Pneumonias Flashcards
Clinical features of pneumonia
- fever & chills
- productive cough w/ yellow-green (pus) or rusty (blood) sputum
- tachypnea w/ pleuritic chest pain (due to presence of bradykinin & PGE2)
- decreased breath sounds
- dullness to percussion
- elevated WBC
Physical diagnostics of lung consolidation
Difference from pleural effusion?
decreased percussion, increased TVF, egophony( is an increased resonance of voice sounds heard when auscultating the lungs, often caused by lung consolidation and fibrosis.) , and pectoriloquy = consolidation
Effusion will only have decreased percussion
Diagnosis pneumonia
Chest xray—sputum gram stain & culture–blood cultures
Complications of Pneumonia
- abscess formation
- empyema
- intralveolar exudate >> complete fibrosis of that part of the lung
- bacterial dissemination >> meningitis, arthritis, endocarditis
Streptococcus pneumoniae
Causes which disease? Seen in? Treatment?
- gram positive dipplococcus
- Most common cause of community-acquired pneumonia and secondary pneumonia (viral URI > bacterial pneumonia)
- Seen in middle-aged adults & elderly; especially common in immunoglobulin deficiency, those w/ chronic conditions (CHF, diabetes, COPD), and those w/ lack of splenic function
- Treatment: penicillin G
Pneumococcal pneumonia
Presentation? Complications? Prevention?
- Presenation: sudden onset of chills, chest pain, rusty sputum
- Complications: Empyema, effusion (no residual lung damage)
- Prevention: Pneumovax
Klebesiella pneumonia
- most frequent cause of gram neg. pneumonia
- enteric flora that is aspirated
- most commonly affects debilitated and malnourished adults, specifically *diabetics *alcoholics *elderly in nursing homes
- thick mucoid capsule >> gelatinous currant jelly sputum
- complicated by abscess
Phases of Lobar Pneumonia
- Congestion - due to congested vessels & edema
- Red hepatization - due to exudate, neutrophils, and hemorrhage filling the alveolar air spaces, giving normally spongy lung a solid consistency
- Gray hepatization - due to degradation of red cells within the exudate
- Resolution - Regeneration of alveolar lining via type II pneumocyte stem cells (can cause pleuritis and permanent adhesions)
What is it?
What characterizes it?
Areas involved?
Bronchopneumonia
- characterized by scattered patchy consolidation centered around bronchioles
- acute inflammatory infiltrates from bronchioles into adjacent alveoli
- often multifocal and bilateral
- caused by a variety of bacteria
Types of pneumonia are?
- lobar pneumonia - effects “section” lobe of lung
- Bronchial pneumonia (Bronchopneumonia)- effects patches of the lungs
Causes of Bronchopneumonia
Who do you see these causes in?
- Staphylococcus aureus - 2nd most common cause of secondary pneumonia; complicated by abscess or empyema (nosocomial)
- Haemophilus influenzae - common cause of secondary pneumonia and most common cause of exacerbated COPD; elderly
- Pseudomonas aeruginosa - pneumonia in CF; also neutropenic & ventilated patients (nosocomial); fulminant infection
- Moraxella catarrhalis - CA pneumonia (esp. in elderly) & 2nd most common cause of exacerbated COPD
- Legionella pneumophila - CA pneumonia, pneumonia on COPD, or pneumonia in immunocompromised states; transmitted from water source; intracellular - use silver stain; can also use urine antigen
- S. pneumoniae & Klebsiella can also cause
Lung Biopsy- what do you see?
Bronchopneumonia -notice the neutrophils in the alveolar spaces
What is it? Where is it? Presentation?
Interstitial Pneumonia = Atypical Pneumonia (the infection is caused by different bacteria than the ones that cause typical pneumonia. These include Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydophila pneumoniae. Atypical pneumonia also tends to have milder symptoms than typical pneumonia.)
- diffuse interstitial infiltrates involving ≥ 1 lobe; alveolar spaces free of exudates
- presents with mild UR symptoms: cough, mild fever, minimal sputum- can be apparent respiratory distress that doesn’t match severity of symptoms (but CXR can look worse than pt.)
- bacterial and viral causes
Causes of Interstitial Pneumonia
- Mycoplasma pneumoniae - most common; affects young adults & children (military recruits/college students in dorm); Complications - autoimmune hemolytic anemia (IgM to I antigen on RBCs > cold hemolytic anemia) and erythema multiforme (nosocomial)
- Chlamydia pneumoniae - 2nd most common; young adults (sim to MP); can also see chlamydia psittaci (from bird) - causes interstitial pneumonia with BAL showing intracellular organisms
- RSV-Respiratory syncytial virus- - most common cause in infants
- CMV (Cytomegalovirus (from the Greek cyto-, “cell”, and megalo-, “large”) is a genus of viruses in the order Herpesvirales, in the familyHerpesviridae, in the subfamily Betaherpesvirinae. Human and monkeys serve as natural hosts.) - due to posttransplant immunosuppressive therapy
- Influenza - elderly, immunocompromized, and those w/ preexisiting lung disease; increases risk for superimposed S aureua or H flu
- Coxiella burnetti - high (Q) fever; seen in farmers & veterinarians (spores on cattle from ticks or in cattle placenta); rickettsial but distinct from others because it (1) causes pneumonia, (2) doesn’t require arthropod vector (heat resistant endospore) (3) no rash
What is happening here?
Interstitial Pneumonia
- air sacs predominantly empty
- inflammatory cells in wall of interstitium
Aspiration Pneumonia
Seen in? Causes? Clinical Features?
most often due to anaerobic bacteria in orpharynx (Bacteroides, Fusebacterium, Peptococcus)
Aspiration (or inhalation) pneumonia is a condition in which a dog’s lungs become inflamed due to the inhalation of foreign matter, from vomiting, or from theregurgitation of gastric acid contents. Aspiration pneumonia can also be a direct result of a neuromuscular disorder, which would cause difficulty with swallowing, as well as problems associated with the esophagus, with possible paralysis of the esophagus.
Other causes for a dysfunction of the lungs may be an obstructed airway, or inhalation of gastric acids, which can cause extensive damage to the internal tissues of the lungs. Bacteria present in the inhaled foreign matter may also bring about infection.
Aspiration pneumonia is more prevalent in dogs than cats. If you would like to learn how this disease affects cats, please visit this page in the PetMD health library
