An 8-year-old boy presents with headaches, dizziness, and malaise. He was seen for a severe sore throat 2 weeks ago. Physical examination reveals facial edema. The blood pressure is 180/110 mm Hg. A 24-hour urine collection demonstrates oliguria, and urinalysis shows hematuria. Which of the following best describes this patient's medical condition?

This case is illustrative of nephritic syndrome in the setting of poststreptococcal glomerulonephritis. Nephritic syndrome is characterized by hematuria (either microscopic or visible grossly), variable degrees of proteinuria, and decreased glomerular filtratio. It results in elevations of serum blood urea nitrogen and creatinine, as well as oliguria, salt and water retention, edema, and hypertension. Glomerular diseases associated with the nephritic syndrome are caused by inflammatory changes in glomeruli, such as infiltration by leukocytes, hyperplasia of glomerular cells, and, in severe lesions, necrosis. The other choices are not related to streptococcal pharyngitis. Choices B, C, and E do not present with hematuria.Diagnosis: Postinfectious glomerulonephritis, nephritic syndrome