Cough, Chronic Cough, Rhinitis and Sinusitis - a Primer for Patients, Physician Assistants, Nurse Clinicians & Physicians
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Web Links & References / Table of Drugs used to treat rhinitis & sinusitis / 10 Common Myths, Misconceptions, Errors and Mistakes about Chronic Cough / Chronic throat clearing
Unfortunately there is much confusion and disagreement among physicians about diagnosis and treatment of upper airway inflammation. Confusion is mainly about diagnosis, disagreement mainly about treatment. This web site is devoted to clarifying these issues as much as possible, and to helping patients with chronic cough get proper treatment. (For list lovers, see 10 Common Myths, Misconceptions, Errors and Mistakes about Chronic Cough.)
This web site is written for the lay reader, but will also be of interest to health care providers who see patients with chronic cough: physician assistants, nurse clinicians, physicians. To further help medical professionals I have referenced many statements to the medical literature, and also provided a core reading list in the References. (These connected web sites are a work in progress, and will not be complete until this sentence no longer appears.)
To illustrate the division of the respiratory system, put a finger at the top of your breast bone, at the base of your neck; you can feel a 'notch' at this point (called the surprasternal notch). Above the notch is the upper airway system, encompassing the nose, mouth, sinuses, back of the throat, larynx (voice box), and trachea. Below the notch (and inside your chest) is the lower airway system, which includes both lungs and all their branching airways; these airways are called bronchi and bronchioles, and they lead to the alveoli where fresh oxygen actually enters the bloodstream.
The following web sites show both a drawing of the sinuses and a sinus CT scan:
Drawing of the sinuses and a normal sinus CT scan
Detailed drawings of sinuses,
plus normal and abnormal sinus CT scans
While the most common source of mucus is in the nose and sinuses, the major cough centers are in other parts of the respiratory system; they are in the back of the throat (pharynx), the voice box (larynx), the wind pipe (trachea), and large airways of the lungs (bronchi). When mucus drips down from the nose and sinuses and touches these cough centers, nerves are stimulated that cause cough. (Mucus can also form in the lungs, which is the case in patients with asthma and chronic bronchitis. When that happens nerves in the bronchi are stimulated, resulting in cough.)
Mucus dripping from the nose or sinuses is called post nasal drip (PND). PND is the most common cause of chronic cough. If mucus stayed in the nasal passages and sinuses -- if it did not drip into the back of the throat and down toward the lungs -- then rhinitis and sinusitis would be an uncommon cause of cough.
RHINITIS |
SINUSITIS |
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DEFINITION |
Inflammation of the nasal passages |
Inflammation of the sinuses (air cavities in the head) |
SYMPTOMS |
'Cold symptoms': stuffy nose, nasal discharge, feeling of mucus in back of throat (post nasal drip), cough |
Same as rhinitis, plus: facial pain, fever, more severe or intractable cough. Most patients with sinusitis will have nasal inflammation as well (i.e., rhinosinusitis). Note: the only symptom of many patients with chronic sinusitis may be chronic cough. |
MAJOR CAUSES |
Viral infection, allergy, rarely bacterial infection |
Viral infection, bacterial infection, fungal infection, allergy, blockage by polyps. Sinusitis becomes 'chronic' when there is inadequate treatment and/or inadequate drainage of sinuses |
TREATMENT |
Extremely variable: OTC decongestants, nasal sprays, prescription decongestants commonly prescribed. The longer symptoms continue, the more likely antibiotics will be prescribed. (Click here for list of commonly-used drugs for rhinitis/sinusitis) |
Antibiotics are mainstay of treatment of bacterial sinusitis; however, because it is difficult to differentiate viral from bacterial sinusitis, virtually all patients with "sinusitis" or "rhinosinusitis" are treated with antibiotics. Also used are same drugs and remedies given for rhinitis. In addition, oral steroids (prednisone, methylprednisolone) are often used for chronic sinusitis, to decrease the inflammation. (Click here for list of commonly-used drugs for rhinitis/sinusitis) |
RELATIONSHIP TO ASTHMA |
Viral infection is a major cause of asthma, so viral rhinitis may be a prelude to asthma attacks in susceptible patients (mainly people who already have a history of asthma). Asthma can also develop following viral rhinitis. Finally, some patients suffering primarily from asthma also have concomitant rhinosinusitis. |
Viral infection is major cause of asthma, so viral sinusitis may be a prelude to asthma attacks in susceptible patients (mainly people who already have a history of asthma). Asthma can also develop following sinusitis. Finally, some patients suffering from asthma also have concomitant rhinosinusitis. |
USEFUL WEB SITES |
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BOOKS ON SUBJECT(with links to Amazon.com) |
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See books on Sinusitis ------> |
Disease perspective
Symptom perspective
Various studies show anywhere from 38% to 87% of cases of chronic cough are from post nasal drip (either the sole cause of a major contributor; see following references):
In my experience, the higher number for PND (87%) is closer to what we see in actual practice. The number two cause in various studies is asthma (ranging from 14% to 43%), followed by gastroesophageal reflux (10% to 40%), and chronic bronchitis (0 to 12%). The higher numbers add up to more than 100% since multiple causes of cough were found in many patients.
