Postinfectious Cough

I am not a huge baseball fan to begin with, and when I am, I route for the Nationals.  Thus, I pay little attention to the New York Yankees, and was not aware that Yankee player Mark Teixeira had been suffering with a cough for the past month until it the story from the New York Times came through one of my Twitter feeds. According to the story:
"Mark Teixeira had a battery of tests performed Wednesday to determine the nature of his violent and persistent cough, and he received good news. Teixeira, who has been wracked by the cough for about a month, said he was found to have nothing more serious than severe congestion in his bronchial passageways." 
Mr. Teixeira was prescribed prednisone (not something I would recommend for this) and is expected to recover soon. In addition, the doctors at New York-Presbyterian/Columbia hospital in Manhattan performed a CT scan, a lung function tests, blood tests and cultures during their work up (though I am sure the Yankees can afford this). The Times does not mention the diagnosis other than to say that the baseball player had "severe inflammation in my bronchial passageways."

I blog about this because this is one of the most common things I see in the primary care setting, it is often misunderstood and therefore misdiagnosed, it is very easily treated and there is virtually no research on this disease.

Mr. Teixeira likely has what is known as postinfectious cough. Here's the typical patient presentation:
Young healthy patient gets a typical upper respiratory tract infection (URI): cough and congestion, headache, feels ill and low grade fever. URI resolves in a matter of days, but there is a persistent cough that is getting worse, and won't go away.  Cough is usually worse at night, and the patient can't exercise because it makes them cough. On occasion the cough is so bad that the patient is winded easily and sometimes the patient thinks they may be wheezing, though they have no history of asthma.

According to the American College of Chest Physician which published evidence-based clinical practice guidelines back in 2008, the diagnosis of post infectious cough should be considered when a patient complains of cough that has been present following symptoms of an acute respiratory infection for at least 3 weeks,but not more than 8 weeks.  And while the cause of the postinfectious cough is not known, it has been thought to be due to the extensive damage of cells lining the lung and widespread airway iinflammation of the upper and/or lower airways. The good news is that this usually goes away by itself, the bad news is that it can take weeks or even months, and can be quite disruptive to patients lives; desk jockeys and baseball players alike.

To me one of the most incredible things about this illness is the lack of data on effective treatments. The ACCP review cited above did an extensive review of the literature and found very few studies that looked which treatments worked best. Given the lack of data, here is my take on the appropriate diagnosis and treatment:

Diagnosis can be made without an extensive workup when the clinical presentation is consistent with that described above and there are no other complicating factors that would indicate other possibilities. A chest X-ray may be all that is necessary to rule out any underlying severe disease and is reasonable in a patient who has been coughing for more than two weeks.

Since symptoms are caused primarily by inflammation and hyperresponsiveness/bronchoconstriction in the lungs (which is what we see in asthma), then treatment is likely best with something that treats both inflammation and bronchoconstriction in the lungs, such as an inhaled corticosteroid/long-acting beta agonist like Advair (which is commonly used in asthma).  Of note, Advair (or other ICS/LABA combinations) have not been approved by the FDA for the treatment postinfectious cough and there is no data on the use of ICS/LABA's for the treatment of postinfectious cough.  However, this is a common sense approach to the problem based on what we know about the cause, and from clinical experience I can tell you this approach works remarkably well.  Use of Advair for postinfectious cough may be the single most common off-label use of any prescription product.
There are two additional important points.  First, since inflammation can persist for weeks, it is important that Advair be used for at least 4 weeks.  If stopped too soon, before inflammation has completely resolved, symptoms may return.  This is very important, because primary care physicians who decide to use ICS/LABA inhalers for postinfectious cough may give patients a medication sample rather than a prescription.  Though the drug companies that make these products used to make samples with a month's supply of medication, most inhaler samples today have only 1-2 weeks of therapy.  Secondly, if symptoms have resolved and the patient has taken the inhaler for 4-6 weeks, the patient can safely stop the inhaler.  If symptoms return, the patient should be brought back for pulmonary function testing as this may be a new presentation of asthma.