Rodzinna limfohistiocytoza - seria niefortunnych zdarzeń

Familial haemophagocytic lymphohistiocytosis (FLH) or familial haemophagocytic syndrome is a rare, lifethreatening condition, caused by congenital defect in cellular cytotoxicity, which may be triggered by infections. Cardinal symptoms of this autosomal recessive disease include: prolonged fever, hepatosplenomegaly, duo- or pancytopaenia in peripheral blood. Among laboratory aberrations there are: hypofibrynogenaemia, hypertriglyceridemia, hyperferritinaemia, hypertransaminasaemia, hyperbilirubinaemia and lymphocytic pleocytosis in CSF. Dysfunction of liver and central nervous system, caused by hypercytokinemia and infiltration with hyperactivated cytotoxic T lymphocytes and macrophages, is often present in the course of the disease. Unfortunately, morphological hallmark - haemophagocytosis, observed in hyperactivated macrophages, may not be found in initial bone marrow smears or lymph node examination, which however does not exclude such a diagnosis. If the diagnostic criteria are fulfilled, the initial testing should include determination of perforin expression in NK and CD8+ T cells. This new diagnostic test is currently available in the Children's Memorial Health Institute in Warsaw. Results can be obtained within 2 hours. Patients lacking perforin expression should be analyzed for PRF1 gene mutation, being responsible for approximately 40% of FHL worldwide. Permanent control of the disease is possible only after successful haematopoietic stem cell transplantation (from either related or unrelated donor).