Nosocomial Infection in a Teaching Hospital in Thailand

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1 Nosocomial Infection in a Teaching Hospital in Thailand Somsak Lolekha, M.D., Ph.D.,* Banchong Ratanaubol R.N.** and Pranom Manu R.N.** (*Department of Pediatrics; **Department of Nursing, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand) No Abstract Available [Phil J Microbiol Infect Dis 1981; ] Key Words: nosocomial, infection, surveillance, epidemiologist INTRODUCTION A nosocomial infection in any infection acquired during hospitalization that was neither present nor incubating at the time of the patient's admission to the hospital. It may become clinically apparent either during the hospitalization or after discharge. 1 Nosocomial infection is a major infectious disease problem in most hospitals today. A previous study at Ramathibodi Hospital revealed that nosocomial infection prolonged hospital stay by approximately one to two weeks. 2 Patients with nosocomial infection had two to three times higher in mortality and prolonged hospitalization. Nosocomial infection is a difficult therapeutic problem. The patients who acquire such infection often are compromised hosts with an underlying disorder of host defense. Pathogens causing nosocomial infection are often resistant to standard antimicrobials, thereby making therapy more difficult and expensive. An understanding of the epidemiology of nosocomial infections is necessary for effective control and prevention measures. METHODS Two full-time hospital nurse epidemiologists, as part of their regular duties, have performed nosocomial infection surveillance in the department of medicine, surgery, gynecology and pediatrics since The surveillance methods were adopted from recommendations published by the Center for Disease Control. 3 In summary, the collection of information were obtained by a) ward rounds at least twice a week, conferring with head nurses regarding patients admitted with infections as well as patients who acquired infections in hospital; b) daily contact with the clinical microbiology laboratory regarding cultures positive for potential pathogens, with follow-up to determine whether these bacteria were associated with clinical infections; c) review of admission records to establish the rate of community-acquired infection; d) maintenance of records regarding infections and review of accumulated information. A monthly summary report of nosocomial infections prepared by the infection control nurse is distributed to the medical staff and appropriate members of the nursing staff to keep them informed of problems and progress in the infection control program. The classification system and criteria for infections were those suggested by the National Nosocomial Infections Study. 3 Diagnostic virology was not routinely done in this study. RESULTS During the three-year period of 1978 to 1980, there were 22,053 patients in the department of medicine, surgery gynecology and pediatrics under surveillance. There were 2,467 nosocomial infections (11.2 per 100 discharges) among 2,110 patients (9.6 per 100 discharges). The incidence of community acquired and hospital-acquired infections during 1978 to 1980 in Ramathibodi majority of the patients admitted to medical and pediatric ward had

2 community acquired infection on admission (81.9% and 71.9% respectively). This indicated the high prevalence of infectious diseases in Thailand. There were 38.6% and 35.2% of patients admitted to the department of surgery and gynecology had evidence of community acquired infection on admission. The incidence of nosocomial infection was highest in the department of medicine (16.1%) and lowest in the department of pediatrics (7.2%), (Table 1). The incidence of community acquired and hospital acquired infection varied very little from year to year (Table 2). In 1980 there was a slight decrease in the incidence of nosocomial infection in every department. Table 1. Incidence of Community Acquired and Nosocomial Community Acquired Infection Nosocomial Infection Department Number of Patients Discharged No % No % Medicine 4,219 3, Surgery 6,975 2, Gynecology 4,058 1, Pediatrics 6,801 4, Total 22,053 12, , Table 2. Rate of Community Acquired Infections in Ramathibodi Hospital by Years ( ) Community Acquired Infection Nosocomial Infection Department Medicine 82.0* Surgery Gynecology Pediatrics * per 100 discharges Table 3 showed the rates of nosocomial infection according to site and service. Urinary tract infection was the most common cause and surgical wound was the second most common nosocomial infection in the department of medicine and pediatrics followed by respiratory tract infection and bacteremia. Nosocomial gastrointestinal tract infection was an important problem in the department of pediatrics only. There was an outbreak of Salmonella krefeld gastroenteritis in pediatrics wards in The major problems of nosocomial infection in the department of surgery and gynecology were urinary tract infection and surgical wound infection. Table 3. Rate of Nosocomial Infections According to site and Service in Ramathibodi Hospital ( ) Department Bacteriuria Respiratory tract Gastro intestinal Surgical Wound Other cutaneous Bacteremia Other Total Medicine Surgery Gynecology Pediatrics Total 1, ,467 Almost half of nosocomial infections were due to urinary tract infection. It occurred in about one out of 20 patients hospitalized at Ramathibodi Hospital (Table 4). Nosocomial pneumonia represented 10.3 percent of the total nosocomial infections, and the rate of nosocomial pneumonia was 1.1 percent of all discharges. The incidence of nosocomial bacteremia was 9 cases per 1000 discharges. Eighty percent of nosocomial urinary tract infections were caused by Klebsiella species, Escherichia coli, Enterobacter species, Pseudomonas aeruginosa and Proteus species, (Table 5). Gram negative bacilli accounted for 90 percent of urinary tract infection.

3 Table 4. Rate and Type of Nosocomial Infection Type of Infection Percent of Total Nosocomial Infections Infections Per 100 Discharges Urinary tract infection Surgical wound infection Other cutaneous (bed sore, abscess cellulitis etc.) Respiratory tract infection Bacteremia Gastroenteritis Others Total Table 5. Organisms Isolated from Nosocomial Urinary Tract Infection ( ) Klebsiella Escherichia coli Enterobacter species Pseudomonas aeruginosa Proteus species Acinetobacter var anitratus Candida species Streptococcus pyogenes Staphylococcus aureus Enterococcus Staphylococcus epidermidis Citrobacter species Serratia marcescens Acinetobacter var lwoffi Salmonella species Pseudomonas cepacia Others Total 1717 Organisms isolated from nosocomial surgical wound infection are shown in Table 6. Out of 308 cases that cultures were taken from the infected sites, Escherichia coli was found in 107 cases (34.7%). Klebsiella species and Pseudomonas aeruginosa was found in 71 and 67 cases respectively. Staphylococcus aureus was found in 45 out of 308 cases. Table 6. Organisms Isolated from Nosocomial Urinary Tract Infection ( ) Escherichia coli Klebsiella species Pseudomonas aeruginosa Staphylococcus epidermidis Proteus species Staphylococcus aureus Streptococcus pyogenes Enterobacter species Acinetobacter var anitratus Enterococcus Serratia marcescens Others Not cultured

4 Organisms isolated from patients with nosocomial respiratory tract infection are shown in table 7. Pseudomonas aeruginosa and Klebsiella pneumoniae accounted for 61 percent of organisms isolated from patients with lower respiratory tract infection. Staphylococcus aureus was found in 11 out of 253 cases (4%) of nosocomial pneumonia. Seventy three percent of organisms isolated from patients with nosocomial bacteremia were due to gram-negative bacilli. Klebsiella species, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and enterobacter were the most common organisms causing nosocomial bacteremia (Table 8). Table 7. Organisms Isolated from Nosocomial Respiratory Tract Infection ( ) Pseudomonas aeruginosa Klebsiella pneumonia Escherichia coli Acinetobacter vat anitratus Enterobacter species Serratia marcescens Staphylococcus aureus Pseudomonas cepacia Enterococcus Proteus species Candida species Others Total 350 Table 8. Organisms Isolated from Nosocomial Septicemia ( ) Klebsiella species Pseudomonas aeruginosa Escherichia coli Staphylococcus aureus Enterobacter species Staphylococcus epidermidis Acinetobacter vat anitratus Candida species Bacillus species Streptococcus pyogenes Salmonella species Proteus species Serratia marcescens Aeromonas hydrophila Pseudomonas cepacia Enterococcus Citrobacter species Others Total DISCUSSION The high incidence of community-acquired infections in this report reflects the nation wide problem of infectious diseases. The average incidence of nosocomial infection is 9.6 cases per 100 discharges. It varies according to times and services from 6.0 to 17.9%. The overall prevalence of nosocomial infection in the United States and United Kingdom varies between 3.5

