Epidemiological characteristics of Malassezia folliculitis and use of the May-Grünwald-Giemsa stain to diagnose the infection ☆ Murat Durdu a , Mümtaz Güran b , Macit Ilkit b, ⁎ a Department of Dermatology, Faculty of Medicine, Başkent University Adana Hospital, Adana, Turkey b Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana 01330, Turkey abstract article info Article history: Received 27 February 2013 Received in revised form 27 March 2013 Accepted 2 April 2013 Available online xxxx Keywords: Acne vulgaris Cytology Itraconazole Pityriasis versicolor rDNA Wood’s light Various bacterial, fungal, parasitic, and viral pathogens can cause folliculitis, which is often mistakenly treated with antibiotics for months or even years. A laboratory diagnosis is required before therapy can be planned. Here, we describe the prevalence and risk factors, as well as the clinical, cytological, and mycological characteristics, of patients with Malassezia folliculitis (MF) in Adana, Turkey. We also report the treatment responses of the MF patients and describe the Malassezia spp. using culture-based molecular methods. Cytological examinations were performed in 264 folliculitis patients, 49 of whom (18.5%) were diagnosed with MF. The positivity of the May-Grünwald-Giemsa (MGG) smear was higher (100%) than that of the potassium hydroxide test (81.6%). Using Wood's light, yellow-green fluorescence was observed in 66.7% of the MF patients. Identification using the rDNA internal transcribed spacer region revealed that Malassezia globosa was the most common species, followed by Malassezia sympodialis, Malassezia restricta, and Malassezia furfur. The MF patients were treated with itraconazole capsules (200 mg/d) for 2 weeks. Complete recovery was observed in 79.6% of the patients. These novel findings help improve our current understanding of the epidemiological characteristics of MF and establish MGG as a practical tool for the diagnosis of MF. © 2013 Elsevier Inc. All rights reserved. 1. Introduction Lipophilic yeasts of the genus Malassezia are common skin commensals. However, they may cause infections in the presence of predisposing factors, such as environmental changes and/or alter- ations in the host's defense mechanisms (Batra et al., 2005; Gupta et al., 2004a). In current taxonomy, 14 Malassezia spp. have been identified, with 9 described in humans (i.e., Malassezia furfur, Malassezia sympodialis, Malassezia globosa, Malassezia obtusa, Malassezia slooffiae, Malassezia restricta, Malassezia dermatis, Malassezia japonica, and Malassezia yamatoensis) and 5 in animals (Malassezia pachydermatis, Malassezia caprae, Malassezia equina, Malassezia nana, and Malassezia cuniculi)(Batra et al., 2005; Cabaňes et al., 2011; Gupta et al., 2004a). Malassezia spp. are associated with various dermatological diseases, such as pityriasis versicolor (PV); seborrheic dermatitis (SD); atopic dermatitis (AD); Malassezia folliculitis (MF); dandruff; psoriasis; and, rarely, onychomycosis (Batra et al., 2005; Gupta et al., 2004a). Culture-dependent (1996–2002) and culture-independent (2003– present) methods have been used to identify Malassezia spp. (Guého et al., 1996; Makimura et al., 2000; Sugita et al., 2003). Questionable results have been obtained using conventional identification tech- niques because of the continual increase in novel species (Batra et al., 2005; Guého et al., 1996). Gaitanis et al. (2009a) discussed the pros and cons of each molecular typing method and highlighted the potential scarcity of epidemiological data. Briefly, these methods involve targeting the polymerase chain reaction (PCR) amplification of selected sequences and subsequently searching for mutations (Gaitanis et al., 2006; Sugita et al., 2003; Tajima et al., 2008), random PCR amplifications of polymorphic DNA, or minisatellites within the genome (Gaitanis et al., 2009b; Gupta et al., 2004b; Makimura et al., 2000). In 1 study, an analysis of cutaneous Malassezia microbiota in 770 healthy Japanese individuals using real-time PCR revealed that M. globosa and M. restricta together accounted for more than 70% of the Malassezia spp. (Sugita et al., 2010). Consistent with this finding, studies including molecular analysis data have reported that M. globosa is mainly responsible for PV, whereas AD, SD, and MF are principally caused by M. globosa and M. restricta (Akaza et al., 2009; Sugita et al., 2006; Tajima et al., 2008). Although MF is the most common type of fungal folliculitis, little is known about its epidemiological characteristics. Clinically, MF is Diagnostic Microbiology and Infectious Disease xxx (2013) xxx–xxx ☆ Conflict of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and the writing of the paper. ⁎ Corresponding author. Tel.: +90-532-286-0099; fax: +90-322-457-3072. E-mail address: milkit@cu.edu.tr (M. Ilkit). 0732-8893/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.diagmicrobio.2013.04.011 Contents lists available at SciVerse ScienceDirect Diagnostic Microbiology and Infectious Disease journal homepage: www.elsevier.com/locate/diagmicrobio Please cite this article as: Durdu M, et al, Epidemiological characteristics of Malassezia folliculitis and use of the May-Grünwald-Giemsa stain to diagnose the infection..., Diagn Microbiol Infect Dis (2013), http://dx.doi.org/10.1016/j.diagmicrobio.2013.04.011