Multidrug-resistant hospital-associated infections in a
pediatric intensive care unit: a cross-sectional survey
in a Thai university hospital
Suchada Sritippayawan
*
, Klaita Sri-Singh, Nuanchan Prapphal,
Rujipat Samransamruajkit, Jitladda Deerojanawong
Division of Pulmonology and Critical Care, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Rd, Bangkok 10330, Thailand
Received 7 December 2007; received in revised form 1 June 2008; accepted 25 August 2008 Corresponding Editor: Ziad Memish, Riyadh, Saudi Arabia
Introduction
Multidrug-resistant hospital-associated infections (MDR-HAI) are increasing worldwide, especially among those who are admitted to the intensive care unit (ICU), and can be a major cause of morbidity and mortality in these patients. Several
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KEYWORDS
Multidrug-resistant; Hospital-associated infection;
Pediatric intensive care unit
Summary
Objective: To determine the incidence and associated factors of multidrug-resistant hospital-associated infections (MDR-HAI) in a pediatric intensive care unit (PICU) of a university hospital in Thailand.
Method: A prospective study was performed in the PICU of King Chulalongkorn Memorial Hospital during the period May—December 2005. Children aged15 years who developed a PICU-related HAI were studied.
Results: Forty-four patients (median age 6 months; male:female = 1.4:1) developed 58 episodes of PICU-related HAI. The HAI rate was 28.3 per 1000 patient-days. Thirty episodes (52%) were MDR-HAI. The following were found more frequently in MDR-HAI when compared to non-MDR-HAI: Acinetobacter baumannii (50% vs. 23%, p = 0.04), female sex (60% vs. 29%, p = 0.02), admission to the PICU with a medical condition (90% vs. 64%, p = 0.03), PICU stay longer than 7 days prior to the development of HAI (67% vs. 36%, p = 0.03), and previous use of broad-spectrum antibiotics (83% vs. 43%, p = 0.002). Independent risk factors for MDR-HAI included female sex (OR = 5.5, p = 0.03) and previous use of a broad-spectrum antibiotic (OR = 9.7, p = 0.01).
Conclusion: The incidence of MDR-HAI was high in the PICU. Female sex and previous use of a broad-spectrum antibiotic were independent risk factors for MDR-HAI.
#2008 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
* Corresponding author. Tel.: +66 2 256 4951; fax: +66 2 256 4911. E-mail address:suchadacu@hotmail.com(S. Sritippayawan).
1201-9712/$36.00 # 2008 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijid.2008.08.022
studies have reported the incidence and associated factors of MDR-HAI in the adult ICU.1—6However, studies in the pedia-tric ICU (PICU) are scarce, especially among those in South-east Asian countries. Most of the studies in pediatrics have focused on specific HAI and MDR-HAI caused by some specific etiologic agents.7—12 The incidence, etiologic agents, and
associated factors of MDR-HAI can vary among PICUs and are important for the development of appropriate HAI control measures in each patient care setting. We therefore under-took this study to determine the incidence and associated factors of MDR-HAI in a PICU of a university hospital in Thailand.
Patients and methods
Study design and setting
A prospective study was performed on children aged 15 years who were admitted to the PICU of King Chulalongkorn Memorial Hospital during the period May—December 2005. The study protocol was approved by the Ethics Committee for Human Research Study of Chulalongkorn University.
King Chulalongkorn Memorial Hospital is a tertiary-care university hospital in Thailand. There is one PICU that serves medical and surgical pediatric patients aged up to 15 years, except neonates aged less than 72 hours. The PICU setting is a 10-bed unit divided into two five-bed subunits and four single-patient rooms for immunocompromised patients and those who have specific infectious diseases that need isola-tion. The bedside care medical staff consist of one full-time pediatric pulmonologist who is a PICU attending, one pedia-tric pulmonary fellow, and four to five pediapedia-tric residents. The nursing staff provide bedside patient care on a one-on-two basis (one nurse per one-on-two patients) during the daytime and nighttime shifts. Patient care and antibiotic use are decided by the attending PICU physicians. No authorization from the infectious disease specialist is required prior to the prescrip-tion of broad-spectrum antibiotics.
