16.2 Haematuria
2 Haematuria can be caused by urinary infection, glomerular disease, tumours, congenital abnormalities and coagulopathies.
Introduction
Blood in the urine (haematuria) may be visible to the naked eye (macroscopic) or be detected only on dipstick testing and/or urine microscopy (microscopic). It may be found in isolation or associated with other urine abnormalities such as proteinuria, crystals and casts. It is essential to consider urinary tract infection (UTI) as a possible cause and, if confirmed, to manage accordingly (see Chapter 16.4).
Note that small numbers of red cells are normally excreted in urine.
Macroscopic haematuria exists when visible to the naked eye and confirmed on testing as being blood.
Microscopic haematuria in the setting of an acute febrile illness can be normal. UTI should be excluded by urine culture and the urine tested again after the acute illness has passed.
Causes of glomerular haematuria include:
• glomerulonephritis (GN) (including nephritis in multisystem disorders, e.g. systemic lupus erythematosus (SLE));
Causes for non-glomerular haematuria include:
