Fever Without A Focus

Question 1

How do you obtain a urine sample from an infant?

Answer 1

• Clean catch sample is the recommended method for urine collection. This can be very time consuming. If this is unobtainable, urine collection pads can be used but not cotton wool balls or gauze.
• When it is not possible to use non-invasive methods, a catheter sample or suprapubic aspiration (SPA) should be used. Ultrasound guidance prior to SPA is advisable to demonstrate the presence of urine.

Question 2

What is minimal change disease?

Answer 2

• Minimal change disease (MCD) is the most common form of nephrotic syndrome (a clinical condition characterised by heavy proteinuria, oedema, hypoalbuminaemia, and hyperlipidaemia) affecting children.

90% of children with nephrotic syndrome have minimal histological changes in the kidney, hence the name minimal change disease.

Question 3

What is the cause of MCD?

Answer 3

Although typically idiopathic, MCD may be secondary to certain conditions, such as Hodgkin’s lymphoma, leukaemia, and, rarely, hepatitis B or C infection. In addition, it is important to consider the role of MCD in relation to nephrotic syndrome (NS).

In MCD, no structural changes are seen in the filtration unit on light microscopy. However, with electron microscopy, effacement of the epithelial foot processes (podocytes) is seen.

Question 4

Presentation of MCD

Answer 4

• Facial or generalised oedema
• Between the ages of 2 and 8 years. MCD is uncommon in children less than 1 year of age.
• Normal BP
• Absence of haematuria
• Hx of recent viral illness

Question 5

What are the risk factors of MCD?

Answer 5

• Between the ages of 2 and 8 years.
• HL and leukaemia
• Recent viral illness.

Question 6

What are the investigations for MCD?

Answer 6

• Urinalysis
• 24 hour urine protein
• Urine protein/creatinine ratio
• Serum albumin level
• Serum lipid profile
• FBC
• GFR
• Serum LFTs
• Renal ultrasound

Question 7

What are the differentials of PCD?

Answer 7

• Acute glomerulonephritis
• Focal segmental glomerulosclerosis
• CHF
• Kwashiorkor
• Cirrhosis
• Protein-losing enteropathy

Question 8

What is the management for MCD?

Answer 8

• Corticosteroid therapy- prednisolone 60mg/BSA for 6 weeks
• Fluid restriction and low salt diet
• Albumin and furosemide

Question 9

What is the complications of MCD?

Answer 9

• Spontaneous peritonitis
• Thrombosis
• Relapse of MCD in adulthood
• Infection
• HTN

Question 10

What are congenital urogenital malformations?

Answer 10

• Kidneys begin to form 5 weeks gestation with glomeruli still forming until 34 weeks.
• Congenital anomalies of the kidney and urogenital system range from mild, asymptomatic malformations to severe, life-threatening pathologies and complex ethical dilemmas.
• Many congenital abnormalities are part of a syndrome whose impact extends beyond the urogenital system - for example, there are some congenital urological abnormalities leading to oligohydramnios and, therefore, severe pulmonary problems.

Question 11

What is renal agenesis?

Answer 11

o Virtually always unilateral (1 in 1,000 to 1 in 2,000 births).
o Renal agenesis and severe renal dysplasia are also termed hereditary renal adysplasia. The kidney is either absent or undeveloped.
o Absent kidney usually causes no symptoms and is found incidentally.
o It is thought to be an autosomal dominant trait with incomplete penetrance and variable expression.
o Ultrasound study of the kidneys of parents and siblings is recommended in all families with an affected individual.
o There is a compensatory increase in glomerular filtration in the single kidney. Theoretically this could lead to progressive damage to the remaining renal tissue
o Unilateral renal agenesis (URA) can be associated with other congenital anomalies of the kidney and urinary tract (CAKUT) and extra-renal anomalies.

Question 12

What is renal dysplasia and multi cystic kidney?

