Final answer:
The presence of dysmorphic RBCs or RBC casts in urine suggests different renal conditions; dysmorphic RBCs are often associated with glomerular damage, while RBC casts point to renal tubule pathology. Further urinalysis can help diagnose conditions like urinary tract infections and potential autoimmune disorders.
Step-by-step explanation:
When a patient is peeing blood, the examination of urine is essential to determine the underlying cause. The presence of dysmorphic red blood cells (RBCs) or RBC casts in the urine can indicate different renal pathologies. Dysmorphic RBCs, which are malformed, can suggest glomerulonephritis, indicating that the glomeruli are damaged and allowing for the distortion of RBCs as they pass through. On the other hand, the presence of RBC casts, which are cylindrical structures composed of coagulated protein with embedded RBCs, points to a pathology within the renal tubules, such as severe glomerulonephritis or vasculitis.
Additional urine investigations include the detection of proteins, white blood cells, bacteria, cellular casts, and crystals. Conditions such as nephritis, trauma, tuberculosis of the kidney, and kidney stones can lead to hematuria, where both RBCs and white blood cells (WBCs) are found upon microscopic examination of urine. The presence of white blood cells typically suggests a urinary tract infection.
If the clinical context suggests autoimmune issues, such as in the case of Kerry who developed rashes after sun exposure and was diagnosed with proteinuria, hemoglobinuria, and a low hematocrit, further rheumatological evaluation may be warranted to assess for autoimmune conditions like systemic lupus erythematosus (SLE).