Chapter 1.11 Haemophilus, Bordetella, And Legionella

Question 1

What are the gram-negative rods?

Answer 1

Haemophilus influenzae, Bordetella pertussis, and Legionella pneumophilia
*grouped together because they are acquired though the respiratory tract

Question 2

What is the meaning of haemophilus influenzae?

Answer 2

Haemophilus- “blood loving”- this organism requires blood-containing medium for growth
Influenzae- attacks people with viral influenza infection

Question 3

What type of organism is haemophilus influenzae?

Answer 3

Obligate human parasite transmitted via respiratory route

Question 4

What are the major subtypes of haemophilus influenzae?

Answer 4

A, b, c, d, e, f

• type b is associated with invasive Haemophilus influenzae disease in children such as meningitis, epiglottitis, and septic arthritis
• capsule b = bad

Question 5

What patients have frequent infections with nontypeable H. Influenzae?

Answer 5

COPD patients which then get worsening of wheezing, shortness of breath, and cough

Question 6

What is the most serious infection caused by encapsulated haemophilus influenzae?

Answer 6

Meningitis- caused by type b

Question 7

What is the clinical presentation of an infant with meningitis from haemophilus influenzae type b?

Answer 7

Nonspecific signs- fever, vomiting, and altered mental status

Question 8

What are the 3 bacteria responsible for most meningitis acquired by the baby coming out the birth canal?

Answer 8

Listeria monocytogenes, E.coli, and Group B Streococus

Question 9

What 2 bacteria cause meningitis later in life of an infant (6mo.-2 years)?

Answer 9

Neisseria meningitides and Haemophilus influenzae

Question 10

How does Haemophilus influenzae cause acute epiglottitis?

Answer 10

H. Influenzae type b amuses rapid swelling of the epiglottis, obstructing the respiratory system and esophagus.

Question 11

What is the clinical presentation of a child with acute epiglottitis from Haemophilus influenzae?

Answer 11

Sore throat, fever, severe upper airway wheezing (stridor), excessive saliva out of mouth, and unable to swallow

Question 12

What organism is the most common cause of septic arthritis in infants?

Answer 12

Haemophilus influenzae type b

Question 13

What is affected with septic arthritis caused by Haemophilus influenzae?

Answer 13

Single joint is usually affected

Question 14

What is the clinical presentation septic arthritis from Haemophilus influenzae?

Answer 14

Infant with fever, pain, swelling, and decreased mobility of the joint

Question 15

What does a gram stain show for septic arthritis from Haemophilus influenzae?

Answer 15

Pleomorphic gram-negative rod

Question 16

What is the clinical presentation of children with sepsis from Haemophilus influenzae?

Answer 16

Fever, lethargy, loss of appetite, and no evidence of localized disease

Question 17

What is the most important organ in fighting off infection by encapsulated bacteria?

Answer 17

Spleen

Question 18

What disease is caused from Haemophilus ducreyi?

Answer 18

Sexually transmitted disease called chancroid

Question 19

What is the clinical presentation of a patient with chancroid from Haemophilus ducreyi?

Answer 19

Painful genital ulcer, unilateral painful inguinal lymph node that could rupture and release pus

Question 20

What organism causes syphilis?

Answer 20

Treponema pallidum

Question 21

How is an ulcer from syphilis different than an ulcer from Haemophilus ducreyi?

Answer 21

Syphilis ulcer- painless and associated with bilateral, painless, and nonsupperlative (no pus)
Haemophilus ducreyi ulcer- painful genital ulcer

Question 22

What is the organism that causes herpes?

Answer 22

Herpes simplex virus 1 and 2

Question 23

What is the clinical appearance of herpetic lesions?

Answer 23

Blisters that can rupture and be painful

Usually accompanied by systemic symptoms of myalgias and fevers

Question 24

What is the difference between chancroid and herpes lesion?

Answer 24

Chancroid does not produce systemic symptoms

Herpes- does produce systemic symptoms

Question 25

What are the characteristics of lymphogranuloma venereum?

Answer 25

Painless matted suppurative, slow developing inguinal lymph nodes *also called chlamydia trachomatis

Question 26

What would be included in a differential diagnosis if a patient has matted lymph notes that will rupture?

Answer 26

Syphilis, herpes, and lymphogranuloma venereum

Question 27

What Haemophilus species grow slowly and can cause endocarditis?

