Pathology Flashcards
Second name of neonatal respiratory distress syndrome
Hyaline membrane disease
Neonatal respiratory distress syndrome
Respiratory distress
Refractory to oxygen therapy in newborn
Due to hyaline membranes formation in alveoli because of immaturity of lungs with surfactant deficiency
First symptoms of neonatal respiratory distress syndrome
Resuscitation at birth within 30 minutes : dyspnea tachypnea expiratory grunts cyanosis crepitations in the lungs ground glass opacity over the lungs on x-rays Apneic spells
Neonatal respiratory distress syndrome incidence
60% incidence when born before 28 weeks
30% incidents one born between week 28 and 34
Less than 5% chance is one born After week 34
Risk factors of Neonatal respiratory distress syndrome
Prematurity (born before week 36)
Maternal diabetes
Planned c section
Male gender
Neonatal respiratory distress syndrome pathogenesis
Prematurity Low surfactants High surface tension in alveoli Atelectasis Uneven Perfusion and hypoventilation Hypoxemia and CO2 retention Acidosis vicious cycle because acidosis decreases surfactant release
Pulmonary Hypoperfusion endothelial and epithelial cell damage exudation of plasma into alveoli Fibrosis necrosis and Hyaline membrane increased gradient rate hypoxemia and co2 retention vicious cycle
Type of cell that produce surfactant
Type 2 pneumocyte
Surfactant regulation
Corticosteroid induce production
Insulin repress production
MacroMorphology of neonate respiratory distress syndrome
Lungs look airless, solid, reddish purple,sink in water
Microscopic morphology of respiratory distress syndrome
Atelectatic Aleve alveoli alveoli
necrotic debris in alveolar duct in terminal bronchiole
Eosinophilic hyaline membrane ( in respiratory bronchiole, alveoli , alveolar ducts
What are hyaline membranes
Fibrin with necrotic type 2 pneumocytes , RBC, rare neutrophils , macrophages
Prevention of neonatal respiratory distress syndrome
Delay labor
antenatal steroids to mother
surfactants to very young fetuses
Neonatal respiratory distress syndrome treatment
Oxygen
exogenous surfactants
Neonatal respiratory distress syndrome complications
Retrolental fibroplasia broncopulmonary dysplasia due to oxygen toxicity patent ductus arteriosus intraventricular hemorrhage necrotizing enterocolitis
Why are male neonate more prone to respiratory distress syndrome
Estrogen influence lung developments
Lower rates of alveolar sodium transport channels than in female => fluid accumulation and less gas exchange
Female develop surfactant earlier
Why do diabetic mothers have higher chances of having a neonate with respiratory distress syndrome
Higher chances of pre-terms baby
Inadequate use of glycogen for surfactant Synthesis
Coryza
Infectious rhinitis - common cold
Coryza cause
Virus ( adeno, rhino, RSV, echo)
Most common virus in coryza
Rhino virus
Coryza characteristics
Acute inflammation
Catarrhal
Mucus hyper secretion
Loss of epithelial cells
Bacterial secondary inflammation
Atopic rhinitis (hay fever / allergic rhinitis) causes
Sensitization to house dust mites proteins plants pollen fungi animal allergens
IGE mediated
Atopic rhinitis pathogenesis
Mast cells release histamine: Mucosal edema nasal obstruction redness watery rinorhea goblet cells hyperplasia thickened basement membrane inflammatory exudate with many eosinophils
Chronic rhinitis
Sequel to recurrent acute/allergic rhinitis
Superimposed bacterial infection
Mixed inflammatory exudate
Can extend into sinuses
Nasal polyps cause
Chronic inflammation or type 1 hypersensitivity or asthma
Nasal polyps morphology
Soft
rounds or elongated masses
pale gray brown
0.5 to 2 cm
Nasal polyps site
Middle turbinate
Nasal polyp histology
Surface epithelium with meta plasia
Allergic type have lot of eosinophils
Nasal polyp complications
Loss of smell
Frequent infections
Acute sinusitis
Acute inflammation of sinuses
Cause of acute sinusitis
Acute /chronic rhinitis with edema and sinus Ostia blockage
Bacteria in secondary infection in acute sinusitis
Staph aureus
H influenza
Pneumococcus
Strep pyogenes
Acute sinusitis complications
Empyema
Chronic sinusitis
Failure to resolve acute sinusitis
Origin of severe form of chronic sinusitis
Fungal origin
Necrotizing nasal lesions
