Lower Respiratory Tract Infections

Front 1

Name the common infections of the lower respiratory tract. (5)

Back 1

Bronchitis
Bronchiolitis
Influenza
Pertussis
Pneumonia

Front 2

What mechanisms does our body employ to fight off respiratory infections?

Back 2

1.) Alveolar macrophages
2.) Complement components
3.) Surfactant lining of alveoli
4.) Phospholipids
5.) IgE, IgG, IgA and Factor B
6.) B and T cells that can illicit response to infections

Front 3

What are some mechanisms used by bacteria to avoid phagocytosis?

Back 3

1.) capsule production
2.) toxin production
3.) large size
4.) replication inside cells of host
5.) mimicry of host cells

Front 4

What is the cause of bronchitis? (bacterial or viral) and name some of the causative agents.

Back 4

Usually caused by VIRAL agents, some potential causes are influenza viruses A and B, parainfluenza virus, adenovirus, RSV, rhinovirus, coxsackie A and B virus.

Front 5

In what age groups do you usually seen bronchitis?

Back 5

Can be all ages, but most common in younger and older persons

Front 6

What is the common presentation of bronchitis?

Back 6

Starts with non-productive cough (may become productive later), chest pain, and fever of 101-102, malaise, headache, sore throat.

Front 7

What will chest x-ray show in bronchitis?

Back 7

Normal findings, therefore it can be useful to distinguish pneumonia from bronchitis

Front 8

What is the diagnosis of bronchitis based on?

Back 8

Patient symptoms and clinical signs

Front 9

What is the treatment for bronchitis in an otherwise healthy person?

Back 9

Supportive treatment

Front 10

What is the most common cause of Bronchiolitis?

Back 10

RSV

Front 11

What age group is most likely to get bronchiolitis?

Back 11

Infants younger than one year old

Front 12

What are the symptoms of bronchiolitis?

Back 12

Early sx include rhinorrhea, cough, and low grade fever, may also include tachypnea and tachycardia, diffuse expiratory wheezing, inspiratory crackles, nasal flaring, vomiting, cyanosis, and hyperinflation of the lungs.

Front 13

What are risk factors for getting bronchiolitis?

Back 13

Younger than 6 months of age, bottle feeding, prematurity, exposure to cigarette smoke, and crowded living conditions

Front 14

How is bronchiolitis diagnosed?

Back 14

Patient symptoms and clinical signs, use chest x-ray to rule out pneumonia, and can do antigen testing for RSV from nasal washings

Front 15

Of the 3 types of Influenza virus, which is most mild?

Back 15

Influenza C

Front 16

What are the symptoms of influenza?

Back 16

Abrupt onset of fever (102-104), chills, rigors, headache, congested conjuctiva, extreme prostration with myalgia in back and ribs, and NONPRODUCTIVE COUGH

Front 17

In some patients influenza can lead to a secondary bacterial pneumonia infection---what are the main bacteria that cause this secondary infection? (4)

Back 17

1.) Strep. pneumo
2.) Strep. pyogenes
3.) H. infleunzae
4.) Staph. aureus

Front 18

How do you diagnose influenza?

Back 18

Definitive diagnosis requires lab testing, and include direct antigen detection tests, or rRT-PCR

Front 19

What are good ways to differentiate the flu from the common cold or atypical pneumonia?

Back 19

Atypical pneumonia is a gradual process, the flu develops rapidly. As for the cold, the common cold shouldn't cause a fever, whereas the flu will cause fever

Front 20

What is the treatment for influenza?

Back 20

Supportive care

Front 21

What is antigenic shift and antigenic drift? Which influenza viruses undergo which?

Back 21

Antigenic shift is major changes that can occur with influenza A because it has multiple reservoirs--both humans and other hosts. Antigenic drift is small changes (the reason we need a new vaccine every year) and is seen in Influenza B and C because their only host is humans

Front 22

What is the common name for pertussis?

Back 22

Whooping cough

Front 23

What is the causative agent of pertussis?

Back 23

Bordetella pertussis

Front 24

What type of bacteria is B. pertussis?

Back 24

Gram Negative Cocco-Bacilus

Front 25

What are symptoms of pertussis?

Back 25

paroxysms of coughing, and inspiratory "whoop", low grade fever. Vomiting can sometimes occur after a coughing attack

Front 26

What toxin does pertussis release? Which part does the binding, which part contains the toxin?

Back 26

AB toxin
B subunit for binding
A subunit for toxin

Front 27

How do you diagnose pertussis?

Back 27

Need lab procedures using nasopharyngeal aspirates plated on Bordet-Gengou medium, or can do immunofluorescent stains on nasal secretions for the bacteria or ELISA tests

Front 28

If you do a blood draw on a patient with pertussis, what type of WBC is elevated? How does this differ from most bacterial infections

Back 28

See elevated lymphocytes on blood draw, which is different from most infections where you see an increase in neutrophils

Front 29

What antibiotic is useful for pertussis? Is it helpful to give at any point of the infection?

Back 29

Erythromycin is the drug of choice, but it is only helpful in the first stage of infection and won't help shorten the infection once it's entered it's second stage

Front 30

What is the clinical presentation of typical pneumonia?

Back 30

SUDDEN onset of chills, fever, dyspnea, and productive cough with purulent sputum (which may be blood tinged), pleuritic chest pain. On physical exa, see fever, tachypnea, tachycardia, and crackles on lung exam

Front 31

What does the chest x-ray show in typical pneumonia?

Back 31

Consolidation

Front 32

What are the major causes of pneumonia and which is MOST common?

Back 32

Major causes include: strep. pneumo, klebsiella pneumo, H. infleunzae, Moraxella catarrhalis, and Staph. auereus. The MOST common is strep. pneumo

Front 33

What is the clinical presentation of atypical pneumonia?