Answer 12

o Multicystic kidney of the newborn is normally seen in only one kidney as an irregularly lobulated mass of cysts and usually absent or atretic ureter.

o Frequently associated with contralateral abnormalities, especially ureteropelvic junction (UPJ) obstruction.

o 60% of kidneys affected by renal dysplasia have an obstructive component.

o Dysplasia of the renal parenchyma is seen with urethral obstruction or reflux present early in pregnancy, or obstructed ureter

Question 13

What is Potter’s syndrome?

Answer 13

o Potter’s syndrome occurs in sporadic and autosomal recessive forms with an incidence of 1 in 4,000 births.

o The name describes the typical physical appearance caused by oligohydramnios. This is classically due to bilateral renal agenesis (BRA), although it can occur with other conditions, including infantile polycystic kidney disease (IPKD), renal hypoplasia and obstructive uropathy.

o Oligohydramnios leads to pulmonary agenesis (usually with fatal outcome) and characteristic facies (folds under the eyes, flat nose, low-set ears and a receding chin).

o Bilateral renal agenesis is incompatible with life.

o In the past the condition often led to caesarean section, as it was usually associated with premature delivery, and breech presentation is a frequent finding. Prenatal ultrasound diagnosis of BRA can avoid unnecessary surgery to the mother

Question 14

What is renal hypoplasia?

Answer 14

o Most common type of congenital renal abnormality and mildest.

o There may be one small kidney with the other one larger than normal, or both may be smaller.

o Minor degrees of unilateral renal hypoplasia are common and, generally, asymptomatic.

omThe condition differs from renal dysplasia in that the kidneys are otherwise morphologically normal. There is normal residual parenchyma but smaller calyces, lobules and papillae.

o Small kidneys also have small renal arteries and are associated with hypertension requiring nephrectomy.

o Segmental renal hypoplasia, also known as the Ask-Upmark kidney, is associated with severe juvenile hypotension. It can be either congenital or the result of pyelonephritic insult in childhood

Question 15

What is supernumerary kidney?

Answer 15

o Third kidney is extremely rare and not to be confused with the relatively common unilateral duplication of the renal pelvis.

o It may be found incidentally or during investigation of other anomalies.

o Fewer than 100 cases have ever been reported - even fewer of bilateral supernumerary kidney.

o They are more commonly on the left.

o Ureteric drainage systems to the extra kidney vary but additional ureteric and genital abnormalities are typical and hydronephrosis is common

Question 16

What is infantile PKD?

Answer 16

o Severely affected foetuses are born with oligohydramnios and Potter facies; some will develop respiratory insufficiency.

o Approximately 40% have severe hepatic and renal disease, 30% have severe renal and mild hepatobiliary disease and the other 30% have severe hepatobiliary problems and mild renal disease.

o The condition is always bilateral. The hepatic manifestation is of congenital hepatic fibrosis, leading to portal hypertension.

Question 17

Is screening for PKD ethical?

Answer 17

The disease course of polycystic kidney disease in general cannot be altered therefore early detection does not have a role in childhood, when the psychological burden of chronic disease may be significant.

Due to the complexity of the disease process is it possible for a child to give adequate consent for such screening?

Question 18

What are the other types of renal abnormalities?

Answer 18

o Simple renal cyst

o Renal fusion (horseshoe) kidney- associated with trisomy 18.
-Presents with UTIs, abdominal mass and haematuria

o Ectopic kidney- kidney doesn’t ascend properly and is found in the pelvis. Ureteropelvic junction (UPJ) obstruction occurs in around 30%.
-The pelvic kidney is prone to obstruction, calculi and infection.

o Medullary sponge kidney (MSK):

• Cystic dilatation of the collecting tubules in one or both kidneys.
• Recurrent renal stones are usually seen.
• Sporadic disorder.

Question 19

What is ureteral atresia?

Answer 19

o Ureter may be absent or fail to extend to the bladder.

o Rare condition associated with multicystic kidney.

Question 20

What is the duplication of the ureter?

