Snapshot A 87-year-old man is brought to the ED from a long-term care facility who reports that he woke up in the middle of the night covered in sweat, with a high fever. His CXR is shown. Introduction Infection of the lung(s) that usually occurs in defined lobar patterns, but might also be diffuse Common causes of pneumonia are often categorized by age groups as follows: neonates (0-6wks) Group B Strep E. coli children (6wks-18yrs) RSV (<1 yr) Parainfluenza (2-5yrs) Mycoplasma Chlamydia pneumoniae Streptococcus pneumoniae adults (18-40 yrs) Mycoplasma C. pneumo S. Pneumo adults (40-65yrs) Mycoplasma S. pneumo Haemophilus influenzae Anaerobes viruses elderly (> 65yrs) S. pneumo viruses Anaerobes H. flu Gram(+) rods Recurrent pneumonia occurs in select patient groups including chronic obstruction i.e. foreign object aspiration classically right middle or lower lobe pneumonia bronchogenic carcinoma lymphoma immumodeficiency Wegener's granulomatosis carriers of unusual organisms Nocardia Coxiella Aspergillus leads to fungal balls Pseudomonas CF patients difficult to treat definitively Patient characteristics and history can lead to or narrow suspected pathogens atypical presentation Mycoplasma Legionella Chlamydia hospital-acquired pneumonia (nosocomial) Staph Gram(+) rods anaerobes Gram(-) rods immunocompromised hosts Staph Gram(+) rods fungi viruses HIV patients Pneumocystis carinii (jiroveci) - however, S. pneumoniae remains the most common causative bacterial pathogen overall in HIV+ patients CMV aspiration pneumonia anaerobes usually occurs in intubated patients or those with speech/swallow pathology air conditioning in close quarters or aerosolized water Legionella alcoholics/IV drugs users Klebsiella current jelly sputum S. pneumo Staph. aureus bird droppings Chlamydia psittaci or Histoplasma spp recent immigrant Tuberculosis CF patients Pseudomonas breath smells like grapes S. aureus COPD patients H. flu Moraxella catarrhalis S. pneumo Known TB patient Aspergillus (in pulmonary cavitation) Postviral S. aureus - may cause necrotizing pneumonia H. flu Presentation Symptoms classically presents with sudden-onset fever productive cough purulent yellow-green hemoptysis dyspnea night sweats pleuritic chest pain atypical presentations are gradual in onset and flu-like dry cough headaches myalgias sore throat Physical exam auscultation of the lungs reveals decreased or bronchial breath sounds crackles/rales wheezing a-to-e egophany percussion reveals dullness over affected lobe(s) tactile fremitus elderly and patients with chronic lung disease, diabetes, or immunocompromised status may have minimal exam findings Evaluation CXR may show lung consolidation in affected lobe(s) establishes diagnosis in combination with Gram stain or culture CBC elevated WBC with pathogen-dependent shift Sputum Gram stain and cultures identify pathogen directs medical treatment ABGs characterizes respiratory status and compromise hypoxia may cause increased respiratory rate, resulting in respiratory alkalosis Specific pathogens Legionella urine Legionella antigen test sputum staiing with direct fluorescent antibody culture Chlamydia pneumoniae serologic testing culture PCR Mycoplasma diagnosis is usually made clinically serum cold agglutinins serum Mycoplasma antigen Differential Common cold, influenza, pulmonary effusion, tuberculosis, acute respiratory distress Treatment Non-operative outpatient oral antibiotics in uncomplicated cases medications directed at sensitivity of known pathogens and/or additional broad coverage in-hospital IV antibiotics recommended in patients >65 yrs and/or with multilobar pneumonia may be necessary in patients with significant comorbidities including alcoholics COPD malnutrition diabetes immunocompromised altered mental status required in unstable patients or those in respiratory failure Operative interventional treatments are rare in cases of pneumonia usually indicated to treat secondary pathology recurrent pleural effusions fungal ball removal intubation Prognosis, Prevention, and Complications Prognosis highly depends on patient comorbities and type of pneumonia usually resolve without complications in otherwise healthy patients Prevention safe medical practice (i.e. handwashing) can prevent spread of nosocomial disease carefully monitor intubated patients and those with speech/swallow pathology incentive spirometry and deep breathing post-operatively can prevent atelectasis and resultant pneumonia Complications if left untreated, can lead to respiratory failure, sepsis, shock, and/or death