The recent medical developments, including the increased use of chemotherapy drugs, white blood cell stimulants, and broad spectrum antibiotics, have improved the prognosis and life span of pediatric patients with neoplastic diseases. Consequently, these patients often face lengthy periods of low immunity, undergo longer hospital stays, and there is a greater chance that they will require central venous catheterizations, urinary catheterizations, endotracheal intubations, and intravenous feeding tubes. These factors moreover put patients at an increased risk of contracting nosocomial infections (NIs) and substantially increase morbidity and mortality rates as well as treatment costs [
Nosocomial infections in patients with malignancies can be caused by bacteria, fungi, and viruses and can occur in the bloodstream; urinary, respiratory, and digestive tracts; as well as soft tissues [
In addition, the previous studies among pediatric patients with neoplastic diseases found that NIs were associated with the use of devices [
Most NIs have a significant effect since they lengthen hospital stays, increase mortality, and increase complications [
To determine (
The study was conducted in the 32-bed pediatric hematology/oncology ward of the Chiang Mai University Hospital, Chiang Mai, Thailand. Patients in this ward are up to 15 years old and all have neoplastic diseases. The patients received chemotherapy regimens based on recommendations by the Thai Pediatric Oncology Group. Antibiotic and antifungal prophylaxes are not routinely provided. We excluded those patients who (
We conducted a prospective cohort study during December 2005 and May 2006. The clinical symptoms of each patient were monitored daily from admission until hospital discharge by pediatricians and nurses. Data were obtained from medical records and nurse notes. The findings were recorded during admission on a data extraction form that included demographic data, discharge diagnoses, intrinsic risk factors, extrinsic risk factors, causal organisms, and treatment outcomes. The definitions for NIs were based on the criteria outlined by the US Centers for Disease Control and Prevention in 2004 [
The data were analyzed by calculating NI rates per 1000 days of hospitalization and per 100 admittances. The relationship between NI rates and various extrinsic factors was analyzed using a chi-square test when there was a need to compare proportional data, using a level of 95% confidence interval.
We collected data of 707 admissions (6561 days of hospitalization) during the study period (Table
Demographic characteristics of study samples.
Demographic characteristics | Number of admissions (%) ( | Number NIs (%) ( |
---|---|---|
380 (53.7) : 327 (46.3) | 27 (58.7) : 19 (41.3) | |
417 (59.0) | 19 (41.3) | |
59 (8.4) | 16 (34.8) | |
27 (3.8) | 1 (2.2) | |
11 (1.6) | 1 (2.2) | |
11 (1.6) | — | |
31 (4.4) | 1 (2.2) | |
25 (3.5) | — | |
29 (4.1) | — | |
14 (2.0) | — | |
14 (2.0) | — | |
13 (1.8) | — | |
10 (1.4) | 1 (2.2) | |
7 (1.0) | — | |
5 (0.7) | 1 (2.2) | |
34 (4.8) | 6 (13.1) |
+: Astrocytoma, Medulloblastoma, Medulloepithelioma, Ependymoma.
Nosocomial infections were reported among 46 admissions (6.5/100 admission episodes; 7 episodes/1000 days of hospitalization). There were 13 episodes of urinary tract infections per 1000 days of urinary catheterization, 21 episodes of pneumonia per 1000 days of endotrachial intubation, and no episodes of bacteremia among patients who had central venous catheterization. Episodes of NIs were most frequent among patients with ALL (41.3%), and patients with AML (34.8%).
The most common sites of NIs were the blood stream (30.5%) and the ear/nose/throat (19.6%) (Table
Types of nosocomial infections.
Types of NIs | Total Number of NIs (%) ( | Associated procedures ( |
---|---|---|
Blood stream | 14 (30.5) | ET (5), U (5), C (2) |
Ear/nose/throat | 9 (19.6) | NG (9) |
Soft tissue | 6 (13.1) | — |
Gastrointestinal tract | 6 (13.1) | NG (2) |
Urinary tract | 5 (10.9) | U (5) |
Pneumonia | 4 (8.7) | ET (4) |
Surgical site | 1 (2.2) | — |
Meningitis | 1 (2.2) | — |
ET: endotracheal intubation; U: urinary catheterization; NG: nasogastric tube; C: central venous catheterization.
