Recent advances on mycotic keratitis caused by dematiaceous hyphomycetes.

Dematiaceous hyphomycetes (DH) are darkly pigmented fungi ubiquitously found all over the world as plant pathogens and saprophytes, and many of the members of this group have emerged as opportunistic pathogens. These fungi are responsible for a wide variety of infections including mycotic keratitis, which is considered as one of the major causes of corneal blindness, particularly in tropical and subtropical countries with an annual global burden of about 1 000 000 patients. The infection is more common in workers working in an outdoor environment. Moreover, trauma is found to be the most important predisposing cause of mycotic keratitis. Considerable delay in diagnosis and scarcity of effective pharmacological drugs are the major factors responsible for increased morbidity and visual impairment. Considering the crucial role of DH in mycotic keratitis, in the present review, we have focused on major DH with special emphasis on their pathogenicity, diagnosis and treatment strategies.

Trends in the molecular epidemiology and population genetics of emerging Sporothrix species.

Sporothrix (Ophiostomatales) comprises species that are pathogenic to humans and other mammals as well as environmental fungi. Developments in molecular phylogeny have changed our perceptions about the epidemiology, host-association, and virulence of Sporothrix. The classical agent of sporotrichosis, Sporothrix schenckii, now comprises several species nested in a clinical clade with S. brasiliensis, S. globosa, and S. luriei. To gain a more precise view of outbreaks dynamics, structure, and origin of genetic variation within and among populations of Sporothrix, we applied three sets of discriminatory AFLP markers (#3 EcoRI-GA/MseI-TT, #5 EcoRI-GA/MseI-AG, and #6 EcoRI-TA/MseI-AA) and mating-type analysis to a large collection of human, animal and environmental isolates spanning the major endemic areas. A total of 451 polymorphic loci were amplified in vitro from 188 samples, and revealed high polymorphism information content (PIC = 0.1765-0.2253), marker index (MI = 0.0001-0.0002), effective multiplex ratio (E = 15.1720-23.5591), resolving power (Rp = 26.1075-40.2795), discriminating power (D = 0.9766-0.9879), expected heterozygosity (H = 0.1957-0.2588), and mean heterozygosity (Havp  = 0.000007-0.000009), demonstrating the effectiveness of AFLP markers to speciate Sporothrix. Analysis using the program structure indicated three genetic clusters matching S. brasiliensis (population 1), S. schenckii (population 2), and S. globosa (population 3), with the presence of patterns of admixture amongst all populations. AMOVA revealed highly structured clusters (PhiPT = 0.458-0.484, P < 0.0001), with roughly equivalent genetic variability within (46-48 %) and between (52-54 %) populations. Heterothallism was the exclusive mating strategy, and the distributions of MAT1-1 or MAT1-2 idiomorphs were not significantly skewed (1:1 ratio) for S. schenckii (χ2 = 2.522; P = 0.1122), supporting random mating. In contrast, skewed distributions were found for S. globosa (χ2 = 9.529; P = 0.0020) with a predominance of MAT1-1 isolates, and regional differences were highlighted for S. brasiliensis with the overwhelming occurrence of MAT1-2 in Rio de Janeiro (χ2 = 14.222; P = 0.0002) and Pernambuco (χ2 = 7.364; P = 0.0067), in comparison to a higher prevalence of MAT1-1 in the Rio Grande do Sul (χ2 = 7.364; P = 0.0067). Epidemiological trends reveal the geographic expansion of cat-transmitted sporotrichosis due to S. brasiliensis via founder effect. These data support Rio de Janeiro as the centre of origin that has led to the spread of this disease to other regions in Brazil. Our ability to reconstruct the source, spread, and evolution of the ongoing outbreaks from molecular data provides high-quality information for decision-making aimed at mitigating the progression of the disease. Other uses include surveillance, rapid diagnosis, case connectivity, and guiding access to appropriate antifungal treatment.

Diagnostic implications of mycetoma derived from Madurella pseudomycetomatis isolates from Mexico.

