What condition is characterized by sudden hematuria, proteinuria, and decreased glomerular filtration rate?

Acute glomerular nephritis is characterized by the sudden onset of hematuria, proteinuria, and a decrease in glomerular filtration rate (GFR). This condition often results from various causes, including post-infectious processes (such as following streptococcal infections), autoimmune disorders, or other inflammatory responses. The impairment of the glomeruli leads to leakage of blood and protein into the urine (manifested as hematuria and proteinuria) due to damage, swelling, or inflammation in the kidney structures.

The reduction in GFR indicates that the kidneys are not filtering blood as efficiently as they should. As a result, patients experiencing acute glomerular nephritis may exhibit signs of kidney dysfunction alongside the urinary symptoms, such as swelling, hypertension, or fluid retention. This triad of symptoms specifically points to acute glomerular nephritis, making it the most fitting answer for the given clinical scenario.