22.11.09

answer to the saudi medical council question examination

Sinusitis, Acute

Brian E Benson, MD,, Attending Physician, Department of Otolaryngology, St Luke's-Roosevelt Hospital Center; Clinical Assistant Professor, Department of Otolaryngology, Hackensack University Medical Center; Director, The Voice Center, Hackensack University Medical Center
Linas Riauba, MD, Assistant Professor of Clinical Medicine, Department of Medicine, Section of Infectious Disease, University Hospital, University of Medicine and Dentistry of New Jersey; Tracey Quail Davidoff, MD, Senior Clinical Instructor, Department of Emergency Medicine, Rochester General Hospital

Updated: Feb 10, 2009
Introduction
Background

Sinusitis is characterized by inflammation of the lining of the paranasal sinuses. Because the nasal mucosa is simultaneously involved and because sinusitis rarely occurs without concurrent rhinitis, rhinosinusitis is now the preferred term for this condition.1 By definition, symptoms of acute rhinosinusitis last less than 3 weeks, symptoms of subacute rhinosinusitis last 21-60 days, and symptoms of chronic rhinosinusitis last more than 60 days. The Agency for Healthcare Research and Quality accepted this terminology in 1999.

Rhinosinusitis may be further classified according to the anatomic site (maxillary, ethmoidal, frontal, sphenoidal), pathogenic organism (viral, bacterial, fungal), presence of complication (orbital, intracranial), and associated factors (nasal polyposis, immunosuppression, anatomic variants).
Pathophysiology

The vast majority of rhinosinusitis episodes are caused by viral infection. Most viral upper respiratory tract infections are caused by rhinovirus, but coronavirus, influenza A and B, parainfluenza, respiratory syncytial virus, adenovirus, and enterovirus are also causative agents.

Almost 90% of patients with upper respiratory tract infections have radiographic evidence of paranasal sinus involvement. However, only 0.5-2% of viral rhinosinusitis cases are complicated by bacterial infection.2

The pathophysiology of rhinosinusitis is related to 3 factors: obstruction of sinus drainage pathways (sinus ostia), ciliary impairment, and mucus quantity and quality.

* Obstruction of the natural sinus ostia prevents normal mucus drainage. Edema, inflammation, polyps, tumors, trauma, scarring, anatomic variants (eg, concha bullosa [pneumatized middle turbinate], septal deviation), and nasal instrumentation (nasogastric tubes or packing) can result in decreased patency of sinus ostia. Hypoxia within the obstructed sinus is thought to cause ciliary dysfunction and alterations in mucus production, further impairing the normal mechanism for mucus clearance.
* Contrary to earlier models of sinus physiology, the drainage patterns of the paranasal sinuses depend not on gravity but on the mucociliary transport mechanism. The metachronous coordination of the ciliated columnar epithelial cells propels the sinus contents toward the natural sinus ostia. Any disruption of the ciliary function results in fluid accumulation within the sinus. Poor ciliary function can result from the loss of ciliated epithelial cells; cold air; high airflow; viral, bacterial, or environmental ciliotoxins; inflammatory mediators; contact between two mucosal surfaces; scars; and primary ciliary dyskinesia (Kartagener syndrome).
* Sinonasal secretions play an important role in the pathophysiology of rhinosinusitis. The mucus that lines the paranasal sinuses is composed of a thin periciliary layer, which enables ciliary mobility, and a thick gel layer, which anchors the tips of the cilia. This mucous blanket contains mucoglycoproteins, immunoglobulins, and inflammatory cells. Alterations in the water content of the mucous blanket can impair ciliary mobility. Overproduction of mucus can overwhelm the mucociliary clearance system, resulting in retained secretions within the sinuses.
* Acute bacterial rhinosinusitis is very frequently associated with viral upper respiratory tract infection, although allergy, trauma, neoplasms, granulomatous and inflammatory diseases, midline destructive disease, environmental factors, dental infection, and anatomic variation, which may impair normal mucociliary clearance, may also predispose to bacterial infection.

Frequency
United States

Rhinosinusitis affects 35 million people per year in the United States and accounts for close to 16 million office visits per year.3 According to the National Ambulatory Medical Care Survey (NAMCS), approximately 14% of adults report having an episode of rhinosinusitis each year, and it is the fifth most common diagnosis for which antibiotics are prescribed. In 1996, Americans spent approximately $3.39 billion treating rhinosinusitis.4

Approximately 0.5-2% of cases of viral rhinosinusitis are complicated by bacterial superinfection.

