Evaluation of H&E, PAS, and GMS Stains Compared with Culture and PCR in Fungal Infection Diagnosis: A Systematic Review

Background: Fungal infections are increasingly recognized as major causes of morbidity and mortality, especially among immunocompromised patients. Timely and accurate diagnosis is critical for effective management. Histopathological stains such as Hematoxylin and Eosin (H&E), Periodic Acid-Schiff (PAS), and Gomori Methenamine Silver (GMS) are widely used for tissue-based fungal detection, yet their diagnostic accuracy compared with culture and polymerase chain reaction (PCR) remains variable.

Aim: To systematically evaluate the diagnostic performance of H&E, PAS, and GMS stains in detecting fungal infections, and to compare their efficacy with culture and PCR as reference standards.

Methods: A systematic search of PubMed, Scopus, and Google Scholar databases was conducted for studies published between 2000 and 2025. Eligible studies compared one or more histopathological stains with culture and/or PCR in human tissue specimens. Data on sensitivity, specificity, and diagnostic concordance were extracted and analyzed qualitatively following PRISMA guidelines.

Results: Twenty-seven studies (n = 2,345 samples) met inclusion criteria. GMS demonstrated the highest sensitivity (80–98%) for fungal detection, followed by PAS (70–90%) and H&E (50–80%). Specificity across stains was consistently above 85%. Culture showed variable sensitivity (40–70%) and longer turnaround time, while PCR achieved superior accuracy (sensitivity >95%, specificity >98%) even in formalin-fixed paraffin-embedded (FFPE) tissues. Combining histopathology with PCR improved diagnostic yield to over 98%.

Conclusion: While GMS remains the most reliable histopathological stain for detecting fungal elements, PCR provides the highest diagnostic precision and species-level identification. Integration of histopathology, culture, and molecular methods ensures optimal accuracy and rapid diagnosis of fungal infections, particularly in critically ill or immunocompromised patients

Fungal infection, Histopathology, H&E, PAS, GMS, Culture, PCR, Diagnostic accuracy.