Urogenital disorders Flashcards
What is renal agenesis?
- Failure to develop one or both kidneys
- Unilateral renal agenesis affects 1/750 live births worldwide
- Bilateral renal agenesis affects 1.5/10,000 foetuses and many do not survive to birth
What are the clinical features of renal agenesis?
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Bilateral: no urine is produced in the womb so there is an abnormally low amount of amniotic fluid = oligohydramnios
- Consequently lung hypoplasia occurs and babies are born with the oligohydramnios sequence/ Potter’s sequence
- Potter’s sequence = a consequence of any pathology causing severe oligohydramnios. Clubbed feet, cranial abnormalities and pulmonary hypoplasia. Because the foetus does not have the protection of amniotic fluid it is compressed, amniotic fluid is also essential for lung development in the foetus because it allows for airway expansion and provides the amino acid proline which is needed for lung development
- Unilateral renal agenesis is usually asymptomatic
How is renal agenesis managed?
- Bilateral - very poor prognosis, increased risk of intrauterine death and babies that are born usually die after birth due to respiratory insufficiency
- Unilateral - no management required
Multi-cystic dysplastic kidney
Non functioning kidney full of cysts
- Usually unilateral
- Occurs in 1 in 2500
- Not hereditary but cause is unclear
Clinical features of multi-cystic dysplastic kidney
- Usually detected antenatally via USS
- Abdominal mass may be felt in the neonate
- Usually no other symptoms
How is multi-cystic dysplastic kidney managed?
- Mainly monitoring of the healthy kidney using USS
- Abnormal kidney usually shrinks by the age of 10 but if it doesn’t there is a risk of malignancy so some patients choose to have the kidney removed
- Prognosis is good but the normal kidney is at risk of vesicoureteric reflux (flow of urine back into kidney) and requires monitoring because health of the remaining kidney is essential
- Bilateral multi-cystic dysplastic kidney is not compatible with life
What is duplex kidney?
Anatomical variation where the pelvicalyceal and ureteric systems are doubled
Affects 1 in 750
What are the clinical features of a duplex kidney?
- Many are asymptomatic
- Can cause recurrent UTI because the duplicated ureter is prone to hydronephrosis and reflux.
- Condition is identified on USS
Management of duplex kidney
- If asymptomatic - no management is needed
- If recurrent UTIs monitoring and prophylactic antibiotics
What is hydronephrosis?
Dilation of the renal collecting system due to a blockage - the site of the blockage determines whether it is unilateral or bilateral hydronephrosis
Clinical features of hydronephrosis
- Usually asymptomatic
- Identified on antenatal USS
- Cause of the dilation is determined by either micturating cystourethrography for urinary reflux or a radio-isotope scan for ureteric blockage
Management of hydronephrosis
- Depends on the cause and the damage
- Obstruction rarely requires intervention as the narrowing tends to resolve as children grow
What are posterior urethral valves?
Congenital abnormality in which a membrane develops in the posterior neck of the urethra in the prostatic region - this obstructs urine flow from the bladder
- Most common cause of bladder obstruction in male babies - affects 1/8000 live births
- Females are not affected
- Cause not known - it is thought that development of the male urethra is disrupted during weeks 9-14 as the Wolffian duct integrates abnormally
Section of urethra affected is that nearest to the bladder
- Referred to a congenital obstructive condition
Clinical features of posterior urethral valves
- Obstruction of the flow of urine results in:
- Dribbling of urine and poor urine stream
- Enlarged bladder with a thickened wall causing the wall to become less compliant
- Bilateral hydronephrosis as the urine has nowhere to go but backwards
- Recurrent UTI due to urine stagnation
- If the obstruction is severe it can cause oligohydramnios and Potter’s sequence
If baby boys are found to have bilateral hydronephrosis this raises suspicion of posterior urethral valves
How are is posterior urethral valves diagnosed?
- USS, micturating cystourethrography and cystoscopy
Management of posterior urethral valves
- Catheter inserted to allow urine to drain and then the valve is surgically ablated
What is vesicoureteric reflux?
