acute inflammation Flashcards
What is the general definition of acute exudative inflammations?
Acute inflammations with principal histologic findings including exudation of blood serum and extravasation of blood cells into the inflamed area.
What are the classifications of acute exudative inflammation based on the principal components of the exudate?
- Serous inflammation
- Fibrinous inflammation
- Suppurative/purulent inflammation
- Hemorrhagic inflammation
How can the components of acute exudative inflammation combine?
- Sero-mucous inflammation
- Sero-fibrinous inflammation
- Fibrinous purulent inflammation
What are the possible courses of acute inflammation?
- Dissolution of the exudate (eliminated by macrophages)
- Regeneration of the damaged tissue (restitutio ad integrum)
- Post-infectious disorders (circulating Ag-Ab complexes trigger HSR III)
- Chronic inflammation (when acute inflammation fails to heal)
- Hematogenous dissemination (bacteremia, fungemia, sepsis)
What characterizes acute serous inflammation?
Acute inflammation with exudate of fibrin-free serum.
What are the etiologic factors of acute serous inflammation?
- Hypersensitivity reactions
- Bacterial and viral tissue injury
- Physical and chemical tissue injury
What are some examples of conditions involving acute serous inflammation?
Urticaria in skin
Laryngeal edema
Edema and hyperemia on serous membranes
Serous hepatitis
Serous alveolitis
Acute nephritis
What characterizes seromucous inflammation?
Acute inflammation with a watery exudate of serum and mucus.
What are the etiologic factors of seromucous inflammation?
Back:
- Hypersensitivity reactions
- Bacterial and viral tissue injury
- Physical and chemical tissue injury
What are some examples of conditions involving seromucous inflammation?
- Acute rhinitis (common cold)
- Acute catarrhal bronchitis
- Enteritis
What is the definition of acute fibrinous inflammation?
Acute inflammation with exudation of fibrinogen-containing serum.
What are the etiologic factors of acute fibrinous inflammation?
- Infectious toxic tissue injury
- Chemical and toxic tissue injury
- Excretion of toxic metabolites (uremic toxins)
- Ischemic tissue injury
What are the classifications of acute fibrinous inflammation?
- Fibrinous Serosal Inflammation (e.g., fibrinous pleuritis, fibrinous pericarditis, fibrinous peritonitis)
- Fibrinous Mucosal Inflammation
- Pseudomembranous Croupous Form (Influenza Type)
- Pseudomembranous Necrotizing Form (Diphtheria Type)
- Fibrinous Parenchymal Inflammation (e.g., lobar pneumonia)
Give examples of conditions involving fibrinous serosal inflammation.
Fibrinous pleuritis
Fibrinous pericarditis
Fibrinous peritonitis
What are the two forms of fibrinous mucosal inflammation?
- Pseudomembranous Croupous Form (Influenza Type)
- Pseudomembranous Necrotizing Form (Diphtheria Type)
What is fibrinous pleuritis?
Acute inflammation of the pleura with fibrinous exudate.
What are the causative agents of fibrinous pleuritis?
- Bacteria: Pneumococcus, Haemophilus, Klebsiella, M. Tuberculosis
- Viruses: Coxsackie, echoviruses, adenoviruses
What might be revealed in the aspiration of infected pleural effusion in fibrinous pleuritis?
- High-protein exudate
- Neutrophils in bacterial infections
- Lymphoid cells in viral infections or tuberculosis
What are the clinical presentations of fibrinous pleuritis?
- Auscultatory findings include sounds of pleural friction resembling creaking leather.
- Respiratory excursion is painful.
Describe the macroscopic appearance of fibrinous pleuritis.
- Fibrinous deposits form reticular white-grey membranes resembling “cat’s tongue” (Laenec).
- Variable exudation of fluid.
What are the microscopic features of fibrinous pleuritis?
Filaments of fibrin arranged in a plexiform meshwork.
What are the complications of fibrinous pleuritis?
- The initial serous exudate may become purulent due to superimposed bacterial infection (empyema).
- The fibrinous exudate may become organized to form fibrous pleural adhesions.
- Calcification may be seen in the pleura as a result of old tuberculous pleurisy.
What is fibrinous mucosal inflammation?
It’s an acute inflammation where a wide area of fibrinous exudate forms a pseudomembrane covering the necrosis, limited to the mucosal epithelium.
What are the examples of the pseudomembranous croupous form (Influenza Type)?
- Influenzal tracheobronchitis
- Amebic dysentery
- Ischemic pseudomembranous colitis
What is the clinical presentation of the pseudomembranous croupous form?
In influenzal tracheobronchitis, it presents as croup, with shortness of breath, stridor (whistling sound during inspiration), and a barking cough. Complications include bacterial superinfection.
What characterizes the pseudomembranous necrotizing form (Diphtheria Type)?
It’s an acute inflammation where necrosis extending into the submucosa is covered by a wide area of fibrinous exudate, forming an adhesive pseudomembrane.
What are the examples of the pseudomembranous necrotizing form?
- Diphtheric laryngotracheitis (diphtheria)
- Antibiotic enterocolitis
What is the clinical presentation of the pseudomembranous necrotizing form?
In diphtheric laryngotracheitis, it presents as croup with neuritis of the cranial nerves, leading to aphonia (loss of voice) and development of a pseudomembrane. There’s a risk of asphyxiation, and emergency tracheotomy may be indicated.
what is pneumonia?
Fibrinous purulent inflammation of the lung
What are the main features of pneumonia?
- Monomorphic lesions per stage
- Involvement of a whole segment or lobe
- Bacteria spread through Cohn pores
How is pneumonia clinically classified?
- Community-acquired disease: Usually caused by Gram-positive bacteria.
- Hospital-acquired disease: Usually caused by Gram-negative bacteria.
- Disease acquired in special environments: 4. Usually caused by Legionella (after exposure to contaminated air-conditioning), Chlamydia Psittaci (after exposure to birds’ excreta, especially parrots).
- Disease in immunosuppressed patients: Usually caused by mycobacteria, viruses, and fungi (Pneumocystis Carinii).
- Aspiration pneumonia.
Who is prone to developing pneumonia with Klebsiella?
Homeless and alcoholics