BACKGROUND: At the dermatology service of the General Hospital of Mexico City, Mexico, two patients, father and son, with black-grain mycetoma were seen. The grains were isolated, and the cultured fungi were identified as Madurella mycetomatis based on morphology. Using the M. mycetomatis specific PCR, amplicons of a different size than that of the M. mycetomatis type strain were obtained. OBJECTIVE: To determine the causative agent of the two black-grain mycetoma cases and develop non-culture-based diagnostic tools to identify them to the species level. METHODS: The M. mycetomatis specific, the internal transcribed spacer (ITS) region, ß-tubulin (BT) and ribosomal binding protein 2 (RBP2) PCRs were used to confirm the identity of the isolates. Genetic variation was established by amplification fragment length polymorphisms. To determine the antifungal susceptibility profile, the Sensititre™ YeastOne™ assay was used. To develop a species-specific PCR primers were designed on the sequenced PCR amplicon from the M. mycetomatis specific PCR. RESULTS: By analyzing the ITS, BT and RBP2 regions the isolates were identified as Madurella pseudomycetomatis. The isolates from father and son were similar but not identical to M. pseudomycetomatis from Venezuela and one from an unknown origin. Madurella pseudomycetomatis isolates were inhibited by itraconazole, posaconazole and voriconazole but showed increased MIC values for amphotericin B and fluconazole. They were not inhibited by the echinocandins and five flucytosine. The two patients were treated with itraconazole resulting in cure for the father while the son was lost to follow-up. The species-specific PCR developed for M. pseudomyceotmatis was discriminative and specific. CONCLUSION: Madurella pseudomycetomatis is genetically diverse with same susceptibility profile as M. mycetomatis and causes eumycetoma in Latin America. The M. pseudomycetomatis specific PCR can be used to identify this causative agent to the species level; however, this needs to be validated in an endemic setting.

Multicenter, International Study of MIC/MEC Distributions for Definition of Epidemiological Cutoff Values for Sporothrix Species Identified by Molecular Methods.

Clinical and Laboratory Standards Institute (CLSI) conditions for testing the susceptibilities of pathogenic Sporothrix species to antifungal agents are based on a collaborative study that evaluated five clinically relevant isolates of Sporothrixschenckii sensu lato and some antifungal agents. With the advent of molecular identification, there are two basic needs: to confirm the suitability of these testing conditions for all agents and Sporothrix species and to establish species-specific epidemiologic cutoff values (ECVs) or breakpoints (BPs) for the species. We collected available CLSI MICs/minimal effective concentrations (MECs) of amphotericin B, five triazoles, terbinafine, flucytosine, and caspofungin for 301 Sporothrix schenckii sensu stricto, 486 S. brasiliensis, 75 S. globosa, and 13 S. mexicana molecularly identified isolates. Data were obtained in 17 independent laboratories (Australia, Europe, India, South Africa, and South and North America) using conidial inoculum suspensions and 48 to 72 h of incubation at 35°C. Sufficient and suitable data (modal MICs within 2-fold concentrations) allowed the proposal of the following ECVs for S. schenckii and S. brasiliensis, respectively: amphotericin B, 4 and 4 µg/ml; itraconazole, 2 and 2 µg/ml; posaconazole, 2 and 2 µg/ml; and voriconazole, 64 and 32 µg/ml. Ketoconazole and terbinafine ECVs for S. brasiliensis were 2 and 0.12 µg/ml, respectively. Insufficient or unsuitable data precluded the calculation of ketoconazole and terbinafine (or any other antifungal agent) ECVs for S. schenckii, as well as ECVs for S. globosa and S. mexicana These ECVs could aid the clinician in identifying potentially resistant isolates (non-wild type) less likely to respond to therapy.

Paraneoplastic Pemphigus. A Life-Threatening Autoimmune Blistering Disease.

Paraneoplastic pemphigus (PNP), a subset of pemphigus, is a unique autoimmune blistering condition that can affect multiple organs other than the skin. It is a life-threatening disease associated with an underlying malignancy, most commonly of lymphoproliferative origin. The clinical picture may resemble pemphigus, pemphigoid, erythema multiforme, graft-versus-host disease, or lichen planus. The earliest and most consistent finding is a painful, severe, chronic and often recalcitrant stomatitis. Treatment of PNP is difficult. Immunosuppressive agents are required to decrease blistering, and treating the underlying tumor may control autoantibody production. In this review, we included essential diagnostic aspects of PNP and the most useful treatment options in the dermatologist practice.

Cutaneous Involvement in the Deep Mycoses: A Literature Review. Part I-Subcutaneous Mycoses. / Afectación cutánea en las micosis profundas: una revisión de la literatura. Parte 1: micosis subcutáneas.

