Sinusitis

Sinusitis
Specialty	Otorhinolaryngology

Sinusitis is an inflammation of the paranasal sinuses, which may or may not be as a result of infection, from bacterial, fungal, viral, allergic or autoimmune issues. Newer classifications of sinusitis refer to it as rhinosinusitis, taking into account the thought that inflammation of the sinuses cannot occur without some inflammation of the nose as well (rhinitis).

Classification

By location

There are several paired paranasal sinuses, including the frontal, ethmoid, maxillary and sphenoid sinuses. The ethmoid sinuses can also be further broken down into anterior and posterior, the division of which is defined as the basal lamella of the middle turbinate. In addition to the acuity of disease, discussed below, sinusitis can be classified by the sinus cavity which it affects:

• Maxillary sinusitis - can cause pain or pressure in the maxillary (cheek) area (e.g., toothache, headache) (J01.0/J32.0)

• Frontal sinusitis - can cause pain or pressure in the frontal sinus cavity (located behind/above eyes), headache (J01.1/J32.1)

• Ethmoid sinusitis - can cause pain or pressure pain between and/or behind eyes, headache (J01.2/J32.2)

• Sphenoid sinusitis - can cause pain or pressure behind the eyes, but often refers to the vertex of the head(J01.3/J32.3)

Recent theories of the sinusitis indicate that it often occurs as part of a spectrum of diseases that affect the respiratory tract (i.e. - the "one airway" theory) and is often linked to asthma. All forms of sinusitis may either result in, or be a part of, a generalized inflammation of the airway so other airway symptoms such as cough may be associated with it. One can get a sinus infection by 'making out' or open mouth kissing.

Acute vs. chronic

Sinusitis can be acute (going on less than four weeks), subacute (4-12 weeks) or chronic (going on for 12 weeks or more).

All three types of sinusitis have similar symptoms, and are thus often difficult to distinguish.

Acute sinusitis

Acute sinusitis is usually precipitated by an earlier upper respiratory tract infection, generally of viral origin. Virally damaged surface tissues are then colonized by bacteria, most commonly Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Staphylococcus aureus. Other bacterial pathogens include other streptococci species, anaerobic bacteria and, less commonly, gram negative bacteria. Another possible cause of sinusitis can be dental problems that affect the maxillary sinus. Acute episodes of sinusitis can also result from fungal invasion. These infections are most often seen in patients with diabetes or other immune deficiencies (such as AIDS or transplant patients on anti-rejection medications) and can be life threatening.

Chronic sinusitis

Chronic sinusitis is a complicated spectrum of diseases that share chronic inflammation of the sinuses in common. The causes are multifactorial and may include allergy, environmental factors such as dust or pollution, bacterial infection, and/or fungus (either allergic, infective or reactive). Non allergic factors such as Vasomotor rhinitis can also cause chronic sinus problems.

Symptoms include: Nasal congestion; facial pain; headache; fever; general malaise; thick green or yellow discharge; feeling of facial 'fullness' worsening on bending over; aching teeth.

Very rarely, chronic sinusitis can lead to Anosmia, the inability to smell or detect odors.

In a small number of cases, chronic maxillary sinusitis can also be brought on by the spreading of bacteria from a dental infection.

Attempts have been made to provide a more consistent nomenclature for subtypes of chronic sinusitis. A task force for the American Academy of Otolaryngology - Head and Neck Surgery / Foundation along with the Sinus and Allergy Health Partnership broke Chronic Sinusitis into two main divisions, Chronic Sinusitis without polyps and Chronic Sinusitis with polyps (also often referred to as Chronic Hyperplastic Sinusitis. Recent studies which have sought to further determine and characterize a common pathologic progression of disease have resulted in an expansion of proposed subtypes. Many patients have demonstrated the presence of eosinophils in the mucous lining of the nose and paranasal sinuses. As such the name Eosinophilic Mucin RhinoSinusitis (EMRS) has come into being. Cases of EMRS may be related to an allergic response, but allergy is often not documentable, resulting in further subcategorization of allergic and non-allergic EMRS.

A more recent, and still debated, development in chronic sinusitis is the role that fungus may play. Fungus can be found in the nasal cavities and sinuses of most patients with sinusitis, but can also be found in healthy people as well. It remains unclear if fungus is a definite factor in the development of chronic sinusitis and if it is, what the difference may be between those who develop the disease and those who do not.