The backwards flow of urine resulting in dilation of the renal tract
- Affects 1/100 with girls more commonly affected than boys
- Frequently familial
- Occurs due to anatomical abnormalities at the vesicoureteric junction or secondary to conditions leading to bladder obstruction e.g. posterior urethral valves
- Can be unilateral or bilateral
Clinical features of vesicoureteric reflux
- Either detected following investigations for hydronephrosis or following a UTI in an infant or toddler
- Reflux causes recurrent UTIs or pyelonephritis because the urine stagnates
- Recurrent infections can cause scarring of the kidney
Diagnosis of vesicoureteric reflux
- Suspected if hydronephrosis is seen or recurrent UTIs occur with unusual organisms
- Diagnosis confirmed using micturating cystourethrography in which contrast inserted in the bladder is shown to travel up the ureters into the kidneys
Management of vesicoureteric reflux
- Depends on severity
- Prophylactic antibiotics to prevent infection in a bid to reduce damage to the kidneys
- Most children grow out of it
- If the problem persists surgery may be required to prevent serious scarring to the kidneys
What is hypospadias?
Congenital condition in which the opening of the urethra is not in its usual position at the tip of the penis
- Occurs due to abnormal fusion of the urethral folds
- 1/300 males are affected so it is fairly common
- Openings occur along the ventral/ underside of the penis
- 80% are mild with the opening still being located in the glans of the penis
- Moderate hypospadias occur when the opening is in the shaft of the penis
- In severe cases the opening is in the scrotum or perineum
- There may be an associated downward curvature of the penis
- Surgical correction is often required - the foreskin is often needed for surgery so babies with this condition should not be circumcised
What is the most common UTI-causing organism?
E.coli
Clinical features of UTIs in children
- Depend on the age of the child and which part of the tract is affected
- Babies: symptoms are non-specific so a UTI has to be actively excluded in any baby who is unwell or has a fever
- Verbal children >4yrs: dysuria, frequency, loin/ abdo pain, incontinence fever, vomiting
Diagnosing a UTI in a child
- Ideally a clean catch urine sample will be obtained but this is rather tricky
- Children over the age of 3 - diagnostic test is urine dipstick showing nitrates and leucocyte esterase
- If UTIs are recurrent a culture sample is also sent to ensure effective antibiotics are being used
- In babies and children <3yrs urinalysis results are unreliable so diagnosis depends on microscopy and culture
Management of UTI in children
- infants less than 3 months old should be referred immediately to a paediatrician
- IV antibiotics for any child who is systemically unwell or if they are <3 months
- All other children are treated with a course of oral antibiotics e.g. trimethoprim or co-amoxiclav with the treatment duration depending on the location of the infection (upper = 7-10 days, lower = 3 days)
- For recurrent UTIs look at the previous culture results to guide antibiotic therapy
Epidemiology of UTIs in children
Urinary tract infections (UTI) are more common in boys until 3 months of age (due to more congenital abnormalities) after which the incidence is substantially higher in girls. At least 8% of girls and 2% of boys will have a UTI in childhood
What is noctural enuresis?
Bed wetting - involuntary voiding of urine while sleeping
Primary vs secondary enuresis
Primary nocturnal enuresis: child has never been consistently dry for a period of 6 months
Secondary nocturnal enuresis: child has previously been dry for at least 6 months
Epidemiology of enuresis
- Common
- 2.6% of 7 year olds wet the bed on 2 or more nights per week
- Boys affected more than girls
Causes of enuresis
- Usually a combination of genetics, delayed maturation of bladder control and small bladder capacity
- Low levels of vasopressin is a factor in some as it causes overproduction of urine at night
- If secondary, it is often due to emotional issues or a UTI
Associated features with enuresis
- Most children will have totally normal development
- 20% have associated symptoms of bladder dysfunction
- Constipation can also cause problems because it causes pressure on the bladder
Diagnosis of enuresis
- Usually clinical based on hx and examination
Hx:
- Frequency and pattern of bed-wetting
- Any daytime symptoms
- Associated symptoms e.g. constipation
- Childs drinking and toileting habits
Management of enuresis
- Mostly simple behavioural advice
- Encourage child to drink enough during the day and use the toilet regularly
- Limit the amount of fluid consumed immediately before bed and remind child to use the toilet before bed
- If the child is >5 years and had tried and failed to stop bed wetting, a bed-wetting alarm system can be used that is set off if the child starts to wee
- If the alarm system is unsuccessful desmopressin (synthetic form of ADH), which causes the kidneys to retain more water **important that children don’t drink 1hr before and 8hrs after taking desmopressin because it can lead to fluid overload
- By 10 years of age 95% of children are dry at night
What are the features of nephrotic syndrome?
