A skin biopsy specimen from the lesion on the patient's neck showed a heavy infiltration of macrophages within the dermis, with overlying ulceration. The results of acid-fast bacilli stains were negative. Within the macrophages, there were numerous round organisms with occasional budding forms. The organisms measured 5 to 15 μm in diameter. The cell walls stained with periodic acid–Schiff (Figure 4), and the capsule stained with alcian blue. Cryptococcus neoformans was therefore diagnosed.
Plaques, Papules, and Nodules in a 40-Year-Old Man—Diagnosis. Arch Dermatol. 2006;142(7):921-926. doi:10.1001/archderm.142.7.921-e