Children with which condition are more prone to infections due to low C3 levels?

Children with post-streptococcal glomerulonephritis are more prone to infections due to low C3 levels because this condition is characterized by inflammation of the kidneys following a streptococcal infection, which can lead to a decrease in complement levels, particularly C3. The complement system is crucial for opsonization and clearance of pathogens; thus, reduced C3 levels can impair the immune response, making the individual more susceptible to infections.

In post-streptococcal glomerulonephritis, the immune complex deposition can trigger complement activation and subsequent consumption, leading to lower levels of C3. This condition is commonly seen after infections with certain strains of Streptococcus, such as those causing pharyngitis or skin infections (impetigo), and the decrease in C3 is a direct consequence of the body’s response to these antigens.

In contrast, other conditions listed, such as renal tubular acidosis, minimal change disease, and acute kidney injury, do not have the same direct impact on complement levels or do not primarily involve complement-mediated mechanisms that lead to increased susceptibility to infections. Renal tubular acidosis is more associated with acid-base imbalances rather than complement function, while minimal change disease usually