Renal Failure or Renal Insufficiency?
By Barbara A. Rubin, MEd, RHIA
Because of how they’re classified by ICD-9, renal insufficiency and chronic renal failure carry vague and confusing applications; for the novice coder, it may well be easier to solve the question of which came first, the chicken or the egg. Robert Gold, MD, has pointed out (www.dcbainc.com/library/acute_renal_failure_07p.html) that even the Coding Clinic Guidelines have only sparse and vague information on the clarity of the two conditions. “There had not been much in the way of guidance in the medical world and Coding Clinicjust references to elevation of creatinine or decrease in renal function. And how do we differentiate failure from insufficiency?” he wrote.
The Foundation for IgA Nephropathy indicates that renal failure is also referred to as renal insufficiency; they are not two distinct conditions but synonymous in meaning and diagnosis. Renal insufficiency occurs when the kidneys no longer have enough healthy tissue to function properly, with the key section being “no longer have enough healthy tissue.” This infers the kidney must have been in a diseased condition for a period of time. Therefore, one can extrapolate the fact that insufficiency would apply more to a chronic condition than an acute phase.
However, please reference when there is confusing and/or unclear documentation, the coder is always to query the physician (Coding Clinic, second quarter, 2000, page 17).
ICD-9 creates many debates about whether renal insufficiency may be independent of chronic renal failure and possibly a codeable condition in addition. The Coding Clinic Guideline, fourth quarter, 2005, pages 79-80 states, “Effective October 1, 2005, chronic renal insufficiency is indexed to code 585.9, Chronic kidney disease, unspecified, while acute renal insufficiency continues to be indexed to code 593.9, Unspecified disorder of kidney and ureter. Prior to this change, both acute and chronic renal insufficiencies were indexed to code 593.9.”
There is a significant difference between acute renal insufficiency and chronic renal insufficiency. Acute renal insufficiency is an often-reversible condition caused by medications and/or an injury. According to the Foundation for IgA Nephrology, the term renal failure is beginning to be replaced by renal insufficiency when it is associated with chronic kidney disease.
One clinical characteristic of renal insufficiency is that the kidneys can no longer store electrolytes and filter out waste products into the urine, supporting the coder’s understanding that the condition is referring to a chronic one. According to the above references, the condition of renal insufficiency is a chronic renal failure.
With the implementation of ICD-10, this issue will be clearly resolved. Acute renal insufficiency located in the Alphabetical Index refers one to N28.9, Disorder of kidney and ureter, unspecified, which includes renal insufficiency acute. However, there is an Excludes 1 note in the tabular under this code. Excludes 1 note by definition means “Not coded here ‘chronic renal insufficiency (N18.9).’” Therefore, the correct coding of acute renal insufficiency per directions would be to utilize chronic renal insufficiency N18.9. In ICD-10, there is clear distinction that renal insufficiency will be coded as a chronic condition.
Generally, chronic insufficiency is prompted by certain underlying illnesses or diseases; in most cases, the common causes are diabetes and hypertension. It is usually caused by fluid and waste products accumulating in the body because the kidneys are damaged, a condition that affects other body systems and prevents them from functioning normally. ICD-10 clearly makes this fine distinction and alleviates the confusion of the terms being independent of the condition.
— Barbara A. Rubin, MEd, RHIA, is a national quality manager and educator at Kforce and a certified ICD-10 “Train the Trainer.”