Nephritic Syndrome and Urine Examination

Examination of fresh urine as part of routine physical examination may show the presence of protein, blood or pus cells in the patients affected by nephritic syndrome. In many cases the renal disease is occult and is often detected during the routine physical examination. It is important to understand that acute nephritis, nephrotic syndrome and renal failure may occur either as a result of intrinsic disease of the kidneys or in association with a systemic disease. Metabolic and functional disturbances such as hypertension, uremia (elevated level of urea in blood), or anemia may cause occult renal disease.

Hypertension along with mild edema (swelling), apparently as suborbital puffy eyes is characteristic clinical feature of nephritic syndrome. Hematuria (blood in urine) with or without proteinuria (protein in urine), oliguria (low urinary output) and impaired excretory function are other characteristic features. The urine may be red or brownish to smoky brown in color in patients affected by nephritic syndrome. Microscopic examination of fresh urinary sediment in these patients may reveal very high count of dysmorphic red blood cells (dysmorphic RBCs). The detection of RBCs in the urinary casts signifies that the hematuria comes from the kidneys (renal parenchyma). Proteinuria may vary from 0.3g to 3.0g daily. Urinary sodium level (Na⁺ level) tends to be low due to sodium retention as a result of impaired excretory function by the kidneys. Retention of sodium and water in these patients lead to increased circulatory blood volume and cause hypertension. The uncontrolled hypertension may lead to cardiomegaly along with mild renal pain. Patients affected by nephritic syndrome need renal biopsy examination and specialized treatment under the supervision of a nephrologist.