Pediatric Coding Alert

You Be the Coder:

INH Therapy

Test your coding knowledge. Determine how you would code this situation before looking at the box below for the answer.


Question: When someone has a positive Mantoux (PPD) test and a negative chest x-ray and comes in for a visit to initiate INH (isonicotinic acid hydrazide, called isoniazid) therapy, what should we code? We code a moderate level office visit but what diagnosis should we use? We cant use tuberculosis because the chest x-ray was negative, and if we use a V code we probably wont get paid.

Andrew S. Baumel, MD
Framingham Pediatrics, Framingham, Mass.


Answer: The best diagnosis code is 795.5 (nonspecific reaction to tuberculin skin test without active tuberculosis). Its correct, and it gets paid.

Unfortunately, there is a slight chance that this could negatively affect a childs future insurance with the tuberculosis label. Even though the diagnosis is without active tuberculosis, it would get in the medical record database, which all insurers have access to, and some future carrier may well interpret this as tuberculosis, and restrict any coverage that may be related to that condition. Health insurance obtained through employers would not have any such restrictions, however.

And if the child (or adult, by the time other insurance is applied for) is treatment-free for a certain period of time, the companywhether its life or health insurancewill provide coverage. The bottom line: you should not be afraid to use the 795.5 diagnosis. It is the right code, and avoiding it would be fraudulent. The only time its important to avoid certain diagnoses is during the rule-out period. Some pediatricians discuss the risk of insurance labeling with a parent and suggest that all visits related to that condition be paid in cash to avoid the necessity of submitting insurance claims. Not only would this be rather expensive in the case of a year of INH therapy, but it is to be avoided as an unethical practice.

Also, you have to document in the chart what the diagnosis is each time the child comes in during the year of INH therapy to be followed for the therapy, as well as a diagnosis for any orders for follow-up x-rays. Clinically, a child with a positive PPD test is considered seroconverted, meaning the child has been exposed to TB and the immune system is or has been battling the infection.

The INH treatment is designed to assist the body in eliminating any remaining TB infection. All patients who have TB will have a positive PPD test, but only a few patients with a positive PPD test have TB. If a PPD test is positive, the diagnosis of TB is made by a chest x-ray, sputum stains and cultures, and by clinical symptoms.

As a secondary diagnosis code, you could also use V71.2 (observation and evaluation for suspected conditions not found; observation for suspected tuberculosis).