Back 33

GRADUAL onset of non-productive cough and dyspnea, the extrapulmonary signs may be more prominent, such as headache, sore throat, and diarrhea

Front 34

What does the chest x-ray show in atypical pneumonia?

Back 34

Patch or interstitial infiltrates with no signs of consolidation

Front 35

What are the major causes of atypical pneumonia?(3)

Back 35

1.) Mycoplasma pneumonia "walking pneumo"
2.) Chlamydia pneumonia (in young adults)
3.) Legionella pneumonia ( may occur in healthy or immunocompromised and can be quite severe)

Front 36

Which pneumonia is most common in HIV patients?

Back 36

Pneumocystis jirovecii

Front 37

What illnesses does parainfluenza virus cause?

Back 37

In children croup and pneumonia. In adults the common cold

Front 38

Influenza and Parainfluenza virus use HA and NA, what are these and what do they do?

Back 38

HA = viral hemagglutin: helps hold onto cells
NA= neurominidase permits viral spread

Front 39

How is parainfluenza virus diagnosed?

Back 39

Patient symptoms and lab confirmation through hemaglutination activity from respiratory secretions or serology for anti-HA antibodies

Front 40

What is the treatment for croup caused by parainfluenza virus?

Back 40

Supportive care and corticosteroids if needed to help with breathing

Front 41

What do rhinoviruses cause?

Back 41

The common cold

Front 42

Which virus binds to ICAM-1 on upper respiratory tract epithelial cells?

Back 42

Rhinovirus

Front 43

What is the viral cause of hand-foot-mouth disease?

Back 43

Coxsackie A virus, primarily

Front 44

What is the clinical presentation of someone infected with adenovirus?

Back 44

Respiratory tract infection (common cold), conjuctivitis, hemorrhagic cystitis, and gastroenteritis

Front 45

How does the adenovirus spread?

Back 45

Aerosol, fecal-oral, or direct contact

Front 46

How is adenovirus diagnosed?

Back 46

Either isolate virus in cell culture or do serology

Front 47

What group gets the adenovirus vaccination?

Back 47

The military

Front 48

What are some of the complications that can come from Strep. pyogenes pharyngitis infection?

Back 48

1.) Glomerulonephritis
2.) Rheumatic Fever
3.) Scarlet Fever (if bacteria is infected with phage)

Front 49

What virulence factors does Strep. pyogenes use to cause infection?

Back 49

1.) Streptokinase (converts plasminogen --> plasmin [fibrinolysis])
2.) M protein (resists phagocytosis)
3.) Hyaluronidase (breaks down connective tissue)
4.) DNase (breaks down DNA)

Front 50

What kind of bacteria is strep. pyogenes?

Back 50

Gram Positive Cocci, Beta-hemolytic, Bacitracin Sensitive, ASO+, Anti-Streptolysin O antibodies would be present in the patient's serum if infected

Front 51

What is the treatment for infection with Strep. pyogenes?

Back 51

Penicillin G

Front 52

What group of people are typically diagnosed with Moraxella catarrhalis pneumonia?

Back 52

Patients with COPD. It's the second most common cause behind H. influenza

Front 53

What virulence factors does Moraxella catarrhalis use to establish infection?

Back 53

1.) pili (used for attachment)
2.) antigenic variation (to avoid host immune response)
3.) endotoxin
4.) capsule

Front 54

What is the clinical presentation for a person infected with Moraxella catarrhalis?

Back 54

Otitis media, sinusitis, or pneumonia

Front 55

What kind of bacteria is Moraxella catarrhalis?

Back 55

Gram Negative, Aerobic, Oxidase Positive

Front 56

How is Moraxella catarrhalis diagnosed?

Back 56

Through biochemical features
1.) hydrolyzes tributryin
2.) produces DNase
3.) reduces nitrite and nitrate
4.) can't ferment sucrose, glucose, maltose, or lactose

Front 57

What is the treatment for Moraxella catarrhalis?

Back 57

Amoxicillin-clavulanate, second and third generation celphalosporins, or TMP-SMX

Front 58

What does it mean for a bacteria to be Quellung positive?

Back 58

The Quellung reaction is a biochemical reaction in which antibodies bind to the bacterial capsule of Streptococcus pneumoniae, Klebsiella pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Escherichia coli, and Salmonella. The antibody reaction allows these species to be visualized under a microscope. If the reaction is positive, the capsule becomes opaque and appears to enlarge.

Front 59

How is the diagnosis of Strep. pneumo infection made? (What are its biochemical features)

Back 59

Gram Positive Diplococci, alpha-hemolytic, catalase negative, optochin sensitive, quellung reaction positive

Front 60

How is infection with H. influenzae diagnosed? (What are it's biochemical features)

Back 60

Gram negative, requires X factor and NAD (V factor) on chocolate agar

Front 61

What is the treatment for infection with H. influenzae?

Back 61

Third generation cephalosporin: Ceftriaxone

Front 62

What is the most common cause of meningitis in newborns?

Back 62

Streptococcus agalactiae

Front 63

What are the biochemical features of Strep. agalactiae?

Back 63

Gram positive, beta hemolytic, bacitracin resistant

Front 64

How is Mycoplasma pneumoniae diagnosed?

Back 64

Presence of cold hemagluttin, no cell wall, fried egg appearance, serology

Front 65

What are the biochemical features of Staph aureus that can aid in diagnosis?

Back 65

Gram positive clusters, catalase positive, coagulase positive

Front 66

Why can you get multiple 'cold' infections in one year?

Back 66

Because there are over 100 different types of rhinoviruses