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The most likely reason for blood in a child's urine would be infection. Other symptoms that would be associated with this include abdominal pain
(a more common symptom in children than in adults), more frequent urination, pain with urination and/or fever.
Injury to the penis or urethra or irritation of the urethra (the tube where the urine passes out) can also cause blood in the urine.
Much less common causes of bleeding include bleeding disorders (usually we will see other problems such as bleeding gums, frequent bloody noses), kidney stones (typically associated with back pain
--quite severe!), tumors (not common) or kidney disease.
His pediatrician will first do a urine test to look for infection. Again, this is the most likely cause of his blood and is easily treated. If it is infection, the blood will go away once the infection is gone.
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