In these and other studies, more than one cause of chronic cough was found in 18% to 72% of patients. Given that multiple causes are often present, treatment for one condition (e.g., post-nasal drip) may improve cough but not cure it until another cause is found and treated (e.g., acid reflux).
They are all effective, and the one prescribed seems to depend as much on formulary considerations (i.e., cost to the health care provider) as on physician preference.
- sinusitis or chronic rhinitis plus post-nasal drip in 56% of patients
- chronic bronchitis in 18%
- asthma in 14%
- gastro-esophageal reflux (GERD) in 5%
- post nasal drip and GERD in 6%
- asthma and GERD in 1%
By applying specific therapy the authors were able to successfuly cure the cough in 79/87 patients (91%).
Another study, from Saudi Arabia found the following diagnoses (either sole or contributory cause) in 100 outpatients with chronic cough:
- rhinosinusitis in 60%
- asthma in 26%
- gastro-esophageal reflux in 9%
- postinfectious cough in 8%
- bronchiectasis in 5%
(Chronic cough at a non-teaching hospital: Are extrapulmonary causes overlooked?, by Al-Mobeireek AF, et. al. Respirology 2002 Jun;7(2):141-146)
The authors concluded: "...chronic persistent cough is a common benign disorder that rarely requires specialized investigations and is easily treated once the causes are identified. The multiplicity of causes and extrapulmonary triggers of chronic persistent cough, particularly rhinosinusitis, are often overlooked. The principal causes in our series remain the same as in studies elsewhere, namely rhinosinusitis, asthma and GERD."
These two foreign studies are in line with experience in the U.S. The majority of patients with chronic cough have rhinosinusitis.
A given patient with upper airway inflammation -- visiting a family practice physician, an internist, an ENT physician, an allergist, and a pulmonary specialist -- could well end up on 5 different regimens for the same symptoms! In fact, all five specialties do get involved in treating patients with rhinitis/sinusitis/chronic cough. To this end, throughout my web site you will find links to other web sites, articles, and books authored by or for the different groups of treating physicians.
It is common for patients with chronic cough to be referred to another physician, which explains why pulmonary specialists see so many patients with this complaint. Allergists also get a lot of referrals for this problem. Allergists and pulmonologists refer cough patients as well, especially to ENT physicians. And ENT physicians who cannot help a problem through surgical means will often refer the patient to a pulmonary specialist, allergist, or back to the original primary care doctor.
The result is that patients with chronic cough of more than a month's duration will invariably see at least two different doctors, sometimes three. The root problem is that chronic cough can be difficult to both diagnose (especially if there is more than one cause) and treat (treatment is often a process of trial and error).
In a word, complex. Asthma is a disease manifested by excessive mucus production in the lungs. In fact most asthmatics also have mucus in their sinuses. Usually this is from a viral infection or allergy, the same conditions that most commonly trigger an asthma attack. Thus patients 'with asthma' will commonly also have inflammation of their sinuses.
On the other hand, rhinitis and sinusitis can be the triggers of asthma. That is,
patients without any asthma history can develop asthma AS A RESULT OF
rhinitis and/or sinusitis. Simplistically, this seems to occur from
constant dripping of mucus into the lungs, triggering an asthma reaction. The
actual mechanism, however, is unknown. (See
Guerra S, et al.
Rhinitis as an independent risk factor for adult-onset asthma.
J Allergy Clin Immunol 2002;109:419-25;
Epidemiologic evidence for
asthma and rhinitis comorbidity, by Leynaert, et al.)
