Final answer:
Hematuria, abdominal pain, arthralgia, and purpura in a child after a viral upper respiratory infection could be indicative of IgA nephropathy. Treatment may include medications for blood pressure and inflammation, as well as dietary modifications.
Step-by-step explanation:
The symptoms of hematuria, abdominal pain, arthralgia, and purpura in a child after a viral upper respiratory infection can be indicative of a condition called IgA nephropathy. IgA nephropathy is an autoimmune kidney disorder characterized by the deposition of IgA antibodies in the kidneys, leading to inflammation and damage. Treatment for IgA nephropathy may include medications to control blood pressure and reduce inflammation, as well as dietary modifications to minimize kidney stress.