The immunoserological diagnosis of tuberculosis: a comparison of two tests.

A comparative study of the diagnostic value of the ICT-TB test and the TB-Dot test, based on laboratory examination, was carried out in 39 patients suffering from sputum positive pulmonary tuberculosis (25 males and 14 females, aged 16-50 years) and in 48 patients (27 males and 21 females, aged 17-55 years) suffering from non-tuberculosis pulmonary diseases, that had attended the Tembagapura Hospital and the TB Control Health Center Timika-Mimika, Papua. The diagnostic sensitivity of the ICT-TB test was 87.18%, the diagnostic specificity was 81.25%, the diagnostic positive predictive value was 79.07%, the negative predictive value was 88.64%, and the diagnostic efficiency was 83.91%. The diagnostic sensitivity of the TB-Dot test was 93.31%, the diagnostic specificity was 95.83%, the diagnostic positive predictive value was 94.74%, the negative predictive value was 93.85%, and the diagnostic efficiency was 94.25%. The results of the statistical analysis of the data obtained in this study revealed that the diagnostic specificity, the diagnostic positive predictive value and the diagnostic efficiency of the TB-Dot test were significantly higher (p < 0.05) than those of the ICT-TB test. However, the diagnostic sensitivity and the negative predictive value of both tests did not differ significantly (p > 0.05). Viewed from the point of their practicability, it can be justified that the ICT-TB test is a very practicable test, which needs only 15 minutes and does not require special instruments to perform the test, but is more expensive than the TB-Dot test. On the other hand, though the TB-Dot test is not very practicable and relatively time consuming, it has a significantly higher degree of diagnostic value and is much cheaper when compared to the ICT-TB test.

Comparison of the diagnostic value of local Widal slide test with imported Widal slide test.

A laboratory study comparing the Widal slide agglutination test using local antigens produced by Mekar Jaya Diagnostica (SAT-MJD) with imported antigens (Murex, Abbott) was carried out on 55 sera of typhoid fever patients with positive blood culture and 56 sera of non-typhoid febrile patients. The SAT-MJD antigens consisted of a mixture of 5 different phage-types of S. typhi dominantly found in Indonesia. This study revealed the following results: the diagnostic sensitivity of local and imported antigens was 83.93%, the diagnostic specificity of local antigens was higher than the imported antigens ie 82.14% compared with 64.28%, the diagnostic efficiency of local antigens was 82.88% compared with 73.87% of the imported antigens. The diagnostic positive and negative predictive values of the local antigens were 80.70% and 83.63%, respectively. The imported antigen revealed diagnostic positive and negative predictive values of 69.69% and 80%, respectively. The diagnostic specificity and efficiency of local antigens were significantly different (p < 0.02 and p < 0.05) from the imported antigens. The local antigens have some advantages. There was no variation in within-run and between-day test, compared with a 6.6% variation shown by the imported antigen. The test results obtained 5 minutes after mixing the serum with antigens reduced the possibility of false-positive and false-negative results. The cost of local antigens is lower than the imported antigens. Based on these data, the Widal SAT-MJD has a reliable diagnostic value and can be used in small laboratories, such as primary health centers (Puskesmas).