A case of primary cutaneous Cryptococcus neoformans infection

Area of Science:

• Mycology
• Infectious Diseases
• Dermatology

Background:

• Cryptococcosis is caused by encapsulated yeasts, with inhalation being the most common route.
• Primary cutaneous cryptococcosis is an exceptionally rare form of this fungal infection.
• Immunocompromised individuals, such as those on long-term corticosteroids, are at higher risk.

Observation:

• A 61-year-old woman on prednisone for rheumatoid arthritis presented with a worsening thigh lesion.
• Initial treatments failed, and the lesion ruptured, accompanied by fever.
• Microbiological analysis revealed secondary bacterial infections, but skin biopsy and culture confirmed Cryptococcus neoformans.

Findings:

• Histopathology and culture are crucial for diagnosing primary cutaneous cryptococcosis.
• Mass spectrometry identified the pathogen as Cryptococcus neoformans serotype A.
• The patient responded well to oral fluconazole and topical nystatin, achieving near-complete healing.

Implications:

• Primary cutaneous cryptococcosis lacks typical clinical signs, making diagnosis challenging.
• Culture and histopathology are the gold standards for definitive diagnosis.
• Fluconazole is the recommended treatment, and this diagnosis should be considered for unexplained skin ulcers in at-risk patients.