Imported epidemic typhus

Abstract

D Raoult and colleagues (Aug 1, p 353)1Raoult D Ndihokubwayo JB Tissot-Dupont H et al.Outbreak of epidemic typhus associated with trench fever in Burundi.Lancet. 1998; 352: 353-358Summary Full Text Full Text PDF PubMed Scopus (189) Google Scholar report an outbreak of epidemic typhus in Burundi, and cite the first confirmed case in a nurse returning to Switzerland from Burundi. The diagnosis of epidemic typhus in this patient alerted the international health community to the outbreak in Burundi, which ultimately affected more than 43 000 people. We report the clinical course and laboratory investigation that identified this sentinel case. The 38-year-old International Red Cross nurse cared for inmates in the N'Gozi prison in northern Burundi. During the last 2 months of her stay, an unexplained increase in mortality was observed among the prisoners.2Bise G Coninx R Epidemic typhus in a prison in Burundi.Trans R Soc Trop Med Hyg. 1997; 97: 133-134Summary Full Text PDF Scopus (18) Google Scholar 3 days after her return to Switzerland, she developed high fever, chills, and myalgias, and was admitted to hospital 5 days later. Other than fever (39°C), physical examination was unremarkable, with no evidence of a rash. Notable laboratory data included severe thrombocytopenia (50×109/L) and raised D-dimers (4·0 mg/L). Chest radiographs were clear and blood smears were negative for parasites, including Plasmodium spp. Blood and urine cultures were sterile. Initially, the patient's condition was stable, apart from fever, and no antibiotics were administered. 3 days after admission, her platelet count dropped (16×109/L). Because of the patient's travel history and worsening coagulopathy, the clinical differential centred on viral haemorrhagic fevers and typhoid fever; ciprofloxacin (500 mg twice daily) was administered. Her condition deteriorated rapidly, with onset of stupor, dyspnoea, shock and multiorgan failure. She died the following day and a necropsy was done. Histopathological findings include glial nodules in the central nervous system, suggestive of a rickettsial infection. Immunohistochemical staining for typhus group rickettsiae confirmed the diagnosis of typhus (figure). Subsequently, indirect fluorescence antibody testing of acute-phase serum revealed antibody reactive with Rickettsia prowazekii at a titre of 1:2048, and PCR analysis of blood amplified a DNA fragment of the 17 kDa rickettsial surface protein gene with 99·6% homology to R prowazekii. This sentinel case and the subsequent epidemic in Burundi shows us that epidemic typhus is endemic worldwide, with periodic large-scale emergencies. This patient presented with a non-specific febrile illness, highlighting the potential difficulty in the clinical diagnosis of epidemic typhus. This diagnosis should be suspected in any febrile patients with or without a rash who has returned from an area where R prowazekii is endemic, or from a region where there is an epidemic of unknown febrile disease. This report shows how health-care workers are at increased risk for this infection,3Gear J Typhus fever in the Transkei.S Afr Med J. 1944; April 22: 144-148Google Scholar particularly in conditions of overcrowding and poor hygiene, even if the exposure is only transient. Laboratory diagnostics for epidemic typhus seldom affects the management of patients; thus, the potentially rapid clinical progression and associated mortality of untreated epidemic typhus requires prompt administration of appropriate antirickettsial therapy. Although cirofloxacin may be effective, therapy for other select rickettsioses, tetracyclines and chloramphenicol are the drugs of choice in the treatment of epidemic typhus.