What is a nonsuppurative complication of streptococcal infection that remains unaffected by the treatment of the primary infection?

Postinfectious glomerulonephritis is a nonsuppurative complication that may occur following a streptococcal infection, particularly after pharyngeal or skin infections caused by certain strains of Group A Streptococcus. This condition results from an immune-mediated response to the streptococcal antigens, leading to inflammation of the glomeruli in the kidneys, characterized by symptoms such as hematuria, edema, hypertension, and often a decrease in urine output.

Importantly, this complication can arise after the acute phase of the primary streptococcal infection has been treated, rendering the treatment of the primary infection ineffective in preventing the development of postinfectious glomerulonephritis. The immune response that triggers this complication is not directly influenced by the eradication of the streptococci, which distinguishes it from other potential complications that might resolve with appropriate antibiotic therapy.

In contrast, acute rheumatic fever is another nonsuppurative complication, but it is associated with the infection itself and generally follows a similar timeline to the pharyngeal infection. Scarlet fever, while a consequence of streptococcal infection, is characterized by a distinctive rash and is linked to the toxin produced by the bacteria