Renal disease - Manchester University NHS Foundation Trust

This section deals with clinical conditions associated with renal disease which are covered by the Immunology department. For each clinical condition, the relevant immunological tests are listed together with a short explanation of their use

Acute renal presentations

Immunological processes are implicated in many renal diseases. In several situations, diagnosing and treating immunological processes can halt or reverse renal impairment. For this reason the following tests may be offered on an urgent basis, provided an urgent request is made by phone.

Immunological test	Clinical condition	Turnaround time
Anti-neutrophil cytoplasmic antibody (ANCA)	Vasculitis	Same day
Glomerular basement membrane antibodies	Goodpasture’s disease	Same day
Antinuclear antibody (ANA), includes anticentromere	SLE and other connective tissue diseases	Same day
Serum and urine electrophoresis	Myeloma	Results next day
Complement C3, Complement C4	Immune complex nephritis	Results next day

Chronic renal presentations

The same tests are also useful for the diagnosis of chronic renal disease.

Cryoglobulinaemia may also be excluded in some patients with chronic renal failure. This test requires very careful specimen handling and it may be helpful to screen for cryoglobulinaemia by doing C4; if C4 is normal, cryoglobulinaemia is very unlikely. C3 nephritic factor can cause membranoproliferative disease. The laboratory can refer samples to a laboratory that measures C3 nef directly, but this is a complex test with delayed results. We recommend checking C3 first; if C3 is normal, C3 nef is very unlikely to be present.

Some of these tests are also used to monitor renal disease (ANCA, C4). In SLE, monitoring anti-DNA antibody levels and complement C4 is more useful than monitoring ANA.

The half life of IgG antibodies is about three weeks, so most forms of immunosuppressive treatment will not produce rapid changes in autoantibodies and repeat sampling more than every six weeks is probably unhelpful.

The exceptions are plasmapheresis and administration of high dose IVIg, which cause rapid and clinically meaningful fluctuations in autoantibody level. In these situations, more frequent testing of ANCA or anti-GBM is appropriate.

Patient information is available from the National Kidney Federation.

Screening for Glomerulonephritis

Relevant immunological tests on the first occasion:

Additional tests may help categorise the type of glomerulonephritis.

Membranoproliferative glomerulonephritis

Relevant immunological tests:

Complement C3
C3 nephritic factor (only if C3 very low)

Serum C3 levels are low in some forms of membranoproliferative glomerulonephritis reflecting the presence of the circulating autoantibody C3 nephritic factor which binds and activates C3 convertase.

Glomerulonephritis

Relevant immunological tests:

p-ANCA associated glomerulonephritis is the common form of Necrotising crescentic glomerulonephritis, reflecting different vasculitic causes.

Goodpasture’s syndrome

Relevant immunological test: Glomerular basement membrane antibodies

A combination of renal and lung involvement may suggest Goodpasture’s syndrome due to the presence of antibodies to the glomerular basement membrane (GBM).

IgA Nephropathy

Relevant immunological tests: Immunoglobulins (IgG, IgA, IgM)

Serum IgA may be raised in IgA nephropathies including Henoch Schönlein purpura.

Nephrotic syndrome

Relevant immunological tests: Immunoglobulins (IgG, IgA, IgM)

Serum immunoglobulins may be low in poorly selective proteinuric forms of nephrotic syndrome (focal glomerulonephritis).

ATG monitoring: Patients receiving ATG therapy have T cell numbers (% and absolute counts) monitored daily. For the result to be available by noon, it is essential that the sample is received in the laboratory no later than 10:30am.

(Last reviewed June 2019)