Sometimes asthma is treated maximally and still doesn't get better. When this happens, we will often check to see if the sinuses are 'impacted' or blocked to the extent that they are continuing to cause asthma symptoms despite maximal treatment. Sinusitis is definitely one of the conditions doctors need to evaluate in cases of intractable asthma (see Hidden factors in asthma, by Somerville LL. Allergy Asthma Proc 2001;22:341-45).
Note that DRUGS USED TO TREAT ASTHMA are different from DRUGS FOR RHINOSINUSITIS, with one exception: steroids. Steroids, also called 'corticosteroids', include the drugs prednisone and methylprednisolone [Medrol Dose Pak]). Steroids are commonly used for both severe asthma and protracted rhinosinusitis.
Symptoms and physical exam may suffice to make the diagnosis. Facial pain, purulent nasal discharge, fever, headache, chronic cough -- all suggest the diagnosis and warrant treatment. When symptoms are not clear cut, physicians will often order x-rays of the sinuses. There are two types -- conventional sinus x-rays, now infrequently used and considered by some as obsolete; and sinus CT scan, which gives a far better picture of the sinues than conventional x-ray. An abnormal sinus CT scan, along with compatible symptoms will suffice to make the diagnosis. A third way is for an ENT surgeon to put a probe into the sinus openings (going through the nose) to see if pus is coming out of the openings (other physicians generally do not do this procedure).
A 43-year-old woman was evaluated for chronic cough of a month's duration. It started with a 'cold', for which she took OTC medication. When the cold didn't get better, she was given a course of the antibiotic azithromycin, by her primary care physician. The cough improved a little, but when the antibiotic stopped the cough recurred. She was then referred. She gave no history of asthma or any respiratory disease. She is a non-smoker and her husband does not smoke. She gave no symptoms to suggest stomach acid reflux. She is on blood pressure medication, but not the type typically associated with cough. Her cough is mainly dry, i.e., not productive of mucus. Yet she often feels mucus "dripping down the back of my throat," as she explaied. She is not ill and is able to work full time as a librarian. However, the cough is quite bothersome, and colleagues at work have commented on it often. She is at her 'wit's end' about what to do. Exam is mostly unremarkable. There is minimal nasal congestion but she can breathe through her nose. There is no sinus tenderness. Her ears are normal and her lungs are clear. A chest x-ray two weeks ago was read as normal. Diagnosis: Probable rhinosinusitis, starting out as a viral infection, now complicated by inflammation in the sinuses and back of the nose, dripping into her lungs and causing chronic cough. AT THIS POINT TREATMENT WOULD LIKELY VARY AMONG PHYSICIANS. BASED ON MY EXPERIENCE I
WROTE PRESCRIPTIONS FOR THE FOLLOWING. She returned a week later 'all better.' At that point she was almost finished with the prednisone and antibiotic, and had stopped the OTC decongestant. I told her to call me if the cough recurs. |
A 48-year-old man was evaluated for chronic cough "for the past three months."
He gave a history of 'sinus infections' yearly for several years, but said
"this is the worst." He had already had two courses of antibiotics, each for 10 days,
with no improvement. He had not been prescribed prednisone.
I put him on an aggressive course of therapy, and told him if he was no better in a week, that I would do a CT of the sinsuses and perhaps refer him to an ENT surgeon. I stared him on antibiotic Levaquin 500 mg a day, plus prednisone at 20 mg twice a day for a full week. I also gave him a nasal steroid medication to use daily (Flonase), AND a decongestant to use in case there was an allergic component (Claritin-24). He returned the following week minimally improved. As planned, I sent him for a sinus CT scan. The scan showed impacted maxillary sinuses with 'air-fluid' levels, indicating severe chronic sinusitis, plus extensive mucus in his sphenoid and ethmoid sinuses. There sinuses were so blocked that antibiotics and steroids and decongestants simply could not be effective. He was sent to an ENT surgeon who recommeneded surgery to relieve the blocked sinuses. |
For more information on sinus surgery see
When should surgery be considered?
The most common type of surgery is probably endoscopic surgery for maxillary sinusitis (the sinuses behind the cheek bones). One surgeon acknowledged that "a significant number of patients have persistent maxillary symptoms after one or more endoscopic sinus operations," and identified 10 different reasons (see Top 10 reasons for endoscopic maxillary sinus surgery failure, by WJ Richtsmeier. Laryngoscope 2001;111:1952-56.)
Web Links & References / Table of Drugs used to treat rhinitis & sinusitis / 10 Common Myths, Misconceptions, Errors and Mistakes about Chronic Cough / Chronic throat clearing