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Disease Summaries

Rhinosinusitis: Synopsis

Posted: September 2004

Professor Michael A. Kaliner, MD FAAAAI
Medical Director, Institute for Asthma and Allergy
Chevy Chase and Wheaton, Maryland
Professor of Medicine, George Washington University School of Medicine
Washington DC

Definition of Rhinosinusitis

Sinusitis is an inflammatory process that involves one or more of the four paired paranasal sinuses. Because of the contiguous anatomical relationships of the sinuses to the nasal mucosa, it is rare to find inflammation of the sinuses without nasal mucosal involvement, and a more appropriate term for the condition is rhinosinusitis. The maxillary sinuses lie below the eyes in the cheeks, the ethmoid sinuses are between the eyes, the frontal sinuses are above the eyes, and the sphenoid sinuses are postero-medial to the eyes. The sinuses communicate with the nose through small 2mm 5mm openings, the ostia; in the absence of inflammation the sinuses are ventilated with each breath. The sinuses are lined with the same type of mucous membrane that lines the whole respiratory tract, a pseudostratified columnar epithelium with submucous glands and goblet cells. Ciliary flow constantly moves mucus along the walls of the sinus to and through the ostia, and then towards the back of the nose.

Rhinosinusitis may be caused by a variety of underlying conditions, including viral, bacterial or fungal growth, or may be due to a self-perpetuating inflammatory process.


Acute rhinosinusitis: Inflammation of the sinuses, with accompanying symptoms, lasting for less than 4 weeks in adults and children.

Acute recurrent rhinosinusitis: Repeated acute rhinosinusitis episodes occurring four or more times per year, for two or more years.

Subacute rhinosinusitis: Persistent minimal to moderate symptoms of sinus inflammation, often lasting for 4-12 weeks.

Chronic rhinosinusitis: Signs and symptoms of inflammation of the sinuses persisting more than 8 to 12 weeks. The role of bacterial infection in chronic sinusitis is less clear than in acute rhinosinusitis, and chronic rhinosinusitis is more typical of an inflammatory disorder.

Symptoms of Rhinosinusitis

Symptoms of rhinosinusitis include

  • nasal congestion, or blockage,
  • large quantities of green (purulent) mucus which may be blown from the nose, or run down the back of the throat
  • cough
  • sensation of pain and fullness over the affected sinus
  • fever

Nasal mucus is a complex mixture of proteins such as lysozyme which kill potentially harmful bacteria. It also contains antibodies secreted by the mucus-producing glands which kill viruses and bacteria.

Mucus is made every day by the nose and sinuses. Normal mucus is clear or light yellow. Infections cause mucus to thicken and darken. During an upper respiratory tract infection, mucus becomes dark yellow. With bacterial infections, which occur in rhinosinusitis, the mucus becomes green or dark gray. This color reflects the presence of many neutrophils as well as the bacteria growing in the mucus. Bacteria growing in mucus may cause a rank smell, which may be indicative of the presence of gram negative bacteria such as E. coli or Pseudomonas, requiring treatment with appropriate antibiotics.

Causes of Rhinosinusitis

Acute rhinosinusitis commonly begins with a cold, which acutely obstructs the sinus outflow track because of mucosal swelling, followed by a bacterial sinus infection. The area becomes infiltrated by neutrophils, as the mucus glands start to secrete copious amounts of mucus, filling the cavity with inflammatory secretions. Resultant symptoms include nasal congestion, fever, drainage of green purulent mucus and pain and pressure over the infected sinus.

In chronic rhinosinusitis a chronic bacterial or fungal infection of the sinuses is often superimposed upon a self-perpetuating, eosinophil-rich inflammatory process in the sinuses.

Other common conditions which can cause rhinosinusitis

  • Allergic and non-allergic rhinitis
  • Anatomical abnormalities in the nose: eg, nasal septal defects, variations in sinus and nasal development, size and location of middle turbinate
  • Nasal polyps, which should be suspected when the patient describes persistent nasal congestion and loss of sense of smell.
  • Aspirin sensitivity, which may be suggested when patients present with co-existing asthma, moderate blood eosinophilia, non-allergic and/or allergic rhinitis, chronic rhinosinusitis and nasal polyps
  • Immune system deficiencies lack or inadequacy of immunoglobulins/antibodies 
  • AIDS

Less common conditions which cause or are associated with rhinosinusitis

  • Cystic fibrosis
  • Bronchiectasis
  • Cocaine abuse
  • Rhinitis medicamentosa (rhinitis caused by overuse of nasal decongestants)
  • Ciliary dyskinesia, Kartagener's syndrome, Young's syndrome
  • Wegener's granulomatosis

Co-existence of rhinosinusitus with other allergic diseases

Asthma is found in 20-35% of patients with chronic rhinosinusitis. Rhinosinusitis is found in up to 75% of moderate-to severe asthmatics. A study of 200 consecutive cases of chronic rhinosinusitis found allergic rhinitis in 56% of patients.

How Is Rhinosinusitis Diagnosed?

History of symptoms

  • A cold lasting more than 10 days, especially if green secretions are present.
  • Painful, full sensation over affected sinus, headache
  • Fever
  • Large quantities of mucus running down the throat, or blown from the nose

Physical findings

  • Presence of purulent secretions, either as frank pus under the middle turbinate or as strands of green mucus bridging the space between the turbinate and the nasal septum, on anterior or posterior rhinoscopy.
  • Red pharynx
  • Diagnosis is usually made on a presumptive basis supported by history, physical findings, and rhinoscopy, and therapy is initiated. If symptoms fail to respond to initial treatment, or worsen, a standard 4 view sinus x-ray series may be taken ; however, a limited-cut, coronal plane computerised tomography (CT) scan of the sinuses is the recommended test to confirm the diagnosis of rhinosinusitis before different or additional therapy is initiated.

