Glomerulonephritis

Glomerulonephritis

Glomerulonephritis is an inflammatory condition of the kidney’s filtering units, the glomeruli. It’s characterized by a combination of haematuria, proteinuria, hypertension, and sometimes a reduction in kidney function. The inflammation of the glomeruli makes them “leaky,” allowing blood cells and protein to pass into the urine, while also reducing the glomerular filtration rate, which can lead to fluid retention and hypertension.

 

Causes

  • Post-streptococcal Glomerulonephritis (PSGN): This is the most common cause in children. It typically presents 2-3 weeks after a Group A streptococcal throat infection or 4-6 weeks after a skin infection.

  • IgA Nephropathy (Berger’s disease): The most common cause of chronic glomerulonephritis. It often presents with recurrent episodes of visible haematuria that coincide with or follow an upper respiratory tract infection.

  • Alport Syndrome: A genetic condition affecting type 4 collagen, leading to an abnormal glomerular basement membrane. It is associated with progressive kidney disease and bilateral sensorineural hearing loss.

  • Systemic Conditions: Glomerulonephritis can be a feature of a wider systemic illness, such as Henoch-Schönlein purpura (HSP) or Systemic Lupus Erythematosus (SLE).

 

Clinical Assessment

  • History: Ask about recent infections (throat, skin, or GI), reduced urine output, and any puffiness around the face or ankles. It’s also important to check for red or cola-coloured urine.

  • Examination: Check the child’s blood pressure and assess for oedema, especially around the face. A full skin and ENT examination is also essential.

 

Investigations

  • Urine Tests: A bedside urine dipstick will show haematuria and proteinuria. A urine microscopy is crucial to confirm the presence of red blood cells and look for any red cell casts, which indicate glomerular bleeding.

  • Bloods:

    • U&Es: To assess kidney function.

    • Complement Levels: C3 is typically low in PSGN, but normal in IgA nephropathy and Alport syndrome.

    • ASO Titre: This test is raised in PSGN and indicates a recent streptococcal infection.

  • Imaging: A renal tract ultrasound can be used to assess kidney size and exclude any structural abnormalities.

  • Renal Biopsy: This is reserved for atypical cases or for those with persistent haematuria, significant proteinuria, or declining kidney function.

 

Management

The management principles are based on the underlying cause and the severity of the symptoms.

  • Supportive Care: This includes monitoring urine output, weight, and blood pressure.

  • Blood Pressure Control: Hypertension may require treatment with ACE inhibitors or calcium channel blockers.

  • Referral: A referral to a paediatric nephrologist is essential for all cases of glomerulonephritis to guide further management, especially in cases of impaired kidney function, significant proteinuria, or hypertension.