Fungal acne vs acne — how to tell them apart

When acne creams and antibiotics have not moved the bumps, and the bumps itch on top of it, the next question is usually what else to put on. If acne medication has not helped and the bumps itch, it may not be acne but Malassezia folliculitis. The two are hard to tell apart by eye, and a microscope makes the call. Below are three signs you can check at home and the test to ask for.

What is Malassezia folliculitis?

Malassezia folliculitis is an inflammation of the hair follicles caused by an overgrowth of Malassezia, a yeast, and is often called fungal acne. Malassezia lives on everyone's skin as part of the normal flora, so its presence alone is normal. Malassezia folliculitis is often misdiagnosed as acne, and the two conditions can coexist in the same person (Paichitrojjana & Chalermchai, 2022).

How to self-check for Malassezia folliculitis

Among patients newly diagnosed with acne, 28.8% met the microscope criterion for Malassezia folliculitis, and one in four (24.7%) had both conditions (Paichitrojjana & Chalermchai, 2022).

Itching, bumps on the scalp or hairline, and bumps on the upper back were far more common in patients with Malassezia folliculitis (Paichitrojjana & Chalermchai, 2022). The odds ratios, a statistic that compares the two groups, were 7.38, 8.89 and 9.17.

How do clinics confirm Malassezia folliculitis?

Malassezia folliculitis is confirmed by extracting the contents of a pustule or bump, staining the smear and counting spores under a microscope. In Korean dermatology clinics, the basic test for fungus is the KOH test (Korean Dermatological Association).

Of patients whose doctors suspected Malassezia folliculitis by eye, 57.1% had yeast confirmed under the microscope, so Malassezia folliculitis is not diagnosed by eye alone (Yong et al., 2021).

What medicine is used for Malassezia folliculitis?

The medicine used is an antifungal. In a trial comparing oral itraconazole with a placebo, 84.6% of the antifungal group had cleared or markedly improved, against 8.3% of the placebo group (Parsad et al., 1999). The itraconazole used in that trial is a prescription drug in Korea, and its approved indications there do not list this folliculitis, so whether to prescribe it is usually the doctor's decision (Korea Pharmaceutical Information Center).

In short, a microscope comes before the next product

Malassezia folliculitis is a yeast overgrowth in the follicle, so it calls for different medicine than acne. 28.8% of acne patients met the microscope criterion (Paichitrojjana & Chalermchai, 2022). The three signs, itching, scalp and upper back, are a self-check, not a certainty.

If you suspect Malassezia folliculitis, get a microscope test from a dermatologist before changing products. If the test finds no fungus in your bumps, the next read is Comedones that won't clear — why exfoliating misses them.

One step today

• In front of a mirror, check three things: itching, bumps on the hairline or scalp, and bumps on the upper back. These are the three signs most strongly linked with Malassezia folliculitis (Paichitrojjana & Chalermchai, 2022). If any one applies, ask for a microscope test at your next dermatology visit; if none does, check again when itching appears.
• At your next appointment, ask: "Could you do a KOH test, looking at the contents of a pustule under the microscope to check for fungus?" Mention that acne medication did not change anything. Of patients suspected by eye, 57.1% were confirmed (Yong et al., 2021). The test is quick (Korean Dermatological Association), and whether to add an antifungal is the doctor's decision once the result is in. If the result is negative and the three signs remain, you can ask for a stained smear (see the FAQ below).
• Until the result is in, add no new products, and keep your cleanser and moisturizer (a moisturizer with barrier ingredients such as ceramides or panthenol) as they are. We found no research yet showing that cosmetics with antifungal ingredients reduce Malassezia folliculitis in people.