Diagnosis of typhoid fever by detection of Salmonella typhi antigen in urine.
A monoclonal antibody specific for group D Salmonella antigen 9 was used in an indirect enzyme-linked immunosorbent assay (ELISA) for detecting the antigen in urine specimens collected from patients with clinical typhoid fever in Jakarta, Indonesia. The ELISA had a sensitivity of 95% in identifying patients in whom Salmonella typhi was isolated from hemocultures, 73% in patients in whom S. typhi was isolated from stool specimens, and 40% in patients in whom the organism was isolated from bone marrow cultures. Among patients in whom S. typhi was isolated from blood cultures, the ELISA had a sensitivity of 65% when a single urine specimen was examined and 95% when serially collected urine specimens were examined. A dot blot immunoassay performed on a nitrocellulose filter in parallel had a sensitivity of 85%, versus 83% for the plate ELISA in which S. typhi was isolated from blood, bone marrow, and/or stool specimens. Since S. typhi antigen is intermittently excreted in the urine of patients with typhoid fever, serially collected urine from patients with typhoid should be tested for antigen 9.
Chaicumpa
W
W
Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
Ruangkunaporn
Y
Y
Burr
D
D
Chongsa-Nguan
M
M
Echeverria
P
P
D000942:Antigens, Bacterial / Q000652:urine*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D012485:Salmonella typhi / Q000276:immunology*; D012680:Sensitivity and Specificity; D014435:Typhoid Fever / Q000175:diagnosis*
D000942:Antigens, Bacterial