Calculus of kidney

This code signifies the presence of a kidney stone, also known as nephrolithiasis. These are hard deposits made of minerals and salts that form inside the kidneys, often causing pain, hematuria, and potential obstruction of the urinary tract.

Apply this code when documentation clearly indicates the diagnosis of a calculus (stone) located within the kidney. This diagnosis is typically supported by imaging studies such as ultrasound, CT scan, or KUB X-ray, along with clinical symptoms like flank pain or microscopic hematuria.

• Differentiate from calculi in other parts of the urinary tract (e.g., ureter, bladder) which have distinct codes.
• Do not use for a history of kidney stones if no current stone is present; instead, consider Z87.440 (Personal history of calculus of kidney).
• Always review documentation for laterality (left, right, bilateral) if specified, though ICD-9-CM 592.0 does not offer laterality specificity.