Community Acquired Pneumonia, Bronchiectasis and Lung Abscess PDF

COMMUNITY ACQUIRED PNEUMONIA, BRONCHIECTASIS AND LUNG ABSCESS MARY VIOLET B. ZALDARRIAGA, MD, FPCP, FPCCP CPU COLLEGE OF MEDICINE BSRT SEPTEMBER 17, 2024  OBJECTIVES What is Community Acquired Pneumonia (CAP)? What is Bronchiect...

COMMUNITY ACQUIRED PNEUMONIA, BRONCHIECTASIS AND LUNG ABSCESS MARY VIOLET B. ZALDARRIAGA, MD, FPCP, FPCCP CPU COLLEGE OF MEDICINE BSRT SEPTEMBER 17, 2024  OBJECTIVES What is Community Acquired Pneumonia (CAP)? What is Bronchiectasis? What is Lung Abscess? Diagnosis and Management of above Respiratory illnesses  COMMUNITY ACQUIRED PNEUMONIA An infection of the pulmonary parenchyma Remains the leading cause of death worldwide 6th leading cause of death overall and a major cause of morbidity and mortality  PNEUMONIA results from the proliferation of microbial pathogens at the alveolar level and the host’s response to those pathogens Access of microorganism to lower respiratory tract: Aspiration from oropharynx-most common Hematogenous spread Contiguous extension from infected pleural or mediastinal space  PNEUMONIA Mechanical factors are important in host Resident alveolar macrophages response Clears and kills pathogen hairs and turbinates of the nares Branching architecture of Tracheobronchial tree Gag and cough reflex Normal flora that adheres to mucosal cells of oropharynx  PATHOPHYSIOLOGY IL1 and TNF – Fever Dyspnea from IL8 and GCSF – peripheral leukocytosis and Decreased compliance from capillary leak Increased purulent secretions Hypoxemia Inflammatory mediators and neutrophils- Increased respiratory drive Capillary leak: infiltrate on xray/ rales on auscultation Increased secretions Erythrocytes – hemoptysis Infection-related bronchospasm Alveolar filling – hypoxemia Increased Respiratory drive in SIRS - Respiratory Alkalosis  PATHOLOGY Edema Phase- bacteria + neutrophil Red Hepatization- rbc Gray Hepatization- neutrophil Resolution- macrophages  RISK FACTORS FOR CAP Alcoholism Asthma Immunosuppression Institutionalization Age of greater than or equal to 70 years old  CLINICAL DIAGNOSIS OF CAP Can CAP be diagnosed accurately by history and physical examination? The accuracy of predicting CAP by physicians’ clinical judgment is between 60-76%. (Grade B), clinical prediction rules combining history and physical examination findings may be utilized to presumptively identify patients with pneumonia. (Grade B) Is there any clinical feature that can predict CAP caused by an atypical pathogen? There is no clinical feature that can reliably distinguish pneumonia due to a typical or an atypical pathogen. (Grade A)  CLINICAL MANIFESTATIONS OF CAP Fever with tachycardia Cough with or without hemoptysis History of chills and or sweat Short of breath Pleuritic chest pain Gastrointestinal symptoms Fatigue, headache, myalgia, arthralgia  DIFFERENTIAL DIAGNOSIS FOR CAP Acute Bronchitis Acute exacerbation of chronic bronchitis Heart failure Pulmonary Embolism Hypersensitivity Pneumonitis Radiation Pneumonitis  ETIOLOGIC DIAGNOSIS Gram’s stain and Culture – yield is less than or equal to 50% Blood Culture – yield is 5-14% Urinary Antigen Tests: Legionella Urine Antigen Test: Sensitivity- 70%, specificity 99% Pneumococcal Urine Antigen Test: Sensitivity 70%, specificity is more than 90% Serology test : fourfold rise in IgM titer between acute and convalescent phase is diagnostic of infection Biomarkers CRP – identify worsening disease or treatment failure Procalcitonin – distinguish viral from bacterial infection, to initiate antibacterial therapy or when to discontinue treatment  CHEST XRAY What is the value of the chest radiograph in the diagnosis of CAP? The chest x-ray is essential in the diagnosis of CAP, assessing severity, differentiating pneumonia from other conditions, and in prognostication. (Grade A) What specific views of chest radiograph should be requested? Standing posteroanterior and lateral views of the chest in full inspiration comprise the best radiologic evaluation of a patient suspected of having pneumonia. (Grade A) Are there characteristic radiographic features that can predict the likely etiologic agent from the chest radiograph? There is no characteristic radiographic feature that can predict the likely etiologic agent in CAP. (Grade B)  CHEST XRAY PA VIEW Normal Chest x-ray Pneumococcal pneumonia with Pneumonia, Right lower lung lobar consolidation  WHICH PATIENTS WILL NEED HOSPITAL ADMISSION? A management-oriented risk stratification of CAP