In children urinary tract infection (UTI) is commonly caused by bacteria such as E.coli, Klebsialla & enterobacter. Repeated UTI if left untreated can cause hypertension & renal failure.

Objective: To determine the frequency of common causative organisms of urinary tract infection in children with acute febrile illness.

Methods: This descriptive cross sectional study was conducted at Pathology department, King Edward Medical University, Lahore from 15th July 2019 to 15th January 2020.After ethical approval, 200 patients from 3months to 12 years of age with either gender with acute febrile illness and urinary tract infection were included. Patients with history of urinary fungal infections (Candida) & urinary tract stones, or prior antibiotics therapy were excluded. Demographic details were noted in a pre-designed proforma. A sterile technique was used to collect mid-stream urine sample. Then it was properly labeled & sent to the college pathology laboratory for culture. Urine culture was repeated if more than one organism discovered. Data for causative organism was noted on predesigned proforma. Data was analyzed by using SPSS-22.

Results: Mean age of the patients was 5.830±2.83 years, mean duration of febrile illness was 23.205±7.46 hours and mean weight was 20.675±7.27 Kg. There were 73.5% males and 26.5% females. E.coli was present in 70% patients, Enterobacter15% and Klebsiella was seen in 11% of the children.

Conclusion: Escherichia coli was the most common causative organism responsible for UTI in children of age 3 months to 12 years followed by Enterobacter and Klebsiella.

Urinary Tract Infection, Acute Febrile Illness, Causative Organism, Frequency, Children

Urinary tract infection (UTI) is the common cause of acute febrile illness in children.1 It is commonly caused by bacteria.2 There is 3%–7% incidence of UTI in girls as compared to 1 to 2% in boys3. As per World Health Organization (WHO) it is found in 24.5% children of Pakistan4. UTI is not generally reported at first level health facilities due to lack of symptoms in children, lack of diagnostic facilities & inappropriate sample collection in developing countries. Urine is sterile in the collecting system and urinary bladder however bacterial colonization is seen in urethra in healthy children. Main predisposing factors for UTI in children are urine stasis, bacterial adherence to mucosa & congenital malformations5.

Most common causative organisms for UTI in children are Bacteria & Escherichia coli is responsible for 80% of the cases6. Others include Klebsiella, Proteus, Enterobacter and Pseudomonas. In boys having kidney stones, Proteus mirabilis is a common causative organism responsible for UTI. In neonates & infants B Streptococcus and Enterococcus are responsible and in adolescent girls, Staphlococcus saprophyticus is the main culprit.7 Common contaminants of urine are Lactobacillus species, Corynebacterium, coagulase –negative staphylococci, and α hemolytic streptococci.8 untreated repeated UTI can lead to hypertension & renal failure.9

Other causes of UTI include viruses & less commonly fungi. Viruses include lower urinary tract & are adenoviruses, enteroviruses. Rare fungi causing UTI are candida & aspergillus spp.9, 10 Common predisposing factors to fungal infections are immune-compromised condition, diabetes mellitus, prolonged antibiotics use & indwelling catheter placement.11

In a study by Alizadeh Taheri P and his collegues has found that frequency of Escherichia coli was 64.4%, Enterobacter 19.2% and Klebsiella was 12.3% as causative organism of UTI in children.12 Similarly Ghorashi Z et.al concluded that Escherichia coli was 77%, Enterobacter 9% and Klebsiella was 10% as causative organism of UTI in children with acute febrile illness.13

The local pattern of urinary tract organisms is essential for selection of the appropriate empirical antibiotics for children. Therefore we conducted this study to determine the frequency of common causative organisms of urinary tract infection in children.

To determine the frequency of common causative organisms of urinary tract infection in children with acute febrile illness.

This descriptive cross sectional study was conducted at Pathology Department, King Edward Medical University, Lahore from 15th July 2019 to 15th January 2020. After ethical approval of the study, 200 cases were included through non-probability consecutive sampling with 95% confidence interval, 4% margin of error and taking expected percentage of Enterobacter as 9%.13 Patients of age 3 months to 12 years of both genders with acute febrile illness due to UTI were included. Children with history of renal stones, urinary fungal infections & current antibiotic treatment were excluded. Demographic details of patients (age, gender, weight, duration of symptoms) were recorded. Informed consent was taken from parents/guardians for this study. After disinfection of the skin of genitals, mid-stream urine samples were collected by applying an adhesive, sealed, sterile collection bag. Then the samples were properly labeled & sent to the college pathology laboratory for culture. Urine culture was repeated if more than one organism discovered. Acute febrile illness was labeled when child axillary temperature was ≥ 38°C for < 48 hours by thermometer. Urinary Tract Infection was labeled when urine culture of child showed bacterial growth (one or more of Enterobacter, E.coli and Klebsiella) of >105 colony-forming units/ml by laboratory test. All the data was recorded on especially designed proforma & was analyzed by using program SPSS-22. Qualitative variables like gender, E.coli, Enterobacter and Klebsiella were described as percentages. Quantitative variables like age, duration of symptoms (febrile illness) and weight were presented as Mean ±SD. Stratification was done with regard to age, duration of symptoms (febrile illness) and weight to see the effect of these variables on E.coli, Enterobacter and Klebsiella using the chi-square test. p ≤0.05 was taken statistically significant.

The mean age of the patients was 5.830±2.83 years. There were 73.5% males & 26.5% females. Mean duration of febrile illness was 23.21±7.46 hours and mean weight recorded was 20.68±7.27 Kg. E. coli growth was present in 70% of the patients, Enterobacter in 15% and Klebsiella were found in 11% of the patients. Other organisms were identified in only 4% of the patients.

Table- 3: Distribution of isolated organisms with respect to effect modifiers.

Our study showed that E. coli was the most prevalent (70%) causative organism of UTI in children from 3 months to 12 years of age. This finding of frequency of organisms is consistent with most of past studies.

Tebruegge M & his colleagues concluded that The commonest organisms of UTI isolated were E coli (67.4%), Enterococcus faecalis (8.4%) and Klebsiella pneumoniae (3.5%).14 In another study Chen HT et al. concluded that the most common cultured organism from urine of children was Escherichia coli same as our study.15 Mahyar A et al. in their study concluded that the most common growing organism in urine culture was E-coli (80/5%) followed by Klebsiella, Proteus, Pseudomonas, entrobacter and Staphylococcus areous.16 Taheri PA et al. in their study concluded similar frequency of organisms.17

In a study by Alizadeh Taheri P and his collegues found that frequency of Escherichia coli was 64.4%, Enterobacter19.2% and Klebsiella was 12.3% as causative organism of UTI in children with acute febrile illness.12

Similarly Ghorashi Z et.al concluded that frequency of Escherichia coli was 77%, Enterobacter 9% and Klebsiella was 10% as causative organism of UTI in children with acute febrile illness.13

Ullah A et al also found that the most prevalent uropathogenic bacteria were Escherichia coli (41.4%), Klebsiella pneumoniae (15.5%) and Proteus mirabilis (13.8%).18

Similarly Balighian E & colleagues studied urinary tract infections in children & susceptibility to antibiotics & found similar pattern of bacteria.19

In comparison to other age groups, our study of uropathogen in 3 months to 12 years was of profound significance, as UTI is hard to diagnose at this age group, no local data was already available although our study was of small sample size & single centered. Hence it will give better idea of empirical antibiotic therapy.

The most common causative organism for UTI in children from 3 months to 12 years of age is Escherichia coli followed by Enterobacter and Klebsiella. Therefore Pediatricians should use empirical antibiotics in this age group as per these results till the availability of culture results.