Acute fungal infection
Necrotizing nasal lesions Morphology
Granulomatosis - Polyangitis (wegeners granulomatosis)
giant cell granulomas of lungs
Polyarteritis
renal damage
Extranodal T cell then lymphoma in elderly
Pharyngitis and tonsillitis
Non-specific inflammation of needs a pharynx
Common causes of pharyngitis and tonsillitis
Mostly viral
sometimes bacterial
Characteristics of pharyngitis and tonsillitis
Red
Oedematous mucosa
Enlarged tonsils and lymph node
Of what bacteria is pharyngitis and translate is an important sequelae
B haemolytic strep( pyogenes)
Benign tumors of nose Sinuses nasopharynx larynx
Hemangiomas
squamous papillomas
juvenile angiofibroma
Juvenile angiofibroma
Benign tumor of nasopharynx in childhood almost exclusive to male
Vascular and epistaxis
Malignant tumor of nose nasopharynx pharynx sinuses
Squamous cell carcinoma Adenocarcinoma (common in wood workers) lymphoma sarcomas Olfactory neuroblastoma Nasopharyngeal carcinoma
Naso pharyngeal carcinoma incidence
Twice in males
Peak at 10-20 and 6th decade
Causes of nasal pharyngeal carcinoma
Hereditary
Age
EBV
diet
Acute epiglotitis causes
RSV
H influenza B
streptococcus
A cute epiglottis presentation
Respiratory obstruction by edema
dyspnea worse in supine position
Managements of acute epiglottitis
Emergency so may require tracheostomy
Acute Laryngotracheo bronchitis
Gradual onset of cough
stridor
croupy cough
Benign tumors of larynx and trachea
Squamous papilloma (Single in adults and multiple in children) polypoid mass on true vocal cord
Causes of benign tumors of larynx in trachea
Hpv6 /11
Presentation of benign tumors of larynx and trachea
Hoarse voice
Bleeding
Laryngeal fibroma
Vocal cords polyp
Covered by epithelium with a core of myxomatous connective or dense fibrocollagenous tissue
Causes of laryngeal fibroma
Common in singers smokers and in Myxedema
Malignant tumors of larynx and trachea
Squamous cell carcinoma of larynx ( commonest neoplasm of larynx)
Origin of squamous cell carcinoma of larynx
Squamous epithelium a vocal cords
cause of squamous cell carcinoma larynx
Smoking excess alcohol previous irradiation zinc and vitamin a deficiency asbestos HPV infection
Squamous cell carcinoma of larynx incidence
Higher in male Chronic smokers
Morphology of squamous cell carcinoma of larynx
Severe dysplasia
carcinoma in situ
metastasis to cervical notes
Blood borne metastasis to lungs liver bones
keratinizing and non-keratinizing squamous carcinoma & spindle cell
Factors affecting local defense in respiratory tract
Suppression of cough reflex like in coma or anesthesia
Ciliary defects
Mucus disorders
acquired or congenital hypogammaglobulinemia ( low IgA)
Immunosuppression
depressed alveolar macrophage function
pulmonary edema with fluid accumulation in alveoli
Specific infections of LRT
Bronchitis
Bronchiolitis
Pneumonia
Lung abscess
Acute bronchitis
Acute inflammation of bronchi
Acute bronchitis causes
Viruses - RSV
Pollutants
SO2
Smoke
Acute bronchitis presentation
Cough Dyspnoea Tachypnoea Sputum production May have laryngotracheobronchitis and lungs issues
What disease superimposed with chronic obstructive airway disease
Acute bronchitis
Bronchiolitis
Inflammation of bronchioles
Cause of bronchiolitis
Viral disease in children (RSV)
Bronchiolitis presentation
Dyspnoea
Tachypnoea
Resolve in few days
Rarely bronchopneumonia
Pneumonia
Inflammation affecting lungs parenchyma
Exudate formation leading to consolidation of lung tissue
Clinical classification of pneumonia
community acquired acute pneumonia
Health care associated pneumonia
Hospital acquired pneumonia
Aspiration pneumonia
Chronic pneumonia
Necrotizing pneumonia and lung abscess
Pneumonia in immunecompromised Host
Anatomic classification of pneumonia
Bronchopneumonia : patchy consolidation of lungs 3-4cm , common at autopsy
Lobar pneumonia : acute bacterial infection by droplets acquired by community , diffuse consolidation of one or more lobes or segments by fibrinosuppurative exudate , accompanied by pleural reaction with fibrin deposition
Causes of lobar pneumonia
90-95% : strep pneumonia type 1,3,7,2
Klebsiella pneumoniae
Staph aureus
H influenza
Pseudomonas
Proteus
Causes of bronchopneumonia
Staph Strep Pneumococci H influenza Pseudomonas