Sinusitis is more common from early fall to early spring.
Mortality/Morbidity

Forty percent of acute rhinosinusitis cases resolve spontaneously. Untreated or inadequately treated rhinosinusitis may lead to complications such as meningitis, cavernous sinus thrombophlebitis, orbital cellulitis or abscess, and brain abscess.
Race

Acute rhinosinusitis has no racial predilection.
Sex

Acute rhinosinusitis has no sexual predilection.
Age

Sinusitis occurs in all age groups.
Clinical
History

A history of occupational or allergic rhinitis, vasomotor rhinitis, nasal polyps, rhinitis medicamentosa, or immunodeficiency should be sought in an evaluation for rhinosinusitis. Rhinosinusitis is more common in individuals with congenital defects that affect humoral immunity and ciliary motility, in those with cystic fibrosis, and in persons with AIDS. Obtain a history of diabetes or organ transplant if invasive fungal sinusitis is being considered.

Acute bacterial rhinosinusitis is commonly overdiagnosed. In fact, acute bacterial rhinosinusitis is the correct diagnosis in only 40-50% of cases in which a primary care physician initially classifies a patient as likely having the condition.5

The natural history of rhinovirus infection, as described by Gwaltney et al, lasts from 1-33 days. One fourth of patients have symptoms that last longer than 14 days.6

* Patients with uncomplicated upper respiratory tract infections usually report some of the following symptoms: sneezing, rhinorrhea, nasal congestion, hyposmia/anosmia, facial pressure, postnasal drip, sore throat, cough, ear fullness, fever, and myalgia.
* Although diagnostic criteria for acute rhinosinusitis have been proposed,1 no single sign or symptom has strong diagnostic value for bacterial rhinosinusitis.7 However, acute bacterial rhinosinusitis should be suspected in patients who exhibit symptoms of viral upper respiratory tract infection that do not improve after 10 days or that worsen after 5-7 days.
* Symptoms of acute bacterial rhinosinusitis include the following:
o Facial pain or pressure (especially unilateral)
o Hyposmia/anosmia
o Nasal congestion
o Nasal drainage
o Postnasal drip
o Fever
o Cough
o Fatigue
o Maxillary dental pain
o Ear fullness/pressure
* A change in the color or characteristic of the nasal discharge is not a specific sign of bacterial rhinosinusitis.
* A previous diagnosis of rhinosinusitis is not a predictor of acute bacterial rhinosinusitis.7

Physical

* Purulent nasal secretions
* Purulent posterior pharyngeal secretions
* Mucosal erythema
* Periorbital edema
* Tenderness overlying sinuses
* Air-fluid levels on transillumination of the sinuses (60% reproducibility rate for assessing maxillary sinus disease)
* Facial erythema

Causes

The most common pathogens isolated from maxillary sinus cultures in patients with acute bacterial rhinosinusitis include Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Streptococcus pyogenes, Staphylococcus aureus, and anaerobes are less commonly associated with acute bacterial rhinosinusitis.

* S pneumoniae are gram-positive, catalase-negative, facultatively anaerobic cocci that account for 20-43% of acute bacterial rhinosinusitis cases in adults. The rise of antimicrobial resistance in S pneumoniae is a major concern. A 1998 surveillance study of respiratory tract isolates estimated that 12.3% of S pneumoniae isolates obtained from the paranasal sinuses had intermediate resistance to penicillin; 37.4% were penicillin-resistant. The paranasal sinuses represented the anatomic location with the highest resistance rate.8 Resistance to macrolide, clindamycin, trimethoprim-sulfamethoxazole (TMP-SMX), and doxycycline was more common in isolates with intermediate penicillin resistance and those that were penicillin-resistant.
* H influenzae are gram-negative, facultatively anaerobic bacilli. H influenza type B was a leading cause of meningitis until the widespread use of the vaccine. Nontypeable strains of H influenza are responsible for 22-35% of acute bacterial rhinosinusitis cases in adults. M catarrhalis are gram-negative, oxidase-positive, aerobic diplococci. M catarrhalis is the responsible pathogen in 2-10% of acute bacterial rhinosinusitis cases in adults. Beta-lactamase production is the mechanism of antimicrobial resistance for both M catarrhalis and H influenza. Of isolates from the paranasal sinus, 32.7% and 98% were found to be beta-lactamase?positive for H influenza and M catarrhalis, respectively.
* Although accounting for 10% of episodes of acute bacterial rhinosinusitis, S aureus is now recognized as an increasingly common pathogen in acute bacterial rhinosinusitis.9 While methicillin-resistant S aureus (MRSA) still represents a minority of episodes of S aureus rhinosinusitis, increasing trends of drug-resistant S aureus may alter future treatment recommendations.10
* Rarely, sinusitis is caused by fungi, including genera in the order Mucorales and Aspergillus or Candida species. Fungal infections are more common in people with diabetes and those who are immunocompromised. Clinicians should maintain a high index of suspicion for acute invasive fungal sinusitis in immunocompromised patients with orbital or CNS complications of rhinosinusitis.

