Clavispora lusitaniae and Ringworm-Like Eruptions in Immunocompetent Individuals
Clavispora lusitaniae can cause ringworm-like cutaneous eruptions in immunocompetent individuals, though this is exceptionally rare. The organism is primarily known as a cause of invasive fungal infections in immunocompromised hosts, but documented cutaneous presentations do exist in otherwise healthy patients.
Evidence for Cutaneous C. lusitaniae Infection
The strongest evidence comes from a documented case of cutaneous infection caused by C. lusitaniae in an immunocompetent pediatric patient 1. This case involved a one-and-a-half-year-old boy who presented with acute, severe inflammation around his left eyelid that failed to respond to antibacterial therapy. Scanning electron microscopy revealed hyphae and spores on the surface of crusty exudates that had penetrated into the tissue, with subsequent identification confirmed through 26S RNA gene and ITS region sequencing 1.
Critical Diagnostic Considerations
The key challenge is that C. lusitaniae cutaneous infections can clinically mimic dermatophyte infections (true ringworm), but they are fundamentally different organisms requiring different management:
- True ringworm is caused by dermatophyte fungi (Trichophyton, Microsporum, Epidermophyton species) affecting keratinized tissues 2, 3
- C. lusitaniae is a yeast (now classified as Clavispora lusitaniae) that can cause superficial infections mimicking dermatophytosis
The clinical presentation may be indistinguishable without laboratory confirmation, which is why definitive diagnosis requires:
- Direct microscopy showing yeast forms (not dermatophyte hyphae)
- Culture with characteristic yeast colony morphology
- Molecular identification via gene sequencing when available 1
Clinical Pitfalls to Avoid
- Do not assume all ringworm-like lesions are dermatophyte infections - failure to obtain fungal culture in treatment-resistant cases delays appropriate therapy
- Do not dismiss fungal etiologies in immunocompetent patients - while C. lusitaniae typically causes invasive disease in immunocompromised hosts, cutaneous infection can occur in healthy individuals 1, 4
- Do not rely solely on clinical appearance - other conditions including eczema can mimic tinea, and atypical fungal pathogens like C. lusitaniae can mimic dermatophytes 3
Treatment Approach
When C. lusitaniae cutaneous infection is confirmed:
- Topical azole antifungals are typically effective for localized cutaneous candidiasis (though specific data for C. lusitaniae cutaneous infection is limited)
- Systemic antifungal therapy may be required for extensive or treatment-resistant cases
- Echinocandins or fluconazole are standard for invasive Candida infections, though cutaneous infections generally respond to azoles 5
- Monitor for treatment response and consider alternative diagnoses if no improvement occurs
Important Caveats
The literature on C. lusitaniae causing superficial cutaneous infections in immunocompetent hosts is extremely limited, with most reports describing invasive disease (peritonitis, endophthalmitis, fungemia) in immunocompromised patients or those with indwelling devices 6, 4. The single well-documented case of cutaneous infection 1 demonstrates this is possible but emphasizes its rarity.
In practical terms: If you encounter a ringworm-like eruption that fails standard antifungal therapy for dermatophytes, obtain fungal culture and consider atypical pathogens including Candida species. The diagnosis of C. lusitaniae cutaneous infection should prompt evaluation for underlying immunocompromise or predisposing factors, even if the patient appears immunocompetent.