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Sinusitis and Its Story

2010-12-25


What is it?

Sinusitis is inflammation of the sinuses, which are air-filled cavities in the skull. The etiology/causes can be infectious (bacterial, viral, or fungal) or noninfectious (allergic) triggers. This inflammation leads to blockade of the normal sinus drainage pathways, also known as sinus ostia. When sinus ostia is blocked, it leads to mucus retention, deprivation of oxygen supply/hypoxia, decreased mucociliary clearance, and predisposition to bacterial growth.



What causing it?

The most common cause of acute sinusitis is an upper respiratory tract infection (URTI) of viral origin. The viral infection can lead to inflammation of the sinuses that usually resolves without treatment in less than 14 days. If symptoms worsen after 3 to 5 days or persist for longer than 10 days and are more severe than normally experienced with a viral infection, a secondary bacterial infection is diagnosed.

The inflammation can predispose to the development of acute sinusitis by causing sinus ostial blockage. Although inflammation in any of the sinuses can lead to blockade of the sinus ostia, the most commonly involved sinuses in both acute and chronic sinusitis are the maxillary and the anterior ethmoid sinuses.

The nasal mucosa responds to the virus by producing mucus and recruiting mediators of inflammation, such as white blood cells, to the lining of the nose, which cause congestion and swelling of the nasal passages. The resultant sinus cavity hypoxia and mucus retention cause the cilia—which move mucus and debris from the nose—to function less efficiently, creating an environment for bacterial growth.

If the acute sinusitis does not resolve, chronic sinusitis can develop from mucus retention, hypoxia, and blockade of the ostia. This promotes mucosal over production of cells/hyperplasia, continued recruitment of inflammatory infiltrates, and the potential development of nasal polyps.


What a person with sinusitis will have?

Acute bacterial sinusitis in adults most often manifests with more than 7 days of nasal congestion, postnasal drip, and facial pain and pressure, alone or with associated referred pain to the ears and teeth. There may be a cough, often worsening at night.

Children with acute sinusitis might not be able to relay a history of postnasal drainage or headaches, so cough and rhinorrhea(runny nose) are the most commonly reported symptoms. Other symptoms can include fever, nausea, fatigue, impairments of smell and taste, and halitosis (unpleasant odor exhaled in breathing).

Chronic sinusitis can cause more indolent symptoms that persist for months. Nasal congestion and postnasal drainage are the most common symptoms of chronic sinusitis. Chronic cough that is described as worse at night or on awakening in the morning is also a commonly described symptom of chronic sinusitis. Clinical evidence of chronic sinusitis may be subtle and less overt than in acute sinusitis unless the patient is having an acute sinusitis exacerbation (a state of inflammation or painful reaction to allergy or cell-lining damage).


How to treat?

Acute: Antibiotics, such as amoxicillin for 2 weeks, have been the recommended first-line treatment of uncomplicated acute sinusitis. The antibiotic of choice must cover S. pneumoniae, H. influenzae, and M. catarrhalis. Because rare intracranial and orbital complications of acute bacterial sinusitis are caused by S. pneumoniae (most commonly in the immunocompromised host), adequate coverage for this organism is important. Amoxicillin-clavulanate (Augmentin) is also an appropriate first-line treatment of uncomplicated acute sinusitis. The addition of clavulanate, a beta-lactamase inhibitor, provides better coverage for H. influenzae and M. catarrhalis.Because of S. pneumoniae resistance, higher doses of amoxicillin (90 mg/kg/day to a maximum of 2 g/day) should be considered. These higher doses are effective against S. pneumoniae because resistance is related to alteration in penicillin-binding proteins, a mechanism distinct from the beta-lactamase enzymatic inactivation of H. influenzae and M. catarrhalis.

Other options include cephalosporins such as cefpodoxime proxetil (Vantin) and cefuroxime (Ceftin). In patients allergic to beta-lactams, trimethoprim-sulfamethoxazole (Bactrim), clarithromycin (Biaxin), and azithromycin (Zithromax) may be prescribed but might not be adequate coverage for H. influenzae or resistant S. pneumoniae.Penicillin, erythromycin (Suprax), and first-generation cephalosporins such as cephalexin (Keflex, Keftab) are not recommended for treating acute sinusitis because of inadequate antimicrobial coverage of the major organisms.

If treatment with one of these first-line agents has not shown a clinical response within 72 hours of initial therapy, more broad-spectrum antibiotics should be considered. These include the fluoroquinolones, gatifloxacin (Tequin), moxifloxacin (Avelox), and levofloxacin (Levaquin), especially if amoxicillin-clavulanate, cefpodoxime proxetil, and cefuroxime were previously prescribed.


Chronic: Antibiotic therapy for chronic sinusitis is controversial and may be most appropriate for acute exacerbation of chronic sinusitis. Medical therapy should include both a broad-spectrum antibiotic and a topical intranasal steroid to address the strong inflammatory component of this disease. Antibiotic therapy might need to be continued for 4 to 6 weeks.The antibiotics of choice include agents that cover organisms causing acute sinusitis but also cover Staphylococcus species and anaerobes. These include amoxicillin-clavulanate, cefpodoxime proxetil, cefuroxime, gatifloxacin, moxifloxacin, and levofloxacin. Currently used topical intranasal steroids such as fluticasone (Flonase), mometasone (Nasonex), budesonide (Rhinocort AQ), and triamcinolone (Nasacort AQ) have a favorable safety profile and indications for the pediatric age group. A short course of oral steroids may be used for extensive mucosal thickening and congestion or nasal polyps.

Adjunctive Therapy: To temporarily alleviate the drainage and congestion associated with sinusitis, decongestant nasal sprays oxymetazoline (Afrin) and phenylephrine hydrochloride (Neo-Synephrine) may be used for 3 to 5 days. Long-term use of topical decongestants can cause rhinitis medicamentosa, which is rebound congestion caused by vasodilatation and inflammation. Oral decongestants (pseudoephedrine) may be a reasonable alternative if the patient has no contraindication such as hypertension. Mucolytic agents (guaifenesin) can help to decrease the viscosity of the mucus for better clearance and are often found in combination with decongestants. Some mucolytics are now available over the counter. Saline spray or irrigation can help clear secretions. Topical corticosteroids are not indicated for acute sinusitis but may be helpful for chronic sinusitis, nasal polyps, and allergic and nonallergic rhinitis. Antihistamines are not indicated for sinusitis but may be helpful for underlying allergic rhinitis.


Surgery: If medical therapy fails or if complications are suspected, an otolaryngology consultation is warranted. This may begin with a nasal endoscopy for better visualization of the nasal cavity and ostiomeatal complex. The otolaryngologist can also perform endoscopically guided sinus culture. If surgical therapy is being contemplated, newer techniques of functional endoscopic sinus surgery are performed to clear sinuses of chronic infection, inflammation, and polyps. This may be combined with somnoturboplasty (i.e., shrinkage of the turbinate using radiofrequency waves). Endoscopic sinus surgery is commonly performed on an outpatient basis using local anesthesia and has less morbidity than traditional open surgery for chronic sinus disease.

Reference: http://www.clevelandclinicmeded.com/

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