5 and 16.8 per 100 admissions, 4 the lower figures being observed in community hospitals, and the higher figures in large city hospitals and university hospitals. The rate of nosocomial urinary tract infection is 5 per 100 discharges and it accounts for 46.8% of all nosocomial infections. Composite data from the National Nosocomial Infections Study (NNIS) in the United States indicate that about 40 percent of all nosocomial infections reported in 1971 through 1974 involved urinary tract and that the overall rate for such infections was 1.4 per 100 hospital discharges. 5 The incidence of nosocomial urinary tract infection in our study was higher than the NNIS, since we did not include the service which had lower incidence of urinary tract infection such as ENT, ophthalmology etc. in our study. However, the incidence of nosocomial urinary tract infection in our hospital in 1980 was about half of the data in Prepared technique in the use of the closed-drainage system may account for this decrease in incidence. The rate of nosocomial urinary tract infections depends mostly on the frequency of conditions in patients that lead to instrumentation of the urinary tract and the policies and procedures of the medical care system in the hospital. Nosocomial pneumonia represents 10 percent of the total nosocomial infections, and the rate of nosocomial pneumonia was 1.1 percent per 100 discharges. This data is comparable to other published data, which reveal nosocomial pneumonia represented 8 to 33 percent of the total nosocomial, infections, and the rate of nosocomial pneumonia varies for 0.5 percent to 5.0 percent of all discharges. 4 The incidences in community hospitals generally has been two to ten times lower than in university affiliated teaching hospitals. These references may reflect social factors. University hospitals tend to be tertiary care centers to which the more sick, complicated patient is referred, support procedures may be more advanced, and teaching hospitals often have individuals involved in patient care who are students and who may be less knowledgeable and skilled in those aspects of care important in the prevention of nosocomial infections. Nosocomial bacteremia is the most serious of all nosocomial infection with very high mortality rate. It occurred in 0.9 per 100 hospital discharges. Most of these patients were compromised host with underlying malignancy or neutropenia. The major sources of infections include urinary tract infection, IV contamination and ulceration of gastrointestinal tract. About 70 to 80 percent of all nosocomial infections are caused by gram-negative bacilli. Klebsiella species are the most common cause of nosocomial urinary tract infection and septicemia. The etiologic organisms vary from hospitals. It depends on the pattern of antimicrobial usages and colonization of the organisms in the hospital environment. Pseudomonas aeruginosa and Escherichia coli are the most common cause of nosocomial pneumonia and surgical wound infection respectively. The leading cause of nosocomial infection in this study includes three organisms, Klebsiella species, Pseudomonas aeruginosa and Escherichia coli. With the broader spectrum of antimicrobial agents used in the hospital, we observed the rising in the incidence of candida infection in our hospita l, Although immunocompromised patient are clearly far more susceptible to nosocomial infection, the incidence of nosocomial infection can be reduced by emphasizing the importance of hand washing practices and aseptic technique. Avoid using unnecessary instrumentations for diagnosis and therapy. The proper use of antimicrobial agents for suspected infection or prophylaxis will reduce the colonization of multiple drug resistant bacteria in the hospital and reduces the rate of surgical infection. Every hospital should have hospital infection control committee to establish policy on aseptic technique, isolation, sterilization and disinfection. Effective surveillance program on nosocomial infection should be done on high-risk wards in order to detect any outbreak of nosocomial infection and try to control it as soon as possible. Most exogenous nosocomial infections result from personal contact, some results from contamination of the physical environment. This contamination can be prevented and controlled by careful attention to cleanliness and sanitation. Environmental microbiological sampling programs may be useful in some situations. The hospital infection control program should be designed to protect both patients and personnel. Thus, an effective employee health service is

6 needed to perform such important control functions as the detection, evaluation, prevention, and treatment of infection in personnel. Augmentation of host defense mechanism in patients, prevention of colonization of nosocomial pathogens and enhancing the safety to invasive procedures and devices will reduce the incidence of nosocomial infection in the future. However, the most important factor of all is the awareness of nosocomial infection and knowledge of infection control nosocomial infection to the lowest level. REFERENCES 1. Dixon RE. Nosocomial infection, a continuing problem. Postgrad Med 1977; 62: Lolekha S. Nosocomiai infection, Bangkok. Aksomsampan (Thai). 3. Garner JS, Bennett JV, Scheckler WE, Maki DC, Brachman PS. Surveillance of nosocomial infections. Proceedings of the International Conference on Nosocomial Infection, Chicago. Am Hosp Assoc1971: Sanford JP, Pierce JP. Current infection problems-respiratory. Proceedings of the International Conference on Nosocomial Infection, Chicago. Am Hosp Assoc 1977: Kunin CM. Urinary tract infection. In: Bennett Jr, Brachman PS (eds.). Hospital Infection. Boston: Little, Brown and Company, pp

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