Infection control measures are set and monitored by the Hospital Associated Infection Control Committee of the hos-pital. The guidelines are set according to those of the Centers for Disease Control and Prevention (CDC).13 Hygienic hand
washing with soap and water or alcohol-based hand rub before and after each patient contact is encouraged for all healthcare personnel who are working in the PICU and the family members who come to visit the patients. Alcohol-based hand rub is provided at the bedside for each bed and at the entrance to the PICU. There are two hand-washing sinks per five patient beds and one for each single-patient room. All healthcare workers are encouraged to use gloves when in contact with the patient or patient body fluids, secretions, and excretions. Gowns and goggles are not routinely used except in situations where there is a risk for body fluid, secretion, or excretion contamination. The respiratory ther-apy equipment is cleaned and sterilized according to the CDC guidelines.14Ventilator circuit and humidifiers are changed
every 48 hours. Water used for humidifiers and nebulizers is changed every 8 hours. Small-volume medication nebulizers are restricted to single-patient use only. No sharing between patients is allowed unless there has been appropriate rest-erilization. Following each use in the same patient, they are
cleaned with soap and water, and they exchanged with a sterilized replacement once every day.
Definitions
PICU-related HAI was defined as any infection that was not present or incubating at the time of PICU admission but occurred at 48 hours or more after admission to the PICU.15 To calculate the HAI rate, we collected the number of patients in the PICU and the total number of patient-days of stay on a monthly basis. The percent of HAI and the number of HAI per patient-days were calculated by dividing the total number of PICU-related HAI pooled throughout all the months by the total number of PICU patients (100) and patient-days (1000), respectively.
The specific HAI-type was diagnosed according to the criteria set by the CDC.16 Device-associated HAI such as ventilator-associated pneumonia (VAP), catheter-related bloodstream infection (CR-BSI), and catheter-related urin-ary tract infection (CR-UTI) were diagnosed if the patient developed clinical signs and symptoms of pneumonia, blood-stream infection, and urinary tract infection (as per CDC criteria), respectively, after being on mechanical ventila-tion or having the indwelling device for at least 48 hours. Etiologic agents were identified from cultures obtained from the related sites suggested by the CDC, except for nosoco-mial pneumonia where the cultures were obtained from endotracheal aspirates.
Antimicrobial susceptibility was identified using the Kirby—Bauer disk diffusion method. We defined MDR-HAI as any HAI caused by any of the following organisms: (1) Steno-trophomonas maltophilia (no matter what the antibiotic susceptibility pattern was); (2) Acinetobacter spp that were resistant to beta-lactam/beta-lactamase inhibitors, tri-methoprim—sulfamethoxazole, and at least one from each of the following antibiotic classes: aminoglycoside, ciproflox-acin, piperacillin, third-/fourth-generation cephalosporin, and carbapenem; (3) other aerobic Gram-negative rods (GNR) including Enterobacteriaceae and Pseudomonas that were resistant to three or more of the following antibiotic classes: beta-lactam/beta-lactamase inhibitors (only for Enterobacteriaceae), at least one aminoglycoside, ciproflox-acin, piperacillin, third-/fourth-generation cephalosporin, and carbapenem; (4) methicillin-resistant staphylococci; (5) vancomycin-resistant enterococci.
Broad-spectrum antibiotics included piperacillin/tazo-bactam, ceftazidime, cefepime, ciprofloxacin, imipenem/ cilastatin, meropenem, and sulbactam/cefoperazone.
Collected data
During the study period, all patients in the PICU were mon-itored for HAI. Patients were monmon-itored daily until discharge from the PICU or death. Collected data included age, gender, underlying diseases, nutritional status, indication for PICU admission, referral from another PICU, length of PICU stay prior to the development of HAI, types of invasive procedures performed (such as endotracheal intubation, nasogastric catheterization, central venous catheterization, arterial catheterization, urinary catheterization, intravenous parent-eral nutrition), types and duration of stress ulcer prophylaxis,
sites of HAI, antibiotics prescribed within the last 15 days prior to the development of HAI, isolated organisms related to HAI and their antibiotic susceptibility patterns, length of PICU stay, and final outcome of the patients during PICU stay (survived or died).
Data acquisition and analysis
The patients were divided into two groups, MDR-HAI and non-MDR-HAI, on the basis of the susceptibility patterns of the isolated organisms related to the HAI. Continuous variables were compared between the two groups using the Student’s t-test or Mann—Whitney U-test where applic-able. Categorical variables were compared using the Chi-square test or Fisher’s exact test. Multiple logistic regres-sion analysis was used to identify the independent factors associated with MDR-HAI. All potential risk factors showing a p value of <0.2 in the univariate analysis were included in the regression model. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. A two-tailed p-value of <0.05 was considered statistically significant. The statistical analysis was performed using GraphPad Instat Program (GraphPad Software Inc., San Diego, CA, USA) and SPSS version 13.0 for Windows (SPSS Inc., Chi-cago, IL, USA).
