Prevalence and characterization of opportunistic candidal infections among patients with pulmonary tuberculosis

Although Candida albicans remains the most common cause of human candidiasis, the frequency of infection attributed to other members of the genus is also increasing. Hence, the present study was carried out to know the prevalence of opportunistic candidal infection in tuberculosis, and if positive, the species of Candida that is most commonly associated.

The present study comprised sixty pulmonary tuberculosis patients who were divided into (1) fresh or untreated group, (2A) chronic or treated group having no complications and (2B) having complications, comprising twenty patients each, respectively. The collected sputum samples were initially stained with Ziehl-Neelsen stain for confirmation of presence of tubercle Bacilli. Primary isolation was done on Sabouraud Dextrose Agar (SDA). The candidal colonies were confirmed microscopically for the presence of pseudohyphae. Further speciation of the positive candidal samples was carried out using ChromAgar.

The total fungal prevalence among 60 patients with pulmonary tuberculosis on SDA was 33 (55%) Candida and 3 (5%) Aspergillus. The prevalence of different candidal species on ChromAgar showed C. albicans as the predominant one, followed by Candida tropicalis and Candida krusei. Freshly diagnosed or untreated group was less commonly associated with pulmonary mycoses than chronic or treated group. The prevalence of Candida had increased with treatment, duration and age, and it was more in males than females.

The present study confirms the phenomenon of opportunistic candidal infections in pulmonary tuberculosis patients. Rapid and reliable identification of Candida species is essential as they differ in their virulence and sensitivity to antifungal drugs.