Widespread subcutaneous necrosis in spotted fever group Rickettsioses from the coastal belt of Sri Lanka- a case report.

BACKGROUND: Spotted fever group rickettsioses (SFGR) transmitted mostly by ticks are increasingly discovered around the World and some of them are either re-emerging or emerging in Sri Lanka. Accidental human infections caused by these vector borne zoonotic diseases generally give rise to nonspecific acute febrile illnesses which can be complicated by multi organ involvement carrying high morbidity and mortality. Nonspecific clinical features and non-availability of early diagnostic facilities are known to result in delay in the diagnosis of rickettsial infections. Therefore, awareness of their prevalence and more importantly their clinical features would be help in the early diagnosis and institution of appropriate therapy.

CASE PRESENTATION: A 39-year-old otherwise healthy female presented with an acute febrile illness complicated by severe small joint and large joint arthritis, jaundice, acute kidney injury and disseminated intravascular coagulation (DIC) mimicking palindromic rheumatism or severe sepsis. She later developed a widespread fern-leaf pattern necrotic skin rash with evidence of vasculitis on the palms and soles, aiding the clinical diagnosis of SFGR. She had very high antibody titres against R. conorii antigen confirming the diagnosis and recovered completely with anti-rickettsial therapy.

CONCLUSION: We feel that clinicians should be aware of the unusual clinical presentations such as purpura fulminans and 'fern-leaf' pattern necrotic skin rash of SFGR infection. Such knowledge would not only benefit those who practice in tropics with limited diagnostic facilities but also would improve the management of acute febrile illness in returning travelers who visit endemic areas.