Pneumonia PDF

Pneumonia Preapered by:ph:LanaShaker  General overview Pneumonia is the inflammation of lung paranchyma that contain alveoli wich is the functional units of gas exchange …with infiltrate (pus,blood ,protiens) that seen under chest radiograh. Epidemological facts: Pneumonia consider...

Pneumonia Preapered by:ph:LanaShaker  General overview Pneumonia is the inflammation of lung paranchyma that contain alveoli wich is the functional units of gas exchange …with infiltrate (pus,blood ,protiens) that seen under chest radiograh. Epidemological facts: Pneumonia considered the most common cause of death attributable to infectious diseases (very high mortality rate in older adults) and listed in the top 10 causes of death in the United States٫common cause of severe sepsis and of death in children and adults in the United States.about (0.6-1%)of hospitalize patients infected with pneumonia. Classifications of pneumonia 1_Community-acquired pneumonia (CAP) without hospitalization:(mortality rate Less than 1%):occour outside hospital or befor 48 hours befor hospital admission 2_hospital-acquired pneumonia:occour after 48hours after hospital admission (mortality rate About 14%) 3_Ventilator-associated pneumonia (VAP): occour after 48 hours after endotracheal intubation (mortality rate About 20%–50%) 4_aspiration pneumonia  Etiology and Pathophysiology Respiratory pathogens enter the lower respiratory tract by one of three routes: (1) direct inhalation of infectious droplets; (2) aspiration of oropharyngeal contents or (3) hematogenous spread from another infection site. 1- CAP:commonly caused by: A-virauses:(rhinovirus and influenza) B- bacteria:( S. pneumoniae accounting for up to 35%,Other common bacterial causes are H.influenzae, the “atypical” pathogens including M. pneumoniae, Legionella species, C. pneumoniae). 2-HAP:gram-negative aerobic bacilli , S. aureus and is much more likely to be caused by a (multidrug-resistant isolate. P. aeruginosa and Acinetobacter spp). are the most common cause of HAP (about 25%–45%) while K. pneumoniae and E. coli are also common. 3-VAP:MDR non-fermenting gram-negative bacilli, MDR enteric gram negative bacilli, MRSA 4-Aspiration pneumonia:same as CAP and HAP pathogens,also anaerobic pathogens are less common and typically seen in patients with specific risk factors such as periodontal disease or alcoholism. Risk factors 1-Community-acquired pneumonia (CAP):( Age >65 years,Diabetes mellitus,Asplenia,Chronic cardiovascular, pulmonary, renal, and/or liver disease,Smoking and/or alcohol abuse) 2-Hospital-acquired pneumonia: (HAP):(Supine patient position, Enteral feeding,oropharyngeal colonization, Stress ulcer prophylaxis,Blood transfusion ,Hyperglycemia,immunosuppression or corticosteroids,surgical procedures: (thoracoabdominal, upper abdominal, thoracic)surgury Immobilization, Nasogastric tubes,previous antibiotic therapy,Admission to the intensive care unit,Advanced age,Underlying chronic lung disease) 3-VAP: Same as hospital acquired ,MDR risk with IV antibiotics in past 90 days, septic shock, ARDS preceding VAP, acute renal replacement therapy preceding VAP, or 5+ days of hospitalization preceding. 4-aspiration pneumonia: as an enteral feeding tube, gastroesophageal reflux, vomiting, reduced level of consciousness, or impaired swallowing. Clinical presentation Symptoms:Abrupt onset of fever, chills, dyspnea, and productive cough,Rust-colored sputum or hemoptysis; Pleuritic chest pain; and Dyspnea. Signs: _Physical examination findings:1_Tachypnea and tachycardia,Diminished breath sounds over affected area; and Inspiratory crackles during lung expansion. 2_Lab test: reveals Leukocytosis with predominance of polymorphonuclear cells. 3_oxygen saturation on arterial blood gas or pulse oximetry. 4_The chest radiograph and sputum examination and culture are the most useful diagnostic tests for gram-positive and gram-negative bacterial pneumonia _chest radiograph show if there is a dense lobar or lobular consolidated infiltrates Complications of pneumonia Respiratory failure, sepsis, multiorgan failure, coagulopathy, and exacerbation of preexisting comorbidities, pleural effusion, lung abscess, empyema. Goal of Treatment 1_Eradication of the pathogens 2_minimization of of therapy toxicities and induced secondary infections such a clostridium difficile or antibiotic-resistant pathogens And decrease risk of complications. 3_ minimizing costs through outpatient and oral therapy when the patient’s severity of illness permit Evidence-Based Empirical Antimicrobial Therapy for Pneumonia in Adults _For all suspected CAP patients with the exception of COVID-19, , the Infectious Diseases Society of America (IDSA) recommends initial empiric antimicrobial therapy until laboratory results can be obtained more specific therapy. _The causative pathogen in CAP in adult patients is most commonly viral, (human rhinovirus and influenza most common). The most prominent bacterial pathogen causing CAP in otherwise healthy adults is S. pneumoniae accounting for up to 35% of all acute cases. _All asplenic individuals should receive vaccination against Strep. pneumoniae. (RSV and human rhinovirus) predominate in CAP among pediatric Non pharmacological management As (VAP) the most type of pneumonia with highest mortality rate.so it best to avoid