RT Journal Article SR Electronic T1 Haemophagocytic lymphohistiocytosis associated with Mycobacterium tuberculosis infection JF BMJ Case Reports FD BMJ Publishing Group Ltd SP bcr2014208220 DO 10.1136/bcr-2014-208220 VO 2015 A1 Hui, Yee Man Tracy A1 Pillinger, Toby A1 Luqmani, Asad A1 Cooper, Nichola YR 2015 UL http://casereports.bmj.com/content/2015/bcr-2014-208220.abstract AB Haemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal condition that can be primary or secondary. Secondary HLH can occur in association with infections, most commonly viral infections, but has also been reported in association with Mycobacterium tuberculosis (TB). Prompt identification of the underlying cause of HLH is important as it guides treatment decisions. Early initiation of appropriate treatment (eg, anti-TB treatment) reduces morbidity and mortality. We present a case of HLH associated with TB infection. Initial TB investigations were negative and standard combination chemoimmunotherapy for HLH resulted in a limited clinical response. On apparent relapse of HLH, further investigation revealed TB with changes on CT chest, granuloma on bone marrow and eventual positive TB culture on bronchoalveolar lavage. Subsequent treatment with quadruple anti-TB treatment resulted in rapid clinical response and disease remission. We advocate continued monitoring for TB infection in patients with HLH, and prophylaxis or full treatment for those at high risk.