Allergic fungal rhinosinusitis is generally diagnosed by

  • Presence of nasal polyps
  • Allergic mucin
  • Chronic rhinosinusitis evidenced by CT scan
  • Positive fungal culture or histology
  • Allergy to fungi by history, skin prick test or serology.

Rhinosinusitis related to immune deficiency states

Rhinosinusitis is often the presenting disease in patients who fail to make an adequate antibody response to bacterial infections, and screening for total IgG, IgA and IgM should be considered, particularly when rhinosinusitis is combined with otitis, bronchitis, or bronchiectasis. Evaluation of the patient's ability to mount an antibody response to bacteria can be tested by immunization with Streptococcus pneumoniae vaccine, Haemophilus influenzae B conjugated to protein, and/or tetanus toxoid, and measurement of antibody response following immunization. On rare occasions further tests of cellular immunity are indicated.

Treatment of Rhinosinusitis

Acute rhinosinusitis

  • Antibiotics until the patient is well, plus an additional seven days' treatment. Common pathogens are Streptococcus pneumonia, Haemophilus influenzae, Moraxella catarrhalis. Staphylococcus and Streptococcus species. Pseudomonas and E. coli may also be isolated. About 7% of isolates are anaerobic.
  • Decongestant twice daily for 3-7 days, applied into the nose or taken by mouth, to open and drain the sinuses
  • Oral hydration patient recommended to drink 6 to 8 full glasses of water a day to aid mucus flow
  • Nasal washes with saline solution to clear secretions and open the ostia
  • For patients with allergic rhinitis, a second-generation, non-sedating antihistamine may be included to reduce symptoms
  • Many specialists use nasal corticosteroids as part of the treatment of acute rhinosinusitis to help reduce nasal swelling and facilitate drainage from the sinuses
  • Surgery: in selected cases of severe acute rhinosinusitis which have not responded to repeated appropriate medical therapy, endoscopic surgery to remove obstructive nasal mucosa, damaged bone, mucus and pus may be recommended. Procedures may range from a limited opening of a maxillary sinus ostium to resection of the ethmoid air cells and removal of disease from the frontal and sphenoid sinuses.

Chronic rhinosinusitis

  • Antibiotics for a longer period of time (3-6 weeks)
  • Nasal decongestant twice daily for 7-14 days
  • Topical nasal corticosteroid to prevent rhinitis medicamentosa from developing from the use of the decongestant and to keep the sinus outflow track open to prevent recurrence of disease
  • Oral hydration
  • Nasal washes
  • Surgery might be considered in resistant cases after adequate medical therapy has been tried

Allergic fungal rhinosinusitis

  • Functional endoscopic sinus surgery
  • Oral and topical corticosteroids
  • Medical antifungal treatment is indicated for invasive fungal rhinosinusitis

Aspirin sensitivity

Aspirin sensitivity is associated with abnormal production of leukotrienes and a trial of leukotriene modifiers may be warranted.

Immune deficiency

Intravenous gamma globulin replacement is indicated for patients whose total IgG is less than two standard deviations below the normal values for age and geographic location and who cannot make an adequate antibody response to immunizations.

Differential Diagnosis: Allergic rhinitis, rhinosinusitis, viral rhinitis (common cold)

  Rhinosinusitis Viral Rhinitis Allergic Rhinitis
Symptoms Congestion

Green or gray nasal discharge

Postnasal drip

Pressure in the face


Runny nose with watery to thick yellow discharge

Low grade fever


Weakness and fatigue

Runny nose with thin, watery discharge



Itchy nose, throat and eyes
Onset Develops as a complication after a cold. Can also be triggered by allergies. Symptoms develop within one to three days of exposure to the cold virus. Symptoms begin almost immediately after exposure to allergen(s). If seasonal allergies, symptoms occur at the same time every year. If perennial allergies, symptoms are present year-round.
Typical Duration Can last weeks, months and even years if ignored. Five to seven days. Symptoms last as long as you are exposed to the allergen. If the allergen is present year-round, symptoms may be chronic.
Source: American Academy of Allergy Asthma and Immunology



Global figures on the epidemiology of rhinosinusitis are awaited. An example of the importance of rhinosinusitis comes from the United States of America where, in 1993, 14.7% of the population reported suffering from rhinosinusitis. Rhinosinusitis is the third most frequent diagnosis for which antibiotics are prescribed. Figures suggest the total annual direct cost of treatment, including drugs, doctors' office visits and surgery, and indirect costs, including restricted activity days, is in excess of US $6 billion.

Acute rhinosinusitis commonly results from bacterial infection following an upper respiratory tract infection or common cold. One to ten percent of colds in children are followed by a bacterial sinus infection, and children may experience 6-8 colds each year. Estimates suggest that up to 17% of children presenting to physicians for treatment of severe cold symptoms have rhinosinusitis.

The role of environmental factors in the development of rhinosinusitis is not clear. 

Certain occupations, eg, woodworking and carpentry, paint, solvent and dye manufacturing, chemical plants, hazardous waste disposal units, oil and gas distilleries and leather tanning may expose workers to occupational toxins which exacerbate a pre-existing nasal condition and potentiate an inflammatory reaction in the sinuses.

The role of genetic factors in chronic sinus disease is unclear, however two genetic disorders, cystic fibrosis and primary ciliary dyskinesia (Kartagener's syndrome), are associated with persistent sinus disease.

In medical outcomes studies, health related quality of life measures have shown that chronic rhinosinusitis elicits similar responses to other severe chronic illnesses, including congestive heart failure, angina pectoris and chronic obstructive pulmonary disease.