Renal Conditions

Vesicoureteral reflux

This is the backflow of urine from the bladder into the ureter, which is divided into 2 types.

– The backflow of urine predisposes children to recurrent infections which can later lead to renal scarring.

– If left untreated, it is a risk factor for later developing progressive chronic kidney disease and hypertension

Primary VUR

This is the most common type, which occurs due to a congenital defect in the vesicoureteral junction

– This defect causes the ureters to enter the bladder in a more perpendicular fashion

– This reduces the length of the ureter in the wall of the bladder meaning that the vesicoureteral junction cannot function adequately.

– This means that urine can flow backwards in the ureter leading to complications

– This usually resolves with age

Secondary VUR

This where the cause of backflow is due to some point in the urinary tract other than the VUJ:

– This includes causes such as urethral obstruction, UTI causing inflammation of the urinary tract or a neuropathic bladder

Symptoms:

– Presents as multiple recurrent UTIs at a young age

– This gives abdominal pain, dysuria and frequency

Diagnosis:

Micturating cystourethrogram shows urine backflow into ureters

– Grade I –> Reflux into ureter only without dilatation of ureter

– Grade II –> Reflux into renal pelvis, no dilatation

– Grade III –> Mild dilatation of urinary tissue

– Grade IV –> Dilation of the kidney with some tortuosity of ureter

– Grade V –> Severe dilation with ureteral tortuosity

Management:

– 1st line is conservative –> fluid intake, regular voiding, complete bladder emptying, avoid constipation

– 2nd line is medical –> antibiotic prophylaxis (trimethoprim)

– 3rd line is surgical approaches to repair the VUJ

Wilm’s tumour (Nephroblastoma)

This is a malignant kidney tumour of the young renal tubules and kidney cells – it is the most common abdominal malignancy in children, presenting usually around the age of 3.

– Classic Wilms tumour gives a 3-component appearance in histology –> stromal, epithelia and blastemal

– In children <1, this is called a metanephric blastema

Causes:

Most cases are sporadic, but it is also associated with hereditary disorders:

Symptoms:

– Similar to adults (Triad of painless haematuria, loin mass and lumbar pain)

– Weight loss/failure to thrive + enlarged kidneys

Management:

Nephrectomy to remove the affected kidney

Potter’s sequence

This is a complication which occurs due to severe oligohydramnios in the uterus which affects foetal development

– This usually occurs due to problems with the fetus’ kidneys, which reduces foetal urine production

– This reduces the level of amniotic fluid in the uterus, reducing the space in the amniotic sac

– The lack of cushioning fluid results in foetal compression giving deformities

– This amniotic fluid urine is also essential for foetal lung development. Without urine production, it leads to underdeveloped lungs, leading to respiratory failure shortly after birth

Causes:

Bilateral renal agenesis, Bilateral MCDK, obstructive uropathy

Symptoms:

– Lung deformities –> Pulmonary hypoplasia giving respiratory failure

– Facial deformities –> low-set ears, parrot beak nose, prominent epicanthic folds

– Organ deformities –> anal atresia, absence of rectum/colon, diaphragmatic hernia

– Limb deformities –> clubbed feet

Management:

Very difficult to treat. Baby is usually stillborn or will die soon due to respiratory failure

Enuresis

This is the involuntary discharge of urine in a child older than the age of 5 years

– Whilst it is common, less than 10% of the bedwetting cases have a pathological medical cause, and most of the time children grow out of this pattern of behaviour with training as they get older

– Primary enuresis is for cases where the child never achieved continence, whereas secondary enuresis is used in cases where the child had achieved continence for at least 6 months

Primary enuresis

This is the involuntary of discharge of urine in a child who never achieved continence.

– This is divided into two types, nocturnal enuresis, or enuresis at night with daytime symptoms

i) Primary Nocturnal Enuresis:

Commonly, referred to as bedwetting, the child is dry during the day but involuntarily passes urine during sleep.

– This is most likely to be due to behavioural, such as the child not using the toilet before bed. However, it can be due to biological causes too.

Causes:

– Behavioural –> drinking water before bed, not emptying bladder before bed

– Sleep arousal difficulties –> inability to wake to noise or sensation of a full bladder

– Bladder dysfunction -> small capacity or overactive bladder

Symptoms:

– Presents as bedwetting at night

Management:

– Reward systems (star charts) – given for good behaviour like using toilet before bed to train good habits

– 1st line is enuresis alarm. This senses moisture in the nappy and will wake the child up if moisture detected

– if unresolving, then can try desmopressin (ADH analogue) which reduces urine production

– If persistent after 2 treatment courses –> refer to enuresis clinic for specialist input

ii) Primary enuresis with daytime symptoms

– This is the involuntary of discharge of urine in a child during the night and daytime

– It is usually due to disorders of the lower urinary tract which require further investigation

Causes:

– Overactive bladder, structural abnormalities

– Neurological disorders (e.g., neurogenic bladder due to spinal dysraphism)

Symptoms:

Bedwetting at night and daytime wetting, urgency, frequency, dysuria

– If neuropathic bladder –> gives distended bladder, spinal malformations, neurological symptoms

– If ectopic ureter –> constant dribbling, child always damp

– Increases risk of UTI –> dysuria, frequency, urgency

Tests:

Urinalysis to rule out UTI

Management:

Refer to specialist for further investigation

Secondary Enuresis

This is the involuntary passing of urine in children >5 who had achieved continence before for 6 months

– This is more likely to be due to an acute problem, such as UTI or a change in the family situation

Causes:

– Medical –> Diabetes, UTI,

– Behavioural –> family problems, psychological problems

Tests:

– Urinalysis to check for infection

Management:

– Manage the underlying cause

Urinary Tract infection

This is a general term which describes a bacterial infection anywhere of the urinary tract.

– UTI is more common in boys until 3 months age (due to congenital problems) but then become more prevalent in girls above this age.

– A recurrent UTI is having 3 or more episodes of lower UTI or 2 or more of upper UTI

– Like adults, the most common causative organism is E. Coli

Risk Factors:

– Vesicoureteral reflux –> this is the most common abnormality in children with recurrent UTI

– Female –> they have a less vertical urethra making bacterial travel easier. In addition, poor wiping technique (not wiping from front to back) may exacerbate this further

– Decreased urine flow –> due to incomplete emptying, neuropathic bladder or obstructions within the urinary tract

– Higher bacterial growth –> due to type I diabetes

Management:

– If age < 3 months –> refer paediatrician

– If > 3months with upper UTI –> give cephalosporin/co-amoxiclav for 7-10 days

– If > 3months with lower UTI –> give cephalosporin/amoxicillin/trimethoprim/nitrofurantoin for 3 days