- Proteinuria
- Hypoalbuminemia
- Oedema
Caused by leakage of protein from the glomeruli into the urine
*hyperlipidaemia can also occur
Epidemiology of nephrotic syndrome in children
Affects 1/50,000 children, usually between the age of 2-6. More common in Asian children
- Most cases are idiopathic but can rarely occur due to secondary illness such as lupus or henoch schonlein purpura
Histological classification of nephrotic syndrome
- Minimal change disease (80% of cases) no glomerular inflammation and no changes are seen on normal light microscopy but electron microscopy shows effacement of the podocytes
- Focal segmental glomerulosclerosis (10%) sclerosis of the podocytes in some of the glomeruli. Defined genetic cause in 25% of cases
- Membranoproliferative glomerulonephritis (6%) inflammation and proliferation of glomerular basement membrane and mesangium due to immune complex deposition or abnormalities of the alternative complement pathway
Clinical features of nephrotic disease
- In children the most common presenting feature is periorbital oedema
- As the disease progresses the oedema becomes more generalised, with scrotal swelling in boys
- Ascites and pleural effusion can occur
- Some children present in shock due to low intravascular volume because of lack of protein
Diagnosis of nephrotic syndrome
- Dipstick: + for protein and high early morning protein:creatinine ratio
- Bloods: low levels of albumin and hyperlipidaemia
- Minimal change disease is the most common cause in children so a biopsy is only needed if the child is <1 or >8, has hypertension, gross haematuria or has proteinuria >4weeks after starting steroids
Management of nephrotic syndrome
- Treated with steroids which induce remission in most children but many of these relapse within 2 years of the start of treatment, especially when unwell e.g. with a cold
- Children with steroid dependant nephrotic syndrome, meaning as soon as their steroids are reduced or stopped they relapse, may need treatment with other immunosuppressants
- Low salt diet and fluid restriction to minimise fluid retention
Prognosis of nephrotic syndrome
- Minimal change disease carries a good prognosis and most children stop having relapses by adulthood
- 30% of membranous nephropathy progresses to end stage renal failure
Henoch-Schönlein purpura
Vasculitis that causes inflammation of small blood vessels in several body systems
- Most common vasculitic disease in children
- Affects 10-20/100,000 children aged 2-11yrs
- Boys affected more than girls
- Thought to occur via an immune mediated process triggered usually by an upper resp. tract infection
Clinical features of Henoch-Schönlein purpura
- The inflamed blood vessels allow blood to leak into the tissues and cause a palpable purpuric rash - this occurs mainly on the legs and bum
- Joint pain and swelling
- Abdo pain
Diagnosis of Henoch-Schönlein purpura
- Clinical, based on rash and other symptoms
- FBC and coagulation tests carried out to rule out other causes of purpura such as thrombocytopenia
- Urinalysis and kidney function tests to rule out renal impairment
Management of Henoch-Schönlein purpura
- Supportive, analgesia for joint pain and monitoring of BP
- Most children recover without problems but 1% end up with ESRD
Types of renal failure
Acute kidney injury: sudden decline in renal function leading to retention of waste products, impairment may be reversible
Chronic kidney disease: irreversible injury leading to persistently reduced renal function
Causes of AKI in children
Pre-renal AKI in children:
- Hypovolemia due to vomiting or diarrhoea or burns
- Heart failure
- Renal artery stenosis
- Use of drugs accidentally e.g. NSAIDs. ACEis
Renal AKI in children:
- Haemolytic uraemic syndrome
- Glomerulonephritis
- Use or overdose of drugs
- Autoimmune disease e.g. lupus
Post-renal AKI in children
- Posterior urethral valves
- Renal stones
- Blocked catheter
Causes of CKD in children
CKD is uncommon in children, normally caused by congenital or structural problems with the kidneys
Most common causes:
- Hypoplastic or dysplastic kidneys
- Reflux nephropathy
- Obstructive uropathy
- FSG
- PCKD
Clinical features of CKD
- Asymptomatic in early stages
- As it advances causes lethargy, anorexia, nausea and vomiting
- Hypertension, poor growth, anaemia and metabolic disturbances
Management of CKD in children
- Regular monitoring and preservation of existing renal function
- Avoid nephrotoxic drugs
- Control blood pressure
- Dialysis or kidney transplant needed if GFR decreases to <15
Haemolytic uraemic syndrome
Triad of:
- Haemolysis causing anaemia and jaundice
- AKI causing increased urea levels
- Low platelets
Affects 1/10,000 children, mainly Caucasian under 5yrs
- Typically occurs secondary to exposure to a shiga-like toxin produced by E.coli O157 which is most commonly acquired following consumption of contaminated meat.
