This Small Thing Causing Skin Bumps is About to Make a Comeback

Recently, temperatures across the country have been rising continuously, and friends visiting the dermatology department due to recurrent “red pimples” on the chest and back are gradually increasing. Everyone often faces the following troubles:

Many red rashes the size of rice grains appear for no reason, usually with white pustular changes at the top, basically painless, occasionally a little itchy.

Among them, some friends’ rashes will spread to the neck, jaw line, around the hairline, and even the scalp, lower back, abdomen,which greatly affects appearance.

In the past, friends who have had similar rashes during the summer and have visited the doctor may want to raise their hands to answer – is this “Malassezia folliculitis”?

Yes, this “red pimple” is different from the “pimple” (acne) that everyone knows well. It belongs to fungal folliculitis and requires standardized drug treatment after a clear diagnosis. If you do not understand this disease, it may be treated as acne or bacterial folliculitis, such as using topical adapalene ointment, fusidic acid ointment, and the treatment effect will be much worse.

This issue, let’s talk about what Malassezia folliculitis is that is prone to occur in summer.

What is Malassezia?

Malassezia is a lipophilic yeast that is part of the normal skin flora and is a very common commensal pathogenic fungus.

However, in areas where skin sebum secretion is abundant, such as when sweating increases, Malassezia may cause folliculitis reactions. (Because this fungus was previously classified under the genus Pityrosporum, it is also known as “Pityrosporum folliculitis”.)

Key point, two high-incidence factors for Malassezia folliculitis:

Based on this, if there is a history of long-term oral or topical antibiotics, corticosteroid hormones, and if the overall immune status is suppressed, Malassezia folliculitis is likely to occur.

For patients

What can it be confused with?

Usually appears on the chest, back, and shoulders, all in the form of single follicular papules or pustules (see the figure below), can have mild itching, usually no significant pain.

Secondly, the rash areas that may appear are the neck, the extensor side of the arms, and the forehead, chin, and both cheeks of the face..

However, note that Malassezia folliculitis usually does not appear on the central face. And these rashes, after recovery, usually do not leave much scar or pigment change.

Usually appears on the forehead, nose, mouth and cheeks,and the jaw line and neckcan also be affected,with closed and open comedones, red papules, pustules, and nodules as the main manifestations,may have various types of rashes (see the figure below).

Can cause persistent red or brown acne marks for several weeks, and severe cases may result in pitted scars.

Usually presents as a red, swollen, painful lump the size of a soybean or pea (see the figure below), existing alone.

Early on, it may be hard, and after 2-3 days, the lump softens, palpable fluctuation sense (a feeling like water waves when gently pressed), or the top gradually shows white pustular changes.

This issue requires topical or oral antibiotic treatment to ensure the rash subsides as soon as possible and to prevent the spread of infection. Severe cases of bacterial folliculitis may develop into deep abscesses, and in necessary cases, incision and drainage may be required.

Mainly seen in adults, usually manifested as pustules and red papules in the central face area.

Exacerbation may occur after exposure to special stimuli such as alcohol consumption, spicy food, prolonged sun exposure, and heat.

Usually characterized by small red papules around the mouth, nose, and orbital areas.
Young women are mainly affected, and the exacerbation is usually related to local
repeated use of steroids.

Diagnosing Malassezia folliculitis

What tests are needed?

For most experienced dermatology clinicians, an accurate clinical diagnosis can be made based on the morphology of the rash, the distribution characteristics of the rash, the timing of the rash, the history of previous treatments, and physical examination, and treatment can be guided.

However, in some cases where the rash is relatively few and cannot be fully differentiated by Malassezia folliculitis through history taking and physical examination, doctors will recommend that patients take the content from one or two folliculitis areas for a “fungal smear test” , that is, fungal microscopy.

This test is very convenient, by collecting superficial pustule scrapings to obtain smear samples, the collection process is very fast and basically painless.
Place the sample on a slide with potassium hydroxide, let it stand for a few minutes, and then observe under a microscope to get the report. If budding spores and curved short mycelia are detected under the microscope, a positive result can be reported.

However, because Malassezia may be present in normal human follicles, whether Malassezia folliculitis can be diagnosed usually requires a comprehensive judgment by the clinician based on the results of the fungal microscopy.

How to treat and prevent Malassezia folliculitis?

As repeatedly emphasized earlier, Malassezia folliculitis is a fungal folliculitis, so oral and topical antibiotics, as well as steroid ointments, are not indicated, and may even exacerbate the condition.

The usual first-line treatment plan is:

• Topical antifungal medications, such as azole antifungal drugs, selenium sulfide wash, etc.

• Oral antifungal medications, such as fluconazole, itraconazole.

Usually, after treatment, it can last for several months or even years without recurrence. However, the specific usage and course of treatment need to be prescribed by a dermatologist after diagnosis, which is not elaborated here.

For some immunocompromised individuals, or those in hot and humid environments for a long time, recurrence may still occur after treatment. Then, at the beginning of early summer, using selenium sulfide or ketoconazole wash 1-2 times a week to prevent recurrence
(may also be used long-term under the guidance of a doctor).