[Malassezia folliculitis: characteristics and therapeutic response in 26 patients]

Clinical characteristics and treatment outcomes of Pityrosporum folliculitis in immunocompetent patients

Pityrosporum folliculitis (PF) is a fungal acneiform disease of the hair follicles that often presents with pruritic papules and pustules on the upper body and face. This condition is commonly mistaken for acne vulgaris and can be distinguished from bacterial acne by the presence of fungal spores in the follicular lumen. Although studies have been performed to describe PF in cohorts, little work has been done to aggregate these data. Thus, the goal of this review is to describe the clinical characteristics and treatment outcomes of PF in immunocompetent patients. PubMed, Web of Science, and Embase were searched using the terms "Pityrosporum folliculitis" or "Malassezia folliculitis." All cohorts reporting PF characteristics in patients classified as immunocompetent were reviewed. A total of 15 studies were included. Majority of patients were male (64%) with the average age of presentation of 24.26 years. The most common locations of lesions were the chest (70%) and back/shoulders (69.2%). Pruritus was reported by the majority of patients (71.7%). Additionally, 40.5% of patients reported a history of unsuccessful treatment regimens. Treatment was most successful with an oral antifungal (92%), followed by a topical antifungal (81.6%). In conclusion, majority of patients with PF were younger males. Many patients were primarily treated incorrectly, suggesting the importance of proper diagnosis. PF may be distinguishable from acne vulgaris by the presence of pruritus or suggested when a new acneiform eruption develops following antibiotic therapy or immunosuppression. When properly diagnosed, majority of cases of PF achieve complete response with oral or topical antifungals.

Position statement: Recommendations on the diagnosis and treatment of Malassezia folliculitis

Malassezia is a lipophilic yeast that is a part of the human mycobiome. Malassezia folliculitis appears when the benign colonization of the hair follicles, by the Malassezia yeasts, becomes symptomatic with pruritic papules and pustules. Although Malassezia folliculitis is common in hospital departments, diagnosing and treating it varies among dermatologists and countries. The European Academy of Dermatology and Venereology Mycology Task Force Malassezia folliculitis working group has, therefore, sought to develop these recommendations for the diagnosis and management of Malassezia folliculitis. Recommendations comprise methods for diagnosing Malassezia folliculitis, required positive findings before starting therapies and specific treatment algorithms for individuals who are immunocompetent, immunocompromised or who have compromised liver function. In conclusion, this study provides a clinical strategy for diagnosing and managing Malassezia folliculitis.

Malassezia: Zoonotic Implications, Parallels and Differences in Colonization and Disease in Humans and Animals

Malassezia spp. are commensals of the skin, oral/sinonasal cavity, lower respiratory and gastrointestinal tract. Eighteen species have been recovered from humans, other mammals and birds. They can also be isolated from diverse environments, suggesting an evolutionary trajectory of adaption from an ecological niche in plants and soil to the mucocutaneous ecosystem of warm-blooded vertebrates. In humans, dogs and cats, Malassezia-associated dermatological conditions share some commonalities. Otomycosis is common in companion animals but is rare in humans. Systemic infections, which are increasingly reported in humans, have yet to be recognized in animals. Malassezia species have also been identified as pathogenetic contributors to some chronic human diseases. While Malassezia species are host-adapted, some species are zoophilic and can cause fungemia, with outbreaks in neonatal intensive care wards associated with temporary colonization of healthcare worker’s hands from contact with their pets. Although standardization is lacking, susceptibility testing is usually performed using a modified broth microdilution method. Antifungal susceptibility can vary depending on Malassezia species, body location, infection type, disease duration, presence of co-morbidities and immunosuppression. Antifungal resistance mechanisms include biofilm formation, mutations or overexpression of ERG11, overexpression of efflux pumps and gene rearrangements or overexpression in chromosome 4.