Differential Diagnoses
Adenoviruses
Mucormycosis
Allergic and Environmental Asthma
Parainfluenza Virus
Asthma
Rhinitis, Allergic
Bronchitis
Rhinocerebral Mucormycosis
Haemophilus Influenzae Infections
Rhinoviruses
Human T-Cell Lymphotrophic Viruses
Sarcoidosis
Immunosuppression
Sinusitis, Chronic
Influenza
Staphylococcal Infections
Kartagener Syndrome
Streptococcus Group A Infections
Lymphoma, B-Cell
Streptococcus Group B Infections
Moraxella Catarrhalis Infections

Other Problems to Be Considered

Gastroesophageal reflux
Cystic fibrosis
Immotile cilia syndrome
Migraine headache
Sinonasal polyposis
Chemical rhinitis
Nasal foreign body
Chronic invasive fungal sinusitis
Sinonasal neoplasm
Workup
Laboratory Studies

* The erythrocyte sedimentation rate and C-reactive protein level may be elevated in rhinosinusitis, but these findings are nonspecific.
* The findings of CBC count with differential may be within reference ranges.
* Nasal cytology examinations may be useful to elucidate the following entities:
o Allergic rhinitis
o Eosinophilia
o Nasal polyposis
o Aspirin sensitivity
* Sweat chloride test screening should be performed if cystic fibrosis is suggested.
* Ciliary function studies help screen for Kartagener syndrome.
* Tests for immunodeficiency are indicated if history findings indicate recurrent infection, to include the following:
o Immunoglobulin studies
o HIV serology
* Cultures of nasal secretions are of limited value because they are usually contaminated by normal flora.

Imaging Studies

* Findings on standard radiography are insensitive, especially for ethmoidal disease. Waters view is best.
* CT scanning is the preferred imaging method for rhinosinusitis.
o A screening sinus CT scan is adequate for diagnosis and less expensive than other methods but is necessary only in cases of treatment failure or chronic rhinosinusitis.
o A complete sinus CT scan with frontal and coronal planes is used if an alternate diagnosis (eg, tumors) must be excluded.
o CT scan findings are used to differentiate orbital cellulitis from periorbital cellulitis as a complication or to evaluate extension into intracranial space.
* MRI is useful only if fungal infection or a tumor is suggested.
* Ultrasonography is of limited use.

Procedures

* Paranasal biopsy is used to help exclude neoplasia, fungal disease, and granulomatous disease.
* Fiberoptic sinus endoscopy is used to visualize posterior sinonasal structures. This test is useful in chronic or recurrent rhinosinusitis and to help exclude structural lesions, fungal disease, and granulomatous diseases.

Treatment
Medical Care

The goals of therapy in rhinosinusitis are to improve mucociliary function and to control infection.
Surgical Care

Antral puncture and irrigation are used for diagnostic culture and sensitivity testing in immunosuppressed or critically ill patients if the organism must be identified. However, more recent data support the role of endoscopically guided middle meatus cultures instead.
Consultations

* Ear, nose, and throat specialist for complications or when routine management techniques fail
* Infectious disease specialist in complicated cases

Medication

Viral rhinosinusitis does not require antimicrobial treatment.

Standard nonantimicrobial treatment options include topical steroids, topical and/or oral decongestants, mucolytics, and intranasal saline spray.

