[Pityrosporum orbiculare in acneiform eruptions]

Area of Science:

• Dermatology
• Mycology
• Pathology

Background:

• Pityriasis versicolor is a common superficial fungal infection.
• Acneiform eruptions are characterized by pimple-like lesions.
• The association between pityriasis versicolor and acneiform eruptions is not well-established.

Purpose of the Study:

• To investigate the histological findings in patients presenting with acneiform eruptions in pityriasis versicolor predilection sites.
• To identify the etiological agents, specifically yeasts, present in these lesions.
• To discuss the potential pathogenicity of the identified fungi.

Main Methods:

• Case series describing six patients with acneiform eruptions.
• Histopathological examination of skin biopsies.
• Microscopic identification of yeasts within abscesses.

Main Results:

• Six patients exhibited acneiform eruptions in typical pityriasis versicolor areas.
• Histology revealed abscesses located below the acroinfundibulum.
• Yeasts with characteristics of Malassezia globosa (formerly Pityrosporum orbiculare) were identified within these abscesses.

Conclusions:

• Malassezia globosa may play a pathogenic role in certain acneiform eruptions.
• Further research is warranted to elucidate the direct causal relationship.
• This finding expands the spectrum of clinical presentations associated with Malassezia infections.