Birmingham, Ala. — Recent cases offer lessons about how some antifungal treatments can provoke drug-induced subacute cutaneous lupus erythematosus (DISCLE), as well as how to diagnose and treat onychomycosis and tinea capitis.

Pruritic rash

In one case, a 45-year-old Asian immigrant presented with a widespread, persistent pruritic rash.

With the fungal culture pending, the referring dermatologist diagnosed extensive tinea corporis, which apparently was confirmed by biopsy findings, including periodic acid-Schiff stain (PAS)-positive fungal hyphae in the stratum corneum, Dr. Elewski says.

Because the physician suspected Microsporum canis, which does not respond to oral terbinafine, he prescribed griseofulvin, along with an antifungal cream.

When the patient's rash worsened, he was referred to Dr. Elewski. Based on biopsy findings of superficial, deep and periadnexal lymphocytes and a vacuolar interface change (along with the patient's clinical presentation and serology results), she diagnosed DISCLE. Both griseofulvin and oral terbinafine can cause this disorder. The patient cleared upon discontinuation of griseofulvin.

Stubborn dermatitis

In another case, a patient with greasy scales on his eyelids, ears and scalp was diagnosed with seborrheic dermatitis. Topical desonide and ketoconazole initially worked, then failed, leading to a diagnosis of recalcitrant seborrheic dermatitis.

At this stage, Dr. Elewski says, "Dermatologists should consider an HIV test, and remember that seborrheic dermatitis can occur early in HIV, before the CD4 count gets very low." This patient was HIV-negative.

Dr. Elewski prescribed 2 percent ketoconazole foam. Before long, the patient cleared.

In other cases marked by a red, scaly face, symptoms can persist after appropriate treatments for seborrheic dermatitis, Dr. Elewski says.

In such cases, she says, "Think of rosacea, which often occurs concomitantly with seborrheic dermatitis. Sometimes the diagnosis is evident; sometimes it's not."

Dermatophytoma

Another case treated by Dr. Elewski involved a patient who presented with a history of thick, discolored toenails.

"When one sees dermatophytoma — a white patch or streak running down the nail — that implies a large collection of fungi analogous to a fungal abscess," she says.

In such cases, she recommends aggressive treatment with a minimum six months of terbinafine (three months on, one month off, followed by another three months on).

"I evaluate patients during these breaks from treatment and keep treating them until they're cured," Dr. Elewski says.

Other prognostic clues for onychomycosis include nail matrix involvement. "If the dermatophytoma approaches or hits the cuticle, that's a warning sign that one needs to be aggressive," she says.

Diabetic or immunocompromised patients also require aggressive treatment, even if they have minimal disease.

Adult tinea capitis

An 88-year-old female patient who presented with unexplained hair loss of more than 10 years serves as a reminder that tinea capitis doesn't just affect children, Dr. Elewski says.

Previous physicians had diagnosed her with bacterial folliculitis and pustular psoriasis of the scalp and prescribed treatments including oral and topical steroids and oral antibiotics.

Dr. Elewski performed a biopsy and fungal and bacterial cultures. Biopsy results came back first, indicating hyphae and an endothrix tinea capitis infection in scalp tissue samples.

After Dr. Elewski prescribed griseofulvin, she says, "The patient was cured and regrew all her hair."

Other women in whom Dr. Elewski has diagnosed tinea capitis have included a nurse and a schoolteacher.

"We usually see postmenopausal women with tinea capitis, not men, for several reasons. Women may go to a salon every week or two to get coiffed, and they may not wash their hair regularly between visits," Dr. Elewski says.

Accordingly, she says, "Think fungus when you see a woman with hair loss."

Disclosure: Dr. Elewski has performed clinical research and is a consultant for Schering-Plough, Novartis and Stiefel. She also is a clinical researcher for MediQuest.