A recent meta-analysis of 4 double-blind, placebo-controlled trials of intranasal corticosteroid treatment in acute rhinosinusitis supports its use as monotherapy or as an adjuvant therapy to antibiotics.11 However, a recent randomized controlled trial of antibiotics and intranasal steroid showed no treatment benefit of intranasal steroids, either alone or with antibiotics.12

Ahovuo-Saloranta et al, in a 2008 Cochrane Review meta-analysis of 57 studies, concluded that antibiotics yield a small treatment effect in a primary care setting in patients with uncomplicated sinusitis whose symptoms have lasted more than 7 days.13 However, another meta-analysis found no treatment effect of antibiotics, even in patients whose symptoms had persisted for more than 10 days.14

No available data suggest that antihistamines are beneficial in acute sinusitis. In fact, antihistamines may cause harm by drying mucous membranes and decreasing clearance of secretions.
Antibiotics

Antibiotic efficacy rates are as follows:

* Levofloxacin, moxifloxacin, and amoxicillin/clavulanate - Greater than 90%
* High-dose amoxicillin, cefpodoxime proxetil, cefixime, cefuroxime axetil, and trimethoprim-sulfamethoxazole - 80-90%
* Clindamycin, doxycycline, cefprozil, azithromycin, clarithromycin, and erythromycin - 70-80%
* Cefaclor and loracarbef - 50-60%

Based on the 2000 Sinus and Allergy Health Partnership treatment guidelines for acute bacterial rhinosinusitis, patients are divided into 3 groups, as follows:

* Adults with mild disease who have not received antibiotics: Amoxicillin/clavulanate, amoxicillin (1.5-3.5 g/d), cefpodoxime proxetil, or cefuroxime is recommended as initial therapy.
* Adults with mild disease who have had antibiotics in the previous 4-6 weeks and adults with moderate disease: Amoxicillin/clavulanate, amoxicillin (3-3.5 g), cefpodoxime proxetil, or cefixime is recommended.
* Adults with moderate disease who have received antibiotics in the previous 4-6 weeks: Amoxicillin/clavulanate, levofloxacin, moxifloxacin, or doxycycline is recommended.

Patients who remain symptomatic despite appropriate antibiotic therapy may be evaluated with sinus endoscopy, CT scanning, or sinus aspiration/culture.

Amoxicillin (Amoxil, Trimox)

First-line antibiotic choice. Interferes with synthesis of cell wall mucopeptides during active multiplication, resulting in bactericidal activity against susceptible bacteria.
Dosing
Adult

250 mg PO q8h for 10-12 d
Pediatric

Not established
Interactions

Reduces efficacy of oral contraceptives
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Adjust dose in renal impairment; use during mononucleosis produces a characteristic rash

Penicillin V potassium (Beepen-VK, Pen-Vee K)

First-line antibiotic choice. Inhibits biosynthesis of cell wall mucopeptide. Bactericidal against sensitive organisms when adequate concentrations are reached and most effective during stage of active multiplication. Inadequate concentrations may produce only bacteriostatic effects.
Dosing
Adult

250 mg PO q6h for 10-12 d
Pediatric

Not established
Interactions

Probenecid may increase effectiveness by decreasing clearance; tetracyclines are bacteriostatic, causing a decrease in effectiveness when administered concurrently
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Caution in renal impairment; superinfections may occur with prolonged use; reduces efficacy of oral contraceptives

Erythromycin (E.E.S., E-Mycin, Eryc)

First-line treatment in patients allergic to penicillin. Inhibits bacterial growth, possibly by blocking dissociation of peptidyl t-RNA from ribosomes, causing RNA-dependent protein synthesis to arrest.
Dosing
Adult

250 mg PO q6h for 10-12 d
Pediatric

Not established
Interactions

Coadministration may increase toxicity of theophylline, digoxin, carbamazepine, benzodiazepines, and cyclosporine; may potentiate anticoagulant effects of warfarin; coadministration with lovastatin and simvastatin increases risk of rhabdomyolysis; may prolong QT interval, resulting in cardiac arrest if combined with nonsedating antihistamines
Contraindications

Documented hypersensitivity; hepatic impairment
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Caution in liver disease; estolate formulation may cause cholestatic jaundice; adverse GI effects are common (give doses pc); discontinue use if nausea, vomiting, malaise, abdominal colic, or fever occur

Trimethoprim and sulfamethoxazole (Bactrim DS, Septra)

First-line agent with more convenient dosing. Inhibits bacterial growth by inhibiting synthesis of dihydrofolic acid.
Dosing
Adult

