2021 ICD-10-CM Code K35.8

Other and unspecified acute appendicitis

Version 2021

Not Valid for Submission

K35.8 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of other and unspecified acute appendicitis. The code is not specific and is NOT valid for the year 2021 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Unspecified diagnosis codes like K35.8 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

ICD-10:K35.8
Short Description:Other and unspecified acute appendicitis
Long Description:Other and unspecified acute appendicitis

Code Classification

Specific Coding for Other and unspecified acute appendicitis

Non-specific codes like K35.8 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10 codes with a higher level of specificity when coding for other and unspecified acute appendicitis:

  • BILLABLE CODE - Use K35.80 for Unspecified acute appendicitis
  • NON-BILLABLE CODE - K35.89 for Other acute appendicitis
  • BILLABLE CODE - Use K35.890 for Other acute appendicitis without perforation or gangrene
  • BILLABLE CODE - Use K35.891 for Other acute appendicitis without perforation, with gangrene

Information for Patients


Appendicitis

The appendix is a small, tube-like organ attached to the first part of the large intestine. It is located in the lower right part of the abdomen. It has no known function. A blockage inside of the appendix causes appendicitis. The blockage leads to increased pressure, problems with blood flow, and inflammation. If the blockage is not treated, the appendix can burst and spread infection into the abdomen. This causes a condition called peritonitis.

The main symptom is pain in the abdomen, often on the right side. It is usually sudden and gets worse over time. Other symptoms may include

Not everyone with appendicitis has all these symptoms.

Appendicitis is a medical emergency. Treatment almost always involves removing the appendix. Anyone can get appendicitis, but it is more common among people 10 to 30 years old.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)