A Comparative Study of the Performance of Typhoid Diagnostic Tests among Suspected Patients at the University of Cape Coast Hospital, Ghana

Abstract

Introduction: the World Health Organization recommends that the gold standard for diagnosing typhoid fever is the use of blood cultures. However, under real-world conditions in low-resource settings, there are lack of culture facilities as well as expertise, and usually, patients report late after prior antibiotic exposure. This study sought to evaluate the performance of typhoid rapid diagnostic tests, blood, and stool cultures as well as polymerase chain reaction (PCR) under such settings. Methods: This cross-sectional study involved the use of blood and stool samples from 400 consenting outpatients suspected of typhoid fever by attending clinicians at the University of Cape Coast Hospital, Ghana. Results: out of the 400 participants, 171 (42.8%) tested positive to at least one of the RDTs. Even though many of the participants had a history of fever, all of them were afebrile as none presented with a temperature of 380C and above. There was a high (48.0%) history of antibiotic use within two weeks before presentation. No participant was a culture or PCR positive for S. typhi and paratyphi. However, in 7(1.8%) participants, other salmonella species were detected by PCR. Also, citrobacter and proteus vulgaris were cultured in 13(3.3%) and 10(2.5%) participants respectively using stool samples. In blood samples, there was a 7(1.8%) growth of Staphylococcus aureus. Conclusion: under real-world conditions where patients usually present without typical symptoms such as high temperatures probably after prior antibiotic use, cultures and PCR perform poorly. There is therefore a need for further studies aimed at improving the yields of these important diagnostic tests in such settings.