Introduction. The commonly used term "hospital-acquired infection" may suggests that it only apply to hospitals, however, infections can also spread in medical offices or outpatient clinics. Therefore, the more appropriate name is: healthcare-associated infections (HAI). Regardless of where such an infection occurs, the primary goal of the organization of surveillance of infections is to prevent these infections / invasions. According to the World Health Organization, the percentage of nosocomial infections caused by various etiological factors should be between 5 and 10%. Aim. The aim of the study was to analyze the registered cases of nosocomial infections 2005-2015, based on data from the district hospital in the Łódź region. Materials and methods. The presented data come from internal reports made by the hospital infection control committee Results. Despite the modernization of the hospital in 2014, the total number of nosocomial infections has almost tripled in 2015 (72 patients, 0.87% of all hospitalized). The most frequently registered etiologic agent of nosocomial infections over 10 years was Staphylococcus aureus, however in 2015 this number significantly decreased and infections caused by Escherichia coli, Enterococcus faecium and Klebsiella pneumoniae were the most common agents responsible of hospital-acquired infection. The reports showed that the Klebsiella pneumoniae ESBL were ranked first among pathogenic factors classified as alarm agents. Conclusions. Hospital infections are still a current problem for the health care system, but in recent years infection caused by drug-resistant bacteria has come to the fore.

Key words: nosocomial infections, prevalence, alarm pathogens.