بنام خداوند جان وخرد

Alireza Emami Naeini, MD

Department of Infectious Diseases

Isfahan University of Medical Sciences(IUMS)

Empiric Antibiotic Therapy of Upper and Lower Respiratory Tract

Infections

Pharyngitis

• Bacterial (group A Streptococci)• Membranous, Arcanobacterium ( C.

hemolyiticum). C. diphtheria.• Viral ( EBV, CMV, HHV- 6)• Other ( M. pneumonia, C. pneumonia)

Streptococcal Pharyngitis

• Streptococcal Pharyngitis, Streptococcal Tonsillitis, is a type of Pharyngitis caused by a group A streptococcal infection. It affects the pharynx including the tonsils and possibly the larynx. Common symptoms include: Acute sore throat with fever and bilateral anterior cervical adenopathy.It is the cause of 37% of sore throats among children.

A case

• A 10-year-old girl presents with a sore throat and fever that has lasted for 1 day. She appears flushed and moderately ill. Physical examination reveals a temperature of 39°C, tender bilateral anterior cervical lymph nodes that are 1 to 2 cm in the greatest dimension, and erythema and whitish-yellow exudate over enlarged tonsils and the posterior pharynx. A rapid antigen-detection test from a throat-swab specimen is positive for group A streptococcus.

Antimicrobial Therapy for GAS Pharyngitis

• Penicillin V(10 days)

Children: 250 mg bid or tid

Adolescence and adults: 250 tid or qid or 500 mg bid.

Antimicrobial Therapy for GAS Pharyngitis

• For penicillin allergic patients: - Erythromycin ethylsuccinate ( 20 – 40 mg / kg

divided into 2 to 4 doses) ( maximum 1 g/ day) - First generation cephalosporin's: Cephalexin

250 mg PO qid.

Antimicrobial Therapy for GAS Pharyngitis

• IM Regimens: - Benzathine penicillin G, 600000 U for patients

< 27 kg 1200000 U for patients > 27 kg

PO Therapy

• Amoxicillin q8h x 10 days.• Clindamycin q8h x 10 days.• Clarithromycin XL q 24. 10 days• Azithromycin 500x 1 dose then , then 250 mg

q24 x 4 days.

- Threat within 10 days to prevent ARF.

Bacterial sinusitis

• Acute Bacterial Sinusitis

Acute Bacterial Sinusitis

• Clinical presentation: Nasal discharge and cough frequently with headache, facial pain, and low grade fever lasting > 10-14 days.

• Can also present acutely with high fever (=> ~ 40° C) and purulent nasal discharge ± intense headache lasting for => 3 days.

Diagnostic considerations

• Diagnosis by sinus x- rays or CT or MRI showing complete sinus opacification. Air – fluid levels, mucosal thickening. Consider sinus aspiration in immunocompromized hosts or treatment failure.

• In children , acute sinusitis is a clinical diagnosis, imaging studies are not common.

Oral Antimicrobial agents for Acute Bacterial Sinusitis (Ambulatory)

• Amoxicillin• Pediatric dosage: 40 – 80 mg/ kg/day divided

q12.• Adult dosage: 500 - 875 mg q12h

Oral Antimicrobial agents for Acute Bacterial Sinusitis

• Amoxicillin / clavulanate x 10 days• Doxycicline 200 mg qid x 3 days then 100 q12

Therapeutic considerations

• Macrolides and TMP-SMX may predispose to drug – resistant S. pneumonia (DRSP), and => 30% of S. pneumonia are naturally resistance to macrolides.

Prognosis

• Good if treated for full course. • Relapses may occur with suboptimal

treatment. For frequent recurrences, consider radiologic studies and ENT consultation.

Acute bronchitis

• Acute bronchitis is an inflammation of the large bronchi (medium-size airways) in the lungs that is usually caused by viruses or bacteria and may last several days or weeks

Acute Bronchitis (AB)

• An acute illness, occurring in a patient without chronic lung disease, with symptoms including cough, which may or may not be productive and associated with other symptoms or clinical signs that suggest LRTIs , and no alternative explanation ( e.g. sinusitis or asthma).

• Clinical syndrome distinguished by a relatively brief, self – limited inflammatory process of large and midsized airways, not associated with pneumonia on chest radiograph.

Etiology of AB

• Influenza virus• Rhinovirus• Corona virus• adenovirus• RSV• Human metapneumovirus• Para influenza viruses• S. pneumonia• H. influenza• B. pertussis

*M. Cataralis

Treatment

• Treatment of patients with AB is generally symptomatic and directed at relief of troublesome upper respiratory symptoms, cough and wheezing.

• Therapy directed toward bronchospasm may be required.

• Cough: Narcotic cough suppressants, expectorants, antihistamines, decongestants, β²- agonists(Clobutinol)(Tab 40 mg,drop 60mg/ml)(1-2 tab tid).

Treatment

• In a placebo- controlled double blind trial in experimental rhinovirus infection, the combination of ibuprofen (400mg) plus cholorpheniramine ( 12 mg) administered every 12 hours for 4.5 days, reduced cough significantly.

• IDSA : Do not recommend the routine use of antibiotics for uncomplicated AB in otherwise normal persons.

Antibiotics

• Quinolones ( 5 days)• Amoxicillin – clavulanic acid ( 5 days)• Clarythromycin ( 5 days)• Doxycicline( 5 days) • Azithromycin 500 mg / day ( 3 days)

Pneumonia

Outpatient treatment

Pneumonia

• To the clinician: Pneumonia is a constellation of symptoms and signs ( fever, chills, cough, pleuritic chest pain, sputum production, hyper or hypothermia, increased Respiratory Rate, dullness to percussion, bronchia breathing, egophony, crackle, wheezes, pleural friction rub) in combination with at least one opacity on chest radiography.

Treatment setting; patient condition Regimen• Outpatient ; no

cardiopulmonary disease, no risk factor DRSP infection

• Macrolide(e.g., Clarythromycin 500mg bid PO 10 days; or Azithromycin 500 mg PO once then 250 mg/d 4 days ) or Doxycycline 10 bid PO 10 days

Treatment setting; patient conditionRegimen

• Outpatient; cardiopulmonary disease and/ or risk factors for DRSP infection or (2) high DRSP prevalence in community

• Quinolone with enhanced activity against S. pneumonia- e.g., Levofloxacin 500 mg/ d PO( or, with Ccr < 50 mL/min,250 mg/day), Moxifloxacin 400 mg/d PO or -Lactam( cefpodoxime 200 mg bid, Cefuroxime axetil 750 mg tid, or Amoxicillin 1000mg tid, PO; Amoxicillin /clavulanic acid 875/175 mg / tid plus Macrolide or doxycycline or Telithromycin 800 mg q24 10 days

Treatment setting; patient condition Regimen• Hospital ward • Cefuroxime 750 mg q8h IV

or ceftriaxone 1 g/day IV or cefotaxime 2g q6h IV or ampicillin / sulbactam 1.5- 3 g q6h IV plus Azithromycin 1 g/d IV followed by 500 mg/d IV quinolone with enhanced activity against S. pneumonia.