Role of biofilms

It has recently been shown that biofilms are present on the removed tissue of 3/4 of the patients undergoing surgery for chronic sinusitis. The patients with biofilms were shown to have been denuded of cilia and goblet cells. Controls without biofilms had normal cilia and goblet cell morphology. Biofilms were found on samples from two of 10 healthy controls mentioned.

The species of bacteria from interoperative cultures did not correspond to the bacteria species in the biofilm on the respective patient's tissue. In other words: the cultures were negative though the bacteria were present.

Biofilms are up to 1000 times more resistant to some antibiotics than free floating bacteria (biofilm). Antibiotics mentioned as being relatively effective in vitro against Staphylococcus lugdunensis biofilms are tetracycline, linezolid, and moxifloxacin. Nafcillin stimulated biofilm formation. Vancomycin was not effective. However, in another article tetracycline was found to increase the propensity of Pseudomonas aeruginosa to form biofilms and to trigger the type III secretion system and bacterial cytotoxicity. So the same antibiotic that diminishes the tendency of one bacterial species to form a biofilm, increases that tendency in another species. Linezolid was found to inhibit biofilms in both species. Also piliated bacteria such as e. coli, which is considered non-pathogenic normal flora, readily swap plasmids of DNA with other species of bacteria within the biofilm, so if one bacteria in the film has a resistance gene, most of the bacteria in the film may well become resistant.

Chronic sinusitis fits well into the criteria for The Biofilm Paradigm of Infectious Disease. One of the hallmarks of sinusitis is a thick, obstructive, elastic, insoluble mucus; however, normal mucus is produced by goblet cells, and if the biofilm has destroyed the top layer of epithelial cells and with them the cilia and goblet cells, then the heavy mucus can not be a product of errant genetics of goblet cells, or the reaction of the goblet cells to an allergen, because the goblet cells are absent. Thus the thick gooey mucus of chronic sinusitis involving a biofilm apparently must have an origin different from what is normally referred to as mucus. One of the hallmarks of a biofilm is the Extracellular Polymeric substance the bacteria themselves produce on everything from steel to rocks to human tissue. The EPS is a mixture of alginate, proteins , enzymes Polysaccharides and bacterial DNA and is thick, highly adhesive, elastic, and insoluble in water. At present there is no readily available clinical test protocal to differentate allergic musin produced by the patient from biofilm musin produced by bacteria.

These studies looking at removed human tissue suggested that the overwhelming majority of CS surgery patients had a biofilm infection, however there is currently no test protocol to available to the clinician to detect bioflims in patients. Current practice guidelines suggest that if cultures are negative and treatment with antibiotics fails, then the condition is autoimmune, or paradoxically an immune deficient condition.

Sinus headache vs migraine

Headache is rarely a symptom of sinusitis and a "sinus headache" is often a misdiagnosis of a migraine. Acute sinusitis can cause pressure within the sinus cavities of the head, but this always has associated pain to palpation of the sinus area and purulent greenish discharge from the nose. The use of the term sinus headache therefore is often misleading and results in underdiagnosis of migraine. Recent studies indicate that the majority of "sinus headaches" are migraine headache. (Otolaryngol Head Neck Surg. 2005 Oct;133(4):489-96 id = PMID 16213917) (Arch Intern Med. 2004 Sep 13;164(16):1769-72 id = PMID 15364670) This confusion occurs in part because migraine involves activation of the trigeminal nerve in the brain which sends signals to the sinus region through three different nerves - so patients will often feel their migraines in their "sinuses." Since the trigeminal nerve controls the sinus and nose region of the head, a migraine can also cause mucus build up and a "runny nose", which further confuses diagnoses.

It is also possible that chronic sinus inflammation may result in points of contact within the nasal cavity. Some theories involve these contact points as serving as possible triggers for migraine and other types of headache by resulting in increased levels of Substance P. Substance P is a neuropeptide which is involved in the pain response and may cause feedback through the trigeminal nerve system and feed into the migraine response.

Diagnosis

Factors which may predispose to developing sinusitis include: allergies; structural problems such as, for example, a deviated septum, small sinus ostia; smoking; nasal polyps; carrying the cystic fibrosis gene (research is still tentative); prior bouts of sinusitis as each instance may result in increased inflammation of the nasal or sinus mucosa and potentially further narrow the openings.

When imaging techniques are required for diagnosis CT scanning is the method of choice. If allergies are suspected, allergy testing may be performed.

