Nephrology and genitourinary Flashcards
Aetiology of acute nephritis
Caused by increased glomerular cellularity, restricting glomerular blood flow and therefore leads to decreased filtration
Post-infectious - eg. streptococcus
Vasculitis: HSP SLE Wegener Granulomatosis Microscopic Polyarteritis
IgA nephropathy Goodpasture syndrome (rare..)
Clinical features of acute nephritis
Oliguria
Hypertension - may lead to seizure
Oedema - characteristacally around eyes
Haematuria and proteinuria
Management of acute nephritis
Monitor water and electrolyte balance.
Administer diuretics if necessary
If there is rapidly progressive glomerulonephritis (rare, but can occur with any acute nephritis, except post-streptococcal) which can cause irreversible renal failrure over weeks or months
-may need renal biopsy and treatment with immunosuppression and plasma exchange
Prognosis of acute nephritis
0.5% mortality
5% long-term abnormalities
Features of Henoch-Schönlein Purpura
HSP
Rash - purpura -
buttocks, extensor surfaces of legs, arms and ankles
Arthralgia (knees and ankles)
Periarticular oedema (joint swelling - knees and ankles)
Abdo pain - haematemesis and melaena
Glomerulonephritis - microscopic/macroscopic haematuria (80%)
Often there is fever
in which age group does HSP occur
3-10yrs
2x as common in boys
Often preceded by an URTI
Long term complications of HSP and follow up
With severe proteinuria, there may be nephrotic syndrome.
All children with renal involvement will be followed up for a year to detec those with persisting urinary abnormalities (5-10%).
HTN and declining renal function may develop after an interval of several years
Risk factors for progressive renal disease in HSP
Renal biopsy will determine whether treatment is necessary, but:
Heavy proteinuria
Oedema
HTN
Deteriorating renal function
Management plan for HSP. Prognosis
Same as acute nephritis.
Long-term follow up for severe renal involvement
<1% of HSP patients will progress to end-stage renal failure, but prognosis is worse in older children
Follow up in 6 months if normal urinalysis
What are the commonest causes of acute glomerulonephritis in childhood?
Post-streptococcal/infection nephritis
Familial nephritis
Vasculitis
SLE
What is post-streptococcal nephritis
usually follows a streptococcal sore throat or skin infection
Diagnosed by evidence of recent streptococcal infection (culture, raised ASO/anti-DNAse B titres)
Low C3 complement
Good longterm prognosis
What is Familial nephritis
Commones is Alport syndrome - X-linked recessive
Progresses to end-stage renal failure by early adult life in males
Nerve deafness
Ocular defects
Mother may have haematuria
Characteristic symptoms of vasculitis
(HSP, polyarteritis nodosa, microscopic polyarteritis, Wegener granulomatosis)
Fever Malaise Rash Weight loss Arthropathy
Renal involvement may be severe and rapidly progressing
Treatment of vasculitis
steroids plasma exchange IV cyclophosphamide (for months)
Epidemiology of SLE
Mainly presents in adolescent girls and young women
Commoner in Asians and Afro-caribbeans
What is SLE
Presence of multiple autoantibodies
Antibodies to double-stranded DNA (C3 and C4 may be low)
Haematuria and Proteinuria are indicators for renal biopsy (determines intensity of immunosuppression)
Investigations in patients presenting with acute glomerulonephritis
Electrolytes and creatinine (renal function)
FBC - infection, anaemia
Urinalysis (infection, protein, blood)
Urine culture
Complement levels
ASO titre
Anti-DNAse B
Serum IgA measurement
Renal biopsy is the single most effective diagnosis
Renal ultrasonography usually performed to exclude other causes
What is enough to diagnose post-streptococcal glomerulonephritis without the need for renal biopsy
Fitting history
Low C3
Postive ASO
Anti-DNAse B
What histopathology does IgA nephropathy share with HSP?
Episodes of macroscopic haematuria
commonly associated with URTI
Same histological findings and management
Aetiology of nephrotic syndrome
Can be secondary to systemic disease:
HSP vasculitides SLE Infections (malaria) Allergens (eg. bee sting)
Clinical signs of nephrotic syndrome
Periorbital oedema
Particularly on waking
Scrotal or vulcal, leg, ankle oedema
Ascites
Breathlessness - due to pleural effusions and abdominal distension
Cloudy/frothy urine
Define nephrotic syndrome
Proteinuria > 200mg protein/mmol creatinine
Serum albumin (hypoalbuminaemia) <2.5g/dl
Oedema that begins in the face
Hyperlipidaemia
Name the commonest types of nephrotic syndrome in childhood
Steroid sensitive nephrotic syndrome
Steroid resistant nephrotic syndrome
Congenital nephrotic syndrome
Incidence of nephrotic syndrome
1 in 50000 per year
Median age of onset is 2.5 yrs
boys > girls
How much of nephrotic syndrome is responsive to steroid therapy?
85-90%
It is the commonest type
These children do NOT progress to renal failure
What may precipitate steroid-sensitive nephrotic syndrome
URTI
associated with atopy
Features that suggest steroid-sensitive nephrotic syndrome
Age 1-10 years NO macroscopic haematuria Normal blood pressure Normal complement levels Normal renal function
Complications of nephrotic syndrome
Hypovolaemia
Thrombosis (due to urinary loss of antithrombin and raised haematocrit)
Infection (especially pneumococcus)
Hypercholesterolaemia
Indicators for hypovolaemia in nephrotic shock
Abdo pain
Feel faint
Peripheral vasoconstriction
Low urinary sodium (due to retention)
High packed cell volume of RBCs
Requires urgent treatment with IV albumin to prevent vascular thrombosis and shock
Management of steroid-sensitive nephrotic syndrome
Oral corticosteroids (60mg/m2 per day of prednisolone)
If no atypical features, reduce the dose the dose after 4 weeks.
This should happen over 4 weeks.
Median time for urine free of protein is 11 days
Prognosis of steroid sensitive nephrotic syndrome
1/3 resolve directly
1/3 will relapse infrequently
1/3 will relapse to steroid-dependent
Relapse identified by parent on urine testing
What are causes of steroid-resistant nephrotic syndrome
Focal segmental glomerulosclerosis (most common)
Mesangiocapillary glomerulonephritis (haematuria and low complement level)
Membranous nephropathy (associated with Hep B)
Management of oedema in nephrotic syndrome
Diuretic therapy
Salt restriction
ACE inhibitors
NSAIDs may reduce proteinuria
What is congenital nephrotic syndrome
Presents in first 3 months of life
High mortality due to hypoalbuminaemia - unilateral nephrectomy may be needed, followed by dialysis for renal failure (until fit enough for transplant)
Initial management of nephrotic syndrome
Fluid management: (difficult because there is fluid overload with possible hypovolaemic shock)
Fluid restriction
Diuretics
Albumin infusions
Treat underlying disease with Prednisolone and other immunosuppressants
Management of complications: Infections Thrombosis Side effects of treatment Renal failure
What are the atypical features of nephrotic syndrome
No response to 4-8 weeks of corticosteroid therapy
Age <12 months or >12 years HTN Haematuria Low C3 complement Renal failure
What should be done in atypical presentation of renal failure
Renal biopsy
-renal histology
