Study of the incidence of hospital infection (Part 3)

Study of the incidence of hospital infection (Part 3)

Saturday March 10th, 2018

Since hospitals are the most important center for providing health services, due to the special conditions for admitting people with various diseases, the existence of different service providers, patients’ visitors and their companions, they are considered as an infection transmission center. Technological advances, reduced human resistance, the emergence of new drugs and, consequently, reduced body resistance have added to the diversity and number of hospital infections. Due to the importance of this problem and the lack of accurate statistics on hospital infection in the country, especially in Qom province this study was carried out on patients admitted to one of the large Qom hospitals in 2007. In contrast to international statistics and the discovery of mistakes in the service system, the results of this study led us to clarify specific provisions to reduce the mortality rate of hospitalized patients with nosocomial infections.

Materials and methods:

This research is an incidence study and the data has been collected prospectively. The population under study was patients admitted to CCU and ICU.

Men and women surgery, nephrology, infants and infection instances of one of the hospitals in Holy City of Qom during 2007-2009 were 2931 cases. At the beginning of the study, questionnaires were prepared and adjusted. All of the instructions related to the diagnosis of nosocomial infections were given to the nurses working in the wards, especially the head nurses. Then with direct supervision of the physician and nurse responsible for infection control, the patients with general clinical conditions and symptoms including fever, weakness, anemia, skin rashes and muscle aches and specific symptoms, including urinary tract infections, pulmonary infection and skin infections that occurred after 48 hours of hospitalization were isolated and examined.

Specific specimens of wounds, sputum, blood and urine were collected from these patients and their connected components (eg, angioplasty, catheter, catheter, etc.) and transferred to the laboratory, several smears were prepared from each sample and gram staining and GIMSA was done simultaneously. To culture urine sample, the blood and MacConkey agar EMB were used and blood culture was done in Csataneda TSB fluid media and lysis centrifugation. In sputum culture, the blood and MacConkey agar and in wound culture, the blood and chocolate agar were used. To detect fungi in samples, Sabrouraud dextrose agar was used. After 24 hours of incubation, differential, catalase, oxidase, coagulase, indole, SIM, TSI, MRVP, citrate and urease diagnostic tests were used to identify bacteria in species level. After examination of samples directly and expanding them, if fungi was observed it was cultured in Sabrouraud dextrose agar together with chloramphenicol and dextrose-malt agar with chloramphenicol and incubation was performed after 24 hours for yeast and one week for saprophytes.

Then, yeast samples were confirmed by biochemical assay and chromogenic agar culture medium. Saprophyte specimens were confirmed by observation of direct cultured specimen and preparation of culture slide. Then, the obtained information along with the information in each section were recorded in each part of hospital information software (HIS) in terms of name, age, sex, hospitalization date, hospitalization department, cause of hospitalization, hospital infection, location of incidence of hospital infection, date of the incidence of hospital infection and the type of laboratory sample from the questionnaire. To calculate the number of patients-the day of admission, the length of stay of patients was multiplied by the number of patients in each department. To determine the incidence density, the number of diagnosed nosocomial infection in 2007 was divided by the total number of patients – the day of admission and mentioned as ten thousand patients. The incidence of nosocomial infection was mentioned as the number of nosocomial infection cases divided by the total number of hospitalized patients during the year 2007 using SPSS software.


In 2007-2008, 105 patients with nosocomial infections were diagnosed based on hospital care parameters among different departments among which 50 were female (47.61) and 55 were male (52.38). The mean age was 64.16 ± 26.4 years with the age range of a few months to 121 years that 10.16% (12 patients) were less than 30 years old, 23.72% (28 patients) were 30 and 59 years, and67.79% (80 patients) were over 60 years of age. The incidence of hospital infection in 2007 was 35 in 10,000 patients. Regarding the duration of the research, the annual incidence of hospital infection is 0.35%. In Table 1, which is presented in the next article, the frequency distribution of patients, the patient rate-admission day, rate of incidence and incidence density are presented in terms of hospital departments.