CÁC CHỦNG VI NẤM NGOÀI DA PHÂN LẬP ĐƯỢC VÀ ĐỘ NHẠY CẢM VỚI CÁC THUỐC KHÁNG NẤM HIỆN NAY TRÊN BỆNH NHÂN ĐẾN KHÁM TẠI BỆNH VIỆN DA LIỄU THÀNH PHỐ HỒ CHÍ MINH NĂM 2021

Đặt vấn đề: Nhiễm vi nấm ngoài da (dermatophytosis) là một trong những bệnh phổ biến và khó điều trị. Vấn đề chẩn đoán tác nhân gây bệnh chưa được quan tâm triệt để, cộng với tình trạng kháng thuốc ngày càng tăng. Do đó cần thiết phải có nghiên cứu khảo sát các chủng vi nấm ngoài da hiện đang lưu hành trên các bệnh nhân đến khám tại bệnh viện Da Liễu, từ đó có cơ sở chẩn đoán và điều trị hiệu quả. Mục tiêu: Phân lập, định danh và tìm hiểu tỷ lệ của các chủng vi nấm ngoài da. Khảo sát độ nhạy cảm với các thuốc khám nấm hiện nay trên các bệnh nhân đến khám tại bệnh viện Da Liễu Thành phố Hồ Chí Minh. Phương pháp nghiên cứu: cắt ngang mô tả, đối tượng từ 339 mẫu bệnh phẩm da, tóc, móng nghi ngờ do vi nấm ngoài da đến khám ngoại trú tại Khoa Khám bệnh Bệnh viện Da Liễu Thành phố Hồ Chí Minh từ tháng 1 đến tháng 5 năm 2021 có chỉ định soi tươi tìm vi nấm của bác sĩ lâm sàng. Các bệnh phẩm được cấy vào môi trường Dermatophyte test medium (DTM) và Sabouraud dextrose Agar (SDA) để phân biệt và định danh. Các chủng vi nấm ngoài da được thực hiện kháng nấm bằng phương pháp đĩa khuếch tán để đánh giá hiệu lực gồm các chất kháng nấm: fluconazole, griseofulvin, itraconazole, ketoconazole. Kết quả: Tỷ lệ bệnh nhân được chẩn đoán nhiễm nấm ngoài da là 47,2%. Trên 107 mẫu bệnh phẩm nuôi cấy phân lập được vi nấm ngoài da, Trichophyton rubrum chiếm tỉ lệ cao nhất là 63,55%, kế đến là Trichophyton mentagrophytes với tỉ lệ 28,04%, Microsporum gypseum chiếm tỉ lệ 4,67%, và cuối cùng là Microsporum canis có tỉ lệ thấp nhất là 3,74%. Tất cả vi nấm ngoài da đều nhạy với thuốc kháng nấm itraconazole (100%); trong khi đó, mức độ nhạy cảm với griseofulvin là 98%. Đối với thuốc kháng nấm ketoconazole, mức độ nhạy với thuốc đạt 52,9%, và có 30,4% mẫu vi nấm ngoài da kháng với ketoconazole. Kết luận: Tỉ lệ nhiễm nấm da do vi nấm ngoài da của bệnh nhân còn cao; trong đó, loài Trichophyton rubrum là loài thường gặp nhất. Kết quả kháng nấm đồ cho thấy tình trạng đề kháng ngày càng tăng của vi nấm, có thể giảm hiệu quả điều trị.

Identification and antimicrobial susceptibility of microbial agents of otitis externa in dogs