Answer 27

H. Parainfluenzae, H. Aphrophilus, H. Paraphrophilus

Question 28

What group is Haemophilus species included in?

Answer 28

``` HACEK Haemophilus species Actinobacillus species Cardiobacterium species Eikenella species Kingella species ```

Question 29

What disease does Gardnerella vaginalis cause?

Answer 29

Bacterial vaginitis with anaerobic vaginal bacteria

Question 30

What is the clinical presentation of a woman infected with Gardnerella vaginalis?

Answer 30

Burning or pruritis of the labia, burning on urination, foul smelling vaginal discharge that has a fishy odor

Question 31

How can Gardnerella vaginalis be differentiated from other causes of vaginitis?

Answer 31

The presence of clue cells on a slide of vaginal discharge

Question 32

What are clue cells?

Answer 32

Vaginal epithelial cells that contain pleomorphic bacilli within the cytoplasm *in Gardnerella vaginalis cells

Question 33

What disease is caused by Bordetella pertussis?

Answer 33

Whooping cough

Question 34

What are the 4 virulence factors of Bordetella pertussis?

Answer 34

Pertussis toxin, extra yo plasmin adenylate Cyclades, filamentous hemagglutinin, and tracheal cytotoxin

Question 35

How is whooping cough transmitted?

Answer 35

Via respiratory secretions on the hands or in aerosolized form

Question 36

What are the 3 stages of whooping cough?

Answer 36

1. Catarrhal stage 2. Paroxysmal stage 3. Convalescent stage

Question 37

What occurs in the catarrhal stage of whooping cough?

Answer 37

Low-grade fever, runny nose, sneezing, mild cough * disease is contagious * lasts 1-2 weeks

Question 38

What occurs in the paroxysmal stage of whooping cough?

Answer 38

Fever subsides Bursts of nonproductive cough (15-25/day) May be hypoxemic, cyanotic, eyes bulge, neck veins engorge Vomiting *lasts a month or longer

Question 39

Who is whopping cough most common in?

Answer 39

Infants less than 6 months | Infants and young children more than 6 months who require hospitalization

Question 40

What is one of the manifestations of the pertussis toxin?

Answer 40

Increased number of lymphocytes but only slight increase in neutrophils

Question 41

What occurs during the convalescent stage of whopping cough?

Answer 41

Coughing attacks are less frequent and the patient is no longer contagious

Question 42

What medium is used to assess Bordetella pertussis?

Answer 42

Bordet-Gengou medium (potato, blood, and glycerol)

Question 43

What is the vaccination used for Bordetella pertussis?

Answer 43

DTaP | Diphtheria-Tetanus-accellular Pertussis

Question 44

What are the characteristics of Legionella pneumophila?

Answer 44

Aerobic gram-negative rod | Ubiquitous in natural and man made water environments

Question 45

How is legionella pneumophila transmitted to humans?

Answer 45

Aerosolized contaminated water is inhaled, resulting in infection Ex. Air conditioners, whirlpools, shower heads that make mist in supermarkets

Question 46

T/F Legionella pneumophila is a facultative intracellular parasite

Answer 46

T - it settles in the lower respiratory tract but survives and replicates intracellularly in macrophage

Question 47

What are the 2 unique things about Legionella?

Answer 47

1. Is a facultative intracellular parasite for free living amoebas 2. Can enter low metabolic state and survive in biofilm

Question 48

What diseases are associated with Legionella?

Answer 48

Pontiac fever and Legionnaires' disease

Question 49

What are the clinical manifestations of Pontiac fever caused by Legionella?

Answer 49

Headache, muscle aches, fatigue, followed by fever and chills *strikes suddenly and resolves in a week

Question 50

What are the clinical manifestations of Legionnaires' diseases from Legionella?

Answer 50

High fever and severe pneumonia

Question 51

What disease is commonly caused by Legionella pneumophila?

Answer 51

Community acquired pneumonia

Question 52

What are the unique manifestations of community acquired pneumonia from legionella pneumophilia?

Answer 52

Fever with pulse-temperature dissociations (high fever, low HR), severe headache, confusion, myalgia, rhabdomylosis, cough, hyponatremia, hypophosphatemia, elevated liver enzymes (AST, ALT, LDH)