N25 ICD-10-CM Code: Disorders resulting from impaired renal tubular function

N25 is the ICD-10-CM diagnosis code for disorders resulting from impaired renal tubular function. N25 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering other disorders of kidney and ureter (n25-n29).

Header codes like N25 cannot be reported on claims directly, they organize child codes that share clinical context but the actual diagnosis must be coded to the highest level of specificity supported by the documentation. Coders should look at N25's child codes and select the one that matches the patient's documented presentation, since payers reject header codes submitted as the primary diagnosis. For risk adjustment workflows, header codes never contribute to a Medicare Advantage member's RAF score on their own; only billable child codes that happen to map to a payment HCC affect risk-adjusted plan payments.