In this study, a total of 277 unmedicated dogs with otitis externa were used. Overall, 413 agents were isolated from 277 ear swab samples; 52.7% of the cases were mono-infections (146 cases), and 37.1% of the cases were poly-infections (103 cases). In 10.1% (28) of the cases, neither bacteria nor yeasts were isolated. Coagulase-positive Staphylococcus spp. were the most frequently isolated bacteria and were found in 90 (21.8%) of the samples. Fifty-eight samples, (14%) were positive for Staphylococcus aureus, 51 (12.3%) for Pseudomonas aeruginosa, 27 (6.5%) for Proteus mirabilis, 27 (6.5%) for Malassezia pachydermatis, 21 (5%) for Corynebacterium spp., 21 (5%) for β-haemolytic Streptococcus spp., 15 (3.6%) for Staphylococcus pseudointermedius, 12 (2.9%) for Proteus spp., 12 (2.9%) for Escherichia coli, 9 (2.1%) for Acinetobacter calcoaceticus, 7 (1.6%) for Trichophyton mentagrophytes, 5 (1.2%) for Staphylococcus auricularis, and 46 (11.1%) for different bacteria and yeasts. A total of 14 different bacteria and yeasts were isolated and identified. Kirby-Bauer antibiotic susceptibility testing was carried out for 10 different antibiotics. The bacterial isolates were found to be resistant to amoxicillin-clavulanic acid (45%), gentamycin (28%), ampicillin/cloxacillin (69%), tobramycin (28%), amikacin (23%), enrofloxacin (47%), chloramphenicol (58%), doxycycline (65%), lincomycin/spectinomycin (58%) and polymyxin B (62%). In conclusion, it is important to test the antimicrobial sensitivity of aetiological agents of otitis externa before treatment so as to prevent the development of antibiotic resistance in bacteria and yeasts.

Synthesis and biological evaluation of pyrazole analogues linked with 1,2,3-triazole and 4-thiazolidinone as antimicrobial agents

A new series of 2-[3-(5-methyl-1-phenyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-4-pyrazolyl]-3-aryl-1,3-thiazolan-4-one 5(a-i) have been designed, synthesized and evaluated for their in vitro antibacterial activity against Gram positive bacteria viz. Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 6538p), Micrococcus luteus (IFC 12708) and Gram negative bacteria viz. Proteus vulgaris (ATCC 3851), Salmonella typhimurium (ATCC 14028), Escherichia coli (ATCC 25922) the antifungal activity against Candida albicans (ATCC 10231), Aspergillus fumigatus (HIC 6094), Trichophyton rubrum (IFO 9185), Trichophyton mentagrophytes (IFO 40996). Antibacterial evaluation indicates that compounds containing 4-methoxyphenyl 5c, 4-fluorophenyl 5d and 2,5-difluorophenyl 5h groups on thiazolidinone ring showed significant activity equal to that of standard drug. The antifungal evaluation shows that compound 5c is highly active against A. fumigatus, compound 5d and 5h were also active against C. albicans and A. fumigatus.

Clinico-Mycological Profile of Dermatophytosis in a Tertiary Care Hospital of Eastern Nepal

Background: Dermatophytes are keratinophilic and keratinolytic fungi which are responsible for dermatophytosis. There are three genera of dermatophytes; Trichophyton, Microsporum and Epidermophyton. As they have affinity to keratin rich tissue, they produce dermal inflammatory response, intense itching and cosmetically poor appearance. The varied clinical presentation of tinea results in delay in diagnosis, poor compliance in follow up of cases, and consequently spread of infection in the community has rekindled interest in rapid identification of species. Materials and Methods: A hospital based cross sectional study was carried out in the department of Microbiology, Nobel medical college from January 2019 to December 2019. Clinically suspected 200 cases of dermatophytosis attending Out Patient Department were studied. Isolation and identification was done by various tests like macroscopic, microscopic and biochemical tests. Results: Out of 200 specimens, 138 (69%) were skin scraping, 42 (21%) were nail clipping and 20 (10%) were hair stubs. Highest incidence was seen in the age group 21-40 years with 115 (57.5%) cases followed by 41-60 years 46 (23%) cases. In our study male preponderance of 158 (79%) and female of 42 (21%) were seen. Tinea corporis was found to be the commonest clinical type with 96 (48%) cases followed by tinea unguinum, 42 (21%), Tinea cruris 10 (11.36%), Tinea capitis 5 (5.68%), Tinea faciei 4 (4.54%), Tinea pedis 2 (2.27%). Among the fungal isolates Trichophyton rubrum (67.04%) was the most common etiological agent followed by Trichophyton mentagrophytes (13.63%), Epidermophyton 10 (11.36%), Trichophyton violaceum 4 (4.54%) and Epidermophyton floccosum 3 (3.4%). Conclusion: The most common clinical presentation was tinea corporis followed by tinea unguinum. T. rubrum was the most common etiological agent of dermatophytosis

AKTIVITAS ANTIFUNGI DARI EKSTRAK (Mikania micrantha Kunth) TERHADAP Trichophyton mentagrophytes dan Trichophyton rubrum

