The advent of fiberoptic endoscopy with biopsy has revolutionized procurement of specimens from deep sites. This has translated into more cytologic specimens whereby the material is limited and best handled by cytology laboratory staff. While the diagnosis of the pathologic process is of utmost importance, there is increasing expectation that the diagnosis be specific and accurate as not to require additional biopsy for initiation of treatment. This expectation has driven demand in immunohistochemical (IHC) and molecular studies conducted specifically on material processed as cytology specimens. The Clinical Laboratory Improvement Amendments of 1988 requires laboratories in the United States of America to verify the performance of patient tests. Due to varying laboratory practices with respect to validation of IHC assays, the College of American Pathologists introduced guidelines for analytic validation of IHC tests. These guidelines address how to perform validation by recommending the number of cases in the validation set, comparator concordance, and when to revalidate. The main thrust of the guidelines is based on formalin-fixed paraffin-embedded tissue with only one expert consensus opinion referring to validation of IHC tests on cytology specimens which delegates to the medical director, the determination of number of positive and negative cases to be tested. This article will outline how an academic center approaches validation of IHC studies performed on cytology cell block specimens using the College of American Pathologists guidelines. A stepwise approach from selection of antibodies to validate followed by building the validation panel and evaluating the stain results for concordance against the gold standard of histology tissue specimen will be described. A rationale for dealing with discordant results and future innovations will conclude the report.

Purpose: To detect the prevalence of genital infection caused by Chlamydia trachomatis in pregnant women and also to confirm the positive results using blocking antibody assay. Methods: Endocervical specimens were collected from 200 symptomatic and asymptomatic pregnant women attending the ANC OPD at M P Shah Medical College, Jamnagar. The samples were tested for presence of Chlamydia trachomatis antigen using the monoclonal antibody. Blocking antibody assay was used to further verify the positive results. Results: Out of 200 pregnant women, 38 (19%) were found positive for Chlamydia trachomatis antigen. Out of the 68 symptomatic patients, C. trachomatis antigen was detected in 26.4%. After verification of the positive samples 13.6% of the asymptomatic pregnant women were found to be harbouring the infection in their genital tract. Two (5.2%) out of the 38 positive samples, on verification with the blocking antibody assay, were found to be false positive by IDEIA, TM thus the specificity of the IDEIA TM being 94.8%. In patients with previous history of abortions, 27.7% were tested positive for C. trachomatis infection. Conclusions: Significant number of pregnant women shad C. trachomatis antigen in their endocervical canal, which can be easily diagnosed by this simple enzyme immuno assay having a specificity of 94.8%. Verification of positive results by antibody blocking assay can further improve the specificity of this non-culture test. Asymptomatic patients should also be screened for the infection. History of previous abortions places the patient at a higher risk for C. trachomatis infection thus such patients should be definitely tested for chlamydia infection. Key words: Chlamydia trachomatis, antigen, blocking antibody, pregnancyC. trachomatis infection, a prevalent sexually transmitted proved a definite role of C. trachomatis infection in adverse disease, is associated with complications like ectopic pregnancy outcome. [1][2][3][4] If not treated on time their newborns pregnancy, fallopian tube block and adverse pregnancy run a 20-40% risk of developing chlamydial conjunctivitis [7][8][9] outcome. [1][2][3][4] In majority of the women the infection with this and a 10-20% risk of developing chlamydial pneumonia. 7,9,10 organism is asymptomatic or with minimal symptoms. Studies from India have reported that 15% of young Therefore, screening of women at risk is highly recommended. asymptomatic women are positive for this infection. 11 In this study, an effort was made to detect C. trachomatis antigen Women at highest risk often have the least access to health from the endocervical specimens of the pregnant women and care facilities. Therefore there is a need for a rapid, simple and to verify the positive results with the antibody blocking assay accurate test to detect C. trachomatis infection, which can so as to achieve the most accurate results. be performed outside the laboratory setting when the patient is still in the clinical setting. Materials and Methods Detection of C. trachomatis infection b...

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