Acute post streptococcal glomerulonephritis is an immunologic response of the kidney to infection, characterized by the sudden appearance of edema, hematuria, proteinuria and hypertension . It is essentially a disease of childhood that accounts for approximately 90% of renal disorders in children.
Group A beta hemolytic Streptococcus ( Strains M1, M4, M12)
Molecular Mimicry– Antibodies against streptococcal antigens react with normal glomerular antigens leading to immune complex formation & complement activation. Release of leukocyte, macrophage, cytokines further increases injury.
- Age- School age children , uncommon below 3 years
- Gender- More common in boys
- Subclinical episodes are more common than overt disease especially during epidemics
- Onset is rapid with puffiness around eyes and pedal edema.
- Cola colored wine lasts for few hours to few days.
- Hypertension – Patients should be monitored for symptoms of encephalopathy like blurred vision, headache, seizures etc.
- Acute phase resolves in 6-8 weeks
Light Microscopy– Enlarged and ischemic glomeruli, capillary loops narrowed with mesangial cell proliferation and neutrophil infiltration.
Immunofluorescence– Granular deposits of lgG and complement along capillary wall ( ‘Lumpy-Bumpy’ deposits ).
Election Microscopy– Deposits (humps) on sub epithelial side of glomerular basement membrane & in mesangium.
- Urine Analysis– Dysmorphic RBC, Polymorphonuclear leukocytes, RBC cast, Proteinuria 1-2 +
- Increased Blood urea and creatinine
- Hyponatremia, Hyperkalemia, Metabolic acidosis
- Normocytic anemia, Raised ESR, Low grade hemolysis
- Low (3 levels which normalizes by 8-12 weeks
- Evidence of prior streptococcal infection– ↑ASO titers ( 80% ) or anti-DNase B (skin infection )
- Chest X-ray – Prominent bronchovascular marking indicating hypervolemia
- Mild oliguria with normal BP can be managed at home
- Sodium, potassium and fluid restriction till blood levels of creatine reduce and wine output increases.
- Prevent overhydration as it can precipitate left ventricular failure
- Modest edema = Oral frusemide ( 1-3mg/ kg)
- Pulmonary edema-IV frusemide (2-4 mg/kg)
- Daily weight and wine output monitoring
- Hypertension –
- Mild – Fluid and salt restriction
- Antihypertensive include Amlodipine, Nifedipine
- Hypertensive emergency – IV Nitroprusside & Labetalol
- Left Ventricular Failure – Control Hypertension and induce diuresis by IV frusemide. If no diuresis noted start dialysis
- Severe renal failure
- Prolonged oliguria
- Fluid overload
- Life threatening electrolyte disturbance
- Penicillin given if active pharyngitis or pyoderma is present