Macrophage activation syndrome characterized by all except ?

Ans. is 'd' i.e., Low levels of plasma ferretin Hemophagocytic Lymphohistiocytosis Hemophagocytic lymphohistiocytosis (HLH) is a reactive condition marked by cytopenias and signs and symptoms of systemic inflammation related to macrophage activation. For this reason, it is also sometimes referred to as macrophage activation syndrome. Pathogenesis The common feature of all forms of HLH is systemic activation of macrophages and CD8+ cytotoxic T cells. The activated macrophages phagocytose blood cell progenitors in the marrow and formed elements in the peripheral tissues, while the "stew"of mediators released from macrophages and lymphocytes suppress hematopoiesis and produce symptoms of systemic inflammation. These effects lead to cytopenias and a shock-like picture, sometimes referred to as "cytokine storm" or the systemic inflammatory response syndrome. Familial forms of HLH are associated with several different mutations, all of which impact the ability of cytotoxic T cells and NK to properly form or deploy cytotoxic granules. The most common trigger for HLH is infection, paicularly with Epstein-Barr virus (EBV). Clinical Features Most patients present with an acute febrile illness associated with splenomegaly and hepatomegaly. Hemophagocytosis is usually seen on bone marrow examination, but is neither sufficient nor required to make the diagnosis. Laboratory studies typically reveal anemia, thrombocytopenia, and very high levels of plasma ferritin and soluble IL-2 receptor, both indicative of severe inflammation, as well as elevated liver function tests and triglyceride levels, both related to hepatitis. Coagulation studies may show evidence of disseminated intravascular coagulation. If untreated, this picture can progress rapidly to multiorgan failure, shock, and death. Treatment Involves the use of immunosuppressive drugs and "mild" chemotherapy. Patients with germline mutations that cause HLH or who have persistent/resistant disease are candidates for hematopoietic stem cell transplantation. Without treatment, the prognosis is grim, paicularly in those with familial forms of the disease, who typically survive for less than 2 months.