Dialysis Encounter ICD-10-CM codes

Z99.2 (dependence on renal dialysis) is a status code and is always secondary. The reason for the dialysis encounter is the kidney disease itself, so a routine hemodialysis session or the monthly ESRD physician service (90960 to 90962) is coded N18.6 first with Z99.2 second. When hypertension or diabetes caused the kidney failure, the combination code comes first: I12.0 (hypertensive CKD with ESRD) then N18.6 then Z99.2, or E11.22 then N18.6 then Z99.2. The guidelines presume the hypertension-CKD link, so I12.0 is used even when the provider does not spell out the connection.

Category Z49 covers preparatory and monitoring encounters, not the dialysis treatment itself. Z49.01 and Z49.02 are the visits for fitting and adjusting an extracorporeal or peritoneal dialysis catheter, and Z49.31 and Z49.32 are the adequacy testing encounters (Kt/V or urea clearance) for hemodialysis and peritoneal dialysis. These are first-listed for that specific service, with N18.6 and Z99.2 after them.

Z99.2 should appear on every claim for a dialysis patient, including visits unrelated to the kidneys, because it is a risk adjustment factor and it changes how many payers process the claim. Missing Z99.2 is a common HCC gap. Noncompliance with dialysis is coded Z91.151 (due to financial hardship) or Z91.158 (other reason) when documented, and it supports the additional work of managing a patient who misses sessions.

A patient who has received a working kidney transplant is no longer Z99.2. Report Z94.0 (kidney transplant status) with the current N18 stage if residual CKD is documented; per the guidelines, CKD after transplant is not by itself a transplant complication, so T86.1x codes are reserved for documented rejection or failure. Access-site complications such as a clotted AV fistula are coded to T82.x and sequenced first when they are the reason for the visit.