Abstrak Penyakit kulit yang disebabkan oleh jamur masih sering terjadi dibeberapa kalangan masyarakat. Beberapa tumbuhan mempunyai aktivitas sebagai antifungi masih digunakan oleh masyarakat salah satunya sembung rambat (Mikania micrantha Kunth). Penelitian ini bertujuan untuk mengetahui aktivitas antijamur ekstrak Mikania micrantha Kunth terhadap Trichophyton mentagrophytes dan Trichophyton rubrum. Daun Mikania diekstrak dengan metode maserasi menggunakan pelarut etanol 96% setelah itu ekstrak diidentifikasi kandungan metabolitnya dan diujikan aktivitas antifungi. Pengujian aktivitas antifungi emnggunakan metode difusi cakram dengan konsentrasi ekstrak sebesar 10%, 20% dan 30%. Kontrol positif yang digunakan adalah ketokonazol 15µg/disk dan kontrol negatif berupa DMSO. Analisis data menggunakan SPSS yaitu uji kruskal wallis dan uji Duncan. Hasil penelitian menunjukkan bahwa ekstrak Mikania micrantha dapat menghambat pertumbuhan T. mentagrophytes pada konsentrasi 10%, 20%, dan 30% masing-masing sebesar 6,01 mm,6.51 mm dan 7,05 mm. Sementara pada T.rubrum konsentrasi 10%, 20% dan 30% rata-rata zona hambat masing-masing sebesar 5,68 mm, 6,01 mm, dan 6,51 mm. Hasil uji statistik dengan menggunakan ujikruskal-wallis nilai P-value T.mentagrophytes sebesar 0.042 dan T.rubrum sebesar 0.087 dan pada uji Duncan hasil yang didapat bahwa tidak ada perbedaan yang signifikasi antara zona hambat dengan konsentrasi ekstrak yang diujikan. Keywords: Antifungi; Mikania micrantha; Trichophyton mentagrophytes; Trichophyton rubrum.

Experience Professional dermatomycosis of the face, neck and upper part of chest caused by T. mentagrophytes

A 43-year-old female zoologist has an occupational dermatomycosis of the face, neck and upper part of chest caused by T. mentagrophytes. It was mistakenly diagnosed and treated as "Rosacea, papulopustular subtype, ocular rosacea" for 1.5 years. Symmetrical, atypical clinical manifestations with recurrent blepharoconjunctivitis developed as a result of self-treatment using a topical steroid. The detection of cicatrizing folliculitis in the eyebrow area and an arcual peripheral edge in fresh foci on the chest helped to suspect dermatomycosis. The definitive diagnosis was made after the detection of abundant coarse septate mycelium during microscopic investigation of skin scales from foci on the face and chest with 30% KOH and an abundant growth of Trichophyton mentagrophytes during a cultural research study of skin scales, eyebrow hair and eyelashes from lesions. The use of terbinafine for 4 weeks led to the recovery of the patient.

Sterically Hindered Quaternary Phosphonium Salts (QPSs): Antimicrobial Activity and Hemolytic and Cytotoxic Properties

Structure–activity relationships are important for the design of biocides and sanitizers. During the spread of resistant strains of pathogenic microbes, insights into the correlation between structure and activity become especially significant. The most commonly used biocides are nitrogen-containing compounds; the phosphorus-containing ones have been studied to a lesser extent. In the present study, a broad range of sterically hindered quaternary phosphonium salts (QPSs) based on tri-tert-butylphosphine was tested for their activity against Gram-positive (Staphylococcus aureus, Bacillus сereus, Enterococcus faecalis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria and fungi (Candida albicans, Trichophyton mentagrophytes var. gypseum). The cation structure was confirmed to determine their biological activity. A number of QPSs not only exhibit high activity against both Gram-positive and -negative bacteria but also possess antifungal properties. Additionally, the hemolytic and cytotoxic properties of QPSs were determined using blood and a normal liver cell line, respectively. The results show that tri-tert-butyl(n-dodecyl)phosphonium and tri-tert-butyl(n-tridecyl)phosphonium bromides exhibit both low cytotoxicity against normal human cells and high antimicrobial activity against bacteria, including methicillin-resistant strains S. aureus (MRSA). The mechanism of QPS action on microbes is discussed. Due to their high selectivity for pathogens, sterically hindered QPSs could serve as effective tunable biocides.