Clinical and microbiological profile of Candida isolates from oral candidiasis in patients undergoing radiotherapy for head and neck malignancy

Abstract

Objective: To study the clinico-microbiological profile of oral candidiasis in head and neck squamous cell cancer (HNSCC) patients undergoing curative radiotherapy (cRT). Methods: Patients undergoing cRT and developing oral candidiasis were enrolled. Clinical features such as pain and xerostomia were recorded. Candida isolates from lesions were speciated using CHROMagar (Himedia Inc.), and antifungal susceptibility was determined using microbroth dilution (MBD). Patients were followed up to study the clinical course of infection. Results: Of the 100 patients undergoing cRT, 79 developed oral candidiasis. Median duration to development of infection was 4 weeks (range: 1-6.5 weeks). Mucositis was observed in 76 (96.2%) and xerostomia in 53 (67.1%) patients; 61 patients (77.2%) had symptoms attributable to candidiasis. However, there was no correlation between severity of infection and mucositis (p=0.84) or xerostomia (p=0.51). Candida albicans was the most frequent (47 patients, 59.4%) isolate, followed by Candida tropicalis (23 patients; 29.1%). All isolates were sensitive to nystatin, but fluconazole resistance/dose-dependent susceptibility was noted in 26 (32.9%) isolates. Both Candida krusei and two of four Candida glabrata isolate exhibited fluconazole resistance. All patients received treatment for Candidiasis. On follow-up, 1 month after cRT, oral candidiasis resolved with gradual recovery of mucositis in all patients. Conclusion: Candida albicans was the most common cause of oral Candidiasis in HNSCC cRT, and all isolates were susceptible to nystatin in-vitro. All lesions resolved with recovery from mucositis. In addition, as no patient developed systemic candidiasis, it appears that oral candidiasis though troublesome is curable with treatment.