Ascites (R18)

ICD-10 code R18 is used to classify ascites, a condition characterized by excess fluid buildup in the abdomen. It includes specific codes for different types of ascites based on the underlying cause, such as malignant or other forms.

The general code R18 represents ascites without further specification. For cases involving cancer-related fluid accumulation, R18.0 describes malignant ascites, identified by abnormal or malignant cells found in the peritoneal fluid. This code helps distinguish ascites caused by tumors or cancer treatment. The code R18.8 covers other ascites types, including those linked to dialysis, bile leakage, infections, metabolic causes, or complications like pancreatic ascites. It also includes terms such as hepatic ascites, hemorrhagic ascites, and refractory ascites. Coders and healthcare providers utilize these codes to document specific ascites conditions accurately in clinical records, enabling clear differentiation of causes like cancer, infection, or biochemical imbalances. Using the ICD-10 code for ascites correctly supports precise diagnosis and tailored medical management.

Instructional Notations

Includes

This note appears immediately under a three character code title to further define, or give examples of, the content of the category.

  • fluid in peritoneal cavity

Type 1 Excludes

A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

  • ascites in alcoholic cirrhosis K70.31
  • ascites in alcoholic hepatitis K70.11
  • ascites in toxic liver disease with chronic active hepatitis K71.51

Clinical Terms

The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.

Ascites

Accumulation or retention of free fluid within the peritoneal cavity.

Carcinoma, Ehrlich Tumor

A transplantable, poorly differentiated malignant tumor which appeared originally as a spontaneous breast carcinoma in a mouse. It grows in both solid and ascitic forms.

Chylous Ascites

Presence of milky lymph (CHYLE) in the PERITONEAL CAVITY, with or without infection.

Mucin-4

A transmembrane mucin that is found in a broad variety of epithelial tissue. Mucin-4 may play a role in regulating cellular adhesion and in cell surface signaling from the ERBB-2 RECEPTOR PROTEIN-TYROSINE KINASE. Mucin-4 is a heterodimer of alpha and beta chains. The alpha and beta chains result from the proteolytic cleavage of a precursor protein.

Peritoneovenous Shunt

An operation for the continuous emptying of ascitic fluid into the venous system. Fluid removal is based on intraperitoneal and intrathoracic superior vena cava pressure differentials and is performed via a pressure-sensitive one-way valve connected to a tube traversing the subcutaneous tissue of the chest wall to the neck where it enters the internal jugular vein and terminates in the superior vena cava. It is used in the treatment of intractable ascites.

Pseudomyxoma Peritonei

A peritoneal adenocarcinoma characterized by build-up of MUCUS in the PERITONEAL CAVITY. Mucus secreting cells may attach to the peritoneal lining and continue to secrete mucus. The majority of cases represent tumor spread from a primary low-grade mucinous neoplasm of the APPENDIX (NCI Thesaurus).

Receptor, ErbB-2

A cell surface protein-tyrosine kinase receptor that is overexpressed in a variety of ADENOCARCINOMAS. It has extensive homology to and heterodimerizes with the EGF RECEPTOR, the ERBB-3 RECEPTOR, and the ERBB-4 RECEPTOR. Activation of the erbB-2 receptor occurs through heterodimer formation with a ligand-bound erbB receptor family member.