6- Paediatric Nephrology (2/2) Flashcards
Nephritic syndrome
Background
- Nephritis refers to inflammation within the nephrons of the kidney
nephritis syndrome presentation
can vary in a combination of some or many of the following:
- AKI (sometimes GFR can drop drastically)
- On urine dipstick: blood +/- and/or protein+/-
o Sometimes visible haematuria
o Proteinuria <3.5g/24 hours (less than nephrotic)
- Mild to moderate oedema
- Hypertension
nephritic syndrome causes in children
Most common causes in children
- Post streptococcal GN
- IgA nephropathy
Post-streptococcal Glomerulonephritis (post-infective)
Background
- 1-2 weeks after group a B-haemolytic streptococci infection e.g. Strep pyogenes e.g. Tonsillitis
- Children aged 3-12
Pathophysiology: immune complexes made up of streptococcal antigens, antibodies and complement proteins get stuck in the glomeruli of the kidney and cause inflammation -> AKI
Investigations
- Positive throat swab
- Anti-streptolysin antibody titres in blood
Management
- 80% make a full recovery without treatment
- May require treatment with antihypertensives and diuretics if they develop hypertension and oedema
IgA nephropathy (Berger’s disease)
Background
- Related to Henoch-Schonlein Purpura -> IgA vasculitis
- Young adults and teenagers
Pathophysiology
- IgA deposits in nephrons of kidney cause inflammation (nephritis)
Investigations
- When renal biopsy is taken the histology will show IgA deposits and glomerular mesangial proliferation
Management
- Supportive treatment for renal failure
- Immunosuppressant medication
o Steroids
o Cyclophosphamide to slow progression
Polycystic kidney disease backgrounds
Two main types
1) Autosomal recessive (ARPKD)
- Presents in neonates
- Picked up on antenatal US
2) Autosomal dominant (ADPKD) – more common in adults
pathophysiology of PCKD
- Mutation in polycystic kidney and hepatic disease (PKHD1) gene on chromosome 6
- Gene codes for fibrocystin/polyductin protein complex (FPC) -> responsible for creation of tubules and maintenance of healthy epithelial tissue in kidney, liver and pancreas
Presentation of PCKD
Key features
* Cystic enlargement of the renal collecting ducts
* Oligohydramnios, pulmonary hypoplasia and Potter syndrome
* Congenital liver fibrosis
presentation of PCKD in antenatal periods
Oligohydramnios
- Lack of amniotic fluid due to reduced urine production by fetus
- Leads to Potter syndrome- dysmorphic features such as
–>Underdeveloped ear cartilage
–>Low set ears
–>Flat nasal bridge
–> Abnormalities of skeleton
Pulmonary hypoplasia -> respiratory failure shortly after birth
Polycystic kidneys
- Large cysts on kidneys can take up space in the abdomen which makes it hard for neonate to breath
- May require renal dialysis within first few days of life
Complications of PCKD
- Liver failure due to liver fibrosis
- Portal hypertension leading to oesophageal varices
- Progressive renal failure
- Hypertension due to renal failure
- Chronic lung disease
management of PCKD
Management
- Renal dialysis
prognosis of PCKD
Prognosis
- Most patients develop end stage renal failure before reaching adulthood
- 1/3 die in neonatal period
haemolytic uraemic syndrome (HUS) background
Occurs when there is a thrombosis within small blood vessels throughout the body
Classic triad of
- Haemolytic anaemia: anaemia caused by RBC destruction
- AKI: failure of kidney to excrete waste products such as urea (released when RBC breakdown)
- Thrombocytopenia: low platelets
Pathophysiology of HUS
- Triggered by bacterial toxin Shiga – e.coli 0157 or shigella
Risk factors HUS
- Use of Abx and anti-motility medications such as loperamide to treat gastroenteritis increase risk of developing HUS
Risk factors HUS
- Use of Abx and anti-motility medications such as loperamide to treat gastroenteritis increase risk of developing HUS
Presentation HUS
E. coli 0157 causes a brief gastroenteritis, often with bloody diarrhoea. The symptoms of haemolytic uraemic syndrome typically start around 5 days after the onset of the diarrhoea.
Signs and symptoms of HUS may include:
- Reduced urine output
- Haematuria or dark brown urine
- Abdominal pain
- Lethargy and irritability
- Confusion
- Oedema
- Hypertension
- Bruising
Management HUS
HUS is a medical emergency and has a 10% mortality. It needs to be managed by experienced paediatricians under the guidance of a renal specialist. The condition is self limiting and supportive management is the mainstay of treatment:
* Urgent referral to the paediatric renal unit for renal dialysis if required
* Antihypertensives if required
* Careful maintenance of fluid balance
* Blood transfusions if required
HUS prognosis
Prognosis
70 to 80% of patients make a full recovery.