Results
During the study period, 347 patients were admitted to the PICU. The total patient-days was 2052 days. Forty-four patients (median age 6 months, range 4 days—14 years; male:female = 1.4:1) developed 58 episodes of HAI during their PICU stays. Thirty-four patients (77%) were aged under 5 years. The HAI rate was 16.7%, equiva-lent to 28.3 HAI per 1000 patient-days. Among the 58 episodes of PICU-related HAI, 30 episodes (52%) were caused by MDR organisms (MDR-HAI), while 28 episodes (48%) were caused by non-MDR organisms (non-MDR-HAI). Indications for PICU admission were pneumonia with respiratory failure (51%), post-surgery (22%), sepsis (21%), and others (6%).
Types of HAI
Of the total of 44 patients who developed HAI during their PICU stay, all were intubated and on a mechanical ventilator (34 episodes of VAP were observed). Forty-one patients (93%) had a central venous catheter insertion (11 episodes of CR-BSI were observed), while 30 patients (68%) had a urinary cathe-ter placement (five episodes of CR-UTI were observed). Eight episodes of PICU-related HAI were surgical site infections. VAP was the most common HAI found in both the MDR-HAI and non-MDR-HAI groups (67% and 54%, respectively). There was no statistical difference between the MDR-HAI and non-MDR-HAI groups with regard to non-MDR-HAI type (data not shown).
Isolated organisms
GNR were the most commonly isolated organisms associated with PICU-related HAI (48/62 isolations, 77%). Others included staphylococci (9/62 isolations, 15%) and entero-cocci (5/62 isolations, 8%). Acinetobacter baumannii was the most commonly isolated GNR. Sixty-four percent (16/ 25 isolations) of Acinetobacter and 58% (7/12 isolations) of Pseudomonas were MDR. All of them were resistant to car-bapenem. Among the nine isolated staphylococci, one (11%) was methicillin-resistant Staphylococcus aureus (MRSA) and two (22%) were methicillin-resistant coagulase-negative sta-phylococci. Forty percent of isolated enterococci (2/5 iso-lations) were vancomycin-resistant (Table 1). A. baumannii was found more frequently in the MDR-HAI group than in the non-MDR-HAI group (50% vs. 23%; p = 0.04) (Table 1).
Isolated organisms associated with each type of HAI
Among 34 episodes of VAP, the most commonly isolated organism was A. baumannii (16 episodes, 47%). Others included Pseudomonas aeruginosa (eight episodes), Kleb-siella pneumoniae (three episodes), other Pseudomonas spp (three episodes), coagulase-negative staphylococci (three episodes), enterococci (one episode), Enterobacter (one episode), and S. aureus (one episode).
Table 1 Isolated organisms related to hospital-associated infections (total number of isolations = 62).
MDR-HAI (n = 32) non-MDR-HAI (n = 30) p-Value OR (95% CI) Isolated organisms related to nosocomial infection (%)
Gram-negative rods Acinetobacter baumannii 16 (50%) 7 (23%) 0.04 3.3 (1.1—9.8) Pseudomonas aeruginosa 5 (16%) 4 (13%) 1.0 1.2 (0.3—5.0) Klebsiella spp 3 (9%) 3 (10%) 1.0 0.9 (0.2—5.0) Enterobacter spp 1 (3%) 2 (7%) 0.6 0.5 (0.03—5.3) Other Pseudomonas spp 2 (6%) 1 (3%) 1.0 1.9 (0.2—22.5) Escherichia coli 0 2 (7%) 0.2 0.2 (0.0—3.8) Acinetobacter lwoffii 0 2 (7%) 0.2 0.2 (0.0—3.8) Staphylococcus spp Staphylococcus aureus 1 (3%) 0 1.0 2.9 (0.1—74.2) Coagulase-negative staphylococci 2 (6%) 6 (20%) 0.1 0.3 (0.05—1.4) Enterococcus spp 2 (6%) 3 (10%) 0.7 0.6 (0.1—3.9)
Regarding those who developed CR-BSI (11 episodes), the most commonly isolated organisms were A. baumannii (four episodes, 36%) and coagulase-negative staphylococci (four episodes, 36%). Others included Acinetobacter lwoffii (two episodes), K. pneumoniae (one episode), and enterococci (one episode).
