrations of alirocumab. Cell surface LDL receptor expression measured by flow cytometry and confocal microscopy was higher in ARH than in control lymphocytes. PCSK9 significantly reduced LDL receptor expression in ARH lymphocytes albeit to a lower extent than in control lymphocytes (25% versus 76%, respectively), an effect reversed by alirocumab. Fluorescent LDL cellular uptake, also measured by flow cytometry, was reduced in ARH lymphocytes compared with control lymphocytes. PCSK9 significantly lowered LDL cellular uptake in ARH lymphocytes, on average by 18%, compared with a 46% reduction observed in control lymphocytes, an effect also reversed by alirocumab. Overall, the effects of recombinant PCSK9, and hence of alirocumab, on LDL receptor expression and function were significantly less pronounced in ARH than in control cells. Conclusions PCSK9 inhibition with alirocumab on top of statin treatment has the potential to lower LDL cholesterol in some autosomal recessive hypercholesterolemia patients