R18 is a non-billable ICD-10-CM category code for ascites, so it cannot be submitted on claims. Use a more specific code from this category instead, such as R18.0 and R18.8. As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established.
Code Identity
Code Classification
Specific Coding for AscitesOverview
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Includes
- fluid in peritoneal cavity
Type 1 Excludes
- ascites in alcoholic cirrhosis K70.31
- ascites in alcoholic hepatitis K70.11
- ascites in toxic liver disease with chronic active hepatitis K71.51
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
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.
Clinical InformationClinical
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.
Patient EducationClinical
Liver Diseases
Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Code HistoryHistory
Questions About R18Overview
Is R18 (Ascites) a billable code?
No. This is a category header that groups the codes for ascites, and headers cannot be submitted on claims. Claims for ascites need a more specific code from this category, such as R18.0 and R18.8.
Can R18 be a principal diagnosis?
Use it with care. This is a symptom code, so once a definitive diagnosis explaining the ascites is established, that condition takes the principal position instead.
