Pathology Of The Respiratory System PART 2 - Dr. Singh Flashcards
Age most high prevalence of pneumonia needing hospitalization
18-64yo
= can cause sepsis and shock
Leading cause of death in children under 5yo
Bronchopneumonia vs lobar pneumonia
Bronchopneumonia: spread through airway and effect areas that airway goes to
Lobar pneumonia: effects the lobe
4 stages of lobar pneumonia
- Congestion : due to Blood buildup and
- Red Hepatization : inflammatory cells and RBCs going into alveolar space (filling with blood) ——> looks like a red liver
- Grey Hepatization : inflammation and debri is left , Blood leaves side no more inflammatory cells needed) ——> looks like a grey liver
- Resolution : M clean and some fibrosis
3 complications of Lobar pneumonia
- Abscess (c shaped or circular wall white , inside is white on bottom with air-fluid line on CXR)
- Empyema (bacteria invading into pleural space)
- Baceremia (bacteria invade into BVs)
What are the community acquired bacterial pneumonia MOST common and some others
- Streptococcus Pneumonia
- H. Influenzae
- S. Aureus
- K. Pneumoniae
- P. Aeruginosa
Streptococcus Pneumonia looks like Ab
Gram + diploccoi (pairs in chains) looks like a spear head
= most common community acquired pneumonia
= vaccines are given in > 65yo
Haemophilus influenzae Pneumonia
Bacteria with high virulence in children
Vaccine in children under 5yo
Steph Aureus
Abscess formation in lung
IV drug users
Klebsiella Pneumonia
Alcoholics ——> aspirations
Current Jelly Sputum (hemorrhage + mucous = coughed up)
Viral influenza in children
Cause bacterial haemophilus influenza to come and is what actually causes fatal SXs
Pseudomonas Aeruginosa who, and associated with
Another CAP
= CF are prone to it usually by age 10yo
= green rusty looking, grape like smell
Typical pneumonia
= fast onset
= resp sx
= consolidation on a lobe seen on CXR
= children and older adults
Atypical Pneumonia
= slow onset
= systemic SXs
= patchy infiltrates on CXR
= young adults, teens, older children
Typical pneumonia microorganisms
- Strep Pneumonia
- H. Influenza
- S. Aureus
- K. Pneumonia
- P. Aeruginosa
Atypical Pneumonia microorganisms
- Mycoplasma Pneumonia
- Legionella Pneumophilia
- Chlamydia pneumonia
- Chlamydia Psittaci
Mycoplasma Pneumonia looks like and what it does
Small tiny no cell wall organisms that can travel down far in the airway
= walking pneumonia
= no gram charge
Legionella Pneumophilia type of organism and where it is found
Gram - bacillus growing in WARM FRESH WATERS = air conditions = Misters = Hot Tubs (Airborne)
Community - Acquired Viral pneumonia 4 of them
- H1N1 Influenza
- SARS
- COVID-19
- Respiratory Syncytial Virus
Viral pneumonia doesn’t what usually on CXR
Diffuse and all over usually not lobar and in one space
Bacterial pneumonia does what to lung tissue
Destruction of lung parenchyma and infiltration on N and many RBCs into alveolar space
Viral Pneumonia does what to lung tissues
Lymphocytes and plasmacytosis into interstitial spaces all around the alveoli
2 proteins of the Influenza
- Hemagglutinin = attachment to cells
- Neuraminidase= release of virus from cell and replication
= these are the variants between the strains
Tamiflu is what
Oseltamivir
= BLOCKS Neuraminidase (cutting virus off the cell to go one a bind and replicate on other cells)
= the Haemagglutinin is stuck on the cell
Influenza SX
Body aches, chills, headache, fever, fast onset = which is not seen as much in colds
Antigenic SHIFT vs Antigenic DRIFT in influenza
SHIFT : EPIDEMIC , minor changes in neuramidase and haemugglutin proteins
= you still have some immunity
DRIFT : PANDEMICS , huge genomic alterations in H and N proteins and creates a virus that is completely new to body
= usually from animals
H1N1 influenza caused what
Antigenic drift causing the Spanish Flu ( from bird)
H2N2 = Asian flu
H3N2 = Hong Kong flu
Fastest replicating virus is what type of route and which dies ease is it linked to
ssRNA +
= SARS and COVID -19 (SARS-Co-2)
COVID-19 enters body how and what happens
Binds to ACE2 Receptors in gut and lungs
- Cytokines storm
- Damage and pulmonary edema (ALSO IN ARDS)
- DVT prone pts —> PE
COVID lung histology
Hyaline membrane from fibrin and edema and inflammation
= alveoli fill up with cells and blood (like in bacterial pneumonia——> it came from COVID) as seen in viral influenza in children
Coagulation in lungs for COVID
Microthrombi in lungs = deadly
Megakaryocytes (not supposed to be in circulation however cause platelets microcoagulation in COVID) ——> microthrombi in heart and lungs and other vessels in the body
Neonatal most common pneumonia
Bacterial (Group B Streptpcoccal, gram - bacilli, Listeria)
= from mother
Children over 1mo most common pneumonia
VIRAL : Respiratory Syncytial Virus, Parainfluenza influenza A + B, Adenovirus, Rhinovirus
