Typhidot test to detect IgG & IgM antibodies in typhoid fever.
ABSTRACT As typhoid fever is endemic in India, there is a continuing search for a simple test which can be carried out in small laboratories for an early and rapid diagnosis. We have evaluated the Typhidot test for this purpose.
The Typhidot test was carried out on coded sera according to the manufacturer's instructions. The test was performed on 30 Widal positive sera, 30 sera from blood culture positive patients, 60 Widal negative sera and 30 samples from patients whose blood culture grew Gram negative bacilli (GNB) other than Salmonella Typhi.
Typhidot test was positive for both IgG and IgM in 39 samples, IgM alone in 24 and IgG alone in 2. Of the 30 culture positive samples, 27 were positive by Typhidot. The Typhidot test gave a sensitivity of 100 per cent and specificity of 80 per cent when bacteraemic patients were analysed.
The Typhidot is easy to perform, and requires no special equipment or training of staff for interpretation of results. It will be a useful complementary test to blood culture and the Widal test in the diagnosis of typhoid fever.
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ABSTRACT: Typhoid continues to be one of the leading causes of morbidity and mortality in our country. Conventional methods of diagnosis are – gold standard blood culture and supportive widal test. We studied typhidot, a rapid serological test for diagnosis of typhoid fever and its usefulness for an early diagnosis, its sensitivity and specificity as compared to widal test. Methods : Typhidot test is an immunodot ELISA having an outer membrane protein specific for Salmonella typhi and separately identifies IgG and IgM antibodies. The study included 80 patients who presented with fever. Blood culture, widal test, and typhidot test were performed in all patients. Typhidot and widal tests were compared for sensitivity and specificity. Results : 56 patients out of 80 were clinically suspected to be cases of enteric fever (Gp-I), while 24 patients were non-typhoidal febrile illness (Gp-II). 38 patients (68%) of the Gp-I were positive for blood culture, 32 (57%) were widal positive, and 44(79%) were positive for typhidot test. Gp-II had all patients sterile on blood culture, 4 (17%) were widal positive, while 3 (12.5%) tested positive for typhidot. Amongst 38 culture positive cases in Gp-I, typhidot was positive in 35 patients, while widal was positive in 28 patients, giving sensitivity of 92% and specificity of 87.5% as compared to widal which had sensitivity of 74% and specificity of 83%. Conclusions : Typhidot test is an equally reliable, simple test that gives rapid diagnosis and can be helpful in early institution of therapy.
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ABSTRACT: In the absence of well-equipped laboratory infrastructure in many developing countries the accurate diagnosis of typhoid fever is challenging. Rapid diagnostic tests (RDT) with good performance indicators would be helpful to improve clinical management of suspected cases. We performed a systematic literature review and meta- analysis to determine the performance of TUBEX TF and Typhidot for the diagnosis of typhoid fever using PRISMA guidelines. Titles and abstracts were reviewed for relevance. Articles were screened for language, reference method and completeness. Studies were categorized according to control groups used. Meta-analysis was performed only for categories where enough data was available to combine sensitivity and specificity estimates. Sub-analysis was performed for the Typhidot test to determine the influence of indeterminate results on test performance. A total of seven studies per test were included. The sensitivity of TUBEX TF ranged between 56% and 95%, Specificity between 72% and 95%. Meta-analysis showed an average sensitivity of 69% (95%CI: 45-85) and an average specificity of 88% (CI95%:83-91). A formal meta-analysis for Typhidot was not possible due to limited data available. Across the extracted studies, sensitivity and specificity estimates ranged from 56% to 84% and 31% to 97% respectively. The observed performance does not support the use of either rapid diagnostic test exclusively as the basis for diagnosis and treatment. There is a need to develop an RDT for typhoid fever that has a performance level comparable to malaria RDTs.PLoS ONE 12/2013; 8(12):e81263. DOI:10.1371/journal.pone.0081263 · 3.53 Impact Factor
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ABSTRACT: For effective management of typhoid, diagnosis of the disease must be done with speed and accuracy. Laboratory diagnosis of typhoid fever requires isolation and identification of Salmonella enterica serotype Typhi. In many areas where the disease is endemic, laboratory capability is limited. Recent advances in molecular immunology have led to the identification of sensitive and specific markers for typhoid fever and technology to manufacture practical and inexpensive kits for their rapid detection. But their limitation paves way to continue to search for the ideal rapid tests to diagnose acute typhoid fever.African journal of microbiology research 09/2010; 4:1676-1677. · 0.54 Impact Factor