[MICRO 20] LEC 9 - Microbial Respiratory Diseases

UPPER RESPIRATORY TRACT INFECTIONS

Any infection that involves the nasal cavity, paranasal sinuses, pharynx or larynx

frontal, ethmoid, sphenoid, maxillary

The nasal cavity is connected to 4 sinuses which are air-filled spaces inside the bones that surround the nose. What are those 4 sinuses?

Paranasal sinuses

act as tiny echo chambers that help amplify the sound of your voice which is why you sound so different when they’re clogged with mucus during a cold

Tonsils

small clumps of lymphoid tissue that acts as body’s first line of defense that swallow viruses and bacteria that enter through the mouth or nose

Epiglottis

acts like a lid that seals the airway off when you’re eating so that the food can only go one way down the esophagus and towards the stomach

2 meters or 6 ½ ft

When an infected person sneezes or coughs, they spread thousands of droplets containing these pathogens into the local area up to about _____________ away.

TRUE

[TRUE OR FALSE] Most of respiratory viruses or bacteria can also survive on surfaces for a few hours so it’s possible to get them by touching a surface.

goblet cells and submucosal glands

_________ cells and ________ glands in the airways start to produce a lot of mucus to try to trap and eventually expel infectious pathogens in the respiratory tract.

Rhinitis

infection inside the nasal cavity

Rhinosinusitis

infection in both the nose and sinuses

Aspergillus

Individuals that are immunocompromised like those taking chemotherapy, rhinosinusitis can be caused by fungi like ______________.

Pharyngitis

infection of pharynx or throat

Epstein Barr

virus that largely bypass the nose and just attack the pharynx

Strep throat

Some bacteria like Group A Streptococcus can also cause pharyngitis called ________

Laryngitis

infection in the larynx

FALSE; Haemophilus influenzae have a special preference

[TRUE OR FALSE] Streptococcus pneumoniae have a special preference for the superior portion of the larynx and the epiglottis causing epiglottitis

C

Causes a runny/stuffy nose & sneezing A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

D

Causes sore throats A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

A

Causes a hoarse voice and dry cough A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

F

Causes pain or pressure on the face near the infected sinus and change a voice A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

B

causes painful swollen tonsils—making it hurt to swallow A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

E

causes trouble breathing; like a person talking with a hot potato voice in their mouth or they are in a tripod position A. Laryngitis B. Tonsillitis C. Rhinitis D. Pharyngitis E. Epiglottitis F. Rhinosinusitis

TRUE

[TRUE OR FALSE] Streptococcus pyogenes has a thick peptidoglycan wall which takes in purple dye when gram stained

Streptococcus pyogenes

-It is non-motile and does not form pores -Facultative anaerobe bacteria -Catalase negative -Beta hemolytic -Bacitracin sensitive

M protein

A protein that contributes to the virulence factors of strep pyogenes. It also helps in attachment to skin or pharyngeal mucosa; mimics body proteins

Streptolysin O & S

Toxins used in the bloodstream that causes hemolysis of red blood cells (leading to cell destruction)

Erythrogenic Toxins

causes increased hemolysis in dermal and submucosal blood capillaries

Hyaluronidase

Destroys hyaluronic acid that keeps the cells of connective tissues and blood vessels tightly linked

SpeA and SpeC

Superantigens that do not need to be eaten up by antigen-presenting cells such as macrophage to produce an immune response from T cells.

cytokine storm

a phenomenon which interact immediately with the Class II MHC on the surface of the macrophage, forming a superantigen MHC complex which then interacts with the T cell receptor and stimulates up to 30% of the entire T cell population.

Toxic Shock Syndrome (TSS)

happens when a cytokine storm triggers widespread systemic vasodilation, resulting in drop of blood pressure leading to poor perfusion of vital organs

skin, mucosa of pharynx or throat, vagina, rectum

4 body organs that are colonized by strep pyogenes but do not do any harm as long the immune system keeps them in check, restricting their growth, and preventing them from spreading somewhere else in the body

strep pharyngitis or strep throat

inflammation of the pharyngeal mucosa and tonsils

Post-infectious Sequelae

Complications that arise even after the bacteria has been eliminated from the body.

penicillin

common treatment for strep throat

culture from throat swab

recommended diagnostic test for strep throat

cephalosporins (ceftriaxone) or Macrolides (azithromycin)

treatment for strep throat for those who are allergic to penicillin

penumonia

due to inflammation of the lung alveoli from an infection.

pleuritic chest pain

symptoms in pneumonia which the infection is found near pleural surface and pain that worsens with inspiration

egophony

- Increased resonance of transmitted sounds. - Makes letter “E” sound like letter “A”

increased tactile fremitus

Increased sensation of vibration when palpating over the infected area and asking the individual to speak

atelectasis

- Collapse of a region of the lung (a complication that often occurs after surgery) - Wedge-shaped region - Apex at the Hilum - Ipsilateral Shift of structures due to volume loss

COMMUNITY ACQUIRED PNEUMONIA (CAP)

Pneumonia was acquired anywhere in the community, but not in a hospital

HOSPITAL ACQUIRED PNEUMONIA (HAP)

Pneumonia acquired more than 48 hours after admission to a hospital.

VENTILATOR-ASSOCIATED PNEUMONIA (VAP)

Pneumonia was acquired more than 48 hours after endotracheal intubation.

Empiric coverage

antibiotics are selected based on most likely pathogen

Confusion

C in curb-65 stands for

respiratory rate

R in curb-65 stands for

uremia

U in curb-65 stands for

blood pressure

B in curb-65 stands for

inpatient and ICU

Patient is treated in an _________ setting when Sputum & Blood Cultures are sent for certain individuals.