Malassezia (Pityrosporum) Folliculitis Masquerading As Recalcitrant Acne

Malassezia (Pityrosporum) folliculitis is a relatively common skin infection that affects the hair follicles. The condition is characterized by monomorphic perifollicular skin lesions and itching without comedones. Malassezia folliculitis significantly resembles acne vulgaris and steroid acne but is subtly distinct and managed differently. Oral antifungals are preferred for the treatment and result in a dramatic improvement in the disease condition. Early recognition of the disease is important for satisfactory clinical outcomes. This case reports about a female in the reproductive age group, who took multiple treatments for erythematous papular lesions on her face with a provisional diagnosis of acne vulgaris. After observing no improvement over the last three months, she visited the Dermatology clinic at a tertiary care hospital. A diagnosis of Malassezia folliculitis was considered and confirmed on microscopic examination and oral and topical antifungals were prescribed. She reported significant improvement in her skin lesions after two weeks of treatment.

Critical synthesis of available data in Malassezia folliculitis and a systematic review of treatments

Folliculitis is an inflammatory process involving the hair follicle, frequently attributed to infectious causes. Malassezia, an established symbiotic yeast that can evolve to a skin pathogen with opportunistic attributes, is a common source of folliculitis, especially when intrinsic (e.g. immunosuppression) or extrinsic (high ambient temperature and humidity, clothing) impact on the hair follicle and the overlying skin microenvironment. Our aim was to critically review the pathophysiology and clinical characteristics of Malassezia folliculitis, to describe laboratory methods that facilitate diagnosis and to systematically review treatment options. Malassezia folliculitis manifests as a pruritic, follicular papulopustular eruption distributed on the upper trunk. It commonly affects young to middle-aged adults and immunosuppressed individuals. Inclusion into the differential diagnosis of folliculitis is regularly oversighted, and the prerequisite-targeted diagnostic procedures are not always performed. Sampling by tape stripping or comedo extractor and microscopic examination of the sample usually identifies the monopolar budding yeast cells of Malassezia without the presence of hyphae. However, confirmation of the diagnosis with anatomical association with the hair follicle is performed by biopsy. For systematic review of therapies, PubMed was searched using the search string "(malassezia" [MeSH Terms] OR "malassezia" [All Fields] OR pityrosporum [All Fields]) AND "folliculitis" [MeSH Terms] and EMBASE was searched using the search string: 'malassezia folliculitis.mp OR pityrosporum folliculitis.mp'. In total, 28 full-length studies were assessed for eligibility and 21 were selected for inclusion in therapy evaluation. Conclusively Malassezia folliculitis should be considered in the assessment of truncal, follicular skin lesions. Patient's history, comorbidities and clinical presentation are usually indicative, but microscopically and histological examination is needed to confirm the diagnosis. Adequate samples obtained with comedo extractor and serial sections in the histological material are critical for proper diagnosis. Therapy should include systemic or topical measures for the control of the inflammation, as well as the prevention of recurrences.

Malassezia-Associated Skin Diseases, the Use of Diagnostics and Treatment

Yeasts of the genus, Malassezia, formerly known as Pityrosporum, are lipophilic yeasts, which are a part of the normal skin flora (microbiome). Malassezia colonize the human skin after birth and must therefore, as commensals, be normally tolerated by the human immune system. The Malassezia yeasts also have a pathogenic potential where they can, under appropriate conditions, invade the stratum corneum and interact with the host immune system, both directly but also through chemical mediators. The species distribution on the skin and the pathogenetic potential of the yeast varies between different Malassezia related diseases such as head and neck dermatitis, seborrheic dermatitis, pityriasis versicolor, and Malassezia folliculitis. The diagnostic methods used to confirm the presence of Malassezia yeasts include direct microcopy, culture based methods (often a combination of morphological features of the isolate combined with biochemical test), molecular based methods such as Polymerase Chain Reaction techniques, and Matrix Assisted Laser Desorption/Ionization—Time Of Flight mass spectrometry and the chemical imprint method Raman spectroscopy. Skin diseases caused by Malassezia are usually treated with antifungal therapy and if there are associated inflammatory skin mechanisms this is often supplemented by anti-inflammatory therapy. The aim of this paper is to provide an overview of Malassezia related skin disease, diagnostic methods and treatment options.

