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1 Department of Mycology, Hospital General de México, Sánchez
Azcona 317-202, Col del Valle, México D.F. CP 03020, Mexico
2 Dermatology Service, Hospital General de México, Sánchez
Azcona 317-202, Col del Valle, México D.F. CP 03020, Mexico
3 CBS Fungal Biodiversity Centre, P.O. Box 85167, NL-3508 AD Utrecht, The
Netherlands
4 Institute of Biodiversity and Ecosystem Dynamics, University of Amsterdam,
Amsterdam, The Netherlands
5 Department of Medical Mycology and Parasitology, School of Medicine,
Mazandaran University of Medical Sciences, Sari, Iran
*
Correspondence: Alexandro Bonifaz,
a_bonifaz{at}yahoo.com.mx.
| Abstract |
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Keywords Hortaea werneckii / keratolysis / melanized fungi / superficial mycosis / tinea nigra / tinea palmaris
| INTRODUCTION |
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et al.
2008). The present article is a retrospective report of cases of
tinea nigra, its epidemiological, clinical, and therapeutic features, as well
as a review of the disorder. | MATERIAL AND METHODS |
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After diagnosis, the patients received Whitfield ointment topical treatment (salicylic acid 3 %, benzoic acid 2 %) twice daily for 15 ds, or one of the following antifungals as creams: ketoconazole 2 % (Nizoral), bifonazole 1 % (Mycospor) and terbinafine 1 % (Lamisil). Subsequently, follow-up of patients was performed for 1–2 mos after application of the last dose. Cure was defined as the absence of clinical signs and negative culturing (Table 2).
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| RESULTS |
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Direct examinations were positive in 21/22 cases (95.4 %; Figs 2F–H). All patients had a positive culture that was preliminarily identified as Hortaea werneckii; active growth was evident on average after 5.5 ds (Figs 2, 3, 4). Biopsies were taken in two patients (due to confusion with nevi); however, perivascular infiltrates were reported in both cases and short fungal filaments could be found on the stratum corneum.
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| DISCUSSION |
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2006,
Kogej et al.
2007). The melanized, polymorphic and yeast-like fungus Hortaea werneckii may be difficult to recognize by morphological characters. Its relatively restricted, black primary cultures, 1 µm wide annellated zones and one-septate conidia facilitate its specific identification. ITS sequences show limited variation, and the species is clearly distinct from other, closely related taxa (Zalar et al. 1999). No teleomorph of this fungus has been found. It is known to be phylogenetically affiliated to the order Capnodiales (Crous et al. 2007a).
In some regions of Venezuela, Stenella araguata Syd. has been reported as a causative agent of tinea nigra (Perez et al. 2005). This species is known from only two occasions: the original specimen caused leaf spots on vegetation (Pithecellobium lanceolatum, Mimosaceae) and its taxonomic status is now unclear. Another isolate came from a case of tinea nigra (Crous et al. 2007b). The ITS of the latter, CBS 105.75, was sequenced (EU019250 [GenBank] ) and mentioned twice under invalid name "Catenulostroma castellanii" (Crous et al. 2007a,b). Based on ITS rDNA data, the strain CBS 105.75 is clearly different from H. werneckii (G.S. de Hoog, unpublished data), but judging from rDNA large subunit data (Crous et al. 2007a) the species is a close relative and might represent a second agent of tinea nigra. As long as its identity with the type of S. araguata is pending, it is difficult to attribute a taxonomic name to this fungus.
Tinea nigra is an uncommon discolouration of the skin. Most reports originate from tropical, humid climate zones. Cases from Latin America have been reported from Panama, Colombia, Venezuela, Brazil and Mexico (Chang & Arenas 1983, Durán et al. 1983, Severo et al. 1994, Pegas et al. 2003, Perez et al. 2005), while Asian reports came from India, Sri Lanka, Myanmar and Polynesia (Uezato et al. 2006). The disorder is rare in Europe (Hughes et al. 1993, Reid 1998) and the United States (Burke 1993, Shanon et al. 1999, Tseng et al. 1999). Predisposing factors associated with the condition are hyperhydrosis (Severo et al. 1994, Bonifaz 2001, Padilla et al. 2002) and presence in coastal see areas or hypersaline environments, where the causative agent may be picked up from the natural habitat (de Hoog & Gerrits van den Ende 1992).
Our 22 cases present a large series and, unlike other published reports (for example, Severo et al. 1994, Perez et al. 2005), cover a long follow-up period. Our cases are clinically and demographically similar to the ones reported from other continents (Uezato et al. 2006). Tinea nigra is considered a rare disease. According to statistics in our hospital in Mexico City, D.F., it accounts for 0.085 % of all mycoses. The frequency of the disorder may be higher, but due to its asymptomatic nature and the possibility of spontaneous cure, patients seldom reach the doctor's office. This is the case only when patients worry because of confusion with other pigmented skin diseases, such as melanoma.