Answer 20

o Incomplete duplication is most often associated with ureteral reflux or UPJ obstruction of the lower pole of the kidney.

o Complete duplication is most often associated with vesicoureteral reflux, ectopic ureterocele, or ectopic ureteral insertion, all of which are more common in girls than in boys.

o It is often bilateral.

Question 21

What is ureterocele?

Answer 21

o This is a sacculation of the bladder end of the ureter that can occur either in the bladder or ectopically.

o It is much more common in girls than in boys.

o In 10% of cases it is bilateral.

o It may be asymptomatic or be associated with vesicoureteral reflux and/or obstruction of the bladder outlet

Question 22

What is prune belly syndrome?

Answer 22

o This is very rare: PBS affects 3.8 per 100,000 live male births.

o The classical triad is of urinary tract anomalies, deficient abdominal musculature, and bilateral cryptorchidism.

o There is oligohydramnios, bilateral hydronephrosis, and obstructive renal dysplasia. The bladder is greatly distended, leading to failure of the muscle layer to develop. There is undescended testis and intestinal malrotation as the distended bladder does not allow normal positioning of either.

o After drainage, the abdomen wrinkles and acquires the appearance of a prune, hence the name.

o It is associated with a broad spectrum of defects such as club foot, pulmonary hypoplasia, Potter facies, imperforate anus and arthrogryposis. Most have malformations of cardiopulmonary, gastrointestinal and orthopaedic systems.

Question 23

What is hypospadias?

Answer 23

o In hypospadias the urethral opening is not at the usual location on the head of the penis but is below it.

o In 90% of cases, the meatus is on or near the glans (distal hypospadias).

o In the remainder the meatus is near or within the scrotum (proximal hypospadias).

o In most cases the foreskin is defective on the underside of the glans.

Question 24

What is epispadias?

Answer 24

This consists of a defect of the dorsal wall of the urethra so that it ends as an opening on the upper (dorsal) side of the penis.

It is not a variant of the same process as hypospadias but a completely different embryological defect.

It can also occur in girls when the urethra develops too anteriorly.

The urethra is displaced dorsally so that it opens on to the top of the penis in males.

Females have a bifid clitoris and separation of the labia.

Question 25

What is hypogonadism?

Answer 25

o Small testes with lack of development of secondary sexual characteristics, lack of libido and potency.

o Characteristically, patients are tall with long extremities.

Question 26

What is cryptorchidism?

Answer 26

o Testicular descent is arrested.

o This is the most common congenital anomaly affecting the genitalia of newborn male infants.

o Cryptorchidism is a very common anomaly of the male genitalia, affecting 2-4% of male infants; it is more common in premature infants.

o The exact cause is uncertain.

o The most useful classification is into palpable and non-palpable testes. Clinical management is decided by the location and presence of the testes:

• Retractile testes require only observation.
• Bilateral, non-palpable testes and any suggestion of sexual differentiation problems (eg, hypospadias) require urgent, mandatory endocrinological and genetic evaluation.

o Noonan’s syndrome is a cause of this.

Question 27

What is varicocele?

Answer 27

o They develop very slowly, are unusual in boys aged under 10 years and are more frequent at the beginning of puberty. (They occur in around 14-20% of adolescents.)

o However, the cause of varicoceles may be congenital absence of valves in the left testicular vein, or the presence of anomalous branches or other abnormal variants of venous drainage.

o They appear mostly on the left side (78-93% of cases). (A unilateral right-sided varicocele is very rare and can indicate obstruction of the inferior vena cava.)

o They are caused by dilatation of the pampiniform plexus (spermatic venous plexus).

o Fertility problems arise in around 20% of adolescents with a varicocele.

Question 28

When is surgery indicated for varicocele?

Answer 28

Varicocele associated with a small testis.

Additional testicular condition affecting fertility.

Pathological sperm quality (in older adolescents).

Bilateral palpable varicocele.

Symptomatic varicocele.

Question 29

What is hydrocele?

