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14.1  Hematuria

The dipsticks are very sensitive for blood and can be positive at <5 RBCs per high power field. Evidence of red blood cells in the urine should be confirmed by microscopy which should be performed on fresh urine. Contrast microscopy has been advocated with anatomically normal red blood cells suggesting bleeding of lower urinary tract origin as distinct from dysmorphic red cells suggesting a higher (glomerular) source. However, the test is very rarely applied in pediatric practice. Microscopy of urine can help in diagnosis with the presence of red cell casts indicating glomerular bleeding.

Causes of “red urine” need to be excluded:

•Urate crystals, especially in young infants giving “pink” nappies

•Food coloring, e.g., beetroot or blueberries

•Hemoglobinuria and intravascular hemolysis

•Myoglobinuria, e.g., in rhabdomyolysis

•Drugs, e.g., Rifampicin

•External source, e.g., menstrual blood loss

•Fictitious – consider if no cause found.

14.1.1  Important Points in the History

•Symptoms suggestive of UTI, e.g., fever, frequency, and dysuria. UTI quoted as commonest cause for macroscopic and microscopic hematuria.

•Urine red (more likely to be a local cause) or tea/coke colored (more likely to be glomerular with oxidized blood)

•Is the hematuria at the beginning or end of the stream (bladder or urethral cause)

•Is there colicky abdominal pain (suggesting stones)

•History of trauma

•Is there history of coagulopathy such as easy bruising

•Is there a family history of hematuria or of renal disease and deafness (Alport’s syndrome) or sickle cell disease

Chapter 14.  Hematuria and Proteinuria 149

•Examination will include palpation of the abdomen for abdominal masses, skin rashes and blood pressure

14.1.2  Causes of Hematuria

•Urinary tract infections:

––Bacterial

––Viral (e.g., adenovirus in outbreaks)

––Schistosomiasis (history of foreign travel)

––Tuberculosis

•Glomerular

––Post-infectious glomerulonephritis

––IgA nephropathy, Henoch-Schonlein purpura, SLE

––Hereditary – thin basement membrane, Alport’s syndrome

•Urinary tract stones: hypercalciuria

•Trauma

•Other renal tract pathology

––Renal tract tumor

––Polycystic kidney disease

•Vascular

––Renal vein thrombosis

––Arteritis

•Hematological: coagulopathy/sickle cell disease

•Drugs – cyclophosphamide

•Exercise induced

14.1.3  Investigations

When evaluating childhood hematuria it is important to identify serious and progressive conditions. If macroor microscopic hematuria is found in the setting of an acute illness such as UTI then it needs to be confirmed by urine culture and the urine tested after the acute illness. Glomerulonephritis will require a full “nephritis work-up.” However, if the child presents with asymptomatic “benign” hematuria without growth failure, hypertension, edema, proteinuria, urinary casts or renal impairment then investigations can be arranged in the outpatient clinic.

150 A.R. Watson

•Urine

––Microscopy to confirm RBCs and look for casts

––Culture for bacteria and possibly viruses

––Protein : creatinine ratio to define level of proteinuria if present (normal <20 mg protein/mmol creatinine) on an early morning urine

––Calcium : creatinine ratio on second morning urine to exclude hypercalciuria (normal <0.7 mmol calcium/ mmol creatinine)

•Bloods

––U&E/creatinine/albumin/calcium/phosphate/alk phos

––FBC/clotting

––Complement: C3/C4

––ASOT and antihyaluronidase B titers

––ANA/anti-dsDNA and ANCA titers if nephritis suspected

•Radiology

––Ultrasound of urinary tract of all patients with hematuria

––Further radiology will depend upon clinical situation and initial ultrasound

•Test urine of parents and other children in clinic (hereditary causes)

•Cystoscopy – not routine and rarely indicated in children. Heavy isolated hematuria, recurrent fresh bleeding and abnormal findings on ultrasound may provide indication

14.1.4  Management

•If obvious cause such as UTI treat with antibiotics but will require at least renal tract ultrasound.

•If impaired renal function, proteinuria or family history refer to pediatric nephrology unit.

•If suspicious lesion on ultrasound of urinary tract or intermittent macroscopic hematuria (with IgA nephropathy excluded in an older child) then discuss with radiology/urology.

•If no cause found and normal renal function, BP and no proteinuria monitor in clinic at 6-monthly intervals.

•If persistent microscopic hematuria after one year or change in any of the above parameters then refer to pediatric nephrology unit for consideration of renal biopsy.2