Internal Medicine Coding Alert

Published on Tue Dec 18, 2012 PDF

Coding under ICD-10 will depend on the level of detail providers note.

When your internist diagnoses mononucleosis, you have a single diagnosis choice under ICD-9: 075 (Infectious mononucleosis). The same code applies to glandular fever, monocytic angina, or Pfeiffer’s disease.

Once ICD-10 goes into effect in October 2014, your choices will be more detailed. Begin coding by determining the type of infection involved:

• B27.0 -- Gammaherpesviral mononucleosis
• B27.1 -- Cytomegaloviral mononucleosis
• B27.8 -- Other infectious mononucleosis
• B27.9 -- Infectious mononucleosis, unspecified.

Next, you’ll move to whether the patient is experiencing related complications or has another condition, such as polyneuropathy. The fifth-digit classifications for each code category will be:

0, without complication

1, with polyneuropathy

2, with meningitis

9, with other complication.

Definition: Mononucleosis (commonly called "mono") is an infection caused by the Epstein-Barr virus. The virus is found in saliva and mucus and is passed through kissing or exposure to a cough, sneeze or sharing food utensils (such as drinking glasses, spoons and forks) with someone who has mono. Symptoms (including fever, sore throat, fatigue, weakness, and swollen glands in the neck or armpits) in young children are generally mild, while symptoms in adolescents and young adults tend to be more severe. The illness is most common in patients ages 15-35.

Documentation: The physician might make an initial diagnosis of mononucleosis based on the symptoms listed above. Blood tests can confirm mono and rule out other possible causes of the symptoms, such as strep throat. Early blood tests might show an increase in one type of white blood cells that might have an atypical appearance. More specific blood tests can confirm the diagnosis of mono.

Once ICD-10 goes into effect, physicians will need to be more detailed in their documentation of infectious mononucleosis. They’ll need to specify the exact type and also note complications and/or associated diseases, such as polyneuropathy (a condition that involves damage to multiple nerves) and/or meningitis (inflammation of the membranes surrounding the brain and spinal cord).

Remember: When coding, only report a diagnosis of mononucleosis once blood tests have confirmed the patient’s illness