BACTERIAL : Strep Pneumonia, H. Influenzae, M. Catarrhalis, S. Aureus
Older children and adolescents most common type of pneumonia
M. Pneumonia , C. Pneumonia (Walking pneumonia)
= not as much RSV
Groups of Strep for diseases
Group A Streptococcus Pharyngitis : Rheumatic Fever
Group A B-Hemolytic Streptococcus : Lymphangitis
Group B Streptococcus : Neonatal Pneumonia
RSV type of virus and looks like
Paramyxovirus
= multinucleated (inclusion bodies inside)
RSV SX
Babies come in with = cough, runny nose = wheezing, dyspnea = Tachy = cyanosis
RSV what happens in the lung
Thickening of walls of bronchus and mucous buildup
= damaging respiratory epithelium
What can also look like the multinucleated syncytial bodies in RSV
Human Metapneumovirus
Parainfluenza
Measles
Presentations of BACTERIAL PNEUMONIA 5
- Fast onset, not airborne unless (Legionella or Pertussis), not easily spread as much
- HIGH FEVER
- Crackles in lung
- Lobar Consolidations seen
- Can go into pleura
Presentations of VIRAL PNEUMONIA 6
- Slow onset
- Commonly spread easily (airborne)
- Low fever
- Wheezes in lung
- Diffuse infiltration in CXR
- Not usually in pleural cavity
Which microorganisms can cause lung abscess
- S. Aureus
- K. Pneumonia
- Anaerobic bacteria (since they like to get walled off)
(Also in chronic alcoholism —> aspirations)
lung abscess most common location
Right middle or lower lobes (after carina the slope of RIGTH bronchus is more steep)
(CLASSIC ASPIRATION PNEUMONIA)
TB infection Primary lesion is called what
Ghon complex = 1st caseating complex (in the periphery and hilum that it’s connected to) of the lung
Miliary TB
As TB gets access to the Blood stream they disseminate and go the liver and spleen
Ceseating granuloma has what special cells around the granuloma and how do you stain for this and what do you seen in the stain
Giant multinucleated cells
Acid Fast : blue background and red/purple lines
4 causes of granulomas in the lung
- TB
- Sarcoidosis
- Hypersensitivity pneumonia
- Vasculitis (GPA)
Chronic Pneumonia most common fungal causes
Histoplasma
Blastomycosis
Coccidiomycosis
Histoplasma where and what does it do
Midwest and Caribbean (ohio, Mississippi River valley)
= in lungs granulomas form ——> calcifications and coin lesions in cxr, however no real sx
= can be aggressive in immunocompromized (chronic pneumonia)
Histoplasma looks like what on histology
Pumpkin seeds
Blastomyces dermatitides location and what does it do
Central and SE US (Ohio, Mississippi River valley)
= granulomas in lung
= can infect skin
= immunocompromized can get chronic pneumonia
Blastomyces dermatitides looks like what on histology
Broad Based Budding (2 circles that look like they are budding that are tightly attached to each other)
Coccidiodes immitis location and what does it do
SW US and Mexico
= lung granulomas + high Eosinophils
= self -limited pneumonia
= can become disseminated infection esp immunocompromized
Coccidiodes immitis looks like what
Perfect round circle with a bunch of smaller circles inside it (plasmocytes)
Most common pneumonia causes in HIV patients
Pneumocystis Jiroveci (carinii) CMV
Pneumocystis Jiroveci is what and what happens
Fungal infection
= AIDS get pneumonia
= very elderly and immunocompromized pts can also
Pneumocystis Jiroveci looks like what on histology
Cup shaped yeast
Cytomegalovirus is what and does what and what it looks like on histology
- Viral infection = Bid Cell Virus
- Pneumonia in immunocompromized
- Cowdry image (like an eyeball, one of the owl eyes, you see virus in nucleus + cytoplasm)
Mycobacterium Adium Complex (MAC) is what and stain for it
Immuocompromized and pneumonia
= mycobacterium in acid fast stain
After transplantation of lungs how can you see if they are rejecting the lungs or infection of lungs
REJECTION = mononuclear infiltrates of lymphocytes = give steroids
INFECTION fungal or viral = you see the organism = treat that and lower steroids
Lung cancer is associated with what
= tobacco smoking = Radiation = uranium = asbestos = radon
Gene protecting from lung cancer
Polymorphism in P450 (DNA repair genes)
SCC effects what cells in the lung and what genes are associated with it
Basal cell——> ciliated cells (Bronchous most proximal)
SOX2, NOTCH, CDKN2A
Small Cell carcinoma effects what cells in the lung and what genes are associated with it
Neuroendocrine cells (thought out the respiratory epithelium)
= TP53
=RB1
Adenocarcinoma effects what cells in the lung and what genes are associated with it
Type 2 alveolar cells
= EGRF-RAS pathway (K-RAS, B-catenin)
= sometimes p53 also
Smoking usually cause what lung cancers
SCC
Small Cell Carcinoma
Most common lung cancer
Adenocarcinoma
Adenocarcinoma first stage and what is the characteristics of this stage
Atypical Adenomatous Hyperplasia (AAH)
= <5mm, dysplastic pneumocytes present in alveoli
= some interstitial fibrosis