Species identification of Candida isolates obtained from oral lesions of HIV infected patients.

A total of 60 patients suspected to have AIDS with oral lesions suggestive of oral candidiasis were studied. Candida species were isolated from 50 patients. Candida albicans was the commonest isolate (70 %) followed Candida parapsilosis(15%), Candida glabrata (7.5%) and Candida tropicalis (5%) respectively. Candida dubliniensis was isolated from a single case only. Though the reports from developed countries show more prevalence of the novel species Candida dubliniensis, in our study it was isolated in a single case. All the patients were treated successfully with oral fluconazole for 7 days except for the patients from which Candida glabrata was isolated, who were treated with Amphotericin B.

Introduction

Oral candidiasis is the most common opportunistic infection in patients with HIV infection in India.[1] Various studies have shown increasing incidence of candidiasis in HIV infected persons.[2-5] In the recent past, there have been increasing reports implicating the non-albicans species of Candida in oropharyngeal candidiasis.[2-5] We studied the prevalence and clinical and microbiological variations of oral candidiasis in HIV infected persons.

The study was conducted in the Department of Microbiology, Lokmanya Tilak Municipal Medical College and General Hospital, Mumbai, from July 2005 to June 2008. A total number of 61 HIV seropositive patients with oral lesion/lesions suggestive of oral candidiasis, which were referred from the Department of Medicine and Dermatology, were included in the study of which 46 were males and 15 were females (male: female ratio of 3:1). The age group ranged between 20 and 60 years (mean age 40 years). Most common clinical presentation was pseudomembranous lesions [Figure 1] in 50 cases, followed by erythematous lesions in 10 cases. Candida species were isolated from 40 patients, demonstrating a prevalence of 66.57%. All the patients from whom Candida species were isolated presented with a burning sensation, dysphagia, and odynophagia suggestive of esophageal involvement. Candida albicans was the most common isolate 70% (28/40), followed by C. parapsilosis 15% (6/40), Candida tropicalis 5% (2/40), and C. glabrata 7.5% (3/40), while C. dubliniensis [Figure 2] was isolated in a single case (2.5%). Oropharyngeal candidiasis, the most common opportunistic infection in patients with HIV, occurs in as many as 90% of HIV infected persons at some point during the course of disease.[6] The prevalence of oral candidiasis in HIV infected patients in India varies between 41%[4] and 85%.[1] In India, it is the most common manifestation in HIV infected persons.[1-5] Though C. albicans is the most common cause of oral candidiasis, certain non-albicans species such as C. parapsilosis, C. glabrata, C. tropicalis, C. kefyr and new species C. dubliniensis[7] are now encountered. This study shows substantial increase in isolation of non-Candida albicans species (30%) as reported earlier by Kaviarasan et al.[1] (20.2%), and the new species i.e. C. dubliniensis is also isolated from HIV seropositive cases in this study.

Figure 1

Clinical photograph showing typical presentation of oral thrush (white curdy patches in dorsum of tongue)

Figure 2

LPCB mount of colonies on tobacco agar showing clustering of chlamydospores at the tip of short pseudohyphae suggestive of Candida dubliniensis