based on the patient’s clinical presentation or condition, status of any co-morbid condition, and chest x-ray findings should be utilized in the decision to determine the site of care for patients. (Grade A) Patients with low-risk CAP are considered suitable for outpatient care in the absence of contraindications. (Grade A) Patients with moderate- and high-risk CAP need to be hospitalized for closer monitoring and/or parenteral therapy. (Grade A)  CLINICAL FEATURES OF PATIENTS WITH CAP ACCORDING TO RISK CATEGORIES Low Risk CAP Moderate Risk CAP High Risk CAP Presence of: Any of the following: Any of the criteria under moderate- risk CAP category Stable vital signs; RR < RR >30breaths/min PR >125 plus Severe Sepsis and Septic 30breaths/min PR 40o C C or Temp 60 mmHg mmHg mmHg, No altered mental state of acute Need for Mechanical onset Altered mental state of acute Ventilation No suspected aspiration onset No or stable comorbid Suspected Aspiration conditions Decompensated comorbid conditions Cxray: localized infiltrates Cxray: No evidence of pleural Multilobar infiltrates effusion or lung abscess Pleural Effusion or Lung Abscess WHAT MICROBIOLOGIC STUDIES ARE NECESSARY IN CAP? In low-risk CAP, microbiologic studies are optional. (Grade B) In moderate- and high-risk CAP, blood cultures and gram stain and culture with antibiotic sensitivity tests of respiratory specimens should be done in laboratories with quality assurance. (Grade A) When possible, tests to document the presence of legionella pneumophila are recommended for hospitalized CAP. (Grade B) Invasive procedures (i.E., Transtracheal, transthoracic biopsy, Bronchoalveolar lavage, protected brush specimen) to obtain specimens for special microbiologic studies for atypical pathogens (e.g., Mycobacteria and other microorganisms that will not grow on routine culture) are options for non-resolving pneumonia, immunocompromised patients, and patients in whom no adequate respiratory specimens can be sent despite sputum induction and routine diagnostic testing. (Grade B)  TREATMENT BY CAP RISK CATEGORIES Low Risk CAP Streptococcus pneumoniae Without co-morbid illness: Haemophilus in uenzae Amoxicillin 1 gm TID OR Chlamydophila pneumoniae Extended macrolidesa: Mycoplasma pneumoniae Azithromycin 500 mg OD OR Moraxella catarrhalis Enteric Clarithromycin 500 mg Gram-negative bacilli (among BID those with co-morbid illness) With stable co-morbid illness: β-lactam/β-lactamase inhibitor combination (BLIC)b OR 2nd gen oral cephalosporinc +/- extended macrolidesa Co-amoxiclav 1 gm BID O Sultamicillin 750 mg BID OR Cefuroxime axetil 500 mg BID +/- Azithromycin 500 mg OD OR Clarithromycin 500 mg BID  TREATMENT BY CAP RISK CATEGORIES Moderate Risk CAP Streptococcus pneumoniae IV non-antipseudomonal β-lactamd Haemophilus in uenzae (BLIC, cephalosporin) Chlamydophila pneumoniae + extended macrolides or Mycoplasma pneumoniae Moraxella respiratory fluoroquinolones catarrhalis Enteric Gram-negative (PO) bacilli Legionella pneumophila Ampicillin-Sulbactam 1.5 gm q6h IV Anaerobes (among those with risk OR Cefotaxime 1-2g q8h IV OR of aspiration) Ceftriaxone 1- 2 g OD + Azithromycin500mg OD PO OR Clarithromycin 500 mg BID PO OR Levofloxacin 500 mg OD PO OR Moxifloxacin 400 mg OD PO  TREATMENT OF CAP BY RISK CATEGORIES High Risk CAP Streptococcus pneumoniae No risk for P. aeruginosa: Haemophilus in uenzae IV non-antipseudomonal β-lactam Chlamydophila pneumoniae + IV extended macrolides or IV Mycoplasma pneumoniae Moraxella respiratory fuoroquinolones catarrhalis Enteric Gram-negative Ceftriaxone 2 gm OD OR bacilli Legionella pneumophila Ertapenem 1 gm OD Anaerobes (among those with risk + Azithromycin dihydrate of aspiration) Staphylococcus 500mgODIVOR Levofloxacin 500 aureus Pseudomonas aeruginosa mg OD IV OR Moxifoxacin 400 mg OD IV  TREATMENT OF CAP BY RISK CATEGORIES High Risk CASP Risk for P. aeruginosa : IV antipneumococcal IV antipneumococcal f antipseudomonal β-lactam (BLIC, antipseudomonal β-lactam cephalosporin or carbapenem) (BLIC, cephalosporin or + IV ciprofloxacin / high dose carbapenem) + IV extended levofloxacin macrolidesa + aminoglycosideg Piperacillin-tazobactam 4.5 gm q6h Piperacillin-tazobactam 4.5 gm q6h OR Cefepime 2 gms q8-12h OR OR Cefepime 2 gm q8-12h OR Meropenem 1 gm q8h Meropenem 1 gm q8h + Levofloxacin 750 mg OD IV OR + Azithromycin dihydrate Ciprofloxacin 400 mg q8-12h IV 500mgODIV + Gentamicin3mg/kg ODOR If MRSA pneumonia is suspected, Amikacin 15 mg/kg OD add OR Vancomycin 15 mg/kg q8-12 h OR