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 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.

By duration

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. In type I diabetes, ketoacidosis causes sinusitis by Mucormycosis.

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

Biofilms 33 are complex aggregates of extracellular matrix and inter-dependant microorganisms from multiple species, many of which may be difficult or impossible to isolate using standard clinical laboratory techniques. Bacteria found in biofilms may show increased antibiotic resistance when compared to free-living bacteria of the same species. It has been hypothesized that biofilm-type infections may account for many cases of antibiotic-refractory chronic sinusitis. A recent study found that biofilms were present on the mucosa of 3/4 of patients undergoing surgery for chronic sinusitis.

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. 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.

Sinus headaches can be due to vacuum. If the nose is blocked in flight at 33,000 feet, on descent the 15 lb of pressure will cause severe pain localized in the sinus area. Or, any blockage can result in absorption of oxygen and create a vacuum which is very painful. A frequent "sinus headache" is of cervical origin. Usually pain from C2 can refer to the V1 trigeminal root and give rise to "frontal sinus pain", but is due to cervical origin. Migraine differs - it is described as pulsatile, one sided and not localized. Migraine may be hormonal and be started by contraceptive medication in women, often in the same family. Family history is important in diagnosing migraine. Occasionally a bony spur from the nasal septum may impact the side of the nose and give localized or general pain. Histamine cephalgia is another "sinus" location headache. Pain here is extremely severe, one sided, accompanied by tearing one side and nasal congestion. It is not caused by sinus disease.

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.

Several prediction rules have been developed to aid in diagnosis based on the history and physical . The most consistenly identified predictor is the presence of purulent rhinorrhea

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

Treatment

Acute sinusitis

There are over the counter medicines that can relieve some of the symptoms associated with sinusitis. i.e. headaches, pressure, fatigue and pain. Usually these are a combination of some kind of antihistamine along with decongestant or pain reliever. Seeing a doctor will usually result in a prescription for antibiotics and a recommended rest. Furthermore, there have been studies that have concluded allergy testing results in detection of inhaled allergens that lead to inflammation which can trigger sinusitis.

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, a doctor may prescribe antibiotics (Amoxicillin usually being the most common) or nasal steroids.

Chronic sinusitis

Simple measures

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." and irrigation is recommended as an "effective adjunctive treatment of chronic sinonasal symptoms."

Medical approaches

For chronic or recurring sinusitis, referral to an otolaryngologist may be 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 was based.[1]

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.

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.

Other approaches

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 antibiotics. Currently phage therapy for chronic Sinusitis is available at the Phage Therapy Center, Tbilisi, Republic of Georgia,[2] or in Poland.[3]

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)

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
• Sinus Dynamics