Is K66.1 a billable ICD-10-CM code?

Yes. K66.1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does K66.1 sit in the tabular list?

Diseases of the digestive system (K00-K95), in the block Diseases of peritoneum and retroperitoneum (K65-K68).

What cannot be coded together with K66.1?

K66.1 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter.

K66.1

K66.1 — Hemoperitoneum

Billable / specific codeICD-10-CM

K66.1 is a billable, specific ICD-10-CM code for hemoperitoneum. It is valid for submission on a claim.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

traumatic hemoperitoneum (S36.8-)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

retroperitoneal hematoma (K68.3)
retroperitoneal hemorrhage (K68.3)

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Peritoneal hematoma
Peritoneal hemorrhage

Excludes2 inherited from the categories above K66.1

Also inherited, and the opposite of Excludes1: these conditions are not part of K66.1, but a patient can have both, so you may code both.

Written on K66 — Other disorders of peritoneum

ascites (R18.-)
peritoneal effusion (chronic) (R18.8)

Risk adjustment

K66.1 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Medicare coverage

K66.1 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56421Billing and Coding: CT of the Abdomen and Pelvis

How K66.1 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to K66.1.

Hemoperitoneum
Hematoma›peritoneal
Hemorrhage, hemorrhagic›intraperitoneal
Hemorrhage, hemorrhagic›mesentery
Hemorrhage, hemorrhagic›omentum
Hemorrhage, hemorrhagic›peritoneum, peritoneal
Hemorrhage, hemorrhagic›intrapelvic›male

Code history

K66.1 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share K66. If K66.1 is not quite right, the correct code is usually one of these.

Questions about K66.1

Is K66.1 a billable ICD-10-CM code?: Yes. K66.1 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does K66.1 sit in the tabular list?: Diseases of the digestive system (K00-K95), in the block Diseases of peritoneum and retroperitoneum (K65-K68).
What cannot be coded together with K66.1?: K66.1 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter.