Department of Medical Microbiology, Shi-Gan International College of Science and Technology, Tribhuvan University, Shankhamarg, Kathmandu, Nepal.
Department of Pathology, Nepal Armed Police Force Hospital, Balambu, Kathmandu, Nepal.
J Nepal Health Res Counc. 2024 Oct 3;22(2):410-418.
The ability of Staphylococcus aureus to form biofilmsâ€"architectural complexes that cause chronic and recalcitrant infectionsâ€"along with its notorious variant, methicillin-resistant Staphylococcus aureus (MRSA), leads to multidrug-resistant (MDR) infections that are challenging to treat with antibiotics. This cross-sectional study investigated the prevalence of S. aureus infections in Kanti Children’s Hospital and characterized the antibiograms of MDR, MRSA, and biofilm-forming strains, along with their coexistence.
S. aureus strains were isolated and identified from clinical samples and tested for antibiograms following standard microbiology guidelines. MDR strains were non-susceptible to at least one agent in three antimicrobial categories, whereas MRSA strains were cefoxitin-resistant. The microtiter plate method was used to detect biofilms. Statistical analyses were performed using SPSS version 17.0.
S. aureus was detected in 9.0% (11.4-6.6%, 95% Confidence Interval) of 543 samples, primarily from pus (79.6%, 39/49). Children aged 1 to <3 years most commonly contracted infections (30.6%, 15/49), and males (67.4%, 33/49) had twice as many infections as females (32.7%, 16/49). As high as 84.7% (83/98) of strains were penicillin-resistant, while 18.4% (27/147) were aminoglycoside-resistant. MDR accounted for 79.6% (39/49) of all S. aureus infections, while MRSA and biofilm-formers accounted for 67.6% (33/49) and 24.5% (12/49), respectively. Fluoroquinolone resistance in non-MDR-MRSA-biofilm-formers, MDR-MRSA, MDR-biofilm-formers, and MRSA-biofilm-formers was 31.3%, 46.8%, 58.3%, and 60.0%, respectively, while aminoglycoside resistance was 0%, 32.3%, 50.0%, and 45.0%, and penicillin resistance was 87.5%, 85.5%, 100.0%, and 100.0%.
MDR-isolates and MRSA caused nearly four-fifths of S. aureus infections. Compared to MDR and MRSA strains, biofilm-formers triggered higher levels of antimicrobial resistance.
金黄色葡萄球菌能够形成生物膜——一种导致慢性和难治性感染的建筑复合物——以及其臭名昭著的变体耐甲氧西林金黄色葡萄球菌（MRSA），导致对抗生素具有多药耐药性（MDR）的感染，这使得治疗变得具有挑战性。本横断面研究调查了坎蒂儿童医院金黄色葡萄球菌感染的流行情况，并对 MDR、MRSA 和生物膜形成株的抗生素耐药谱进行了特征描述，以及它们的共存情况。
按照标准微生物学指南，从临床标本中分离并鉴定金黄色葡萄球菌菌株，并检测其抗生素耐药谱。MDR 菌株对三种抗菌药物类别中的至少一种药物不敏感，而 MRSA 菌株对头孢西丁耐药。使用微量滴定板法检测生物膜。使用 SPSS 版本 17.0 进行统计分析。
在 543 份样本中，金黄色葡萄球菌的检出率为 9.0%（95%置信区间为 6.6%至 11.4%），主要来自脓液（79.6%，39/49）。1 至<3 岁的儿童最常发生感染（30.6%，15/49），男性（67.4%，33/49）的感染人数是女性（32.7%，16/49）的两倍。高达 84.7%（83/98）的菌株对青霉素耐药，而 18.4%（27/147）对氨基糖苷类耐药。MDR 占所有金黄色葡萄球菌感染的 79.6%（39/49），而 MRSA 和生物膜形成株分别占 67.6%（33/49）和 24.5%（12/49）。非 MDR-MRSA-生物膜形成株、MDR-MRSA、MDR-生物膜形成株和 MRSA-生物膜形成株的氟喹诺酮耐药率分别为 31.3%、46.8%、58.3%和 60.0%，氨基糖苷类耐药率分别为 0%、32.3%、50.0%和 45.0%，青霉素耐药率分别为 87.5%、85.5%、100.0%和 100.0%。
MDR 分离株和 MRSA 引起了近五分之四的金黄色葡萄球菌感染。与 MDR 和 MRSA 菌株相比，生物膜形成株引发了更高水平的抗菌药物耐药性。
