“EVALUATION OF PERIODIC ACID SCHIFF STAIN VERSUS POTASSIUM HYDROXIDE MOUNT FOR DIAGNOSIS OF FUNGAL INFECTIONS.”
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Keywords
KOH Mount, Fungus, PAS (Periodic Acid Schiff)
Abstract
: Fungal infections impact over 57 million people in India, highlighting the need for early and accurate diagnosis, particularly in immunocompromised individuals. This study compares the diagnostic efficacy of KOH mount, PAS staining, and fungal culture—assessing their sensitivity and specificity—to guide optimal approaches for timely and effective management.
Aim :To compare diagnostic accuracy of KOH mount versus PAS stain for fungal diagnosis.
Materials and Methods : A cross-sectional study was conducted over a period of six months on 40 clinical samples at a tertiary care centre, with each sample undergoing KOH mount, PAS staining, and fungal culture. Sensitivity and specificity for KOH mount and PAS stain were evaluated in comparison with the gold standard method, fungal culture.
Results : Out of 40 cases, 15% tested positive by all three methods. Isolated positivity was 7.5% each for PAS and KOH, and 5% for culture. PAS showed higher sensitivity (75%) and accuracy (82.5%) compared to KOH (58.33% and 77.5%, respectively). Both tests had equal specificity (85.71%).
Conclusion: PAS staining showed higher sensitivity, while KOH mount demonstrated good specificity compared to fungal culture, which remains the gold standard. A combined approach using PAS, KOH, and culture enhances diagnostic accuracy for fungal infections. Larger studies with molecular methods are recommended to further optimize diagnostic strategies.
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Dr. Aghara Shradhdha S.
(Final year Post graduate, Department of pathology, Sri Venkateswara Medical college, Tirupati)
Dr. S. Rajasekhar Reddy
(Associate Professor, Department of Pathology, Sri Venkateswara Medical College, Tirupati)
Dr. B. Mallikarjun
(Assistant Professor, Department of Pathology, Sri Venkateswara medical College, Tirupati)
Dr. P. Swarnalatha
(Associate Professor, Department of Pathology, Sri Venkateswara Medical College, Tirupati)
Dr. G. Indrani
(Professor and HOD, Department of Pathology, Sri Venkateswara Medical College, Tirupati)
Dr. N. Srivani
(Associate Professor, Department of Microbiology, Sri Venkateswara Medical College, Tirupati)