Urinary Tract Infections in Children - QMHC

Urinary Tract Infections in Children Dr. Rim El-Rifai Consultant Paediatrician QMHC Outline of talk      Cases Introduction and definitions Evaluation of UTI Management Summary 7 year old girl       Initial referral to investigate secondary enuresis, had a “positive urine for UTI” Main concern nocturnal enuresis Dysuria and dark offensive urine History of PUO’s for 2 days at a time No abnormal physical findings on examination investigations  Ultrasound scan KUB:  Small capacity bladder, dilated distal ureter and urothelial thickening in Lt renal pelvis and large left kidney on USS  DMSA:  left Duplex with scarring of upper pole- has patient had MCU? 3 weeks old girl      Initial presentation to A&E: vomiting Treated with IV AB’s 2 urine samples had mixed growth but > 100 WBC on SPA FH: brother had pyloric stenosis and UTI when 4 mo old TMP ran out after 2 weeks- did not get prescription Investigations    KUB USS normal Abdo. USS: Pyloric Stenosis MCUG and DMSA awaited 6 years old girl       Referred by GP for frequency and day time wetting at school Urine showed no WBC but grew Enterococcus treated as UTI with oral TMP History: frequency and urgency but not unwell or febrile Further urine dipstick and KUB normal On questioning: urine collected in make shift jar at home What is a UTI?  An inflammatory response of urothelium to bacterial invasion that is usually associated with bacteriuria and pyuria  i.e. MSU shows:   WBC > 10 Pure growth of organisms > 107 Bacteriuria     Presence of bacteria in the urine in numbers exceeding the numbers caused by contamination from skin, urethra Not a contaminant from the skin, vagina, prepuce Collection technique sensitive May be asymptomatic Pyuria   Presence of white blood cells (WBCs) in the urine Generally indicative of an inflammation of the urothelium as a response to bacterial invasion Sites of origin of UTI  Acute pyelonephritis:  acute bacterial infection of the kidney Fever, rigors  Flank pain  Bacteriuria and pyuria   Unwell child, usually febrile Sites of origin of UTI  Bacterial Cystitis: Inflammation of the bladder     Abrupt onset of dysuria Frequency Urgency Suprapubic pain  Non-bacterial cystitis: chemical Sites of origin of UTI  Urethritis   Inflammation of the urethra Symptoms difficult to differentiate from cystitis Seen in girls with vulvovaginitis  UTI in Childhood  Features commonly non-specific  Associated with anatomical Urological abnormalities Difficulty in obtaining meaningful urine samples Tendency to cause renal scarring May lead to End Stage Renal Disease and    Hypertension in adult life UTI in Childhood   Always regarded as complicated Treatment very effective Recurrence is frequent following first UTI:   40% in females, 32% in males  Childhood UTI : Epidemiology   Prevalence is age and sex dependent Overall F > M  In 2-10% of children 2 mo – 2 yrs of age with unexplained fevers Incidence: age  UTI diagnosed in 3% of prepubertal girls, and 1% boys  In children less than 1 year:  M (2.7%) > F (0.7%) Incidence: sex     Most male infections under 3 months 10 times more common in uncircumcised males After first year 0.08% in boys 3-4% in girls until 6 years to 8% of girls are affected by UTI Up Access of bacteria  Haematogenous spread with bacteraemia in first 12 weeks  After 3 months by ascending seeding through urethra Pathogens   Most common: E. Coli Other:       Proteus spp (in boys) Klebsiella Pseudomonas Enterococcus Staphylococcus epidermidis Staphylococcus aureus Predisposing factors Most commonly       Constipation Vesico-ureteric reflux Dysfunctional voiding- poor emptying Infected periurethral area Urinary stasis: PUJ, VUJ obstruction Ureteral duplication and ectopic ureters Causes for recurrent UTI         Vesico-ureteric reflux Urinary stasis, constipation Infected periurethral area Infected atrophic kidney Ureteral duplication and ectopic ureters Infected urachal cysts, infected ureteral stump Foreign bodies Stones Vesico-Ureteric Reflux Vesico-ureteric Reflux    VUR demonstrated in 1-2% of healthy children More prevalent in infants and young children An intermittent phenomenon  Increased detection rate due to antenatal screening  Can be provoked by elevated voiding pressures Vesico-ureteric Reflux and UTI   Reported in 30-50% of children with UTI A large number still present after their first UTI  Reflux nephropathy is the cause for endstage renal failure in 3-25% of children and 10-15% of adults Evaluation of UTI Presentation/Evaluation  History in infants and toddlers:          Fever, irritability Poor weight gain (FTT) Smelly urine Abdominal Pain Dysuria, frequency, urgency Haematuria Enuresis and dysfunctional voiding Constipation, thread worm infection, sore vulva Presentation/Evaluation  History in children:         Fever Abdominal Pain (Flank/loin pain) Dysuria, frequency, urgency Haematuria “smelly urine” Enuresis and dysfunctional voiding Constipation, thread worm infection, sore vulva History/ evaluation  History in Lower urinary