Chronic cough is one of the five most common reasons children are taken to the doctor, affecting 5% to 10% of children in the U.S. every year and accounting for 30 million office visits annually. And that's not surprising, given that coughing is a symptom of a host of health conditions.
An acute cough due to a cold or respiratory virus usually goes away within a month's time. When coughing becomes regular and persists longer, however, it may mean there's a more serious culprit behind it.
When coughing becomes chronic
Coughing is the body's natural and normal reaction to an irritant in the airway (the nose and nasal passages, pharynx, larynx, trachea and lungs). When the nerves in the airway sense an irritant — for instance, mucus, a foreign particle or even perfume — the nerves send a message to the brain to clear the breathing passages.
Sounds fine, right? But, what if the coughing does not stop after the airway has been cleared?
A daily cough that lasts more than four weeks is considered chronic and should be checked out by a doctor.
The good news is that pediatricians can typically address the common causes of a cough. If the cough persists after traditional treatment or if there are other complicating medical conditions, the pediatrician may refer the child to a specialist — like the multispecialty team at RUSH's Pediatric Aerodigestive Program, one of the first programs of its kind in Illinois.
Here, experts from the program shed light on the causes — both common and rare — of chronic coughing in children.
1. Allergies and sinusitis
Your pediatric ENT specialist will ask detailed questions about the patient's nasal symptoms to help determine whether allergies or a chronic infection may be the source of the problem.
- Children with allergic rhinitis sneeze frequently, tend to have clear mucus drainage from the nose, and may have itchy eyes.
- Chronic sinusitis, by definition, involves more than 12 weeks of symptoms. Children may complain of pain or pressure in the face, and always have thick, yellow-green nasal drainage.
Both allergic rhinitis and chronic sinusitis often lead to post-nasal drip, and the secretions that drip down the back of the throat as the child changes position can cause a cough. So often parents will describe a cough that is worse when the child first lies down at night.
The doctor also will listen to the cough for clues. In many cases, a dry cough can suggest that it's related to an allergy or asthma. A wet or productive (phlegmy) cough can sometimes indicate a problem other than asthma, like pertussis, mycoplasma or pneumonia.
Wheezing, or breathing with a whistling or rattling sound in the chest, it what most people think of when they hear asthma.
Asthma can present with a chronic cough as the only symptom however. When doing diagnostic investigations for a chronic cough reversible airflow obstruction on a pulmonary function test can be used to diagnose asthma that presents with cough as the only symptom.
A cough that is present after a child falls asleep is suggestive of asthma.
With asthma, the body's levels of cortisol — a key hormone — naturally decrease during the night. This can trigger asthmatic bronchospasm, where the air passages become inflamed and narrow.
3. Whooping cough
Pertussis, better known as whooping cough, is caused by a bacterial infection. Pertussis can cause people to cough so uncontrollably that they have to catch their breath by inhaling so deeply they make a "whooping" sound.
A cough from pertussis could last for months, and complications can be serious, including apnea (not breathing), decreased oxygen, pneumonia, seizures and death. In some cases, complications may require hospitalization for supportive care (possibly including mechanical ventilation in serious cases).
Because complications can be life-threatening in children, it is recommended that adults protect their children by getting vaccinated (in addition, of course, to making sure children get the vaccine as part of the recommended vaccination schedule).
4. Cystic fibrosis
In rare cases, a continued cough may be a sign of a more serious condition such as cystic fibrosis, a progressive genetic disease that causes persistent lung infections.
"A cough that doesn't go away can be cause for concern especially when a child also is eating voraciously and not gaining weight," says Jenifer Burke, RN, MSN, a pediatric pulmonary nurse practitioner.
Other symptoms of cystic fibrosis may include loose stools, persistent coughing, recurrent respiratory infections, prolonged symptoms of bronchiolitis (inflammation of the smallest air passages of the lungs), and recurrent/chronic rhinosinusitis (swelling and irritation of the sinus lining).
While acid reflux is typically associated with gastrointestinal symptoms such as stomach aches, heartburn and vomiting, it can also contribute to the development of chronic cough in children.
Coughing that occurs while eating or drinking — especially if the child a history of recurrent pneumonia — could be a sign of aspiration.
Aspiration occurs when swallowed food or liquids pass below the level of the vocal cords and into the lungs. "Aspiration can be due to vocal cord paralysis, or other neurologic conditions that cause decreased sensation in the upper airway," says Erin Miller, a speech-language pathologist at RUSH.
If your doctor suspects aspiration as the cause of chronic cough, your child may be referred to see a speech-language pathologist. The speech-language pathologist will perform an instrumental swallow assessment, such as a video fluoroscopic swallow study (VFSS) or a flexible endoscopic evaluation of swallowing (FEES).
6. Acid reflux
While acid reflux is typically associated with gastrointestinal symptoms such as stomach aches, heartburn and vomiting, it can also contribute to the development of chronic cough in children, according to Anil A. Kesavan, MD, a pediatric gastroenterologist at RUSH.
"Acid reflux does not cause chronic cough by itself, but it can exacerbate and worsen cough in patients with underlying respiratory disease," he says.
Stomach acids are produced to help digest food and are not meant to move upward from the stomach into the esophagus (the canal that connects the throat to the stomach), but when it happens it can trigger a cough reflex.
Reflux-related cough is typically a dry cough that happens more during the daytime when a child is in an upright position. It occurs commonly after eating and with excessive phonation (i.e., laughing, singing, talking).
Certain foods (caffeine, citrus fruits/juices, foods high in fat, tomatoes, pickled vegetables, carbonated beverages) can trigger acid reflux, which can worsen reflux-related cough.
7. A blockage in the airway
In some cases, chronic coughing could be a sign that a foreign object has become stuck in the child’s airway.
After a choking event, there is an asymptomatic period that can last up to two weeks before complications, such as pneumonia, begin to appear. If your child has a chronic cough that develops after a choking event, seek medical care immediately.
8. Habit cough
Sometimes a cough will develop in response to an irritant in the airway, but persist after the original cause has resolved.
Habit coughing is typically "honking" in nature, and it's distractible — if the child is preoccupied, the cough will disappear. The cough is also not present once the child has fallen asleep.
If other causes of chronic cough have been ruled out and habit cough is suspected, speech and behavioral therapy can be helpful in retraining the child's abnormal reflex. Giving the child sips of water when he or she feels the urge to cough can also be a helpful therapy.