A 52 year old female with history of long standing uncontrolled diabetes mellitus on
treatment presents to OPD with white patches in the oral mucous membrane.
Scrapings obtained from the lesion showed gram positive budding yeast cells. Answer
the following:
What is the clinical diagnosis and the probable etiologic agent.
What are the other clinical manifestations caused by this organism.
Describe the laboratory diagnosis of this clinical condition.
What will be the appropriate line of treatment. (2+3+4+1)
Q110 marksEssays
Answer
Clinical diagnosis and probable etiologic agent: Oral candidiasis (thrush) — white oral mucosal patches with Gram-positive budding yeast cells on scraping, in a patient with uncontrolled diabetes (a recognized predisposing factor), is classical. Probable etiologic agent: Candida albicans.
Other clinical manifestations caused by Candida:
Vulvovaginal candidiasis — itching, curd-like discharge, particularly common in diabetics and pregnancy.
Oesophageal candidiasis — an AIDS-defining opportunistic infection at low CD4 counts.
Invasive/systemic candidiasis (candidaemia) — in critically ill/immunocompromised or catheterized patients.
Candidal onychomycosis/paronychia — nail and nail-fold infection.
Laboratory diagnosis
Direct microscopy — KOH mount/Gram stain of scraping showing budding yeast cells, with or without pseudohyphae.
Culture — on Sabouraud dextrose agar (SDA), giving cream-coloured, smooth colonies.
Germ tube test — rapid presumptive identification of C. albicans (germ tube formation in serum at 37°C for 2–3 hours).
Chlamydospore formation — on cornmeal-Tween 80 agar, confirmatory for C. albicans.
CHROMagar Candida — chromogenic medium for rapid presumptive speciation.
Blood culture — for suspected invasive/systemic disease.
Appropriate line of treatment: topical or oral azole antifungals (clotrimazole, fluconazole) for oral thrush, alongside optimizing glycaemic control in this diabetic patient (a key underlying predisposing factor that must be addressed to prevent recurrence).
