Prevalence and predictors of urinary tract infections among children with cerebral palsy in Makurdi, Nigeria ()
1. INTRODUCTION
A child with cerebral palsy has a difficulty in neuromotor control, a non-progressive brain lesion and an injury to the brain that occurred before it was fully matured [1]. Cerebral palsy is a common cause of childhood morbidity [1]. This morbidity comprised of seizure disorders, mental retardation, abnormalities of vision, problems with respiratory muscle and lower urinary tract dysfunctions [1]. The lower urinary tract dysfunctions manifest symptomatically as urinary incontinence, urgency, frequency, hesitancy and urinary tract infection [2]. Possible reasons for the propensity to urinary tract infections include vesicoureteral reflux and incomplete bladder emptying resulting from detrusor hyperreflexia and detrusor sphincter dysynergia [2-5]. In addition, the impaired cognition and the inability to communicate bladder fullness and the need to void, together with an impaired mobility may also explain the tendency to urinary retention and the attendant risk of urinary tract infections [2,6]. A prevalence of 2.2% - 32.5% of urinary tract infections among cerebral palsy patients has been reported by authors from developed countries [2,7,8]. Unfortunately, there has been no report of UTI among patients with cerebral palsy in Nigeria. This study therefore aims at determining the prevalence and predictors of UTI among cerebral palsy patients attending the Paediatric Outpatient Department of a tertiary health facility in Makurdi, Northern Nigeria. This study becomes important because of the potential complications that can result from missed and untreated urinary tract infections in children.
2. MATERIALS AND METHODS
Ethical approval for the study was obtained from the Hospital Research and Ethics Committee. Children were recruited into the study if the parents or caregivers had given their consent. Subjects were consecutive patients with cerebral palsy attending the Neurologic Clinic of the Paediatrics Outpatient Department (POD) of the Federal Medical Centre, Makurdi. Controls were age (to the nearest birthday) and sex matched consecutive children, who were also attending follow-up appointments at the POD having been previously admitted, treated and had recovered from ailments such as severe malaria, lower respiratory tract infections and diarrheal disease. Subjects and controls that had taken antibiotics in the preceding two weeks, those with on-going menses or one who is having vaginal/penile discharge were excluded from the study. Recruitment into the study spanned between December 2011 and May 2013. The clinical, topographical, gross motor dysfunctions and Intelligent Quotients characterizations of the subjects were done by the principal author. The Gross Motor Function Classification System (GMFCS) as previously described was employed to classify the severity of functional impairment in children with cerebral palsy [9]. GMFCS is a 5-level system defined by separating 4 age groups. It emphasizes sitting and walking functions of children, focusing on self-initiation of the action. Patients with GMFCS level 1 - 2 were classified as mild, those with level 3 were classified as moderate, and those with level 4 - 5 were classified as severe CP. The intellectual state of the subjects with cerebral palsy could only be tested using the Man-Drawing Quotient by Ziler that has been previously validated by Ebigbo and Izuora among Nigerian children aged 6 to 11 years [10]. Children with Intelligent Quotient ≤ 75% were considered to be intellectually disabled. A well structured pre-tested questionnaire was employed to obtain information from the parents or the caregivers of the subjects and the controlsregarding other demographic data, history suggestive of urinary tract infection, enuresis, and constipation. Symptoms of urinary tract infections captured include; fever, painful urination (dysuria; either verbally communicated to the mother of the child or mother noticed persistent crying on micturition), frequent micturition (frequency of urination of more than 7 times a day), gross haematuria, cloudy or smelly urine and flank/back pain. Constipation was as defined by The Paris Consensus on Childhood Constipation Terminology (PACCT) [11] “a period of 8 weeks with at least 2 of the following symptoms: defecation frequency less than 3 times per week, fecal incontinence frequency greater than once per week, passage of large stools that clog the toilet, palpable abdominal or rectal fecal mass, stool withholding behavior, or painful defecation”. Enuresis was defined according to the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders [12] (DSM-IV) which defines enuresis as involuntary or unintentional repeated voiding of urine, into bed or clothes, which occurs twice a week for at least 3 consecutive months, in a child that is at least 4 years old. Parents or caregivers of subjects and the control were provided with a properly labeled uncontaminated universal bottle for the collection of midstream early morning urine to be brought back when coming for their next clinic visit. The parents or the caregiver was also instructed on how to collect the mid stream urine. Routine personal hygiene is all that was required. When test cannot be done within the first hour of urine collection, urine was stored in the refrigerator (at 4˚C) and tested within 4 hours of storage in the refrigerator. Incubation of the urine was carried out on sheep blood agar, McConkey or CLED (cysteine lactose electrolyte deficient) agar using the quantitative loop method. The plates were examined at between 18 - 24 hours. A yield of multiple organisms was considered as a contaminant. Sensitivity of organisms was done using the isosensitive tested agar plate and incubated at 37˚C for 18 - 24 hours. The zones of inhibition greater than 15 mm were regarded as sensitive. A urine culture was repeated if there was a contaminant yield. Urinalysis was done using Multistix 10SG by BAYER DIAGNOSTIC and urine sediment microscopy in the standard method [13]. Urinalyses were analysed for significant proteinuria, significant haematuria, the presence of nitrite, significant pyuria and significant microscopic pyuria. Radiological investigations including abdominal ultrasound scan (USS) and micturating cystourethrogram (MCUG) were carried out among subjects and control with confirmed UTI.
