Open AccessImprovement of the newly developed latex agglutination test (Katex) for diagnosis of visceral lieshmaniasis
Author(s) -
Hatam Gholam Reza,
Ghatee Mohammad Amin,
Hossini Seyed Mohammad Hossein,
Sarkari Bahador
Publication year - 2009
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.20312
Subject(s) - latex fixation test , direct agglutination test , test (biology) , medicine , biology , immunology , serology , antibody , botany
: Different methods are available for diagnosis of visceral leishmaniasis (VL), among them the urine‐based antigen detection assay, latex agglutination test (Katex), is a recently developed one. The main drawback of the test is false‐positive reactivity in some of healthy individuals. The false positivity of the test can be removed by boiling the urine sample for 5 min before testing. In this study an attempt was made to improve Katex by removing unpleasant boiling process, which also decreases field applicability of the test. Methods : False‐positive and true‐positive urine samples were collected from VL patients and healthy individuals. Both samples were then treated by reagents including, sodium dodecyl sulfate, trichloroacetic acid, dithiothreitol (DTT), sulphosalicylic acid and also heating at 56°C. Results : Findings of this study showed that DTT pretreatment significantly reduced the rate of false‐positive reactivity of Katex where 73% of false‐positive urine samples changed to negative after DTT treatment. However, the DTT treatment reduced the rate of true positivity by 14%. Conclusion : These data indicate that DTT can be used to eliminate nonspecific reactivity in the Katex. This will improve the performance of Katex and make it a more convenient and field applicable test. J. Clin. Lab. Anal. 23:202–205, 2009. © 2009 Wiley‐Liss, Inc.