Evaluation of salivary anti-Salmonella typhi lipopolysaccharide IgA ELISA for serodiagnosis of typhoid fever in children.
This observational study was conducted to determine the diagnostic accuracy of ELISA for the detection of anti-Salmonella typhi lipopolysaccharide (LPS) salivary immunoglobulin A (IgA) antibodies in 37 children with culture confirmed typhoid, 30 febrile controls with an alternative diagnosis and 30 healthy controls. The test was positive in 33/37 (89.2%) cases of typhoid, but negative in all patients in the two control groups. Maximum absorbance of anti-LPS IgA was observed during the second and third weeks of typhoid, with a progressive decline thereafter. The sensitivity of ELISA was 71.4%, 100%, 100%, 9.1% and 0%, in first, second, third, fourth and fifth week of illness, respectively. Further large scale studies measuring salivary anti-LPS IgA antibodies are needed to confirm the potential of saliva-based serology in children with suspected typhoid.
Department of Pediatrics, Jawaharlal Nehru Medical College and Hospital, Aligarh Muslim University, Aligarh-202 002 (UP), India. zzrab@yahoo.co.in
Zeeba
Z
Zaka-ur-Rab
Shaad
S
Abqari
Tabassum
T
Shahab
Najmul
N
Islam
Indu
I
Shukla
D000907:Antibodies, Bacterial / Q000032:analysis*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis*; D007223:Infant; D008070:Lipopolysaccharides / Q000276:immunology; D008297:Male; D012463:Saliva / Q000276:immunology*; D012485:Salmonella typhi / Q000276:immunology*; D012680:Sensitivity and Specificity; D014435:Typhoid Fever / Q000175:diagnosis*
D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D008070:Lipopolysaccharides