The Unknown 99%

Ruling out bacterial infection as a cause of sinus inflammation is made difficult by the fact that present protocols detect only the 1% or less of bacteria, fungi and actinomycetes that are able to be grown as monocultures. Better culture techniques and DNA and RNA based techniques to detect "unculturable" bacteria have recently become available. The importance of unculturable bacteria in sinusitis and other diseases is unknown and needs further research.[1]

Treatment

Therapeutic measures range from the medicinal to the traditional and may include nasal irrigation or jala neti using a warm saline solution, analgesics (such as aspirin, paracetamol (acetaminophen) or ibuprofen), hot drinks including tea and chicken soup, inhaling steam, over-the-counter decongestants and nasal sprays, and getting plenty of rest. If sinusitis doesn't improve within 48 hours, or is causing significant pain, one should see a doctor, who may prescribe antibiotics or nasal steroids. If the recommended doses and duration of antibiotic treatment(s) are ineffective, one should reconsult a doctor; who may suggest further treatment by a specialist.

For chronic or recurring sinusitis, referral to an otolaryngologist is indicated for more specialist assessment and treatment, which may include nasal surgery.

A relatively recent advance in the treatment of sinusitis is a type of surgery called FESS - functional endoscopic sinus surgery, whereby normal clearance from the sinuses is restored by removing the anatomical and pathological obstructive variations that predispose to sinusitis. This replaces prior open techniques requiring facial or oral incisions and refocuses the technique to the natural openings of the sinuses instead of promoting drainage by gravity, the idea upon which the less effective Caldwell-Luc surgery[2] was based.

Another recently developed treatment is Balloon Sinuplasty™. This method, similar to balloon angioplasty used to "unclog" arteries of the heart, utilizes balloons in an attempt to expand the openings of the sinuses in a less invasive manner. Its final role in the treatment of sinus disease is still under debate but appears promising.

Another treatment option is Coblation which is a recent technique for removing and treating tissue performed at a lower temperatures (40C to 70C). It is patented by ArthoCare.http://www.arthrocareent.com/wt/page/technology

Based on the recent theories on the role that fungus may play in the development of chronic sinusitis, newer medical therapies include topical nasal applications of antifungal agents. Much of the original research indicating fungus took place at the Mayo Clinic and they have since patented this treatment option. Although there are some licensing battles taking place over these drugs as a result of the patent, they are currently available for other uses and therefore can be compounded by pharmacies or even by the patient.

Nasal irrigation and flush promotes sinus cavity health, and patients with chronic sinusitis including symptoms of facial pain, headache, halitosis, cough, anterior rhinorrhea (watery discharge) and nasal congestion found nasal irrigation to be "just as effective at treating these symptoms as the drug therapies." In other studies, "daily hypertonic saline nasal irrigation improves sinus-related quality of life, decreases symptoms, and decreases medication use in patients with frequent sinusitis," and is "recommended as an effective adjunctive treatment of chronic sinonasal symptoms."

Phage therapy: Since the discovery of spontaneous bacterial lysis (from bacteriophages) by Frederick Twort and by Felix d'Herelle, phage therapy (treatment with bacterial viruses) has been used extensively with miscellaneous bacterial infections in the areas of otolaryngology, stomatology, ophthalmology, dermatology, pediatrics, gynecology, surgery (especially against wound infections), urology, and pulmonology. Treatment with phages was developed in the Soviet Union in parallel to the western development of antibotics. Currently phage therapy for chronic Sinusitis is available at the Phage Therapy Center, Tbilisi, Republic of Georgia. [3] or in Poland. [4]

Support Groups

A sinusitis support news group may be found at

http://groups.google.com/group/alt.support.sinusitis/topics?hl=en

References

• Ramadan H, Sanclement J, Thomas J (2005). "Chronic rhinosinusitis and biofilms". Otolaryngol Head Neck Surg. 132 (3): 414–7. PMID 15746854.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Bendouah Z, Barbeau J, Hamad W, Desrosiers M (2006). "Biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa is associated with an unfavorable evolution after surgery for chronic sinusitis and nasal polyposis". Otolaryngol Head Neck Surg. 134 (6): 991–6. PMID 16730544.{{cite journal}}: CS1 maint: multiple names: authors list (link)

Another treatment option is Coblation which is a recent technique for removing and treating tissue performed at a lower temperatures (40C to 70C). It is patented by ArthoCare.

External links

• Sinus Headache - Medterm.com
• Sinus infection - MedicineNet.com.
• Acute sinusitis - MayoClinic.com, from the Web site of the Mayo Clinic.
• Chronic sinusitis - MayoClinic.com, from the Web site of the Mayo Clinic
• NIH
• NHS Direct
• aboutinfections.com information on sinus infections