Answer 29

Hydrocele is a collection of fluid in the scrotum, not associated with an obvious inguinal hernia.

The typical hydrocele is observed at birth as a unilateral or bilateral swelling in the scrotum, which may fluctuate in size.

It may be very tense, is usually non-tender and is, often, bluish in colour. Most hydroceles will transilluminate; a fluid- or gas-filled bowel may transilluminate too.

Most resolve spontaneously by the age of 24 months. Hydroceles that persist beyond that age are unlikely to resolve spontaneously and should, therefore, undergo elective surgical repair.

Early surgery is indicated if there is suspicion of a concomitant inguinal hernia or underlying testicular pathology.

Question 30

What is UTI in children?

Answer 30

The diagnosis of urinary tract infection (UTI) in young children is important as it may be a marker for urinary tract abnormalities.

UTI is the most common bacterial infection in children under 2 years old. UTI presents atypically in neonates and may be associated with life-threatening sepsis.

Question 31

What is lower UTI?

Answer 31

UTI involving the bladder and/or urethra

Question 32

What is upper UTI?

Answer 32

a UTI involving the renal pelvis and/or kidney (pyelonephritis).

NICE advises that clinically an upper UTI should be assumed if there is bacteriuria and fever of 38°C or higher, or if there is a fever lower than 38°C with loin pain/tenderness and bacteriuria.

Question 33

What is undifferentiated UTI?

Answer 33

a UTI where it is not possible to distinguish between the two conditions above.

Question 34

What is recurrent UTI?

Answer 34

a child has had two episodes of upper UTI, three or more episodes of lower UTI, or one episode of upper UTI and one or two episodes of lower UTI.

Question 35

What is atypical UTI?

Answer 35

NICE defines this as a UTI where there are any of the following features:
o Seriously ill/septicaemia.
o Poor urine flow.
o Presence of an abdominal or bladder mass.
o Lack of response within 48 hours to treatment with suitable antibiotics.
o An unusual causative organism (ie not Escherichia coli).
o An increased serum creatinine level.

Question 36

How many ways can you classify UTIs?

Answer 36

• Site: upper or lower as above
• Severity: simple or severe UTI, where severe UTI would include a fever of 39°C or more, the feeling of being ill, persistent vomiting and moderate or severe dehydration.
• Episode: first or recurrent.
• Symptoms: asymptomatic or symptomatic bacteriuria.
• Complicating factors: uncomplicated or complicated UTI.

Question 37

What is the classification of recurrent UTI?

Answer 37

• Recurrent UTI may be subclassified into three groups:
o Unresolved infection: subtherapeutic level of antimicrobial, non-compliance with treatment, malabsorption, resistant pathogens.
o Bacterial persistence: may be due to a nidus for persistent infection in the urinary tract. Surgical correction or medical treatment for urinary dysfunction may be needed.
o Re-infection: each episode is a new infection acquired from periurethral, perineal or rectal flora.

Question 38

What are the risk factors for UTIs?

Answer 38

• Any condition that leads to urinary stasis (renal calculi, obstructive uropathy, vesico-ureteric reflux (VUR) - or family history of, voiding disorders) or poor urine flow - eg, phimosis.
• Dysfunctional elimination syndrome.
• Sexual abuse.
• History suggestive of, or confirmed previous, UTI.
• Constipation.
• Spinal abnormalities.
• There is no associated risk factor in the majority of cases

Question 39

How does UTI present in infants younger than 3 months?

Answer 39

o Symptoms in neonates differ to those in older children. Fever, vomiting, lethargy and irritability are common.
o Poor feeding and failure to thrive may occur.
o Abdominal pain, jaundice, haematuria and offensive urine are less common.
o Neonates are more likely to develop urosepsis and infections in neonates are less likely to be due to E. coli.

Question 40

How does UTI present in infants aged 3 months or older?

