Diagnostic Analysis

The blood, protein, and RBC casts in the boy’s urine indicated a primary renal disorder. The elevated creatinine and BUN levels indicated that the problem was severe and markedly affecting his renal function. Both kidneys were probably equally impaired. Intravenous pyelogram (IVP) was helpful only in ruling out Wilms tumor or congenital abnormality. Normally an IVP would not be performed in light of this patient’s impaired renal function. It is presented here for demonstration of the information it can provide. Renal ultrasound is a much safer test to visualize the kidney to exclude neoplasm. The ultrasound findings were compatible with an inflammatory process involving both kidneys. Renal biopsy was most helpful in suggesting glomerulonephritis. The history of recent pharyngitis, fever, the positive ASO titer, the positive ADB titer, and the finding of immunoglobulin IgG antibodies on the immunofluorescent stain all suggested poststreptococcal glomerulonephritis.

The patient was placed on a 10-day course of penicillin. He was given antihypertensive medication, and his fluid and electrolyte balance was closely monitored. At no time did his creatinine or BUN level rise to a point requiring dialysis. After 6 weeks, his renal function returned to normal (creatinine, 0.7 mg/dL; BUN, 7 mg/dL). His antihypertensive medications were discontinued, and he remained normotensive and returned to normal activity.

Critical Thinking Questions

1. At what point would the BUN and creatinine have signified the need for dialysis? 2. What was the cause of the patient’s hypertension? 3. What would you do if this patient had developed a swollen mouth and neck after the IVP?