The disorder has no preference for age categories (Table 1), cases equally occurring in adults and children, and no gender differences are observed (Durán et al. 1993, Pegas et al. 2003). Course of the infection according to our data was 1–18 mos, with a mean incubation time of 3.8 mos. According to the patient's information, we think that the developing lesions become visible within 15–30 ds. The lesions are invariably flat, not elevated and without inflamed margins; they consist of pigmented, mostly brownish, irregular and asymptomatic macules and with well-defined borders, and are covered by fine scaling. Some patients report that throughout the day a change in colour of the macules can be observed: early in the morning macules can appear in more intense pigmentations but they fade as the day goes by. This is probably due to the fact that the fungus is cleared from the hands as a result of daily activities. Only one patient in our study, presented with erythema, also reported moderate itching as was noted in other studies (Hughes et al. 1993, Perez et al. 2005).
Tinea nigra has a major clinical relevance because it can be mistaken for various types of nevi. In some reports it even was misidentified as melanomas. Also some of our cases, seen at external dermatology services, were initially diagnosed as various types of nevi (Hall & Perry 1998, Tseng et al. 1999). With this incorrect diagnosis, two of the cases underwent biopsies, which lead to the observation of fungal elements in the stratum corneum with a discrete perivascular infiltrate. Differential diagnosis is essential, due to the extremely different prognosis of the various conditions. The tinea nigra macule denotes the superficial growth of the fungus, strictly limited to the stratum corneum. This may be revealed by dermatoscopy, which is a technique allowing the observation of fungal elements with certainty, particularly when flanked with microbiological tests (Smith et al. 2001; Fig. 2F).
The palms of hands constitute the major location of the disease, which explains the often-used name "tinea nigra palmaris". Most cases are unilateral but also bilateral infections can be observed (Tseng et al. 1999), probably resulting from autoinoculation (Fig. 2A). In our study, in 19/22 cases the disorders were located on the palms and 3 on the soles. Surprisingly, one of the sole infections was located in the interdigital spaces (Fig. 2E) and had a discrete pigmentation (case 13, strain CBS 123045; see Table 1), which led to suspect dermatosis neglecta caused by the chronic deposition of dirt or filth (Ruiz-Maldonado et al. 1999). We are unaware of any case of a tinea nigra located in the interdigital spaces. Recently a similar condition caused by chaetothyrialean black yeast-like fungi was reported (Badali et al. 2008), differing by the fact that the etiologic fungus concerned, Cladophialophora saturnica showed invasive behaviour, while Hortaea werneckii is strictly commensal. The two cases located on the plantar region were also informative, as they concerned patients with the habit of running barefoot along the seaside, an environment with high salinity and probably the natural niche of the fungus. Both cases had a clinical history of hyperhydrosis probably resulting in saline plantar cutaneous conditions and adhesion of the fungus (Fig. 2C; Göttlich et al. 1995). It is important to comment on case 16 (Table 1), an irregular worker in saltpans, that is considered the natural enviroment of H. werneckii. It is probable that more saltpan-workers carry the disorder but due to the asymptomatic nature of the disease do not seek medical help (Gunde-Cimerman et al. 2000).
Recently Ng et al. (2005) reported the isolation of H. werneckii from the serum and a splenic abscess of a human patient. This is an exceptional case, in which the fungus behaved as an opportunistic pathogen and was the causative agent of a systemic phaeohyphomycosis.
Given the taxonomic uncertainties mentioned above, confirmation of identification with microbiological and molecular tests is compulsory. Direct KOH examinations provide us with quick information and demonstrate the short, tortuous, thick, light brown hyphae, which may occasionally be darkened, and sometimes present short filaments and yeast-like cells. The pigmentation of hyphae unambiguously distinguishes tinea nigra from various other types of dermatophytoses or skin infections (Hughes et al. 1993, Gupta et al. 2003). The use of chlorazol black (Feuilhade de Chauvin 2005) as a clearing solution is not recommended because this reagent stains fungal elements black, which interferes with distinction from dermatophyte hyphae. In our study nearly all cases were diagnosed by direct examination and were confirmed by culture. Colonies of Hortaea werneckii grow on a standard media within 5–8 ds. They are initially black with a creamy appearance and later become filamentous. This morphological transition is characteristic for H. werneckii, but is also known in Exophiala (Chaetothyriales). Filamentous isolates may be mistaken for some chaetothyrialean fungi or for Cladosporium spp. Conidia appear as pigmented yeast cells with a dark central septum, the outer wall later becoming thick-walled, heavily pigmented. Conidia finally germinate with hyphae resulting in yeast-like colonies that gradually change over into filaments to complete the anamorph life cycle.