The deep mycoses are uncommon in our setting. These fungal infections occur mainly in immunosuppressed patients or in tropical climates, and include subcutaneous infections and systemic infections. The skin is always involved in the former. In the first part of this review, we describe the main subcutaneous mycoses: sporotrichosis, chromoblastomycosis, mycetoma, phaeohyphomycosis, hyalohyphomycosis, and lacaziosis. Early recognition and treatment is important, as these infections are frequently associated with high morbidity.

Cutaneous involvement in the deep mycoses: A review. Part II -Systemic mycoses. / Afectación cutánea en las micosis profundas: una revisión de la literatura. Parte 2. Micosis sistémicas.

In the second part of this review on the deep mycoses, we describe the main systemic mycoses-paracoccidioidomycosis, coccidioidomycosis, histoplasmosis, mucormycosis, and cryptococcosis-and their cutaneous manifestations. Skin lesions are only occasionally seen in deep systemic mycoses either directly, when the skin is the route of entry for the fungus, or indirectly, when the infection has spread from a deeper focus. These cutaneous signs are often the only clue to the presence of a potentially fatal infection. As with the subcutaneous mycoses, early diagnosis and treatment is important, but in this case, even more so.

Rhinocladiella aquaspersa, proven agent of verrucous skin infection and a novel type of chromoblastomycosis.

We report a case of chromoblastomycosis which resembled sporotrichosis due to the presence of warty nodules and lymphatic distribution on the forearm in a 56-year-old male. Mycological and histopathological investigation of exudates and biopsy tissue samples revealed a granulomatous lesion with muriform cells, the hallmark of chromoblastomycosis. The infection showed only localized expansion with verrucous plaques suggesting a new clinical type of the disease. The causative agent was identified as Rhinocladiella aquaspersa. This case prompted a study of the clinical spectrum of R. aquaspersa, through which we identified a second case caused by this fungus in a 62-year-old Brazilian female. The case was unusual in that R. aquaspersa exhibited hyphae rather than muriform cells in tissue. Given the difficulties treating chromoblastomycosis and other infections caused by melanized fungi, we evaluated the in vitro activities of extended-spectrum triazoles, amphotericin B, and echinocandins against these clinical isolates of R. aquaspersa. Itraconazole (MIC; 0.063 mg/l) and posaconazole (MIC; 0.125 mg/l) had the highest in vitro activities, while voriconazole and isavuconazole had somewhat lower activities (MICs; 2 mg/l) against the isolates. Amphotericin B and anidulafungin each had an MIC of 1 mg/l, whereas the MIC of caspofungin was 8 mg/l.

Sporotrichosis: an update.

Sporotrichosis is the most frequent and worldwide distributed subcutaneous mycoses. The aim of this article is to review the most recent aspects of sporotrichosis about its epidemiology, etiologic agents, mycologic characteristics, clinical features, diagnosis and treatment. The causative agents of sporotrichosis belong to five well defined species of dimorphic fungi of the called Sporothrix schenckii complex. Sporotrichosis and its etiologic agents have specific endemic areas, but it is possible to find epidemics of the disease in practically every continent, the entrance via is cutaneous due to the inoculation of the fungi into the skin after a traumatism and less frequent due to respiratory way. Clinical manifestations are widely variable, with important involvement of the skin and the superficial lymphatic system, but also with affection of the mucosa and some organs like lungs, bones and joints. Nowadays sporotrichosis is considered a true zoonosis with important changes related to the endemic areas and the ecologic features of the causative pathogens. The therapy of choice is the potassium iodide (KI), but other alternatives are itraconazole, terbinafine, thermotherapy and in severe cases amphotericin B. The importance of the recognition of the clinical manifestations of the disease in some non-endemic areas helps to challenge the diagnosis and give an accurate therapy.

Disseminated cutaneous histoplasmosis in acquired immunodeficiency syndrome: report of 23 cases.

Disseminated cutaneous histoplasmosis is an opportunistic infection in patients with acquired immunodeficiency syndrome. We report a series of 23 cases (21 men, two women; median age 29 years) with disseminated cutaneous histoplasmosis seen at two hospital centres. Most of the patients (21/23) were classified as stage C3. The most common dermatological findings were papules, crusting plaques, nodules and ulcers, mainly located on the face and chest. Of the 23 cases, 15 (65%) had pulmonary involvement. Amphotericin B and itraconazole were the main drugs used for treatment. Treatment response was variable: four of the patients were cured, six improved and remain stable, nine patients died, and four patients were lost to follow-up.

