Commonest cause of nosocomial infection
High-Yield Explanation
Controversial MCQ, no where there is clear cut reference for MC agent of HAI
Initially hospital outbreaks were caused by Gram positive organisms like Streptococcus pyogenes and the methicillin resistant Staphylococcus aureus (MRSA)
Presently Gram negative enteric pathogens (Enterobacteriaceae) including Escherichia coli, Klebsiella and Enterobacter species have emerged as an important cause
Pseudomonas and Acinetobacter species are also common nosocomial pathogens and are extremely resistant to common antibiotics and antiseptics.