160 mg TMP/800 mg SMZ PO q12h for 10-12 d
Pediatric

<2 months: Do not administer
>2 months: Not established
Interactions

May increase PT when used with warfarin (perform coagulation tests, and adjust dose accordingly); coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly persons; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine
Contraindications

Documented hypersensitivity; megaloblastic anemia due to folate deficiency
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Discontinue at first appearance of skin rash or sign of adverse reaction; obtain CBC counts frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, give 5-15 mg/d leucovorin); caution in folate deficiency (eg, people with long-term alcoholism, elderly people, those receiving anticonvulsant therapy, those with malabsorption syndrome); hemolysis may occur in G-6-PD deficiency; patients with AIDS may not tolerate or respond to TMP-SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); give fluids to prevent crystalluria and stone formation

Cefprozil (Cefzil)

Second-line agent. Binds to one or more of the penicillin-binding proteins, which, in turn, inhibits cell wall synthesis and results in bactericidal activity.
Dosing
Adult

250-500 mg PO q12h for 10 d
Pediatric

Not established
Interactions

Probenecid increases effect; coadministration with furosemide and aminoglycosides increases nephrotoxic effects
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Adjust dose in severe renal insufficiency (high doses may cause CNS toxicity); superinfections and promotion of nonsusceptible organisms may occur with prolonged use or repeated therapy

Cefuroxime (Ceftin)

Second-line agent. Second-generation cephalosporin maintains gram-positive activity of first-generation cephalosporins. Adds activity against Proteus mirabilis, H influenzae, Escherichia coli, Klebsiella pneumoniae, and M catarrhalis.
Dosing
Adult

250 mg PO bid for 10 d
Pediatric

Not established
Interactions

Disulfiramlike reactions may occur when alcohol is consumed within 72 h after taking cefuroxime; may increase hypoprothrombinemic effects of anticoagulants; may increase nephrotoxicity in patients receiving potent diuretics such as loop diuretics; coadministration with aminoglycosides increases nephrotoxic potential; concomitant use with agents that lower gastric pH decreases absorption
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Reduce dosage by half if CrCl is 10-30 mL/min and by three fourths if <10 mL/min (high doses may cause CNS toxicity); bacterial or fungal overgrowth of nonsusceptible organisms may occur with prolonged or repeated therapy

Cefpodoxime (Vantin)

Second-line agent. Binds to one or more penicillin-binding proteins, which, in turn, inhibits cell wall synthesis and results in bactericidal activity.
Dosing
Adult

100 mg PO q12h for 10 d
Pediatric

Not established
Interactions

Probenecid increases effect; coadministration with furosemide and aminoglycosides increases nephrotoxic effects; antacids and H2 blockers decrease absorption
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Reduce dosage by half if CrCl is 10-30 mL/min and by three fourths if <10 mL/min (high doses may cause CNS toxicity); bacterial or fungal overgrowth of nonsusceptible organisms may occur with prolonged or repeated therapy

Cefixime (Suprax)

Second-line agent. By binding to one or more penicillin-binding proteins, arrests bacterial cell wall synthesis and inhibits bacterial growth.
Dosing
Adult

400 mg PO qd for 10 d
Pediatric

Not established
Interactions

Increases carbamazepine levels; coadministration of aminoglycosides increases nephrotoxicity; probenecid may increase effects
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Adjust dose in severe renal insufficiency (high doses may cause CNS toxicity); superinfections and promotion of nonsusceptible organisms may occur with prolonged use or repeated therapy

Amoxicillin and clavulanate (Augmentin)

Second-line agent. Drug combination treats bacteria resistant to beta-lactam antibiotics.
Dosing
Adult

875 mg PO q12h or 500 mg PO q8h for 10 d
Pediatric

Not established
Interactions

Coadministration with warfarin or heparin increases risk of bleeding
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

Presence of mononucleosis produces skin rash; interstitial nephritis and renal failure may occur in high doses

Clarithromycin (Biaxin)

Second-line agent. Inhibits bacterial growth, possibly by blocking dissociation of peptidyl t-RNA from ribosomes, causing RNA-dependent protein synthesis to arrest.
Dosing
Adult

