What is a common complication of untreated streptococcal throat infections?

Rheumatic fever is a well-known complication that can arise from untreated streptococcal throat infections, particularly those caused by Group A Streptococcus. This autoimmune condition typically develops a few weeks after the initial infection and can affect the heart, joints, skin, and nervous system. The body's immune response to the streptococcal bacteria can lead to inflammation in various tissues, especially the heart, which may result in rheumatic heart disease—a serious condition that can cause lasting damage to heart valves.

In contrast, while pneumonia, scarlet fever, and sepsis can be associated with streptococcal infections, they do not directly stem from untreated throat infections in the way that rheumatic fever does. Pneumonia is more typically associated with respiratory infections, while scarlet fever is actually a manifestation of streptococcal infection itself, characterized by a distinct rash. Sepsis represents a systemic response to infection that can occur with a variety of pathogens, not specifically as a consequence of untreated strep throat. Thus, rheumatic fever specifically connects the untreated throat infection with a serious long-term complication, highlighting the importance of early recognition and treatment of streptococcal throat infections.