Molecular diagnostics of H. werneckii were developed by Uijthof et al. (1994) using PCR-fingerprinting techniques and by Zalar et al. (1999) using sequencing of rDNA ITS. Uezato et al. (1989) applied molecular diagnostics in clinical practice. Abliz et al. (2003) developed specific primers on the basis of ITS data and validated the primers by a comparison with 42 other melanized fungal species, including chaetothyrialean agents of cutaneous and subcutaneous disease.
The treatment of tinea nigra is very simple and effective. Most cases resolve with only keratinolytic agents like urea, salicylic acid and Whitfield ointment, applied once or twice a day (Sayegh-Carreno et al. 1989, Bonifaz 2001). Most of the cases in our report were managed with Whitfield ointment. Mean treatment duration (Table 2) was approximately 15 ds; two cases presented spontaneous cure. Most topical antifungals are also effective. Good treatment results have been reported using miconazole (Marks et al. 1980), ketoconazole (Chang & Arenas 1983, Burke 1993), bifonazole (Meisel 1984), terbinafine (Shanon et al. 1999) and ciclopirox olamine (Rossen & Lingappan. 2006). There is even a report of oral itraconazole therapy (Gupta et al. 1997), which is not recommended for this commensal fungus. Most cases in our study resolved with topical therapy within two weeks.
| References |
|---|
|
|
|---|
Abliz P, Fukushima K, Takizawa K, Miyaji M, Nishimura K (2003). Specific oligonucleotide primers for identification of Hortaea werneckii, a causative agent of tinea nigra. Diagnostic Microbiology and Infectious Diseases 46:89 –93.[CrossRef][Medline]
Anomymous (2004). Guidelines. Classification of organisms – Fungi. Swiss Agency for the Environment, Forests and Landscape.
Badali H, Carvalho VO, Vicente V, Attili-Angelis D, Kwiatkowski IB, Gerrits van den Ende AHG, Hoog GS de (2008). Cladophialophora saturnica sp. nov., a new opportunistic species of Chaetothyriales revealed using molecular data. Medical Mycology 7:1 –12.
Bonifaz A (2001). Tinea nigra. In Arenas R, Estrada R (eds): Handbook of Tropical Dermatology. Landes Bioscience eds. Georgetown, Texas:24 –26.
Burke WA (1993). Tinea nigra: treatment with topical ketoconazole. Cutis 52:209 –211.[Medline]
Chang P, Arenas R (1983). Tiña negra palmar tratada con ketoconazol. Dermatología Revista Mexicana 27:218 –219.
Crous PW, Braun U, Groenewald JZ (2007a).
Mycosphaerella is polyphyletic. Studies in
Mycology 58:1
–32.
Crous PW, Braun U, Schubert K, Groenewald JZ (2007b).
Delimiting Cladosporium from morphologically similar genera.
Studies in Mycology 58:33
–56.
Durán C, Carbajosa J, Arenas R (1983). Tiña negra plantar. Estudio de tres casos en México. (1993). Dermatología Revista Mexicana 36:170 –171.
Feuilhade de Chauvin M (2005). New diagnostic techniques. Journal of European Academy Dermatology and Venereology 19, Suppl. 1: 20–24.[CrossRef]
Göttlich E, Hoog GS de, Yoshida S, Takeo K, Nishimura K, Miyaji M (1995). Cell surface hydrophobicity and lipolysis as essential factors in human tinea nigra. Mycoses 38:489 –494.[Medline]
Gunde-Cimerman N, Zalar P, Hoog GS de, Plemenitas A (2000). Hypersaline waters in salterns: natural ecological niches for halophilic black yeasts. FEMS Microbiological Ecology 32:235 –240.
Gupta AK, Chaudhry M, Elewski B (2003). Tinea corporis, tinea cruris, tinea nigra, and piedra. Dermatologia Clinica 21:395 –400.[CrossRef]
Gupta G, Burden AD, Shankland GS, Fallowfield ME, Richardson MD (1997). Tinea nigra secondary to Exophiala werneckii responding to itraconazole. British Journal of Dermatology 137:483 –484.[CrossRef][Medline]
Hall J, Perry VE (1998). Tinea nigra palmaris: differentiation from malignant melanoma or junctional nevi. Cutis 62:45 –46.[Medline]
Hoog GS de, Gerrits van den Ende AHG (1992). Nutritional pattern and eco-physiology of Hortaea werneckii, agent of human tinea nigra. Antonie van Leeuwenhoek 62:321 –329.[CrossRef][Medline]
Hoog GS de, Guarro J, Gené J, Figueras MJ (2000). Atlas of Clinical Fungi, 2nd ed. Centraalbureau voor Schimmelcultures / Universitat Rovira i Virgili, Utrecht / Reus.
