Human infections by Trichophyton mentagrophytes occur mainly due to contact with diseased animals. In Iran, T. mentagrophytes genotype V is the most prevalent variant of the fungus. We aimed to determine the animal reservoir of T. mentagrophytes genotype V infection. The study was done on a total of 577 dermatophyte strains obtained from animals with signs of dermatophytosis and human patients. The list of extensively sampled animals included sheep, cows, cats and dogs. For human cases, epidemiological data were collected. All dermatophyte isolates from animals along with 70 human isolates morphologically similar to T. verrucosum and T. mentagrophytes genotype V were identified by rDNA internal transcribed spacer region restriction fragment length polymorphism analysis and DNA sequencing. A total of 334 animal dermatophyte strains were identified as Microsporum canis, T. mentagrophytes genotype V, T. verrucosum, Nannizzia gypsea, T. mentagrophytes genotype II*, T. mentagrophytes genotype VII, T. quinckeanum, and N. fulva. All clinical isolates identified as T. mentagrophytes genotype V originated from skin and scalp infections. Almost all veterinary isolates of T. mentagrophytes genotype V were cultured from sheep, but epidemiological data on animal-to-human transmission of T. mentagrophytes genotype V infection were limited and we found evidence in favor of interhuman transmission. In Iran, sheep maintain T. mentagrophytes genotype V population and therefore serve as animal reservoir of respective infections. The role of sheep as the source of human dermatophytosis due to T. mentagrophytes genotype V isolates is yet to be proven.In this study, we sampled a variety of animals to determine a reservoir of Trichophyton mentagrophytes genotype V infection. With the use of molecular identification techniques, we show that this infection reservoir is represented by sheep.
Otomycosis is a mycotic infection of the external auditory canal and can be caused by a wide range of fungal species. In this study, we aimed to identify fungal isolates from patients suspected of otomycosis.External ear canal samples were taken from patients referred to the outpatient department of Shahid-Mofatteh Clinic in the city of Yasuj, Iran, and examined by direct microscopy and culture. DNA of the isolated fungi was tested by internal transcribed spacer PCR restriction fragment length polymorphism analysis for identification of yeasts and β-tubulin sequencing for identification of Aspergillus species.Among 275 patients suspected of otomycosis, 144 cases (83 female and 61 male) were confirmed with otomycosis. For 89% (n=128) of positive cultures, microscopy was also positive, while there were no cases with a microscopy-positive and culture-negative result. The predominant predisposing factor was self-cleaning of the external ear using unhygienic tools, and the main risk occupation was 'housewife'. The most common isolated fungi were typically Aspergillus (n=120), including 73 isolates of Aspergillus section Nigri, 43 of section Flavi, 3 of section Terrei and 1 of section Fumigati. After sequencing, 44 out of 73 strains primarily identified as Aspergillus niger turned out to be Aspergillus tubingensis. Thirty-five isolates were identified as Candida, including Candida parapsilosis (n=22), Candida albicans (n=12) and Candida tropicalis (n=1).Aspergillus tubingensis was the most common species involved in otomycosis. This work corroborates the difficulty of precise identification of species within the black Aspergilli by morphological characteristics.
Abstract Background The current study aimed to determine the seroprevalence of Toxoplasma gondii infection among HIV-positive patients and healthy subjects. Methods This study was carried out on HIV-positive patients and healthy individuals in Southwest Iran. Five millilitres of venous blood samples were collected aseptically from each individual. Sera and buffy coats were isolated from each sample and evaluated for anti-Toxoplasma antibodies and T. gondii DNA using ELISA kit and real-time PCR, respectively. Statistical analysis was performed using SPSS 18 software. Results Of 64 AIDS/HIV-positive patients, six (9.3%, 95% CI 7.2 to 11.3%) were seropositive for only IgG and five (7.8%, 95% CI 6.0 to 9.5%) were seropositive for both IgG and IgM. Moreover, among 64 healthy controls, 10 (15.6%, 95% CI 12.1 to 19.0%) were seropositive for only IgG and 2 (3.1%, 95% CI 2.4 to 3.7%) were seropositive for both IgG and IgM. Toxoplasma gondii DNA was detected in six samples (9.3%, 95% CI 7.2 to 11.3%) in the AIDS/HIV-positive patients group and eight samples (5.95%, 95% CI 4.6 to 7.2%) in the control group using real-time PCR. Consumption of undercooked meat was documented as an associated risk factor for T. gondii seropositivity in AIDS patients (OR 4.06, 95% CI 0.966 to 17.09; p=0.045). Conclusions Our findings showed a lower prevalence of Toxoplasma infection in AIDS/HIV-positive patients vs healthy controls; however, a considerable number of AIDS/HIV-positive patients were also seen to be at risk of toxoplasmosis. Based on the findings, screening and prophylaxis for toxoplasmosis should be implemented for all AIDS/HIV-positive patients in Southwest Iran.
Invasive aspergillosis (IA) of the central nervous system (CNS) is a devastating complication which is rarely reported in immunocompromised children. In this case presentation, we reported a rare and fatal IA with spinal cord involvement in a 10-year-old child with X-linked chronic granulomatosis disease (CGD).The child had a previous history of pulmonary tuberculosis. A cervical spine X-ray revealed the involvement of cervical vertebrae (T4/T5) and ribs causing spinal cord compression and epidural abscess. The patient underwent a decompressive laminectomy and mass removal. The histopathology and culture results suggested IA. Despite the aggressive and prolonged therapy, he died within one year. Aspergillus nidulans was identified as the causative agent based on morphological and molecular studies.This synopsis represents the aggressive behavior of infection caused by A. nidulans in the CGD patient.
Dermatophytes are the most common causative agents of superficial mycoses. Species identification of these fungi is important from therapeutic and epidemiological point of wive. Traditional approaches for identification of dermatophytes at the species level, relying on macroscopic and microscopic features of the colonies, usually are time-consuming and unreliable in many circumstances. Recently a broad varieties of rapid and accurate DNA-based techniques were successfuly utilized for species delineation of dermatophytes.The ITS1-5.8S-ITS2 region of rDNA from various reference strains of dermatophyte species were amplified using the universal fungal primers ITS1 and ITS4.The PCR products were digested by a single restriction enzyme, MvaI. The enzyme was evaluated in both in silico and practical PCR-RFLP assay to find the exact differentiating restriction profiles for each species. To validate the standardized PCR-RFLP system, all tested strains were subjected to sequencing and sequence analysis.The obtained RFLP patterns were specific for many species including T. interdigitale, T. rubrum, T. violaceum, M. persicolor, M. audouinii, M. nanum (A. obtusum) and E. floccosum but were similar for some closely related species such as M. canis / M. ferrugineum. Sequencing of the ITS1-5.8S-ITS2 fragment from all type strains affirmed the RFLP findings.It was practically revealed that the ITS-PCR followed by MvaI-RFLP is a useful and reliable schema for identification and differentiation of several pathogenic species and can be used for rapid screening of even closely related species of dermatophytes in clinical and epidemiological settings.