ABSTRACT
The objective of this study was to find a specific B-cell epitope of N-terminal region of antigen L-ESAT-6 from leprosy patients, healthy individuals and healthy nurses working for more than 10 years in the leprosy ward of Dr. A. Rivai Abdullah Leprosy Hospital, Palembang, Indonesia. Fifty subjects were enrolled in this study, comprising 10 subjects with LL type leprosy, 10 subjects with BB type leprosy, 10 subjects with TT type leprosy, 10 healthy nurses from leprosy ward and 10 healthy individuals as control group. The amino acid sequence of residues 11-36 of the N-terminal region of L-ESAT-6 were divided into a series of 18 peptides each consisting of 9-mer peptides with an overlap of 8-mers and an offset of one amino acid. The series of 18 peptides were synthesized in the form of biotinylated peptides and used to screen sera of 50 subjects using an indirect ELISA method. Our study identified at the N-terminal of L-ESAT-6, LEQCQES, VNELQG and IDALLE as epitope marker for LL and BB type of leprosy, epitope marker for TT type of leprosy and for (protective epitope marker) healthy nurses working for more than 10 years in the leprosy ward, respectively. These antigens can be used in immunochromatographic test for the early diagnosis of leprosy.
Subject(s)
Antigens, Bacterial/immunology , Bacterial Proteins/immunology , Epitopes, B-Lymphocyte/immunology , Leprosy, Tuberculoid/diagnosis , Leprosy, Tuberculoid/immunology , Mycobacterium leprae/immunology , Adolescent , Adult , Amino Acid Sequence , Antigens, Bacterial/chemistry , Bacterial Proteins/chemistry , Epitopes, B-Lymphocyte/chemistry , Female , Humans , Male , Middle Aged , Mycobacterium leprae/chemistryABSTRACT
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.
Subject(s)
Immunoassay/methods , Mycobacterium tuberculosis/immunology , Serologic Tests/methods , Tuberculin Test/methods , Tuberculosis, Pulmonary/blood , Adolescent , Adult , Bacteriological Techniques , Female , Humans , Male , Middle Aged , Mycobacterium tuberculosis/isolation & purification , Predictive Value of Tests , Sensitivity and Specificity , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/microbiologyABSTRACT
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).