through some recommendations: avoiding intubation or re-intubation whenever possible; head of bed elevation(45 centigrade position),hand hygien, spontaneous breathing trials. For Outpatient/Community-acquired pneumonia: 1-No at-risk comorbidity (DM, heart/lung/liver/renal disease, alcoholism, malignancy, asplenia) AND no antimicrobial use in past 3 months: Macrolide: Clarithromycin:0.5–1 g orally once or twice daily Erythromycin:500 mg IV or orally every 6–8 h Azithromycin:500 mg × 1 day (×2 days if parenteral), and then 250 mg days 2–5 IV or orally Or 2-Doxycycline:100 mg IV or orally twice daily 2-patients with risk factors(mentioned previously): a-beta lactam with macrolide OR doxycycline(prefered) (amoxicillin-clavulanate 500 mg/125 mg PO tid or amoxicillin-clavulanate 875 mg/125 mg PO BID or amoxicillin-clavulanate 2000 mg/125 mg) plus a macrolide (azithromycin or clarithromycin) or doxycycline (100 mg PO bid) b-Antipneumococcal fluoroquinolone _cephalosporins can be taken, Cefpodoxime 200 mg PO bid or cefuroxime 500 mg or cefditoren 400 mg PO bid plus a macrolide (azithromycin or clarithromycin) or doxycycline (100 mg PO bid) b-Antipneumococcal fluoroquinolone if beta- lactams cannot be taken: -Levofloxacin 750 mg PO q24h or -Moxifloxacin 400 mg PO q24h or Inpatient/Community-acquired 1-Non-ICU: a-Factors to determine the antibiotic regimen depend on at MRSA or Pseudomonas is present. Risk factors for MRSA or Pseudomonas infection are prior infection with these organisms, particularly(respiratory tract specimen), and recent hospitalization within the past 3 months, with usage of intravenous (IV) antibiotics a-Without suspicion for MRSA or Pseudomonas: 1_Combination of a beta-lactam (ampicillin-sulbactam 2 g IV q6h or ceftriaxone 1-2 g IV q24h or cefotaxime 1-2 g IV q8h or ceftaroline 600 mg IV q12h) plus azithromycin 500 mg IV/PO q24h or doxycycline 100 mg PO BID b-other strong suspicion for pseudomonal infection: Combination therapy with both an antipseudomonal beta-lactam (pipericillin- tazobactam 4.5 g IV q6h or cefepime 2 g IV q8h or ceftazidime 2 g IV q8h or meropenem 500–2000 mg IV every 6 to 8 h or imipenem500–1000 mg IV every 6 to 8 h ) plus an antipseudomonal fluoroquinolone (ciprofloxacin 400 mg IV every 8 h / 750 mg orally twice daily or Levofloxacin 750 mg IV q24h) strong suspicion for MRSA infection: Add vancomycin 15 to 20 mg/kg/dose IV every 8 to 12 hours initially and adjust to therapeutic monitoring or linezolid 600 mg IV every 12 hours Respiratory Tract Infections. -Linezolid is approved for treatment of community-acquired pneumonia due to S. pneumoniae and nosocomial pneumonia due to S. aureus. A randomized clinical trial in patients with MRSA pneumonia demonstrated similar or better outcomes to vancomycin - Because vancomycin penetration into lung tissue is relatively low, aggressive dosing is generally recommended,Telavancin displayed similar efficacy to vancomycin in studies of nosocomial pneumonia due to gram-positive pathogens _ because influenzavirus risk factor for developing MRSA,So During influenza season, it is also reasonable to start antiviral therapy to treat influenza in patients with MRSA CAP,as influenza may have preceded the MRSA infection. 2-ICU: a-No comorbidities/previously healthy; age < 65 years; no recent antibiotic use; no risk factors for MRSA or Pseudomonas aeruginosa: Amoxicillin 1 g tid orAzithromycin 500 mg PO one dose, then 250 mg PO daily orClarithromycin 500 mg PO bid or extended-release 1000 mg PO daily orDoxycycline 100 mg PO bid -ifComorbidities present: Preferred: Combination of a beta-lactam (amoxicillin-clavulanate 500 mg/125 mg PO tid or amoxicillin-clavulanate 875 mg/125 mg PO BID or amoxicillin-clavulanate 2000 mg/125 mg) plus a macrolide (azithromycin or clarithromycin) or doxycycline (100 mg PO bid) Alternatives to the above regimen: If cephalosporins can be taken, Cefpodoxime 200 mg PO bid or cefuroxime 500 mg or cefditoren 400 mg PO bid plus a macrolide (azithromycin or clarithromycin) or doxycycline (100 mg PO bid) or(Levofloxacin 750 mg IV or PO q24h orMoxifloxacin 400 mg IV or PO q24h)... If P. aeruginosa suspected: Antipseudomonal, antipneumococcal β-lactam(piperacillin/tazobactam, cefepime, meropenem, imipenem) + EITHER (1) ciprofloxacin OR (2) levofloxacin OR (3) aminoglycoside +azithromycin OR (4) aminoglycoside + moxifloxacin aminoglycosides:Gentamicin(7.5 mg/kg IV daily),Tobramycin(7.5 mg/kg IV daily),Amikacin(15–20 mg/kg IV daily) _if there is strong suspicion for MRSA infection: Add vancomycin 15 to 20 mg/kg/dose IV every 8 to 12 hours initially and adjust to therapeutic monitoring or linezolid 600 mg IV every 12 hours Respiratory Tract Infections. If influenza suspected: Add oral oseltamivir or intravenous peramivir (when oral medications not possible). Treatment duration: At least 5 days; duration should be guided by a validated measure of clinical stability (resolution of vital sign abnormalities, ability to eat, and normal mentation). For hospital accuired pneumonia 1_Low mortality risk( Indicators of high HAP mortality risk: need for ventilator support due to pneumonia; septic shock.) and No MDR HAP (MDR HAP risk factors: receipt of IV antibiotics in previous 90 days; structural lung disease (bronchiectasis or cystic fibrosis)And risk factors and Local MRSA prevalence