The causes, medical and surgical, of blood in the urine are so manifold that the more one studies the subject the more is one inclined to the belief that a thorough understanding of hematuria means a comprehensive knowledge of diseases of the whole body. Although hematuria brings to mind, first, neoplasm, tuberculosis and calculus, and then trauma, acute inflammation and nephritis, there is finally a long series of rarer causes of this common finding of medical examination.
The literature is enormous. Since the war, numerous articles have appeared presenting illuminating reports of unusual cases with a proved etiology, or offering new points of view concerning old problems. The general tendency marks a growing reaction against the use of the words essential and idiopathic as applied to hematuria. Most urologists will agree that essential or idiopathic hematuria does not exist, if one considers sharply the real meaning of the words, and
STEVENS AR. HEMATURIAS OF OBSCURE ORIGIN. JAMA. 1922;79(16):1302-1305. doi:10.1001/jama.1922.02640160022007