- The toxin binds to receptors on glomeruli endothelial cells which causes small clots in the blood vessels, platelet activation, widespread inflammation and red blood cell breakdown
- 5% of cases are not related to shiga-like toxin exposure
Clinical features of haemolytic uraemic syndrome
- Recent hx of vomiting and diarrhoea which is often bloody, 3-7 days before the onset of the syndrome
- Child is usually unwell, pale or jaundiced with a reduced urine output
- A minority have neurological symptoms
Diagnosis of haemolytic uraemic syndrome
- FBC shows anaemia and thrombocytopenia
- Evidence of haemolysis on blood film
- Renal function impaired with features of acute renal failure in 70%
- Microbiology of stool will confirm presence of E.coli O157
Management of haemolytic uraemic syndrome
- Supportive, includes correction of fluid and electrolyte imbalances
- Dialysis/ blood transfusion may be needed to manage acute renal failure and haemolytic anaemia
- 70-85% make a full recovery but regular follow up to monitor renal function is essential
- Mortality is 5-15%
- Those with non-Shiga disease fair worse, 25% die during the acute phase and 50% will have ESRD
Most common type of hernia in children
- In children the most common type is an inguinal hernia which results from protrusion of the intestine through the abdominal wall via the inguinal canal
- Present in 3% of newborns
- M:F 9:1
- Incidence increases with increasing prematurity
Clinical features of hernias
- Painless swelling in the inguinal region or scrotum
- Incarcerated hernia (one that is stuck) presents as a painful, firm and irreducible mass
- Symptoms of obstruction such as vomiting and distension are also present
Diagnosis of hernias
- Usually made on clinical examination but may be confirmed using USS
Management of hernias in children
- Inguinal herniae in babies are at high risk of incarceration so surgical repair is essential
- Incarcerated herniae require urgent surgical reduction to avoid ischaemia of its contents
What is a hydrocele?
