Tinea Capitis Kerion Type in Three Siblings Caused by Nannizzia Gypsea.

This case report describes a rare occurrence of tinea capitis kerion type caused by Nannizzia gypsea in three siblings. The clinical presentation included pseudo-alopecic plaques with a dirty appearance, erythema, and honey-like crusts. A direct examination revealed ecto-endothrix parasitization in the hair shaft. Shared use of a comb among the siblings was suspected as the mode of transmission. Treatment with oral terbinafine resulted in a complete resolution. Systematic epidemiological surveys on N. gypsea tinea infections are scarce, and preliminary data from our center indicated a higher prevalence. The literature review identified five reported cases of N. gypsea-induced tinea capitis.

Ulcerative Unilateral Tinea Manuum Caused by Nannizzia gypsea.

Dermatophytes, fungi specialized in keratin degradation, are key agents in skin infections, commonly referred to as tineas. Tinea manuum, affecting the hands, typically presents in noninflammatory or inflammatory forms, with ulcerative manifestations rarely reported. Nannizzia gypsea, a relatively uncommon cause of tineas, exhibits variable prevalence influenced by geographic factors. This study investigates a case of Ulcerative Unilateral Tinea Manuum caused by N. gypsea, aiming to explore the differential diagnosis, pathogenesis, and management. A 23-year-old female from the Yucatan Peninsula presented with an ulcerated lesion on her left hand. Initially suspected as Leishmaniasis, subsequent examination revealed tinea manuum. The study discusses differential diagnoses, highlighting the rarity of ulcerative presentations in dermatophytosis, and explores potential pathogenic mechanisms. This case underscores the importance of considering dermatophytes in ulcerative skin lesions and suggests a comprehensive diagnostic approach, particularly in endemic regions.

Molecular identification of isolates of the Trichophyton mentagrophytes complex.

Background: The Trichophyton mentagrophytes complex is the second most common causal agent of dermatophytosis. It comprises five species-T. mentagrophytes, T. interdigitale, T. erinacei, T quinckeanum, and T. benhamie, as well as nine different genotypes of T. mentagrophytes / T. interdigitale-which are morphologically similar; however, their susceptibility to antifungal agents may differ. For targeted therapy and better prognosis, it is important to identify these species at a molecular level. However, since many hospitals lack molecular methods, the actual aetiology of dermatophytosis caused by this complex remains unknown. Objective: To characterize 55 anthropophilic isolates of the T. mentagrophytes complex recovered from a dermatological centre in Yucatán, Mexico. Material and methods: Fifty-five isolates of the T. mentagrophytes complex were obtained from patients with tinea capitis, tinea pedis, tinea corporis, tinea barbae, and tinea unguium. They were characterized by their colonial and microscopic morphology on Sabouraud dextrose agar (SDA) and through the sequencing of a fragment from the region ITS1-5.8S-ITS2. Results: All colonies grown on SDA were white. Forty-six isolates formed colonies with a powdery texture, while nine isolates formed colonies with a velvety texture. The micromorphological features were typical of the T. mentagrophytes complex. The molecular analysis revealed that 55 isolates were microorganisms that belonged to the T. mentagrophytes complex, that 46 formed powdery colonies representing T. mentagrophytes, and that the other nine isolates that formed velvety colonies represented T. interdigitale. The latter nine isolates were obtained from patients with tinea pedis, tinea corporis, and tinea unguium. Conclusions: The colony morphology on SDA led to the identification of 46 isolates as T. mentagrophytes and nine isolates as T. interdigitale. At a molecular level, the species identified by their morphology were identified only as T. mentagrophytes complex.

Identification of Mycobacterium leprae and Mycobacterium lepromatosis in Formalin-Fixed and Paraffin-Embedded Skin Samples from Mexico.

BACKGROUND: The causative agents of leprosy are the well-known Mycobacterium leprae and the newly discovered Mycobacterium lepromatosis. This agent was found in 2008, and it was found to be the cause of diffuse lepromatous leprosy in two Mexican patients. OBJECTIVE: The objective of this work was to determine if M. leprae and M. lepromatosis were present in formalin-fixed and paraffin-embedded skin samples from cases from different regions in Mexico. METHODS: A total of 41 skin samples were obtained from 11 states of Mexico. All patients' samples were diagnosed by clinical and histopathological analyses. Total DNA was isolated using a Qiagen-DNeasy blood and tissue kit and molecular identification was achieved by two semi-nested polymerase chain reactions. RESULTS: The 41 patient included 33 samples from men and 8 samples from women; 29 samples were polymerase chain reaction (PCR)-positive to Mycobacterium and 12 samples were PCR-negative. From those 29 samples, 13 were PCR-positive to M. leprae, 8 to M. lepromatosis and 8 were positive to both species. The histopathological diagnosis included; Nodular lepromatous leprosy (NLL); Diffuse lepromatous leprosy (DLL); and Borderline leprosy (BL). The 29 PCR-positive samples were classified as follow: 14 NLL, 4 DLL, and 11 BL. In the 12 samples negative to Mycobacterium, 7 showed the NLL, 2 DLL and 3 BL. CONCLUSION: These findings add evidence to the M. leprae and M. lepromatous distribution, clinical forms and participation of dual infections in Mexico.