Nephrology

Question 1

What are the causes of acute nephritis?

Answer 1

o Post-infectious- including streptococcus
o Vasculitis
 Henoch–Schönlein purpura
 SLE
 Wegener granulomatosis
 Microscopic polyarteritis
 Polyarteritis nodosa
o IgA nephropathy and mesangiocapillary glomerulonephritis
o Anti-glomerular basement membrane disease (Goodpasture syndrome)- very rare

Question 2

What are the clinical features of acute nephritis?

Answer 2

o Decreased urine output and volume overload- oliguria
o Hypertension- which may cause seizures
o Oedema- characteristically around the eyes
o Haematuria & proteinuria

Question 3

What is the management for acute nephritis?

Answer 3

both water and electrolyte balance and the use of diuretics when necessary
renal biopsy and subsequent treatment with immunosuppression and plasma exchange may be necessary
prognosis worse if acute presentation of chronic nephritis

Question 4

What are the symptoms of HSP?

Answer 4

o Characteristic rash- buttocks, extensor surfaces of legs & arms and ankles
o Arthralgia- joint pain – knees and ankles
o Periarticular oedema- joint swelling – knees and ankles
o Abdominal pain- haematemesis & melaena and intussuception
o Glomerulonephritis- microscopic/macroscopic haematuria (80%) and nephrotic syndrome (rare)

Question 5

What are the features of HSP?

Answer 5

3-10yrs, twice as common in boys, peaks during winter months, preceded by a URTI
Rash is characteristically palpable and may recur over several weeks- it is the first clinical feature in about 50% and is the cornerstone of the diagnosis

Question 6

What are the complications of HSP?

Answer 6

GI petechiae can cause haematemesis and melaena- intussusception can occur and can be particularly difficult to diagnose under these circumstances
ileus, protein-losing enteropathy, orchitis and occasionally CNS involvement are rare complications

Question 7

What are the risk factors for long term complications in HSP?

Answer 7

• If proteinuria is more severe then nephrotic syndrome may result
o Heavy proteinuria
o Oedema
o Hypertension
o Deteriorating renal function
• All children with renal involvement will be followed for a year to detect those with persisting urinary abnormalities

Question 8

What is post-streptococcal and post infectious nephritis?

Answer 8

• Usually follows a streptococcal sore throat or skin infection- is diagnosed by evidence of a recent streptococcal infection (organism culture, raised ASO/anti-DNAse B titres) and low complement C3 levels, that return to normal after 3-4 weeks
Long term prognosis is good

Question 9

What is familial nephritis?

Answer 9

Commonest familial nephritis is Alport syndrome
X-linked recessive disorder that progresses to end-stage renal failure by early adult life in males
• It is associated with nerve deafness and ocular defects
• The mother may have haematuria

Question 10

What are the characteristic symptoms of vasculitis?

Answer 10

o Fever
o Malaise
o Weight loss
o Skin rash
o Arthropathy
prominent involvement of the respiratory tract in Wegener disease
• ANCA (anti-neutrophil cytoplasm antibodies) are present and diagnostic in these diseases

Question 11

What is the treatment for vasculitis?

Answer 11

steroids, plasma exchange and IV cyclophosphamide, which may need to be continued for many months

Question 12

What are the investigations for SLE?

Answer 12

o	Electrolytes and creatinine- to assess renal function
o	FBC- infection, anaemia
o	Urinalysis- infection, protein, blood
o	Urine culture- infection
o	Complement levels
o	ASO titre
o	Anti-DNAase B
o	Serum IgA measurement

Question 13

What is nephrotic syndrome?

Answer 13

heavy proteinuria results in a low plasma albumin and oedema
Sometimes secondary to disease- HSP, SLE, malaria, bee sting
o Proteinuira >200mg protein/mmol creatinine
o Serum albumin >25
o Oedema
o Hypercholesterolaemia
• Rare in childhood (1 in 50000 per year),median age of onset (2.5yrs) 80% <6yrs of age boys > girls

Question 14

What are the clinical signs of nephrotic syndrome?

Answer 14

o Periorbital oedema- particularly on waking, the earliest sign
o Scrotal or vulval, leg & ankle oedema
o Ascites
o Breathlessness- due to pleural effusions and abdominal distension
o Cloudy/frothy urine

Question 15

What is steroid sensitive nephrotic syndrome

Answer 15

85–90% of children with nephrotic syndrome, the proteinuria resolves with corticosteroid therapy (steroid-sensitive nephrotic syndrome)-these children do not progress to renal failure
More common in boys, Asians, often precipitated by respiratory infections

Question 16

Which features suggest it’s steroid sensitive nephrotic syndrome?

Answer 16

o	Age between 1 and 10 years
o	No macroscopic haematuria
o	Normal blood pressure
o	Normal complement levels
o	Normal renal function

Question 17

What are the complications of nephrotic syndrome (hypovolaemia)?

Answer 17

Hypovolaemia- abdo pain and feel faint
Low urinary sodium and high packed cell volume of red blood cells
requires urgent treatment with intravenous albumin as the child is at risk of vascular thrombosis and shock, increasing peripheral oedema, assessed clinically and by daily weight, may cause discomfort and respiratory compromise- if severe, this may need treatment with intravenous albumin, care must be taken with the use of colloid, as it may precipitate pulmonary oedema and hypertension from fluid overload, and also with diuretics, which may cause or worsen hypovolaemia.

Question 18

What are the complications of nephrotic syndrome?

Answer 18

Thrombosis- hypercoagulable state, due to urinary losses of antithrombin, thrombocytosis which may be exacerbated by steroid therapy, increased synthesis of clotting factors and increased blood viscosity from the raised haematocrit, predisposes to thrombosis, this may affect the brain, limbs and splanchnic circulation with potentially catastrophic results
Infection- pneumococcus
Hypercholesterolaemia- correlates inversely with the serum albumin, but the cause of the hyperlipidaemia is not fully understood

Question 19

What is the management for nephrotic syndrome?

Answer 19

oral corticosteroids (60 mg/m2 per day of prednisolone) 
after 4 weeks, the dose is reduced to 40 mg/m2 on alternate days for 4 weeks and then stopped
median time for the urine to become free of protein is 11 days

Question 20

What is the prognosis of nephrotic syndrome?

Answer 20

• If relapses are frequent, or if a high maintenance dose is required- involvement of a paediatric nephrologist is advisable as other drug therapy may be considered to enable reduction in steroid use
• Possible steroid-sparing agents include
o Immunomodulator levamisole
o Alkylating agents- e.g. cyclophosphamide
o Calcineurin inhibitors- e.g. tacrolimus and ciclosporin A
o Immunosuppressant- mycophenolate mofetil

Question 21

How is steroid resistant nephrotic syndrome managed?

Answer 21

o Diuretic therapy
o Salt restriction
o ACE inhibitors
o NSAIDs (non-steroidal anti-inflammatory drugs), which may reduce proteinuria

Question 22

What is congenital nephrotic syndrome?

Answer 22

presents in the first 3 months of life
recessively inherited
associated with a high mortality Usually due to complications of hypoalbuminaemia rather than renal failure, the albuminuria is so severe that unilateral nephrectomy may be necessary for its control, followed by dialysis for renal failure, which is continued until the child is large and fit enough for renal transplantation.