Scrub typhus associated macrophage activation syndrome.

Macrophage activation syndrome (MAS) is a rare phenomenon that occurs either primarily or secondary to a multitude of conditions, including juvenile rheumatoid arthritis most commonly, and other infections like enteric fever and tuberculosis. It has been reported as an extremely rare complication of scrub typhus with no cases presented from India. We report three cases of scrub typhus presenting with confirmed MAS between January 2007 and December 2007 to a tertiary care hospital in South India. All three patients had clinical and laboratory evidence for scrub typhus and MAS. All the patients responded promptly to antibiotics and made an uneventful recovery. These three patients are presented to highlight the importance of considering scrub typhus in patients with MAS following acute febrile illnesses.