Answer 40

o Fever is common.
o There may also be abdominal pain, loin tenderness, vomiting and poor feeding.
o Lethargy, irritability, haematuria, offensive urine and failure to thrive are less common.
o In verbal children, frequency and dysuria are the most common presenting symptoms.
o In preverbal children, presentation is most often a fever with no apparent cause.

Question 41

Presentation of UTI in children aged 3 or over

Answer 41

o Usual presentation is with specific symptoms such as frequency, dysuria and suprapubic, abdominal or lumbar pain.
o Dysfunctional voiding and changes to continence may occur.
o Other less common symptoms include fever, malaise, vomiting, haematuria, offensive urine and cloudy urine.

Question 42

What are the differentials of UTI?

Answer 42

• Vulvovaginitis
• Urethritis
• Irritation
• Threadworm infestation
• Balanitis
• Sexual abuse

Question 43

Which examinations are done in children presenting with UTIs?

Answer 43

The temperature of the child should always be taken and recorded.

The following should also be examined:
o Throat and cervical lymph nodes.
o Abdomen - to look for constipation, tender or palpable kidney.
o Back - to look for stigmata of spina bifida or sacral agenesis.
o Genitalia - to look for phimosis, labial adhesions, vulvitis or epididymo-orchitis.

Question 44

What are the investigations for UTIs in children?

Answer 44

• Urinalysis

• Imaging:
o Ultrasound:
-Can accurately assess renal size and outline and identify most congenital abnormalities, renal calculi and hydronephrosis or hydroureter, indicating the presence of obstruction or severe reflux.
-It is less effective in detecting mild or moderate VUR in children with UTIs.
o Micturating cystography:
-Is the gold standard investigation for reflux and is the only imaging technique that provides information about the urethra.
-Should be performed by a skilled radiologist with experience in acquiring and interpreting the images.
-The disadvantage of micturating cystography is its invasiveness, as it requires catheterisation.
o DMSA scintigraphy:
-Is the gold standard for detecting renal parenchymal defects.
-Study renal function using a radio-pharmaceutical such as technetium99m.
-The isotope is concentrated in the proximal renal tubules; its distribution correlates with functioning renal tissue.

Question 45

What is the imaging guidelines for children less than 6 months old presenting with a UTI?

Answer 45

Responds well to treatment within 48 hours:
-Ultrasound within six weeks
-Consider micturating cystourethogram (MCUG) if USS is abnormal
o Atypical UTI:
-USS during acute infection
-Then dimercaptosuccinic acid (DMSA) 4-6 months following the acute infection.
-MCUG
o Recurrent UTI:
-Same as atypical UTI

Question 46

What is the imaging guidelines for children between 6 months and 3 years old presenting with a UTI?

Answer 46

o Atypical UTI:

• USS during acute infection
• Then dimercaptosuccinic acid (DMSA) 4-6 months following the acute infection.

o Recurrent UTI:

• USS within six weeks
• DMSA

Question 47

What is the imaging guidelines for children older than 3 years old presenting with a UTI?

Answer 47

o Atypical UTI:
-USS during acute infection

o Recurrent UTI:
-USS within six weeks
-DMSA

Question 48

What is the management of UTIs in children?

Answer 48

• The aims of treatment are to:
o Eliminate symptoms and eradicate bacteriuria.
o Prevent renal scarring.
o Prevent recurrent UTIs.
o Correct any associated urological lesions.

• Children with a high risk of serious illness and/or aged younger than 3 months should be referred immediately to secondary care.
• Consider referral to secondary care for children aged 3 months and older with acute pyelonephritis or upper UTI but, if appropriate, treat with 7-10 days of oral antibiotics. If the child is unable to tolerate oral antibiotics, start treatment with intravenous (IV) antibiotics until oral intake is possible.
• Children aged 3 months and over with cystitis or infection of the lower urinary tract should be treated with three days of oral antibiotics according to local guidance.
• However, there is some evidence that outcomes of short courses (1-3 days) are inferior to those of 7- to 14-day courses