In the PICU-related surgical site infection group (eight episodes), the most commonly isolated organism was A. baumannii (three episodes, 38%). Others included enterococci (two episodes), K. pneumoniae (one episode), P. aeruginosa (one episode), coagulase-negative staphylococci (one episode), and Escherichia coli (one episode).
The isolated organisms associated with CR-UTI (five epi-sodes) were Enterobacter (two episodes, 40%), Enterococcus (one episode), K. pneumoniae (one episode), and E. coli (one episode).
There were two episodes of VAP, one episode of CR-BSI, and one episode of surgical site infection where two organ-isms were isolated at the same time.
Factors associated with MDR-HAI
Comparison of clinical characteristics between the MDR-HAI and non-MDR-HAI groups found no difference in age, number of malnourished patients (body weight less than the third percentile for age), number of immunocompromised patients, number of patients referred from another PICU, exposure to invasive procedures during PICU stay, type of stress ulcer prophylaxis, mean total PICU stay, and mortality rate (Table 2). However, A. baumannii (50% vs. 23%, p = 0.04), female sex (60% vs. 29%, p = 0.02), and admission to the PICU with medical conditions (such as pneumonia, sepsis, shock, and heart failure; 90% vs. 64%, p = 0.03) were found more commonly in the MDR-HAI group when compared to the non-MDR-HAI group (Tables 1 and 2). Those who had MDR-HAI had a longer PICU stay prior to the development of HAI than those who had non-MDR-HAI (14.0 10.7 days vs. 8.6 7.9 days, p = 0.03). PICU stay longer than seven days prior to the development of HAI was found more frequently in the MDR-HAI group when compared to the non-MDR-HAI group
Table 2 Comparison of clinical characteristics between the multidrug-resistant hospital-associated infection and non-multidrug-resistant hospital-associated infection groups.
Characteristics MDR-HAI
(n = 30)
non-MDR-HAI (n = 28)
p-Value OR (95% CI)
Median age (range) 11 months (0.1—168) 4 months (0.3—117) 0.06
Female 18 (60) 8 (29) 0.02 3.7 (1.2—11.2)
Male 12 (40) 20 (71) 0.02 0.5 (0.3—0.9)
Malnourished patients 19 (63) 20 (71) 0.58 0.7 (0.2—2.1)
Immunocompromised patients 10 (33) 6 (21) 0.38 1.8 (0.6—6.0)
Referred from other PICU 9 (30) 9 (32) 1.0 0.9 (0.3—2.8)
Indication for PICU admission
Medical conditiona 27 (90) 18 (64) 0.03 5 (1.2—20.7)
Post-surgery 3 (10) 10 (36) 0.03 0.2 (0.1—0.8)
Procedures
ETT and mechanical ventilation 30 (100) 28 (100) -
-Nasogastric catheterization 28 (93) 27 (96) 1.0 0.5 (0.04—6.1)
Central venous catheterization 29 (97) 26 (93) 0.61 2.2 (0.2—26.1)
Urinary catheterization 20 (67) 20 (71) 0.78 0.8 (0.3—2.4)
Intravenous parenteral nutrition 10 (33) 8 (29) 0.78 1.2 (0.4—3.8)
Arterial catheterization 4 (13) 6 (21) 0.50 0.6 (0.1—2.3)
Stress ulcer prophylaxis
PI or H2-blocker 22 (73) 17 (61) 0.40 1.8 (0.6—5.4)
Sucralfate 7 (23) 2 (7) 0.15 3.9 (0.7—21.0)
Duration of PICU days >7 days prior to the development of HAI
20 (67) 10 (36) 0.03 1.9 (1.1—3.3)
Broad-spectrum antibiotic use within the last 2 weeks prior to the development of HAI
25 (83) 12 (43) 0.002 2.8 (1.3—6.3)
Mean (SD) total PICU days; (range) 26.2 (18.6); (3—70) 21.2 (13.5); (3—53) 0.26
Mortality rate 5 (17) 6 (21) 0.74 0.7 (0.2—2.7)
Results are n (%) unless stated otherwise.
MDR-HAI, multidrug-resistant hospital-associated infection; OR, odds ratio; CI, confidence interval; PICU, pediatric intensive care unit; ETT, endotracheal intubation; HAI, hospital-associated infection; PI, proton pump inhibitor.