Causal organisms of NIs were identified in 34 episodes (73.9%). The most common were gram-negative bacteria (47.1%), followed by gram-positive bacteria (29.4%), and fungi (14.7%) (Table
Causal organisms of nosocomial infections.
Causal organisms | Number (%) ( |
---|---|
16 (47.1) | |
3 (8.8) | |
3 (8.8) | |
3 (8.8) | |
2 (5.9) | |
5 (2.9) | |
10 (29.4) | |
5 (14.7) | |
4 (11.8) | |
1 (2.9) | |
5 (14.7) | |
3 (8.8) | |
2 (5.8) | |
3 (8.8) | |
2 (5.9) | |
1 (2.9) |
Patients who developed NIs were more likely to have had endotracheal intubation (mean duration: 10.2 days; range: 1–15 days), urinary catheterization (mean duration: 5.8 days; range: 1–10 days), nasogastric tube (mean duration: 4.9 days; range: 1–17 days), and central venous catheterization (mean duration: 1.7 days; range: 1-2 days) (
Comparison of procedures related to nosocomial infections.
Procedures | NIs (%) ( | Non-NIs (%) ( | |
---|---|---|---|
Endotracheal intubation | 9 (19.6) | 3 (0.4) | |
Urinary catheterization | 10 (21.7) | 6 (0.9) | |
Nasogastric tube | 11 (23.9) | 6 (0.9) | |
Central venous catheterization | 2 (4.3) | 0 (0) |
The mean time from admittance until time of diagnosis of an NI was 22 days (range: 2–126 days; SD: 23 days). The majority of NIs (74%) occurred between the 2nd and the 30th day of hospitalization.
Nine patients died (19.6%): 4 with ALL (44.4%), 4 with AML (44.4%), and 1 with an astrocytoma brain tumor. Four patients (44.4%) had bacteremia, 3 (33.4%) had soft tissue infections, 1 (11.1%) had pneumonia, and 1 had both bacteremia and pneumonia. Three patients (33.4%) were infected with gram-positive bacteria, 2 (22.2%) with gram-negative bacteria, 2 (22.2%) with fungal organisms, and 1 patient (11.1%) was found to be infected with gram-positive bacteria and a fungal organism.
A total of 707 admission episodes were included in the study. Forty-six episodes of NIs were reported (the incidence of NIs was 6.5/100 admission episodes; 7 episodes/1000 days of hospitalization). A previous study of pediatric patients with neoplastic diseases in Germany by Simon et al. [
In regards to sites of NIs, most infections in our study occurred in the blood stream (30.5%), as in other studies by Simon et al. [
Furthermore, our study found that fungal infections accounted for 14.7% of infections, while in the previous two studies by Simon et al. [
Concerning procedures that can make patients vulnerable to NIs, we found that endotracheal intubation, nasogastric tube insertion, urinary catheterization and central venous catheterization significantly increased the incidence of NIs (
The strengths of our study are twofold. First, it is a prospective study in which NI episodes were carefully monitored and the data collection carried out according to a given research plan. Second, according to our best knowledge, it is the first study of NI episodes among pediatric patients with neoplastic diseases in Thailand.
However, our study also has the following limitations. First, the period of data collection was relatively short. A longer period of data collection would be able to provide a clearer picture of NI episodes among this group. Second, care should be taken when comparing the incidence rates of NIs of our study with those of other institutions and countries, since we have excluded patients who had fever of unknown origin and viral related illnesses. These entities are computed in most studies as NIs per CDC criteria. Third, we also have not recorded the types of chemotherapy regimens these patients received as well as their cancer stages, which may have some impact on episodes of NIs. Further studies could address these shortcomings. Fourth, our study also did not investigate the relationship between the incidence of NIs and other intrinsic factors, including the presence of other underlying diseases as well as level of anemia and white blood cell counts.
The authors would like to thank all nurses from the Pediatric Ward of the Chiang Mai University Hospital for helping collecting data and Albert L. Oberdorfer from the English Department of the Chiang Mai University for editorial help.