B27.9 - Infectious mononucleosis, unspecified

Version 2023
Short Description:Infectious mononucleosis, unspecified
Long Description:Infectious mononucleosis, unspecified
Status: Not Valid for Submission
Version:ICD-10-CM 2023
Code Classification:
  • Certain infectious and parasitic diseases (A00–B99)
    • Other viral diseases (B25-B34)
      • Infectious mononucleosis (B27)

B27.9 is a non-specific and non-billable ICD-10 code code, consider using a code with a higher level of specificity for a diagnosis of infectious mononucleosis, unspecified. The code is not specific and is NOT valid for the year 2023 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 B27.9 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.

Clinical Information

Specific Coding for Infectious mononucleosis, unspecified

Non-specific codes like B27.9 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 infectious mononucleosis, unspecified:

  • BILLABLE CODE - Use B27.90 for Infectious mononucleosis, unspecified without complication
  • BILLABLE CODE - Use B27.91 for Infectious mononucleosis, unspecified with polyneuropathy
  • BILLABLE CODE - Use B27.92 for Infectious mononucleosis, unspecified with meningitis
  • BILLABLE CODE - Use B27.99 for Infectious mononucleosis, unspecified with other complication

Patient Education

Infectious Mononucleosis

Infectious mononucleosis, or "mono", is an infection usually caused by the Epstein-Barr virus. The virus spreads through saliva, which is why it's sometimes called "kissing disease." Mono occurs most often in teens and young adults. However, you can get it at any age. Symptoms of mono include:

Sometimes you may also have a swollen spleen. Serious problems are rare.

A blood test can show if you have mono. Most people get better in two to four weeks. However, you may feel tired for a few months afterward. Treatment focuses on helping symptoms and includes medicines for pain and fever, warm salt water gargles and plenty of rest and fluids.

[Learn More in MedlinePlus]

Code History