IgA nephropathy

Today we discussed IgA nephropathy. A few key points:

For a general approach to renal failure, click here.

Some important parts of assessment
1. Previous creatinine
2. Hx: drugs, volume, systemic disease (lung, joint, skin, fever...)
3. Volume status assessment, assesment for dialysis indications
4. Urinalysis: blood, protein, casts, cells, eosinophils
5. Urine lytes, osmolality
6. U/S of abdo to r/o obstruction
7. Serology: ANA, anti-GBM, ANCA, C3, C4 (if appropriate)

IgA nephropathy is the most common form of primary glomerulonephritis in the world.
Henoch-Schonlein purpura is a vasculitis associated with IgA deposition and may be a "systemic" form of IgA nephropathy (often with purpura, abdominal pain, arthralgias). Other associated conditions are celiac disease, IBD, and many other autoimmune conditions, and HIV.

Most commonly presents in 20's or 30's, more common in men than women (~5:1)

Many pts with IgA nepphropathy are asymptomatic. Most common ways of coming to clinical attention are

1) microscopic hematuria or proteinuria, which may be intermittent or

2) episodes of macroscopic hematuria or cola-coloured urine, which are classically associated with upper respiratory tract infection (but not commonly).

Firm diagnosis can only be made with biopsy, but which patients need biopsy is controversial.

Course is highly variable, from totally benign to rapidly progressive renal failure.

Worse prognostic indicators are:
1) degree of proteinuria
2) HTN
3) males

Conservative tx is BP management, ACE-I or ARB, fish oil (some evidence).

Specific tx is for crescentic/rapidly decreasing GFR. Cyclophosphamide, chlorambucil, steroids.

Link:
Click here for a NEJM review of IgA nephropathy