A descriptive analysis of clinico-demographic features and microbiological results of typhoid fever suspected patients in four large hospitals of Bhutan

Introduction: Bhutan reports about 2000 typhoid fever cases annually. We aimed at understanding the clinico-demographic features and microbiological results of patients with suspected typhoid fever. Methods: A yearlong (2012) study of typhoid fever suspects was conducted to describe and analyse associations of demographic and clinical features with laboratory findings. Results: A total of 457 patients were enrolled. Most patients were from Phuntsholing General Hospital (n=181; 39.6%) followed by Jigme Dorji Wangchuck National Referral Hospital (n=170; 37.2%), Eastern Regional Referral Hospital (n=56; 12.3%) and Central Regional Referral Hospital (n=50; 10.9%). Fever (n=420; 91.9 %) and headache (n=397; 86.9 %) were the commonest symptoms reported by the patients. Only 30% (n=137) and 11.2% (n=51) had diarrhoea and constipation respectively. Mean duration of illness was 11.2 days. Among the 457 Widal tests performed, 76.1% (n=348) were negative, 12.3 % (n=56) positive for O antigen, 8.5% (n=39) for H antigen and 3.1% (n=14) for both. Only 2 of the 109 (1.8%) patients with a positive Widal test had a positive blood culture. Widal test showed a sensitivity of 33.3% and specificity of 76.3%. There was no association of any symptoms to antibody titres. There were three peaks when suspected cases reported to hospitals. More than 97% (n=447) of blood were sterile and Salmonella Typhi was isolated only in 1.3% (n=6). Only one isolate showed resistance to amoxicillin and nalidixic acid. Conclusion: Typhoid fever was not being diagnosed satisfactorily but over-diagnosed and treated clinically. Widal test should be replaced by more sensitive and specific tests or used cautiously with well-defined cut-off titres.