Hemophagocytic lymphohistiocytosis: A study of 14 cases

Context: Hemophagocytic lymphohistiocytosis (HLH) is a hyperactive, but ineffective immune response releasing proinflammatory cytokines, culminating in multiorgan failure and death. Clinical mimickers, lack of gold standard tests, equivocal diagnostic criteria, and limited literature delay the diagnosis. After a comprehensive literature review, we surmise that this is the largest study in India involving 14 patients. Settings and Design: This was a retrospective observational study. Subjects and Methods: Out of 11,272 bone marrow (BM) examinations in 5 years and 3 months, hemophagocytosis was observed in 133 aspirates. Clinical details of these were reviewed. Results: Fourteen patients fulfilling HLH-2004 criteria were included in the study. Infection associated HLH was seen in 71.4% patients. Malignancy and autoimmune disease were seen in 14.2% patients each. Fever was the most common presentation. Splenomegaly was seen in only 21.4% cases. Cytopaenia was present in all patients. Hypertriglyceridaemia was seen in 85.7% patients. Hyperferritinaemia was seen in 92.8% patients. Hemophagocytosis was seen in all patients. Conclusions: HLH should be suspected in cases with cytopaenia and hyperinflammatory markers. Early BM examination, clubbed with appropriate investigations, points to the diagnosis. Newer diagnostic modalities are available however, not much is known about their efficacy. More research in this field will immensely contribute to timely initiation of therapy and improved outcome of HLH.