Evidence of acute rickettsioses among patients presumed to have chikungunya fever during the chikungunya outbreak in Sri Lanka.

BACKGROUND: Chikungunya fever (CGF) and rickettsioses are known to cause acute onset febrile illnesses associated with severe arthritis. Rickettsial arthritis is curable with the use of appropriate anti-rickettsial antibiotics, however the arthritis of CGF tends to have a prolonged course leading to protracted disability. The aim of this study was to investigate the contribution of CGF and rickettsioses to cases of fever and arthritis during a presumed CGF outbreak in Sri Lanka. METHODS: Fifty-eight consecutive patients with presumed CGF were further investigated to determine the occurrence of rickettsioses among them, and to identify differences in clinical, hematological, and biochemical parameters between the two diseases. RESULTS: Nearly a third of the patients had serological evidence of rickettsioses accounting for their illness. The presence of a late onset major joint arthropathy sparing the small joints of the hands and feet, and the occurrence of a late onset discrete maculopapular rash over the trunk and extremities, suggested rickettsioses over CGF. White blood cell count, erythrocyte sedimentation rate, C-reactive protein, and liver function tests were not helpful in differentiating rickettsioses from CGF. Patients with rickettsioses and arthritis who received an empirical course of doxycycline recovered faster than those who did not receive specific treatment. CONCLUSIONS: The establishment of rapid diagnostic methods able to differentiate the etiological agents of fever and arthritis, such as CGF and rickettsioses, would be beneficial in endemic settings.

Contribution of rickettsioses in Sri Lankan patients with fever who responded to empirical doxycycline treatment.

Twenty-eight febrile Sri Lankan patients with undiagnosed fever for 7 days after hospital admission, who responded to empirical treatment with doxycycline, were retrospectively investigated using microimmunofluorescence assay to verify whether they had rickettsial infection. Eleven (39%) patients were confirmed as having spotted fever group rickettsioses and 10 (36%) as having Orientia tsutsugamushi. Seven were negative for all tests. This suggests that greater use of doxycycline appears justified for patients with undiagnosed fever in settings where rickettsial diseases are endemic or re-emerging with inadequate diagnostic facilities.

Scrub typhus mimicking enteric fever; a report of three patients.

We report three patients who presented with fever and late onset diarrhoea mimicking enteric fever. All three patients were diagnosed with an Orientia tsutsugamushi infection and responded dramatically to doxycycline treatment. Clinicians practicing in rickettsial disease endemic areas should be made aware of similar clinical presentations in order to prevent morbidity and mortality associated with rickettsioses.

Rickettsioses presenting as major joint arthritis and erythema nodosum: description of four patients.

Erythema nodosum and aseptic arthritis are recognized associations of rickettsial infections. However, they usually present with a febrile illness rather than with severe arthritis. We report three patients who presented with incapacitating major joint arthritis and one who presented with severe spondyloarthropathy in addition to major joint arthritis due to serologically confirmed Orientia tsutsugamushi and Rickettsia conorii infections. All of them had erythema nodosum and low-grade fever. They had rapid clinical response to doxycycline.