Pneumonia pathogenesis
Impaired defense mechanism by virulent organisms
Lobar pneumonia -> extensive exudate -> organism spread rapidly through pores of kohn too other alveoli
Bronchopneumonia involve bronchiole and spread to adjacent alveoli
Lobar pneumonia morphological stages
Congestion (lung heavy , red, Vascular engorgement intra-Alveolar fluid With few neutrophils and many bacteria
Red hepatization (the lung firm red, airless , liver like consistency, many RBC and neutrophils, breaks when firm gentle pressure instead of regaining shape )
Grey hepatization ( lung firm, gray brown, dry surface, progressive disintegration of RBC, fibrinosuppurative exudate )
Resolution ( consolidated exudate progressively digested by enzymes, resorted by macrophages or coughed up, inflammation resolution)
Pneumonia complications
Local: Lung abscess solid fibrotic lung Pleural effusion Empyema thoracis
Systemic: Bacteraemic dissemination Meningitis Pericarditis kidney or splenic abscess septicemia
Symptoms of pneumonia
Fever (5days, and drops 2 days after antibiotics) cough sputum production chest pain due to pleural reaction dullness bronchial breathing
X-ray findings of pneumonia
Opaque Well delineated lobe in lobar pneumonia
Focal opacities in bronchopneumonia
Community acquired viral pneumonia
Acute febrile respiratory disease with Patchy inflammatory changes in Lungs
confined to the alveolar septa and pulmonary interstitium
Causes of Community acquired viral pneumonia
Viruses influenza RSV Varicella adenovirus rubeola CMV SARS Coxiella burnetti chlamydia mycoplasma
Community acquired viral pneumonia morphology
Lung subcrepitant, patchy, unilateral or bilateral
no reaction at pleura
Septa widens by edema mononuclear cells and very few neutrophils
Alveoli mostly free of exudates
Few cases with exudate and hyaline membrane
Community acquired viral pneumonia symptoms
Severe cold cough fever headache muscle aches leg pains
Pneumonia in the immunocompromised
Due to opportunistic infections In debilitating disease, therapy for organ transplants , tumors , irradiation
Pneumonia in the immunocompromised presentation
Fever
short breath
cough
Immunocompromised pneumonia x rays
Lung infiltrates focal infiltrate ( with CMV, P Carinii, aspergillus, cryptococcus, tb, rubeola, drug run, malignancy )
Diffuse infiltrate ( gram neg bacilli, stap aureus, aspergillus, candida, cryptococcus, Nucor, p caring, legionella, malignancy )
Aspiration pneumonia
Inflammation and consolidation of the lung went fluids or foods is aspirated into lung
Risk factors of lung aspiration
Sedition alcohol abuse operations Coma stupor laryngeal carcinoma severe debilitation
What part of the lung will be affected if you aspirate something when laying on the back
Lower lobe
What part of the lung will be affected if you aspirate something when laying on the side
Upper lobe
Endogenous Lipid pneumonia
Airway obstruction by distal collection of foamy macrophages and giant cells
Exogenous lipid pneumonia
Aspiration of lipid rich material like paraffin oil in nasal drops, palm oil when given to children to Treats Toxicity, Vacuoles of lipids from foreign body giant cells in lung
Lung abscess
Local suppurative process in the lung with necrosis of lung tissue
Predisposition to lung abscess
Oral pharyngeal surgery or disease sinobronchial infection dental sepsis bronchiectasis complications of pneumonia
Causes of lung abscess
Potentially any organism usually Aero and anaerobic strep, staph aureus, gram neg organism
60% of cases => fusobacterium, peptococcus
Introduction of organisms to form lung abscess
Aspiration of infected material from mouth and pharynx
Primary bacterial or fungal infection of lung
Septic embolism
Neoplasia
Direct penetrating injuries
cryptogenic
Lung abscess morphology
Size goes from micro to macro
Any parts of the lung can be affected
What side of the long is more affected by lung abscess
Right side because more aspiration
Lung abscess x ray
Air fluid level
In what case of lung abscess can you get gangrene of the lung
Super imposed saprophytic infection ( large fetid green black area)
Lung abscess clinical presentation
Fever
cough with copious sputum (foul smelling and bloody or purulent)