Paediatric Nephrology Flashcards
Urine specimen collection techniques for paeds
Paedi bag: plastic sterile bag with stick edge, only useful if NEGATIVE, if positive must collect a clean specimen
Clean catch: catching midstream, unfavourable especially in non-circumcised boys
Suprapubic aspirate - finger breadth above pubic symphysis in the midline
Catheterisation
Categories of nocturnal enuresis
Primary: has not ever established 6 months of dryness
Secondary: have at some stage established dryness, and back to wetting
Monosymptomatic: wetting at night, no symptoms during the day
Non-monosymptomatic: day time symptoms (e.g. urgency, frequency, etc. more likely to be pathologic)
The most significant factor in treatment resistance in nocturnal enuresis
ADHD
Development of bladder control in children
Most children achieve bladder control by 5y
Familial tendency to later maturation of bladder control
Exposure to stressful events may induce children with previously good bladder control to recommence bed wetting
Common associations with nocturnal enuresis
Constipation UTI Family history Sleep disordered breathing (e.g. OSA or snoring) Epilepsy ADHD Diabetes Anorexia nervosa
Assessment of enuresis
Assess frequency Daytime symptoms (urgency, wetting, UTI, frequency) Bowels ?constipation Behaviour and peer relations Previous treatments and response Perform urinalysis to exclude UTI Investigations not usually indicated
When are investigations indicated in enuresis
After failure of initial treatment or daytime symptoms
ultrasound, uroflow and residual urine
Management of enuresis
ONLY BEGIN AFTER AGED 6
- Fluid restriction at night
- Empty bladder when parents ready to go to bed
- Incentive systems (star charts)
- Enuresis alarms (body worn alarm or pad and bell)
- Desmopressin (synthetic ADH) - if alarm therapy failed or contraindicated (ADHD) - melts are preferred, nasal spray associated with hypoNa
- Anticholinergics - Oxybutinin (if resistant to desmopressin, may use in combination if neither monotherapy is effective)
Conditions predisposing children to UTIs
Vesico-ureteric reflux Urinary obstruction (e.g. calculi secondary to cystinuria)
Common pathogens for paediatric UTIs
E Coli Proteus Klebsiella Enterococcus Staphylococcus
Management of UTI in a child
In well child: Oral Abx 5 days (10-14 if pyelonephritis present)
IV Abx if systemically unwell, vomiting oral medication or infant less than 6m
Prophylactic Abx if awaiting imaging results in a young child under 2
Definition of vesicoureteric reflux
Urine passing in a retrograde direction from the bladder through the vesico-ureteric junction into the ureter
Epidemiology of VUR
40% kids under 1y who are investigated for a first UTI have some degree of reflux (usually grade I or II)
Family trait affecting 30-50% of first-degree relatives of index cases
Higher grades are associated with higher recurrence rates of UTI +/- renal scars
Follow-up of UTI in infants
USS
MCU (micturating cysto-urethrogram) - indicated if normal USS or no obstruction on MAG3, will show VUR if present
DMSA (dimercaptosuccinic acid) “scars” - radionucleotide study, indicated 1-2 years after last UTI, reduced uptake of dye indicates scarring of kidney
DTPA (diethylene tramine penta-acetic acid) GRF
MAG3 (mercapto acetyl triglycine +/- captopril) - indicated if dilation of urinary tract, hydronephrosis or hydroureter on USS
Diagnosis of VUR
made by micturating cystourethrogram or by DMSA (radionucleotide study showing scarring of kidneys if reduced uptake)