September 2013

Coding for Whooping Cough
For The Record
Vol. 25 No. 12 P. 26

Pertussis, which is more commonly known as whooping cough, is a highly contagious bacterial infection of the respiratory system. Commonly caused by Bordetella pertussis, its trademark symptom is severe coughing spells followed by a high-pitched “whoop” sound during inhalation.

A vaccination is available to prevent the disease and consists of a series of five injections at the following ages: 2 months, 4 months, 6 months, between 15 and 18 months, and between 4 and 6 years. This vaccination is called DTaP and is given in combination with vaccinations for diphtheria and tetanus.

Because the immunity from the vaccination can fade away, a booster shot called Tdap is given between the ages of 11 and 18 and then every 10 years thereafter. The Tdap vaccine is similar to DTaP but with lower concentrations of diphtheria and pertussis.

Despite the availability of a vaccination to prevent whooping cough, the number of confirmed cases each year in the United States is on the rise. According to the Centers for Disease Control and Prevention, in 2012 there were more than 41,000 whooping cough cases in the United States, including 18 deaths.

The condition typically affects children who are too young to have received at least the first three vaccinations. It also may affect teenagers and adults without enough immunity to fight the bacteria and who have not received the booster shot.
It is now recommended that women receive the Tdap vaccine with every pregnancy to protect the infant from contracting the infection.

Symptoms
The initial symptoms of whooping cough resemble that of a common cold and may include a low-grade fever; mild, dry cough; nasal congestion; red, watery eyes; runny nose; and sneezing.

The symptoms start to worsen after one to two weeks and progress to include an uncontrolled and prolonged cough caused by the accumulation of thick mucus. The coughing causes vomiting, red or blue face, fatigue, and a whoop sound.

Complications
Some patients may experience complications from whooping cough, and most are caused by the strenuous coughing. Common complications include an abdominal hernia, broken blood vessels affecting the skin or eyes, and fractured or bruised ribs.

Infants with whooping cough may experience complications such as apnea, brain damage, dehydration, ear infections, pneumonia, and seizures.

ICD-9-CM Code Classifications
Whooping cough is classified to ICD-9-CM category 033. A fourth-digit subcategory is available to identify the organism involved, as follows:

• 033.0, Bordetella pertussis;

• 033.1, Bordetella parapertussis; and

• 033.8, Whooping cough due to other specified organism, which also includes Bordetella bronchiseptica.

If the organism is not specified, assign code 033.9. Pneumonia associated with whooping cough is classified as code 484.3, Pneumonia in whooping cough, sequenced as the secondary diagnosis.

If the patient receives a vaccination against pertussis alone, assign code V03.6. If the vaccination is combined with DTaP, then assign code V06.1. Other codes that are available for vaccinations given in combination include the following:

• V06.2, DTaP with typhoid-paratyphoid;

• V06.3, DTaP with poliomyelitis; and

• V06.8, DTaP with hemophilus influence B.

Diagnosis
Whooping cough may be confirmed by a nose or throat culture to identify the organism. The physician also may order blood tests. If the patient’s white blood cell count is elevated, it may indicate the patient is fighting an infection. In addition, the physician may order a chest X-ray to determine whether the patient also has pneumonia.

Treatment
Since whooping cough is a bacterial infection, it may be treated effectively with antibiotics for two weeks. For teenagers and adults, the treatment may be carried out at home. However, infants with whooping cough typically are hospitalized to treat the infection and any associated symptoms and complications.

Coding and sequencing for whooping cough depend on the physician documentation in the medical record and application of the Official Coding Guidelines for inpatient care. Use specific AHA Coding Clinic for ICD-9-CM and American Medical Association CPT Assistant references to ensure complete and accurate coding.

— This information was prepared by Audrey Howard, RHIA, senior consultant with 3M Consulting Services. 3M Consulting Services is a business of 3M Health Information Systems, a supplier of coding and classification systems to more than 5,000 healthcare providers. The company and its representatives do not assume any responsibility for reimbursement decisions or claims denials made by providers or payers as the result of the misuse of this coding information. More information about 3M Health Information Systems is available at www.3mhis.com or by calling 800-367-2447.

 

ICD-10-CM Coding for Whooping Cough
The coding classification for whooping cough is similar in ICD-10-CM. The one major difference is that instead of assigning a separate code for any associated pneumonia as a secondary diagnosis, there now is a combination code for whooping cough and pneumonia. Category A37 has codes available for whooping cough caused by Bordetella pertussis, Bordetella parapertussis, and other Bordetella species (including Bordetella bronchiseptica). The fifth character of 1 will identify that there is associated pneumonia.

— AH