PHARMACOTHERAPY III PHCY 510 University of Nizwa College of Pharmacy and Nursing School of Pharmacy PHARMACOTHERAPY III PHCY 510 Lecture 4 Infectious Diseases “Upper Respiratory Tract Infections” Dr. Sabin Thomas, M. Pharm. Ph. D. Assistant Professor in Pharmacy Practice School of Pharmacy, CPN University of Nizwa

Course Outcome Upon completion of this lecture the students will be able to Describe the Pathophysiology, clinical presentation (signs and symptoms) diagnosis, investigations, treatment strategies, and follow up of Acute Otitis Media, Sinusitis and Pharyngitis. Individualize the antimicrobial treatment for upper respiratory tract infections.

Colds and Flu Viral infection cause rhinitis, pharyngitis and laryngitis (coryzal symptoms). Caused by rhinovirus, coronavirus , adenovirus , influenza and parainfluenza virus. Mild infections called “colds” while severe infections called “flu” Management: symptomatic consists of rest, adequate hydration and simple analgesics antipyretics. Anti‐virals and anti‐bacterials are not indicated

Otitis media Otitis media is an inflammation of the middle ear. Acute otitis media involves rapid onset of signs and symptoms of inflammation in the middle ear that manifests clinically as one or more of following: otalgia (denoted by pulling of the ear in some infants), hearing loss, fever, or irritability. Otitis media with effusion (accumulation of liquid in the middle ear cavity) Differs from acute otitis media where signs and symptoms of an acute infection are absent.

Otitis media is most common in infants and children. Risk factors contributing to increased incidence of otitis media include the winter season, attendance at a daycare center, non breast-feeding in infants, aboriginal or Inuit origin, early age at first infection, nasopharyngeal Colonization with middle ear pathogens.

Pathophysiology Acute bacterial otitis media is due to viral upper respiratory tract infection that causes eustachian tube dysfunction and mucosal swelling in the middle ear. Streptococcus pneumoniae is the most common cause of acute otitis media. Non typable strains of Haemophilus influenzae and Moraxella catarrhalis are responsible. S. pneumoniae isolates are often intermediate to highly resistant to penicillin. Beta-Lactam resistance occurs in about 23% to 35% of H. influenzae and in up to 100% of M. catarrhalis.

Clinical Presentation Signs and symptoms of middle ear infection such as otalgia (ear pain), irritability, and tugging on the ear, accompanied by signs such as a gray, bulging, nonmotile tympanic membrane. These often follow cold symptoms of runny nose, nasal congestion, or cough. Resolution of acute otitis media occurs over 1 week. Pain and fever tend to resolve over 2 to 3 days, with most children becoming asymptomatic at 7 days. Effusions resolve slowly, 90% have disappeared by 3 months.

Treatment Delayed antibiotic treatment (48 to 72 hours) considered in children 6 months to 2 years of age if symptoms are not severe, as it decreases antibiotic adverse effects and minimizes bacterial resistance. Acetaminophen or a nonsteroidal antiinflammatory agent, such as ibuprofen, can be used to relieve pain and malaise in acute otitis media. Amoxicillin is the drug of choice for acute otitis media. High-dose amoxicillin (80 to 90 mg/kg/day) is recommended.

If treatment failure occurs with amoxicillin, an agent should be chosen with activity against b-lactamase–producing H. influenzae and M. catarrhalis as well as drug-resistant S. pneumoniae such as high-dose amoxicillin-clavulanate (recommended), or, cefuroxime, cefdinir, cefpodoxime, cefprozil, or intramuscular ceftriaxone. Vaccination against influenza and pneumococcus may decrease risk of acute otitis media.

Pharyngitis Pharyngitis is an acute infection of the oropharynx or nasopharynx. While viral causes are most common, Group A Βeta–hemolytic Streptococcus, or Streptococcus pyogenes, is the primary bacterial cause. Viruses (such as rhinovirus, coronavirus, and adenovirus) cause most of the cases of acute pharyngitis. Nonsuppurative (inflammation without the production of pus) complications like acute rheumatic fever, acute glomerulonephritis, and reactive arthritis may occur as a result of pharyngitis with Group A Streptococcus.

Clinical Presentation A sore throat of sudden onset that is mostly self-limited. Fever and symptoms resolving in about 3–5 days. Clinical signs and symptoms are similar for viral causes as well as non-streptococcal bacterial causes. Signs and symptoms Sore throat, pain on swallowing, fever. Headache, nausea, vomiting, and abdominal pain (children). Erythema/inflammation of the tonsils and pharynx with or without patchy exudates. Enlarged, tender lymph nodes. Red swollen uvula, petechiae on the soft palate, and a scarlatiniform rash. Lab Test: Throat swab and culture or rapid antigen detection testing.

Treatment Acetaminophen is a better pain management option. Either systemic or topical analgesics can be used, as well as antipyretics and other supportive care including rest, fluids, lozenges, and saltwater gargles. Penicillin is the drug of choice in the treatment of Group A streptococcal pharyngitis. In patients allergic to penicillin, a macrolide such as Erythromycin or a first-generation cephalosporin such as cephalexin. Children should be kept home from daycare or school until afebrile and for the first 24 hours after antimicrobial treatment is initiated after which time transmission is unlikely.

Sinusitis Sinusitis is an inflammation and/or infection of the paranasal sinus mucosa. The term rhinosinusitis is used by some specialists, because sinusitis typically also involves the nasal mucosa. The majority of these infections are viral in origin. Bacterial sinusitis can be categorized into acute and chronic disease. Acute disease lasts less than 30 days with complete resolution of symptoms.

Chronic sinusitis is defined as episodes of inflammation lasting more than 3 months with persistence of respiratory symptoms. Acute bacterial sinusitis is most often caused by the same bacteria implicated in acute otitis media: S. pneumoniae and H. influenzae Chronic sinusitis can be polymicrobial, with an increased prevalence of anaerobes as well as less common pathogens including gram-negative bacilli and fungi.

Clinical Presentation and Diagnosis of Bacterial Sinusitis A nonspecific upper respiratory tract infection that persists beyond 7–14 days. Adults: Nasal discharge/congestion. Maxillary tooth pain, facial or sinus pain that may radiate (unilateral in particular) as well as deterioration after initial improvement. Severe or persistent (beyond 7 days) signs and symptoms are most likely bacterial and should be treated with antimicrobials. Children: Nasal discharge and cough for >10–14 days or severe signs and symptoms like temperature 39°C (102.2°F) or facial swelling or pain are indications for antimicrobial therapy.

Treatment Nasal decongestant sprays such as phenylephrine and oxymetazoline that reduce inflammation by vasoconstriction are often used in sinusitis. Antihistamines should not be used for acute bacterial sinusitis in view of their anticholinergic effects that can dry mucosa and disturb clearance of mucosal secretions. Amoxicillin is first-line treatment for acute bacterial sinusitis for 10 to 14 days, or at least 7 days,