The diagnostic accuracy of three rapid diagnostic tests for typhoid fever at Chittagong Medical College Hospital, Chittagong, Bangladesh. Issue 10 (15th July 2015)

• Record Type: Journal Article
• Authors: Maude, Rapeephan R.; de Jong, Hanna K.; Wijedoru, Lalith; Fukushima, Masako; Ghose, Aniruddha; Samad, Rasheda; Hossain, Mohammed Amir; Karim, Mohammed Rezaul; Faiz, Mohammed Abul; Parry, Christopher M.; CMCH Typhoid Study Group; Sayeed, Abdullah Abu; Hasan, Uddin; Pan‐Ngum, Wirichada; van der Vaart, Thomas W.; Dutta, Asok Kumar; Mahmud, Nasir Uddin; Hero, Murad; Iqbal, Nafiz; Chaudhury, Zabeen; Nga, Tran Vu Thieu; Duy, Pham Thanh; Phat, Voong Vinh; Maude, Richard J.; Baker, Stephen; Wiersinga, W. Joost; van der Poll, Tom; Day, Nicholas P.; Dondorp, Arjen M.
• Is Part Of: Tropical medicine & international health. Volume 20:Issue 10(2015:Oct.)
• Page Start: 1376
• Page End: 1384
• Publication Date: 2015-07-15
• Subjects: Tropical medicine -- Periodicals; Public health -- Periodicals; 616.988
• DOI: 10.1111/tmi.12559
• Languages: English
• ISSNs: 1360-2276

Abstract

<abstract abstract-type="main" id="tmi12559-abs-0001"> <title>Abstract</title> <sec id="tmi12559-sec-0001" sec-type="section"> <title>Objective</title> <p>To determine the diagnostic accuracy of three rapid diagnostic tests (RDTs) for typhoid fever in febrile hospitalised patients in Bangladesh.</p> </sec> <sec id="tmi12559-sec-0002" sec-type="section"> <title>Methods</title> <p>Febrile adults and children admitted to Chittagong Medical College Hospital, Bangladesh, were investigated with Bact/Alert<sup>®</sup> blood cultures and real‐time PCR to detect <italic>Salmonella enterica</italic> Typhi and Paratyphi A and assays for <italic>Rickettsia</italic>, leptospirosis and dengue fever. Acute serum samples were examined with the LifeAssay (LA) Test‐it™ Typhoid IgM lateral flow assay detecting IgM antibodies against <italic>S. </italic>Typhi O antigen, CTKBiotech Onsite Typhoid IgG/IgM Combo Rapid‐test cassette lateral flow assay detecting IgG and IgM antibodies against <italic>S. </italic>Typhi O and H antigens and SD Bioline line assay for IgG and IgM antibodies against <italic>S. </italic>Typhi proteins.</p> </sec> <sec id="tmi12559-sec-0003" sec-type="section"> <title>Results</title> <p>In 300 malaria smear‐negative febrile patients [median (IQR) age of 13.5 (5–31) years], 34 (11.3%) had confirmed typhoid fever: 19 positive by blood culture for <italic>S. </italic>Typhi (three blood PCR positive) and 15 blood culture negative but PCR positive for <italic>S. </italic>Typhi in blood. The respective sensitivity and specificity of the three RDTs in patients using a composite reference standard of blood culture and/or PCR‐confirmed typhoid fever were 59% and 61% for LifeAssay, 59% and 74% for the CTK IgM and/or IgG, and 24% and 96% for the SD Bioline RDT IgM and/or IgG. The LifeAssay RDT had a sensitivity of 63% and a specificity of 91% when modified with a positive cut‐off of ≥2+ and analysed using a Bayesian latent class model.</p> </sec> <sec id="tmi12559-sec-0004" sec-type="section"> <title>Conclusions</title> <p>These typhoid RDTs demonstrated moderate diagnostic accuracies, and better tests are needed.</p> </sec> </abstract>