Hemophagocytic Lymphohistiocytosis Secondary to Salmonella paratyphi a Infection Presenting with Severe Pancytopenia and Multiorgan Dysfunction: The First Case Report

Hemophagocytic lymphohistiocytosis (HLH) or hemophagocytic syndrome is a life threatening hyperinflammatory condition caused by immune dysregulation and resulting in hemophagocytosis and organ damage by activated macrophages and histiocytes. The characteristic clinical features include fever, splenomegaly, cytopenias, liver dysfunction, and hyperferritinemia. HLH can be either primary (genetic), or secondary (acquired HLH) associated with infectious agents, autoimmune diseases, and malignancies. Majority of adult HLH cases are likely to be secondary to an underlying disease. The mortality rates in adults are high, and delayed diagnosis and multiorgan involvement are associated with poor prognosis. A high index of suspicion helps in early diagnosis, and prompt initiation of treatment is absolutely critical. A few cases of secondary HLH associated with Salmonella Typhi infection have been reported in children and young adults. However a thorough literature search by the authors did not show any previous description of secondary HLH associated with Salmonella Paratyphi A infection. In the present article, the authors report the case of an 18 year-old male patient who presented with severe pancytopenia and multiorgan dysfunction and was diagnosed to have secondary HLH, the etiology of HLH being Salmonella Paratyphi A infection. The patient responded to dexamethasone and appropriate antibiotics, with complete reversal of pancytopenia and organ dysfunction. To the knowledge of the authors, this is the first case report of secondary hemophagocytic lymphohistiocytosis caused by Salmonella Paratyphi A.