Hughes JR, Moore MK, Pembroke AC (1993). Tinea nigra palmaris. Clinical and Experimental Dermatology 18:481 –483.[CrossRef][Medline]
Kogej T, Stein M, Volkmann M, Gorbushina AA, Galinski EA,
Gunde-Cimerman N (2007). Osmotic adaptation of the halophilic
fungus Hortaea werneckii: role of osmolytes and melanization.
Microbiology 153:4261
–4273.
Marks JG, King RD, Davis BM (1980). Treatment of tinea
nigra palmaris with miconazole topically. Archives of
Dermatology 116:321
–322.
McGinnis MR, Schell WA, Carson J (1985). Phaeoannellomyces and the Phaeococcomycetaceae, new dematiaceous blastomycete taxa. Sabouraudia 23:179 –188.[Web of Science][Medline]
Meisel C (1984). Treatment of tinea palmaris with Mycospor. Dermatologica 169, Suppl. 1:121 -123.[Medline]
Ng KP, Soo-Hoo TS, Na SL, Tay ST, Hamimah H, Lim PC, Chong PP, Chavez AJ, Messer SA (2005). The mycological and molecular study of Hortaea werneckii isolated from blood and splenic abscess. Mycopathologia 159:495 –500.[CrossRef][Medline]
Padilla MC, Medina CD, Eng A, Alonzo L (2002). Tiña negra. Presentación de un caso. Revista Centro Dermatológico Pascua 11:139 –141.
Pegas JR, Criado PR, Lucena SK, de Oliveira MA (2003). Tinea nigra: report of two cases in infants. Pediatrics Dermatology 20:315 –317.[CrossRef]
Perez C, Colella MT, Olaizola C, Hartung de Capriles C, Magaldi S, Mata-Essayag S (2005). Tinea nigra: report of twelve cases in Venezuela. Mycopathologia 160:235 –238.[CrossRef][Medline]
Petrovic U (2006). Role of oxidative stress in the extremely salt-tolerant yeast Hortaea werneckii. FEMS Yeast Research 6:16 –22.
Plemenita
A, Vaupoti
T, Lenassi M, Kogej T,
Gunde-Cimerman N (2008). Adaptation of extremely halotolerant
black yeast Hortaea werneckii to increased osmolarity: a molecular
perspective at a glance. Studies in Mycology
61: 67-75.
Reid BJ (1998). Exophiala werneckii causing tinea nigra in Scotland. British Journal of Dermatology 139:157 –158.[Medline]
Rosen T, Lingappan A (2006). Rapid treatment of tinea nigra palmaris with cilopirox olamine gel, 0.77 %. Skinmed 5:201 –203.[CrossRef][Medline]
Ruiz-Maldonado R, Duran-McKinster C, Tamayo-Sanchez L,
Orozco-Covarrubias ML (1999). Dermatosis neglecta: dirt crusts
simulating verrucous nevi. Archives of Dermatology
135:728
–729.
Sayegh-Carreno R, Abramovits-Ackerman W, Giron GP (1989). Therapy of tinea nigra plantaris. International Journal of Dermatology 28:46 –48.[CrossRef][Medline]
Severo LC, Bassanesi MC, Londero AT (1994). Tinea nigra: report of four cases observed in Rio Grande do Sul (Brazil) and a review of Brazilian literature. Mycopathologia 126:157 –162.[CrossRef][Medline]
Shannon PL, Ramos-Caro FA, Cosgrove BF, Flowers FP (1999). Treatment of tinea nigra with terbinafine. Cutis 64:199 –201.[Medline]
Smith SB, Beals SL, Elston DM, Meffert JJ (2001). Dermoscopy in the diagnosis of tinea nigra plantaris. Cutis 68:377 –380.[Medline]
Tseng SS, Whittier S, Miller SR, Zalar GL (1999). Bilateral tinea nigra plantaris and tinea nigra plantaris mimicking melanoma. Cutis 64:265 –268.[Medline]
Uezato H, Gushi M, Hagiwara K, Kayo S, Hosokawa A, Nonaka S (1989). A case of tinea nigra palmaris in Okinawa, Japan. Journal of Dermatology 33:23 –29.
Uijthof JM, Cock AW de, Hoog GS de, Quint WG, Belkum A van (1994). Polymerase chain reaction-mediated genotyping of Hortaea werneckii, causative agent of tinea nigra. Mycoses 37:307 –312.[Medline]
Zalar P, Hoog GS de, Gunde-Cimerman N (1999). Ecology
of halotolerant dothideaceous black yeasts. Studies in
Mycology 43:38
–48.
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