- Collection of peritoneal fluid in the scrotum
- Fluid enters via a patent processus vaginalis which allows communication between peritoneum and scrotum
- Present in 5% of newborn boys
Clinical features and diagnosis of hydrocele
- Appears as a painless fluctuating scrotal swelling
- Vary in size
- Can be unilateral or bilateral
- Diagnosis by clinical examination with transillumination helping to differentiate between a hydrocele and a hernia - hydrocele will transilluminate (shine red) but hernia will not
Management of hydrocele
- Most resolve within a few months of birth
- If it persists beyond 2yrs surgical repair is needed
Cryptorchidism
When one or both testes are not palpable in the scrotum usually due to failure of descent of the testes in utero which occurs in the third trimester
- Common finding with 3-5% of term boys being affected
- Incidence much higher in prem babies because they are born before the time the testes would descend
Cryptorchidism clinical features
- Diagnosis made following routine newborn examination
- Testicle is usually palpable in the inguinal canal or shown on USS to be in the abdomen
Management of cryptochordism
- Testes usually descend spontaneously so if they are palpable then nothing is done at first
- Increased risk of testicular torsion and reduced fertility if not descended by 1yr of age so an orchidopexy/ surgical repositioning of the testes in the scrotum is carried out
- If testes cannot be repositioned are removed because of risk of malignancy
Testicular torsion
- Twisting of testicle at spermatic cord which reduces blood flow to testes and can cause ischaemia
- Affects 1 in 4000 males under 25yrs
- Peak incidence around puberty
Clinical features and diagnosis of testicular torsion
- Sudden onset of pain in affected testicle
- Swelling, erythema and tenderness on examination
- Absence of cremasteric reflex (balls should raise when leg is stroked)
- Urgent doppler used to confirm diagnosis - showing absence of blood flow in testes
Management of testicular torsion
- Surgical emergency
- Surgery must be carried out within 6hrs of symptom onset to prevent necrosis
- Surgeons untwist spermatic cord and if the testicle appears viable an orchidopexy is done
- Good prognosis if surgery done and blood flow restored
- Orchidopexy is usually carried out on other testicle to fix it in place because there is risk the other testicle will twist
Epididymitis and orchitis in children
- Rare in prepubertal children but more common in older boys
- Can be associated with STIs in adolescents esp. chlamydia and gonorrhoea
- Mumps is a common cause in all ages
Clinical features
- Acute pain and swelling of scrotum
- Urinary frequency
- Penile discharge and blood in semen
Diagnosis and management of epididymitis/ orchitis
Diagnosis:
- Dipstick analysis and culture to rule of UTI
- Penile swabs if STI suspected
- Doppler shows increased blood flow
Management
- UTI or STI is treated with antibiotics
- Good prognosis
Phimosis and balanitis
Prepuce/ foreskin is closely adhered to the glans penis for the first year before it separates
Balanitis = swollen, sore head of penis
Phimosis = inability to retract foreskin
Common medical indications for circumcision
- Tight phimosis
- Recurrent balanitis i.e. inflammation or infection of the glans penis and prepuce
Circumcision for medical reasons is rarely done for children under 3yrs
- Complications occur in 5%
- Most common immediate complications are pain and bleeding
- Later complication is meatal stenosis
Managment of phimosis
The British Association of Paediatric Urologists states that if the issue is a non-retractile foreskin and/or ballooning during micturition in a child under two, an expectant approach should be taken in case this is physiological phimosis which will resolve in time. Forcible retraction can result in scar formation so should be avoided. Personal hygiene is important. If the child is over 2 years of age and has recurrent balanoposthitis or urinary tract infection then treatment can be considered
Causes of balanitis
Most common causes are infective (both bacterial and candidal) although there are a number of other autoimmune causes
Infective: candidiasis (very common), bacteria
Contact dermatitis
Dermatits - eczema/ psoriasis
Investigations for balanitis
- The majority of conditions are diagnosed clinically based on the history and physical appearance of the glans penis.
- In the cases of suspected infective causes a swab can be taken for microscopy and culture which may demonstrate bacteria or Candida albicans.
- When there is a doubt about the cause and there is extensive skin change, then a biopsy can be helpful in confirming the diagnosis.
Management of balanitis
General treatment:
Gentle saline washes, ensuring to wash properly under the foreskin, and in the case of more severe irritation and discomfort then 1% hydrocortisone can be used for a short period.
When the cause is not clear, these measures can often resolve the condition alone.
Specific treatment:
- In the case of candidiasis the treatment is with topical clotrimazole which has to be applied for two weeks to fully treat the infection.
- Bacterial balanitis is most often due to Staphylococcus spp. or Group B Streptococcus spp. and can be treated with oral flucloxacillin or clarithromycin if penicillin allergic.
- Anaerobic balanitis is managed with saline washing and can also be managed with topical or oral metronidazole if not settling.
- Dermatitis and circinate balanitis are managed with mild potency topical corticosteroids (e.g. hydrocortisone)
- Lichen sclerosus and plasma cell balanitis of Zoon are managed with high potency topical steroids (e.g. clobetasol).
- Circumcision can help in the case of lichen sclerosus.