500 mg PO bid for 10 d
Pediatric

Not established
Interactions

Toxicity increases with coadministration of fluconazole, astemizole, and pimozide; effects decrease and adverse GI effects may increase with coadministration of rifabutin or rifampin; may increase toxicity of anticoagulants, cyclosporine, tacrolimus, digoxin, omeprazole, carbamazepine, ergot alkaloids, triazolam, and HMG CoA-reductase inhibitors; serious cardiac arrhythmia may occur with coadministration of cisapride; plasma levels of certain benzodiazepines may increase, prolonging CNS depression; arrhythmia and increase in QT intervals occur with disopyramide; coadministration with omeprazole may increase plasma levels of both agents
Contraindications

Documented hypersensitivity; coadministration of pimozide or cisapride
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Coadministration with ranitidine or bismuth citrate is not recommended with CrCl <25 mL/min; give half dose or increase dosing interval if CrCl <30 mL/min; diarrhea may be sign of pseudomembranous colitis; superinfections may occur with prolonged or repeated antibiotic therapies

Levofloxacin (Levaquin)

Used to treat acute maxillary sinusitis caused by S pneumoniae, H influenzae, or M catarrhalis. Fluoroquinolones should be used empirically in patients likely to develop exacerbation due to resistant organisms to other antibiotics. This is the L stereoisomer of the D/L parent compound ofloxacin, the D form being inactive. Good monotherapy with extended coverage against Pseudomonas species, as well as excellent activity against pneumococcus. Agent acts by inhibition of DNA gyrase activity. PO form has bioavailability that is reportedly 99%.
Dosing
Adult

500 mg PO qd for 7-14 d
Pediatric

<18 years: Not recommended
>18 years: Administer as in adults
Interactions

Antacids, iron salts, and zinc salts may reduce serum levels; administer antacids 2-4 h before or after taking fluoroquinolones; cimetidine may interfere with metabolism of fluoroquinolones; reduces therapeutic effects of phenytoin; probenecid may increase serum concentrations; may increase toxicity of theophylline, caffeine, cyclosporine, and digoxin (monitor digoxin levels); may increase effects of anticoagulants (monitor PT)
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

In prolonged therapy, perform periodic evaluations of organ system functions (eg, renal, hepatic, hematopoietic); adjust dose in renal function impairment; superinfections may occur with prolonged or repeated antibiotic therapy

Doxycycline (Periostat, Doryx, Bio-Tab, Vibramycin Vibra-tabs)

Inhibits protein synthesis, and thus bacterial growth, by binding to 30S and possibly 50S ribosomal subunits of susceptible bacteria.
Dosing
Adult

100-200 mg PO bid for 14 d
Pediatric

<8 years: Not recommended
>8 years: 2-5 mg/kg/d PO in 1-2 divided doses; not to exceed 200 mg/d
Interactions

Bioavailability decreases with antacids that contain aluminum, calcium, magnesium, iron, or bismuth subsalicylate; tetracyclines can increase hypoprothrombinemic effects of anticoagulants; tetracyclines can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy
Contraindications

Documented hypersensitivity; severe hepatic dysfunction
Precautions
Pregnancy

D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Precautions

Photosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; tetracycline use during tooth development (last half of pregnancy through age 8 y) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines
Topical decongestants

These agents cause vasoconstriction, which reduces nasal congestion.

Phenylephrine (Neo-Synephrine)

Produces vasoconstriction. Possibly helpful, not harmful.
Dosing
Adult

2 puffs q4h prn; not to exceed 3 d of use
Pediatric

Not established
Interactions

May cause hypertensive crisis in the presence of MAOIs
Contraindications

Documented hypersensitivity; severe hypertension or ventricular tachycardia
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Prolonged use may produce rhinitis medicamentosa; caution in hypertension

Oxymetazoline (Afrin)

Applied directly to mucous membranes. Stimulates alpha-adrenergic receptors and causes vasoconstriction. Decongestion occurs without drastic changes in blood pressure, vascular redistribution, or cardiac stimulation.
Dosing
Adult

2 puffs in each nostril bid; not to exceed 3 d of use
Pediatric

Not established
Interactions

Hypotensive action of guanethidine may be reversed; concurrent administration with methyldopa may result in increased vasopressor response; concurrent use of MAOIs and ephedrine may result in hypertensive crisis; pressor sensitivity to mixed-acting agents, such as ephedrine, may be increased; guanethidine potentiates effects of epinephrine and inhibits effects of ephedrine; phenothiazines may reverse action of nasal decongestants; TCAs potentiate vasopressor response and may result in dysrhythmia
Contraindications

