Perbandingan Hasil Pemeriksaan Widal dan Tubex-TF Pada Pasien dengan Dugaan Demam Tifoid di RSUD Haji Makassar

Abstract

Typhoid fever is a systemic infectious disease caused by the bacteria Salmonella typhi and paratyphi A, B, and C, and remains a public health problem in developing countries, including Indonesia. The Widal test has limitations in the form of cross-reactivity and interpretation that is highly dependent on the cut-off titer and the local epidemiological context; therefore, a comparative testing method such as Tubex-TF is needed, although evidence regarding the comparison of results between the two methods remains limited. This study aimed to compare the results of the Widal and Tubex-TF tests in patients with suspected typhoid fever at the Haji Makassar Regional General Hospital. This was a descriptive observational study using a cross-sectional design involving 8 patients clinically diagnosed with typhoid fever by physicians, with serum or plasma samples obtained via accidental sampling. The Widal test was performed qualitatively and semi-quantitatively with a positive cutoff titer of ≥1/160, while the Tubex-TF test was conducted using the Inhibition Magnetic Binding Immunoassay method. Of the 8 samples, the Widal test yielded negative results in 2 samples (25%) and positive results in 6 samples (75%), while the Tubex-TF test yielded a borderline result in 1 sample, a weak positive in 4 samples, and a positive result in 3 samples. Borderline results were treated as negative; the proportion of positive results was 87.5% (7/8). The numerically higher proportion of positive Tubex-TF results compared to the Widal test in this preliminary study indicates the potential of Tubex-TF as a complementary test; however, further research with a clear gold standard and a larger sample size is needed before it can be concluded as an alternative diagnostic method.

Keywords: Sensitivity, Widal, Tubex-TF, Typhoid Fever