The Skin and Gut Microbiome and Its Role in Common Dermatologic Conditions

Microorganisms inhabit various areas of the body, including the gut and skin, and are important in maintaining homeostasis. Changes to the normal microflora due to genetic or environmental factors can contribute to the development of various disease states. In this review, we will discuss the relationship between the gut and skin microbiome and various dermatological diseases including acne, psoriasis, rosacea, and atopic dermatitis. In addition, we will discuss the impact of treatment on the microbiome and the role of probiotics.

Malassezia-Can it be Ignored?

Genus Malassezia comprises of 14 species of “yeast like fungi,” 13 of which are lipophilic and 1 is nonlipophilic. They are known commensals and in predisposed individuals they commonly cause a spectrum of chronic recurrent infections. They rarely also cause serious illnesses like catheter-related blood stream infections, CAPD associated peritonitis etc., Though these fungi have been known to man for over 150 years, their fastidious nature and cumbersome culture and speciation techniques have restricted research. Since the last taxonomic revision, seven new species have been added to this genus. Their ability to evade the host immune system and virulence has increased the spectrum of the diseases caused by them. These agents have been implicated as causal agents in common diseases like atopic dermatitis recently. Though culture-based research is difficult, the new molecular analysis techniques and facilities have increased research in this field such that we can devote more attention to this genus to study in detail, their characteristics and their growing implications implications in the clinical scenario.

Comparison between Malassezia Folliculitis and Non-Malassezia Folliculitis

Background

Among the various types of folliculitis, differentiation of Malassezia folliculitis (MF) from other forms of folliculitis is important because it is usually treated with antifungal agents.

Objective

We attempted to find a method to enhance the detection rate of MF, and examined the differences in the clinical manifestation between MF and non-MF (NMF).

Methods

We performed a retrospective study involving patients with folliculitis who were previously diagnosed with MF or NMF on the basis of serial tissue sectioning and diastase-Periodic acid-Schiff (d-PAS) staining findings. The clinical features of MF and NMF were compared.

Results

Among a total of 100 folliculitis patients, 20 were diagnosed with MF and 80 with NMF. Tissues from the 80 patients with NMF were sectioned serially into 10 slices and stained with hematoxylin and eosin stain; among these, 10 had many round-to-oval yeast organisms in the hair follicles that confirmed MF. Finally, d-PAS staining was used to detect the presence of yeast in the NMF slides. Notably, among the 70 d-PAS-stained samples, yeast organisms were found in 6 samples, confirming MF. As a result, the diagnosis of 16 patients changed from NMF to MF. Compared with NMF, MF showed major involvement of the trunk and low involvement of the face and legs as well as male predilection.

Conclusion

Physicians should consider serial sectioning and/or d-PAS staining of folliculitis lesions, particularly of those on the trunk of male patients, even if no yeast organisms are detected initially.

Malassezia folliculitis in an infant

Malassezia folliculitis commonly affects the adolescents and the young adults. We describe an unusual case of Malassezia folliculitis which is particular in age of patient and scare evolution of lesions. The patient was a three-month-old immuno-competent boy. On clinical examination, 1- to 2-mm superficial follicular pustules were observed on his face, neck and upper trunk. Direct microscopy of pustule scrapings and hair follicles showed numerous Malassezia yeast cells. Based on the clinical and mycological data, the diagnosis of Malassezia folliculitis was made. The possible predisposing factors in our patient were heat and sweating, caused by the excessive heat of the summer season in Tunisia. Treatment with topical ketoconazole promoted cure with depressed varioliform scars.