The correct answer is N13.0. The ICD-10-CM code N13.0 is used for hydronephrosis due to obstruction of the ureteropelvic junction. In this case, the patient is diagnosed with hydronephrosis caused by an acquired occlusion of the ureteropelvic junction, which is appropriately coded using N13.0. This diagnosis specifically relates to the condition where urine flow is blocked between the kidney and ureter, leading to kidney swelling (hydronephrosis).

N13.1 refers to hydronephrosis due to congenital obstruction of the ureteropelvic junction. Since the patient ' s condition is described as " acquired, " this code would not be applicable.

N13.2 refers to hydronephrosis due to nephrolithiasis (kidney stones), which is not the case here.

N13.6 relates to other specified obstructive uropathy, which does not fit the description of acquired ureteropelvic junction obstruction with infection.

Thus, N13.0 is the most accurate code for this patient’s condition.

Reference topics: ICD-10-CM for Hydronephrosis and Obstructive Uropathy; Ureteropelvic Junction Obstruction Codes.