Chronic Glomerulonephritis are a group of disorders in which the glomeruli are predominantly involved due to an inflammatory process which does not abate; becoming indolent and frequently leading to glomerular destruction and End Stage Renal Disease (ESRD).

In majority of cases the cause or initiating injury is not known, whilst in some an infectious agent such as Streptococcal or Staphylococcal infection (throat, VP shunt, sub-acute bacterial endocarditis, abscesses, etc.), viral infection like Hepatitis B, Hepatitis C, rarely CMV, HIV, EB viruses, parasitic infections like malaria and immunological diseases like SLE, HSP, Wegner's granulomatosis, Polyarteritis nodosa (in whom clinical clues such as joint pains, skin rash nodules, sinusitis, bronchitis are important for correct diagnosis). Hence before labelling a patient as primary or idiopathic CGN, serologic and immunologic tests eg. ASO Titre, ANA, AntidssDNA, ANCA, serum C3 and C4 levels, Anti-phosholipid antibodies (APLA), anticardiolipin, anti-SM, anti-GBM and immune complexes should be examined.

The hallmark of chronic glomerulonephritis is proteinuria with or without hematuria which is persistent and may be accompanied with edema, hypertension, azotemia or renal failure.

Screening of school children for presence of proteinuria +/- hematuria is one of the methods of diagnosis of glomerulonephritis in asymptomatic stage. In advanced countries like Japan, Taiwan, Korea, yearly urinalysis is mandatory and if 3-4 urinalysis are abnormal further investigations are asked to establish the diagnosis of chronic GN. This is not cost-effective in our country.

One can suspect Chronic GN in a child if

• Acute glomerulonephritis is not completely resolved by 6-12 months i.e. urine shows proteinuria + hematuria, serum C3 is persistently low, hypertension, azotemia persist.
 
• Persistant urinary abnormalities - proteinuria, hematuria, isolated micro/macro hematuria
 
• Hypertension, nephritis syndrome
 
• Puffiness of eyes & edema, nephrotic syndrome
 
• Azotemia
 
• Systemic diseases like Henoch's Schonlein Purpura, SLE, Polyarteritis Nodosa, pulmonary-renal syndrome (Good Pasture's Syndrome).
 
• Nephritic syndrome

Investigations in chronic GN - Renal function tests, serum C3, ANA, AntidssDNA. Kidney biopsy is an important tool for diagnosis of chronic GN. Various types of histopathological pictures are seen on light and electron microscopy. Immunofluorescence microscopy shows +ve immunofluorescence against IgG, IgM, IgA or C3 in various combinations in glomerular capillary basement membrane or mesangium.

Typically, full house or IgG + C3 - In SLE
IgG + IgA - Henoch Scholein Purpura
IgG + C3+++ - Membrano-proliferative GN

Presence of electron-dense deposits in subepithelial, subendothelial, intra-membranous or mesangial region are seen in EM studies. As the disease progresses, sclerosis of glomeruli occurs ending in complete destruction of both kidneys. The progression may take few months to years during which increase in BUN, S. creatinine, hypertension, proteinuria +/- edema precedes uremic manifestations. Measures to halt the progression by protein restriction, ACE inhibitor use, control of hypertension, etc. can be attempted with limited success.

Last created on 6-11-2000
Last updated on 01-07-2006