tract infection:        irritability Abdominal Pain Dysuria, frequency, urgency Haematuria “smelly urine” Enuresis and dysfunctional voiding Constipation, thread worm infection, sore vulva History in enuresis/ incontinence  Nocturnal symptoms:     Timing and onset of enuresis Frequency of wetting (wet nights/week) Times of wetting at night (one/several) Amount of urine passed (small/large) Urinary frequency (frequent/infrequent) Urgency and urge incontinence Quality of stream Complete emptying? Posturing (Vincent curtsey)  Daytime symptoms:      Evaluation  Physical examination: full examination including:    Growth BP genitalia   Urine test imaging Neuropathic Bladder Sacral Agenesis Laboratory assessment   Urine dipstick for Nitrites, Leukocytes Urinalysis (clean catch sample)   Direct microscopy and gram staining Culture and sensitivities AAP and RCPCH guidelines for diagnosis of UTI in infants and young children  UTI should be ruled out in infants and children assessed to be sufficiently ill to require antibiotics treatment  Diagnosis of UTI requires a culture of urine Imaging Urinary Tract Imaging       Plain Abdominal x-ray Ultrasound- any age Micturating cystourethrogram < 1 year Nuclear Imaging- any age IVU CT scan Ultrasound  Renal size and position  Scars, corticomedullary differentiation, cysts, masses, calcification, calculi    Pelvis and calyceal size and appearance  Pelvis-calyceal dilatation, urothelial thickening Dilatation, urothelial thickening, calculi outline, wall thickness, volume, residual volume Ureters  Bladder  DMSA      Renal cortical morphology Scars Overall function Differential function No information on VUR MAG 3     Quantify renal excretory function Flow imaging PUJ obstruction Indirect cystogram MCUG: Bilateral VUR DMSA: Left renal scarring Imaging of urinary tract after first febrile UTI in Young children :  USS during acute illness of limited value  MCUG useful in young age group where AB prophylaxis considered to reduce reinfection and renal scarring DMSA at presentation and 6 months later identifies renal scarring Pittsburgh SM N E J M, Jan 2003  Complications of UTI Complications    Acute:  Systemic illness, sepsis, renal abscess Renal scarring, recurrence of UTI Hypertension End-stage renal disease (overall 0.5%-5% of ESRD on dialysis have reflux nephropathy) Short term:  Long term:   Renal scarring and VUR: International Reflux Study in Children        5 yr follow up 302 patients (10 yrs in 5/8 European centres)- serial IVU and DMSA Grade III, IV, V VUR and symptomatic UTI Medical vs Surgical treatment of VUR New scars in 21 surgical and 19 medical New scars mostly in children < 5years old New scars more frequent in Grade IV New scars in 2 females > 5 years  Olbing H et al, Ped Nephrol, Oct 2003 Complications of UTI in Children  Hypertension  Pyelonephritic scarring is the most common cause for hypertension in childhood  Prevalence of hypertension independent of the degree of scarring Treatment E. Coli Resistance trends     Ampicillin 39-45% Trimethoprim-sulfamethoxazole 14-31% Nitrofurantoin 1.8-16% Fluoroquinolones (Ciprofloxacin) 0.7-10%  Mazzuli T, J Urol 2002 Drugs for Treatment       TMP 4 mg/kg BD for 7-10 days Cephalosporins (Cefuroxime, Cephalexin) Gentamicin Ciprofloxacin Ampicillin? Nitrofurantoin (over 3 mon)? Duration of treatment  Uncomplicated UTI: > 5 days is associated with higher cure rates  Tran D et al, meta-analysis of 1279 patients  J Pediatr 2001  In Children < 2years of age: 7-14 days  AAP, Pediatrics 1999 and RCPCH appraisal Drugs for prophylaxis  Trimethoprim 2 mg/kg nocte Cephalexin 12.5 mg/kg (up to 125 mg) nocte   Nitrofurantoin (over 3 mon) 1 mg/kg nocte Cessation of prophylaxis    By age 4 years When urinary continence achieved and infection free Safe in patients in whom VUR fails to resolve  Thompson et al J Urol 2001 Surgery   Anti-reflux open procedures: 95-98% success Endoscopic subureteric injections: 75-90% success     Teflon- no longer approved by FDA (success 60-84%) Collagen Macroplastique Deflux (Dextranomer/hyaluronic acid copolymer) 70% success  When?    Breakthrough UTI Persistence of VUR Parental preference Treatment: Bladder Retraining  Aims at increasing functional bladder capacity and reduction in residual volume     2-3 hourly voiding Double voiding Increasing retention capacity Isolated success in continence rate 35% Prevention Breast feeding  Lactoferrin and oligosaccharides act as analogues for microbial receptors  Prevents mucosal attachment Lactoferrin can kill bacteria, viruses and fungi  Prevention  Healthy voiding pattern      Avoidance of constipation Avoidance of local colonization Circumcision? Cranberry juice? Probiotics? Points to remember   Accurate diagnosis of UTI Low threshold to investigate in younger children (<4 years)   Appropriate treatment of acute events Consider other problems when managing UTI Points to remember The need to recognize the relationship between:  VUR  Recurrent UTI’s  Voiding dysfunction  Renal scarring   Treatment should target each factor