Changing characteristics of typhoid fever in Taiwan.

Typhoid fever, a systemic disease caused by Salmonella typhi, is classically characterized by fever and abdominal symptoms. Although now considered uncommon, it seems to have re-emerged in Taiwan in recent years. We conducted a retrospective study of the clinical characteristics and microbiologic findings in 24 confirmed cases of typhoid fever treated over a 7-year period at a medical center in northern Taiwan. There were 11 males and 13 females, including 15 adults (over 18 years in age) and 9 children. Their mean age was 24.7 years (range, 9 months to 58 years). Twelve patients had recently returned from abroad, mostly from Southeast Asia. The most common complaints were fever (24/24), diarrhea (18/24), abdominal pain (10/24), and cough (10/24). The average duration of fever before diagnosis was 14.1 days, with a maximum of 30 days. Relative bradycardia was noted in 6 patients. Leukopenia was noted in 2 patients. S. typhi was isolated from blood culture in 20 cases, from stool culture in 3 cases, and from bone marrow culture in 1 case. Widal test was only positive initially in 7/18 cases. Fever of unknown origin was the most common initial diagnosis. Typhoid or enteric fever was impressed initially in only 2 cases. Almost all isolates of S. typhi were susceptible to antibiotics currently used for typhoid fever, with only 1 isolate resistant to chloramphenicol. All patients survived after antibiotic treatment. Only 1 patient developed recurrence after a 10-day course of ceftriaxone. In conclusion, the diagnosis of typhoid fever is often challenging due to non-specific symptoms and lack of an immediate confirmatory test. It is important to include this disease in the differential diagnosis of febrile patients with abdominal symptoms.