Paraffin-based immunohistochemistry in the evaluation of glomerular diseases in renal biopsies.
OBJECTIVE
To determine sensitivity and specificity of paraffin-based immunohistochemistry in the evaluation of glomerular diseases in renal biopsies using immunofluorescence as gold standard.


METHODS
Cross-sectional analytical study.


METHODS
Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi, from August 2008 to August 2009.


METHODS
Seventy renal biopsy specimens fulfilling the inclusion criteria for light microscopy and immunofluorescence during the study period were evaluated. Antibodies to immunoglobulins (IgG, IgA, and IgM) and components of complement system (C3) were applied on 70 formalin-fixed paraffin-embedded renal biopsy specimens previously classified by means of light microscopy and immunofluorescence (IF). Staining for these antibodies was recorded as positive and negative for immunohistochemistry (IHC) and IF in paired proportions presuming IF as gold standard test. The sensitivity, specificity, positive predicitive value and negative predicitive value of individual antibody were calculated.


RESULTS
Of 70 patients, mean age was 33 ± 18 years ranging from 2 to 80 years. Forty five (64%) were males and 25 (36%) were females. The sensitivity, specificity and predictive values of individual antibodies to IgG, IgA, IgM and C3 were very low and generally in the range of 40 - 60%.


CONCLUSIONS
The sensitivity, specificity and predictive values of immunohistochemistry on formalin-fixed paraffin-embedded renal biopsy specimens were very low and therefore, not suitable for evaluation of renal biopsies in current circumstances.
Department of Pathology, Combined Military Hospital, Quetta. usmanrathore78@gmail.com
Muhammad Usman
MU
Rathore
Muhammad Tahir
MT
Khadim
Sajid
S
Mushtaq
Muhammad
M
Atique
D001706:Biopsy; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D007674:Kidney Diseases / Q000473:pathology*; D008297:Male; D016612:Paraffin Embedding; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013194:Staining and Labeling