Linezolid 600 mg q12h IV OR Clindamycin 600 mg q8h IV  HOW CAN RESPONSE TO INITIAL THERAPY BE ASSESSED? Temperature, respiratory rate, heart rate, blood pressure, sensorium, oxygen saturation and inspired oxygen concentration should be monitored to assess response to therapy. Response to therapy is expected within 24-72 hours of initiating treatment. Failure to improve after 72 hours of treatment is an indication to repeat the chest radiograph. Follow-up cultures of blood and sputum are not indicated for patients who are responding to treatment. DURATION OF ANTIBIOTIC USE BASED ON ETIOLOGY ETIOLOGIC AGENT DURATION OF THERAPY (DAYS) Most bacterial pneumonias except enteric Gram- negative pathogens S. 5-7 days aureus (MSSA and MRSA), and P. aeruginosa 3-5 (azalides) for S. pneumoniae MSSA community-acquired pneumonia a. non-bacteremic - 7-14 days b. bacteremic - longer up to 21 days MRSA community-acquired pneumonia Enteric Gram-negative pathogens, S. aureus (MSSA and MRSA), and P. a. non-bacteremic - 7-21 days aerugi- nosa b. bacteremic - longer up to 28 days Pseudomonas aeruginosa a. non-bacteremic - 14-21 days b. bacteremic - longer up to 28 days Mycoplasma and Chlamydophila 10 - 14 days Legionella 14-21; 10 (azalides) RECOMMENDED HOSPITAL DISCHARGE CRITERIA During the 24 hours before discharge, the patient should have the following characteristics (unless this represents the baseline status): 1. Temperature of 36-37.5oC 2. Pulse < 100/min 3. Respiratory rate between 16-24/minute 4. Systolic BP >90 mmHg 5. Blood oxygen saturation >90% 6. Functioning gastrointestinal tract  PREVENTION HOW CAN CAP BE PREVENTED? Influenza vaccination is recommended for the prevention of CAP. (Grade A) Pneumococcal vaccination is recommended for the prevention of invasive pneumococcal disease in adults. (Grade A) Smoking cessation is recommended for all persons with CAP who smoke. (Grade A)  BRONCHIECTASIS refers to an irreversible airway dilation involves the lung in either a focal or a diffuse manner categorized as cylindrical or tubular (the most common form), varicose, or cystic can arise from infectious or noninfectious causes clues to the underlying etiology are often provided by the pattern of lung involvement Focal bronchiectasis refers to bronchiectatic changes in a localized area of the lung Diffuse bronchiectasis is characterized by widespread bronchiectatic changes throughout the lung often arises from an underlying systemic or infectious disease process  BRONCHIECTASIS persistent productive cough with ongoing production of thick, tenacious sputum Physical findings -crackles and wheezing on lung auscultation, some patients exhibit clubbing of the digits PFT – mild to moderate airflow obstruction Acute exacerbations: increase in sputum volume and purulence Diagnosis- cxray- tram tracks indicating dilated airways consistent with bronchiectasis (low sensitivity) Chest CT scan-imaging modality of choice-confirming diagnosis of bronchiectasis (more specific) Tram tracks; signet ring sign; lack of bronchial tapering; bronchial wall thickening in dilated airways, inspissated secretions or cysts emanating from bronchial wall BRONCHIECTASIS CATEGORIES OF BRONCHIECTASIS ON CHEST CT SCAN  BRONCHIECTASIS Treatment of infectious bronchiectasis is directed at control of active infection and improvements in secretion clearance and bronchial hygiene so as to decrease the microbial load within the airways and minimize the risk of repeated infections  PREVENTION Reversal of an underlying immunodeficient state (By administration of gamma globulin for immunoglobulin-deficient patients) and vaccination of patients with chronic respiratory conditions ( Influenza and pneumococcal vaccines) can decrease the risk of recurrent infections Smoking cessation counselling for those who continue to smoke  LUNG ABSCESS Lung abscesses are pus-containing necrotic lesions of the lung parenchyma that result from aspiration of bacteria- laden secretions and show an air- fluid level Lung abscesses are usually characterized as either primary (~80%) or secondary Primary lung abscesses usually arise from aspiration, are often caused principally by anaerobic bacteria, and occur in the absence of an underlying pulmonary or systemic condition Secondary lung abscesses arise in the setting of an underlying condition, postobstructive process ( A bronchial foreign body or tumor) or a systemic process (HIV infection or another immunocompromising condition) Lung abscesses can also be characterized as acute (