Documented hypersensitivity; MAOI therapy; angle-closure glaucoma
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Caution in hyperthyroidism, coronary artery and ischemic heart disease, diabetes mellitus, increased intraocular pressure, or prostatic hypertrophy; because of increase in vasoconstriction, patients who are hypertensive may experience change in blood pressure; may produce rhinitis medicamentosa

Guaifenesin (Anti-Tuss, Humibid LA, Robitussin)

Increases respiratory tract fluid secretions and helps to loosen phlegm and bronchial secretions. Indicated for patients with bronchiectasis complicated by tenacious mucous and/or mucous plugs.
Dosing
Adult

600-mg SR tab 1-2 tab PO q12h
Pediatric

<2 years: Not recommended
2-6 years: One-half tab PO q12h
6-12 years: 1 tab q12h
>12 years: Administer as in adults
Interactions

May increase renal clearance of urate and lower serum uric acid levels
May interfere with urine laboratory tests for 5-hydroxyindoleacetic acid and urine testing for catecholamines
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions

When prescribing medication that may suppress cough, important to identify cause of the cough and that suppression will not increase risk of clinical or physiologic complications
Corticosteroids: Topical decongestants

These agents are beneficial, especially if underlying rhinitis is present.

Beclomethasone (Beconase, Vancenase)

Has potent vasoconstrictive and anti-inflammatory activity. Has a weak hypothalamic-pituitary-adrenocortical (HPA) axis inhibitory potency when applied topically.
Dosing
Adult

2 puffs in each nostril bid for 3 wk
Pediatric

Not established
Interactions

None reported
Contraindications

Documented hypersensitivity; viral, fungal, and bacterial skin infections
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Prolonged use may increase systemic absorption of corticosteroids and may cause Cushing syndrome, reversible HPA axis suppression, hyperglycemia, and glycosuria; nasal septum perforation, angioedema, and bronchospasm may occur

Triamcinolone (Nasacort, Nasacort AQ)

Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing capillary permeability.
Dosing
Adult

2 puffs in each nostril qd
Pediatric

Not established
Interactions

None reported
Contraindications

Documented hypersensitivity; fungal, viral, and bacterial skin infections
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Prolonged use can result in systemic absorption, which may cause Cushing syndrome, reversible HPA axis suppression, hyperglycemia, and glycosuria; nasal septum perforation, angioedema, or bronchospasm may occur

Flunisolide (AeroBid, Nasalide)

Inhibits bronchoconstriction mechanisms. Produces direct smooth muscle relaxation. May decrease number and activity of inflammatory cells, in turn decreasing airway hyperresponsiveness.
Decreases inflammation by suppressing migration of polymorphonuclear leukocytes and reversing capillary permeability. Does not depress the hypothalamus.
Dosing
Adult

2 sprays/nostril bid/tid (25 mcg/spray)
Pediatric

<6 years: Not established
>6 years: 1 spray/nostril tid or 2 sprays/nostril bid (25 mcg/spray)
Interactions

None reported
Contraindications

Documented hypersensitivity
Precautions
Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions

Educate patient that this agent is not to be used as a rescue treatment for acute bronchospasm
Follow-up
Further Outpatient Care

* Symptomatic or adjunctive therapies may include the following:
o Humidification/vaporizer
o Warm compresses
o Adequate hydration
o Smoking cessation
o Balanced nutrition
o Nonnarcotic analgesia
* Antihistamines are not recommended and have not been proven beneficial.

Complications

* Treatment fails in 10-25% of patients. If this occurs, consider the following:
o Take a repeat history and perform an additional physical examination; consider an imaging study.
o Start second-line antibiotics.
* Approximately 75% of orbital or periorbital infections are the result of extending sinusitis.
* Untreated, inadequately treated, or partially treated rhinosinusitis may lead to chronic rhinosinusitis, meningitis, brain abscess, or other extra-sinus complications.

Prognosis

* Approximately 40% of acute sinusitis cases resolve spontaneously without antibiotics.
* The relapse rate after successful treatment is less than 5%.

Miscellaneous
Medicolegal Pitfalls

* Failure to recognize and aggressively evaluate and treat in light of the following concurrent diagnoses:
o HIV infection/AIDS
o Diabetes
o Hematologic malignancy
o Immunocompromise
* Failure to recognize complications
http://emedicine.medscape.com/article/232670-print

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