A young adult presents with hypopigmented macules on the upper trunk that fail to tan with sun exposure. Skin scraping examined under KOH shows short hyphae and clusters of yeast cells described as 'spaghetti and meatballs'. The causative organism grows on Sabouraud dextrose agar only when supplemented with olive oil or other long-chain fatty acids. What is the causative organism?

• A Pityrosporum ovale
• B Candida albicans
• C Trichophyton rubrum
• D Malassezia furfur ✓

Explanation

Malassezia furfur (formerly Pityrosporum ovale) causes pityriasis versicolor (tinea versicolor) and characteristically appears as short hyphae with yeast clusters resembling spaghetti and meatballs on KOH mount. It is lipophilic and requires long-chain fatty acids for growth on standard media. Option A is an outdated synonym for the same organism but D is the currently accepted name in medical mycology texts.

Reference: Jawetz, Melnick, & Adelberg's Medical Microbiology, 28th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.