Mechanistic Insights into Calcium Oxalate Crystals in Aspergillosis of the Maxillary Sinus.

BACKGROUND

Aspergillus species can induce calcium oxalate crystal deposition, serving as an important diagnostic marker when typical fruiting bodies or ancillary techniques are unavailable. CASE PRESENTATION: We report a 35-year-old male with recurrent oroantral fistula and maxillary sinus opacity. Histopathology demonstrated septate hyphae and birefringent calcium oxalate crystals under polarized light, confirming non-invasive aspergillosis.Oxalosis, frequently linked to Aspergillus niger, contributes to mucosal destruction through vascular compromise and oxidative injury.

CONCLUSION

Recognition of these crystals is crucial for differentiating Aspergillus from other filamentous fungi and underscores their diagnostic, pathogenic, and prognostic significance in sinonasal disease when conventional molecular methods are not employed.