(67% vs. 36%, p = 0.03). In addition, history of broad-spec-trum antibiotic use within 15 days prior to the development of HAI was found more commonly in the MDR-HAI group than the non-MDR-HAI group (83% vs. 43%, p = 0.002) (Table 2). Multiple logistic regression analysis showed that female sex (OR = 5.5, p = 0.03) and previous use of a broad-spectrum antibiotic (OR = 9.7, p = 0.01) were independent risk factors for MDR-HAI (Table 3).
Discussion
The incidence of PICU-related HAI in this study was 16.7%, equivalent to 28.3 HAI per 1000 patient-days. Fifty-two per-cent of HAI episodes were caused by MDR organisms. VAP, CR-BSI, and CR-UTI were common PICU-related HAI, while GNR and staphylococci were the commonly isolated organisms. Despite having a different PICU structure and setting when compared to those in Europe and North America, we found the same pattern of common HAI and related organisms.17—23
The most commonly isolated organism in this study was A. baumannii. Acinetobacter are ubiquitous, aerobic Gram-negative bacilli that prefer a moist environment.24Patients
who need assisted mechanical ventilation or aerosol therapy can be exposed to and colonized with this organism. In this study, A. baumannii was the most commonly isolated organ-ism among those who developed VAP. It was also the most commonly isolated organism among those who had a CR-BSI and surgical site infection during their PICU stay. Several previous studies have reported Acinetobacter as one of the predominant organisms isolated from patients in the PICU.8,9,12Colonization of the organisms in the moist
envir-onment, especially in the ventilator circuits and humidifier equipment, in addition to inadequate adherence to infection control guidelines could have led to cross-contamination between person to person and environment to person and a high incidence of Acinetobacter infection in our PICU.
In this study, 64% of isolated Acinetobacter were carba-penem-resistant. This proportion is comparable to that recently reported from a PICU in Greece, which found 62% of imipenem-resistant A. baumannii.25MDR-Acinetobacter is
an emerging worldwide problem, in both the adult and
pediatric ICU. Previous use of broad-spectrum antibiotics has been reported to be associated with the occurrence of MDR-Acinetobacter.8,26Rational use of antibiotics is neces-sary. However, surveillance of Acinetobacter colonization in the PICU and effective monitoring of adherence to the HAI control guidelines are also important. It is well documented that hand washing is the most effective strategy to prevent the development and spread of HAI. However, it is perhaps too simple and easily forgotten, especially during an emer-gency situation in the PICU. Repeat education and emphasis on the importance of HAI control for medical personnel as well as regular monitoring of adherence to the guidelines should be mandatory.
Besides a high proportion of MDR-Acinetobacter, we also found a high proportion of MDR-Pseudomonas. Fifty-eight percent of isolated Pseudomonas in our study were MDR (Table 1). All of them were imipenem-resistant. This is high when compared to rates reported in an adult ICU in Thailand and in an EPIC study, which found 31% and 21%, respectively, of isolated P. aeruginosa resistant to imipenem.4,27Prolonged
use of certain antibiotics has been reported as an important risk factor for MDR-Pseudomonas hospital-associated infec-tion.2,6Surveillance of the antimicrobial susceptibility
pat-tern and establishment of a policy for antibiotic prescription may be helpful in controlling the emergence of resistant strains.
Most of the isolated staphylococci in our study were coagulase-negative staphylococci. Only one of the isolated staphylococci was S. aureus, which was resistant to methi-cillin. Twenty-two percent of isolated coagulase-negative staphylococci were resistant to methicillin. This is relatively low when compared to rates reported in an adult ICU in Thailand and an EPIC study, which found 44% and 70%, respectively, of isolated coagulase-negative staphylococci that were resistant to methicillin,4,27 particularly as we had a high proportion of patients who had central venous catheter placement. Previous studies have reported coagu-lase-negative staphylococci as the most common pathogens related to hospital-associated bloodstream infec-tions.4,16,27,28 However, a recent study by Lakshmi et al. found that GNR, especially K. pneumoniae, were the pre-dominant organisms isolated among those who developed
Table 3 Summary of logistic regression analysis to identify independent risk factors for multidrug-resistant hospital-associated infection in the pediatric intensive care unit (all potential risk factors showing a p value of <0.2 in the univariate analysis were included in the regression model).
