Acute kidney failure with lesion of renal medullary [papillary] necrosis

This code signifies a sudden and severe decline in kidney function, specifically attributed to damage within the renal medulla, characterized by necrosis (tissue death) of the renal papillae. This condition impairs the kidneys' ability to filter waste products from the blood, leading to an accumulation of toxins.

Use this code when documentation clearly indicates acute kidney failure and explicitly identifies renal medullary or papillary necrosis as the underlying cause. This diagnosis is often supported by imaging studies (e.g., ultrasound, CT scan) showing papillary necrosis, urinalysis findings, and elevated serum creatinine and BUN levels.

• Ensure documentation specifies "acute" kidney failure; chronic kidney failure with papillary necrosis would be coded differently.
• Distinguish from other causes of acute kidney failure; the specific lesion of renal medullary/papillary necrosis must be present.
• Code any underlying conditions contributing to the papillary necrosis (e.g., analgesic nephropathy, sickle cell disease, diabetes mellitus) as additional diagnoses.