Tinea nigra by Hortaea werneckii, a report of 22 cases from Mexico.

Tinea nigra is a superficial mycosis caused by Hortaea werneckii. It is an infrequent asymptomatic infection that affects human palms and soles, and is mostly observed in tropical countries. We evaluate retrospectively twenty-two confirmed cases of tinea nigra from a total of eleven yr (1997-2007) and discuss the epidemiology, clinical features and treatment of this disease. In twelve cases, adults were involved, in 10, children. In nineteen cases the disorder was located on palms of hands and in three on soles of feet. In all cases, the obtained isolates were morphologically identified as Hortaea werneckii and the identification of ten isolates was retrospectively confirmed with the help of sequences of the internal transcribed spacer regions of the ribosomal DNA. The patients received topical treatment with Whitfield ointment, ketoconazole, bifonazole, or terbinafine. Treatment with keratolytic agents and topical antifungals was effective.

Biodiversity of the genus Cladophialophora.

Cladophialophora is a genus of black yeast-like fungi comprising a number of clinically highly significant species in addition to environmental taxa. The genus has previously been characterized by branched chains of ellipsoidal to fusiform conidia. However, this character was shown to have evolved several times independently in the order Chaetothyriales. On the basis of a multigene phylogeny (nucLSU, nucSSU, RPB1), most of the species of Cladophialophora (including its generic type C. carrionii) belong to a monophyletic group comprising two main clades (carrionii- and bantiana-clades). The genus includes species causing chromoblastomycosis and other skin infections, as well as disseminated and cerebral infections, often in immunocompetent individuals. In the present study, multilocus phylogenetic analyses were combined to a morphological study to characterize phenetically similar Cladophialophora strains. Sequences of the ITS region, partial Translation Elongation Factor 1-alpha and beta-Tubulin genes were analysed for a set of 48 strains. Four novel species were discovered, originating from soft drinks, alkylbenzene-polluted soil, and infected patients. Membership of the both carrionii and bantiana clades might be indicative of potential virulence to humans.

Palatal zygomycosis: experience of 21 cases.

OBJECTIVE: To present a clinical report of palatal zygomycosis, its epidemiological, mycological features, and our treatment experience. DESIGN: Retrospective report. SUBJECTS AND METHODS: This is a 25-year long retrospective trial of clinically and mycologically proven cases of zygomycosis. Some patients underwent a biopsy of the palatal lesion and autopsy. This study reports the treatment experience with amphotericin B alone and in combination with itraconazole and fluconazole. RESULTS: Twenty-one cases (18.75%) of zygomycosis with palatal involvement were included in the study, from a total of 112 cases screened. Mean age was 36.5 years, with 18 adults and three children. The associated pre-disposing factors were: ketoacidotic diabetes (five type-1 and 15 type-2), and acute leukaemia in one patient. The clinical varieties were as follows: 19 cases of rhinocerebral (RC) involvement and two disseminated cases. Palatal ulcers occurred in 3/21 early cases (14.3%) and in 16/21 cases after the nasal involvement. All patients received amphotericin B; in four patients, it was combined with itraconazole and four with fluconazole. Clinical and mycological cure was achieved in 4/21 patients (19.04%). CONCLUSION: Zygomycosis with palatal involvement occurs in around 18% of cases, usually associated with RC modalities; it has an acute and generally lethal course.

Otomycosis: clinical and mycological study of 97 cases.

OBJECTIVE: To report otomycosis in a retrospective study and correlate clinical, epidemiological and therapeutic factors. MATERIAL AND METHOD: This study comprises 97 cases of clinically and mycologically proven otomycosis or fungal otitis externa gathered during a 12-year period. RESULTS: Most cases were unilateral (90.7%) and the main predisposing factors associated with the disease were trauma (secondary to the constant scratching) and the use of topical antibiotics. Major causal agents were several species of Aspergillus (63.9%), of which Aspergillus flavus was commonest (26%), followed by Candida albicans (26.8%) and Aspergillus niger (21%). CONCLUSION: The treatment of choice is mainly local toilet of the external auditory canal and the use of systemic antifungal agents to prevent re-infection and the spread of disease.