Variables OR 95% CI p-Value
Acinetobacter baumannii 3.9 0.9—16.7 0.07
Female 5.5 1.1—27.1 0.03
Indication for PICU admission
Medical conditiona 1.9 0.3—11.4 0.5
Post surgery 0.5 0.1—3.2 0.5
Use of sucralfate as a stress ulcer prophylaxis 8.5 0.8—91.5 0.08 Duration of PICU stay > 7 days prior to the development of HAI 1.2 0.3—4.9 0.8 Broad-spectrum antibiotic use within the last 2
weeks prior to the development of HAI
9.7 1.8—53.4 0.01
OR, odds ratio; CI, confidence interval; PICU, pediatric intensive care unit; HAI, hospital-associated infection. aMedical conditions included pneumonia, sepsis, shock, and heart failure.
primary bloodstream infections in the PICU.11In our study, we found that Acinetobacter was one of the two most commonly isolated organisms among those who had a CR-BSI. The pathogen responsible for CR-BSI can change over time and varies among ICUs. It depends not only on the use of central venous catheters, but also other factors such as type of bacterial colonization on the skin and in the ICU environ-ment, previous use of antibiotics (especially broad-spec-trum), type and severity of the patient illness, patient care procedures, and adherence to HAI control guidelines.
Several investigators have been trying to identify factors associated with MDR-HAI. Risk factors that have commonly been reported include prolonged ICU stay, frequent use of invasive devices, and severe underlying diseases.2,6—8,26,29,30 Excessive use of antibiotics has been identified as a factor associated with the emergence of MDR organisms. Some studies have reported a relationship between the use of a particular antibiotic and the occurrence of specific drug-resistant bacteria, such as piperacillin and E. coli, and third-generation cephalosporins and K. pneumoniae.6,7 In
this study, we found that previous use of a broad-spectrum antibiotic was one of the independent risk factors for MDR-HAI in the PICU. This is in agreement with results of previous studies and correlates with the high incidences of MDR-Acinetobacter and MDR-Pseudomonas in our PICU. In some studies, the initiation of antimicrobial control programs has been reported to increase bacterial antibiotic susceptibility and decrease resistant bacteria.31—34Our approach to anti-microbial prescription needs to be rationalized. An author-ization system would help in controlling the inappropriate use of broad-spectrum antibiotics. In addition, regular mon-itoring of antibiotic susceptibility patterns is also essential. Guidelines on the prevention of antimicrobial resistance should be developed and focus largely on appropriate anti-biotic prescribing.
We also found a higher proportion of females in the MDR-HAI group. This has not been reported in any previous study. However, further studies in a larger sample size and over a longer period of time are needed prior to drawing any con-clusions relating gender to susceptibility to MDR-HAI.
This study had a limitation in the identification of the etiologic agents responsible for VAP. Bronchoalveolar lavage or protected brush biopsy has been recommended as a diagnostic procedure for identifying the causative agent of VAP.16 However, there are some technical limitations with
these procedures, especially in small babies. Since most of our study patients were small (median age 6 months, 77% aged less than 5 years), we obtained the culture from endo-tracheal aspirates instead. Even though this is not the gold standard method for identifying the etiologic agent of VAP, it is non-invasive and provided some useful information regard-ing the endotracheal colonization and the selection of an antibiotic.
In conclusion, we have reported a high incidence of MDR-HAI in a PICU of a university hospital in Thailand and risk factors for these infections. Despite having a different PICU setting, we found the same pattern of common PICU-related HAI and associated organisms when compared to those reported in developed countries. However, the incidences of each isolated organism as well as the incidences of the MDR strains were different. Several factors mentioned above, as well as differences in the criteria used for the diagnosis of HAI
could have contributed to the discrepancies in the findings among the studies. Female sex and previous use of broad-spectrum antibiotics were the independent risk factors for MDR-HAI found in this study. Evaluation of the current HAI control measures as well as adherence to the hospital infec-tion control guidelines are needed. In addiinfec-tion, current use of broad-spectrum antibiotics is also an emergent issue that needs to be investigated and revised in order to decrease the incidence of MDR-HAI in the PICU.
Acknowledgements
The authors would like to thank the staff of the Department of Microbiology, Faculty of Medicine, Chulalongkorn Univer-sity for their assistance with the microbiological data, and Dr Mano Mettanando Laohavanich for his assistance in editing this manuscript.
Ethical approval: The study protocol was approved by the Ethics Committee for Human Research Study, Faculty of Medicine, Chulalongkorn University.
Conflict of interest: No conflict of interest to declare.
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