For the Purpose of This Study, the Following Definitions Were Applied
Symptomatic bacteriuria (ASB) or asymptomatic urinary tract infection (AUTI) is defined as the quantitative growth of bacteria, greater than or equal to 105 colony forming units per millilitre urine of the same organism, on collected midstream urine specimens, in the absence of symptoms of urinary tract infection.
Symptomatic bacteriuria (SB) or symptomatic urinary tract infection (SUTI) is defined as the quantitative growth of bacteria, greater than or equal to 105 colony forming units per millilitre urine of the same organism, on collected midstream urine specimens, in the presence of one or more than one of these signs and or symptoms of urinary tract infection including fever, dysuria, gross haematuria, cloudy or smelly urine, frequency of urination and flank/back pain.
Significant proteinuria is a presence of 2+ or more protein in the urine.
Significant haematuria is a presence of 2+ or more blood in the urine.
Significant pyuria is a presence of 2+ or more leucocyte in the urine.
Significant microscopic pyuria is white blood cell (WBC) count of 10 and above per high power field (HPF).
3. DATA ANALYSIS
The Statistical analysis was done using SPSS version 16. Test between dependent and independent variables was carried out using the Chi-squared test (χ2). The logistic regression model was used to determine independent predictors (demographic, signs and symptoms) of urinary tract infection. Only independent variables with p value of ˂0.1 at the bivariate analysis were considered for logistic regression. Odd ratios with 95% Confidence Intervals were used to measure the strength of the association at the statistical significance level of p ˂ 0.05.
4. RESULTS
A total of 93 children with cerebral palsy were seen within the study period but only 52 were included in the study. Twenty children did not meet the inclusion criteria. Fourteen children were lost to follow-up, and they could not return the urine specimens. Mothers were unable to obtain urine specimens in 7 children. The age range was between 2 and 15 years with a mean age of 8.63 ± 3.83 years including 30 males and 22 females with a male to female ratio of 1:0.7. With respect to the types of cerebral palsy, 19 (36.5%) had spastic hemiplegia, 16 (30.8%) had spastic diplegia, 11 (21.2%) had spastic quadriplegia, 4 (7.7%) had a mixed combination of athetosis with spastic hemiplegia and another 2 (3.8%) children with hydrocephalus had ataxic cerebral palsy. Regarding the degree of gross motor dysfunction, 30 (57.7%) had mild dysfunction including 11 (21.2%) with grade I and 19 (36.5%) with grade II. Moderate to severe motor dysfunction is seen in 22 (42.3%) including eight (15.4%) with grade 3, five (9.6%) with grade 4 and nine (17.3%) with grade 5. Among the 34 children with CP whose ages were between 6 - 11 years and for which Ziler’s Man-Drawing Quotient was determined, 9 had scores ≤ 75% (i.e. Intellectually disabled) and 15 had scores above 75% (Table 1).
4.1. Urinary Symptoms/Signs, Constipation and Urinalyses Findings among Subjects with Cerebral Palsy and Controls without Cerebral Palsy
Table 2 shows that the symptoms and signs of UTI, a history of constipation, enuresis, a prior history of UTI, urinalyses findings including significant haematuria,