IgA nephropathy

Question 1

what is the definition of IgA nephropathy?

Answer 1

IgA nephropathy (IgAN) is defined by the presence of dominant or co-dominant mesangial IgA immune deposits, often accompanied by C3 and IgG in association with a mesangial proliferative glomerulonephritis of varying severity.

Question 2

what is the pathophysiology of IgA nephropathy?

Answer 2

Abnormality in IgA glycosylation

Question 3

what are the key presentations of IgA nephropathy?

Answer 3

Gross haematuria
Flank pain
Acute upper respiratory tract infection
About 50% of patients with IgA nephropathy present with recurrent episodes of visible haematuria after an upper respiratory tract infection or gastroenteritis; approximately one third of patients have invisible haematuria and mild proteinuria.

Question 4

what are the first line and gold standard investigations for IgA nephropathy?

Answer 4

Kidney biopsy is required for definitive diagnosis.
Isolated haematuria = no biopsy
Proteinuria >500mg/day = kidney biopsy
Microscopy = light - mesangial proliferation, immunofluorescence and electron - IgA deposits

Question 5

what is the differential diagnosis for IgA nephropathy?

Answer 5

IgA vasculitis

Question 6

how is IgA nephropathy managed?

Answer 6

Renin-angiotensin system inhibitors are widely used to reduce proteinuria, particularly if hypertension and/or proteinuria is present, and they have been shown to help preserve kidney function.
Steroids for depleted kidney function (glucocorticoids)

Question 7

what are the complications of IgA nephropathy?

Answer 7

Acute or chronic kidney failure may develop, IgA vasculitis