Study of Salivary Candida in HIV Seropositive Patients, South India

Objectives: Candida is a normal human oral cavity commensal that acquires pathogenicity when the host immune system is compromised as in HIV infection and is a marker of immunosuppression. Genus Candida includes 150 asporogenous yeast species, of the class Deuteromycetes. The aim of this study is to isolate, identify, speciate and compare candida in symptomatic HIV seropositive (SHP), asymptomatic HIV seropositive (AHP), symptomatic presumed HIV seronegative (SHN), and normal controls (NC).Methods: 207 subjects from RAGAS-YRG CARE. Chennai South India. Sample collection: Oral rinse sampling technique. Tests for species identification: Germ tube technique (GTT), Carbohydrate assimilation test (CAT), Cornmeal agar morphological test (CAMT), and CHROMagar Candida®.Result: C.albicans was the most commonly isolated candidal subtype in SHP and AHP groups using all three laboratory techniques followed by C.tropicalis, C.parapsilosis (only in SHP). C.tropicalis was seen more commonly in the seronegative (32%) group when compared to seropositive group (9.6%). The patients in SHP group were severely immunocopromised, with CD4+ lymphocytes ≤ 50 cells/mm3 (44%) which contributed to the increased CFU in these patients. Conclusion: Though mixed colonies of C.albicans and C.tropicalis were seen in SHP, C.albicans was the most commonly isolated subtype in the immunosuppressed group. CAT was considered the gold standard for Candida identification at the species level. On comparing the species identified by various techniques, CAT and CAMT test could identify C.parapsilosis in addition to the other candidal species.