PNEUMONIA SEVERITY INDEX

more elaborate scoring system for the treatment of CAP

FALSE; ciproflaxin does not reach high enough levels in the lungs to be effective

[TRUE OR FALSE] Ciproflaxin is recommended for treating an outpatient with comorbidities that is currently suffering from CAP

Pneumococcal Urine Antigen

when lobar pneumonia is suspected, ______________ test can be done to confirm the diagnosis

FALSE; Staphylococcus aureus

[TRUE OR FALSE] Post-viral pneumonia is caused by Moraxella catarrhalis

C

Recurrent pneumonia is caused by what bacteria A. Staphylococcus aureus B. Haemophilus influenzae C. Bukholderia cepacia D. Atypical bacteria

D

Diffuse interstitial pneumonia is caused by what bacteria A. Staphylococcus aureus B. Haemophilus influenzae C. Bukholderia cepacia D. Atypical bacteria

B

COPD is caused by what bacteria A. Staphylococcus aureus B. Haemophilus influenzae C. Bukholderia cepacia D. Atypical bacteria

Bullous myringitis

Blistering infection of the the tympanic membrane

Autoimmune Hemolytic Anemia

Due to the formation of IgM antibodies that agglutinate when exposed to cold temperatures.

Hyponatremia

Due to a syndrome of inappropriate antidiuretic hormone (SIADH), which causes excess water to get reabsorbed by the kidneys.

Chlamydia psittaci

bacteria that causes fungal pneumonia which can infect birds

Histoplasmosis

Fungal pneumonia tend to occur in certain geographic areas is called?

Itraconazole

For both Histoplasmosis and Blastomycosis, individuals are treated with _________ for mild cases

Amphotericin B

For both Histoplasmosis and Blastomycosis, individuals are treated with _________ for disseminated cases

aspiration pneumonia

Food or liquid is breathed into the airways of lungs, instead of being swallowed. Typically occurs among those with an impaired swallowing mechanism (e.g., intoxicated w/ alcohol, Neurological dysfunction such as stroke)

Diagnostic Thoracentesis

A sample of the pleural fluid is taken by inserting a needle through the chest wall.

empyema

-occurs when bacteria have invaded the pleural space -Often loculated and full of bacteria, pus, and adhesions -Positive gram stain & culture -pH < 7.20 Glucose < 60 mg/dL

Pneumococcal Polysaccharide Vaccine (PPSV23)

vaccine that covers 23 types of Streptococcus pneumoniae

13-Valent Pneumococcal Conjugate Vaccine (PCV13)

vaccine that covers 13 types of Streptococcus pneumoniae

Corynebacterium diphtheriae

- green clumped-shaped bacteria with metachromatic granules that causes diphtheria -arranged in a characteristic pattern that resembles Chinese letters

dyphtheria

- an infection with a characteristic tough leathery membrane that forms in the pharynx - aerobic, doesn't form spores

FALSE; B subunit

[TRUE OR FALSE] The A Subunit, the bigger portion of the DT complex, helps in binding to the cell membrane.

Nerve demyelination

destroy the myelin sheath covering the nerve axons leading to polyneuropathy

TRUE

[TRUE OR FALSE] In cutaneous diphtheria, there are typically chronic skin ulcers (shallow)

OCULOMOTOR NERVE PALSY

Inability to move eyes up and down and side to side

Elek's Test

Diagnostic test that is used to tell if the positive strain is toxigenic; C. diphtheriae is grown on an agar plate embedded with antitoxin impregnated filter paper.

pertussis

contagious infection caused by the bacteria, Bordetella pertussis, which causes violent coughing spells called paroxysms, making it difficult to breathe.

Bordetella pertussis

- A gram negative coccobacilli - bacteria that can cause pertussis - releases toxins which are proteins that help the bacteria in various ways to attach to and damage the respiratory epithelial cells

-Filamentous hemagglutinin -Pertactin -Agglutinin

3 toxins which help to anchor bordetella pertussis to the epithelia where it remains during an infection

Pertussis toxin

- Causes an increase in the absolute lymphocyte level in the blood (specifically an increase in the population of T cells floating around through a few mechanisms) - It stimulates T cells to divide, causing them to leave the spleen and thymus, and enter circulation. It also blocks them from leaving the blood and migrating into tissues

Adenylate cyclase toxin

blocks the phagocyte from getting to the site of infection and prevents them from being able to kill the bacteria that they do manage to engulf once they arrive

FALSE; 1-6 weeks

[TRUE OR FALSE] Paroxysmal Phase in pertussis lasts for another 2 weeks.

Macrolide antibiotics (azithromycin)

antibiotic used for pertussis when the bacteria is still alive in catarrhal phase

human rhinovirus

A communicable infectious virus that causes inflammation of the nasal mucosa (rhinitis)

Rapid influenza diagnostic tests

diagnostic test for influenza which can detect viruses in minutes

Neuraminidase inhibitors

treatment for influenza which inhibits neuraminidase

M2 proton channel inhibitors

- Prevents replication and prevents virus from complicating from the host cell - It is found that the virus M2 gene mutates frequently, allowing it to become resistant to the M2 proton channel inhibitors.

Guillain-barre syndrome

Autoimmune disorder of peripheral nervous system is a side effect associated with influenza vaccine

FALSE; must be done before flu season starts

[TRUE OR FALSE] Vaccination must be done every year during flu season to ensure protection