Exam #2 Flashcards
Streptococcal Pharyngitis (Strep throat)
-Pathogen: Streptococcus pyogenes
-Signs: Inflammation/redness in throat, pus on tonsil
-Can spread to LRS causing laryngitis and bronchitis
Streptococcal Pharyngitis complications
-Acute Glomerulonephritis or rheumatic fever
Scarlet Fever
-Caused by: Streptococcus w/ lysogenic phage
-Produces rash on chest/spreads to the body, strawberry red tongue
Streptococcal Respiratory Diseases-Types
-Streptococcal Pharyngitis/complications and Scarlet fever
Streptococcal Respiratory Diseases: Pathogen/Virulence Factors
1.Streptococcus pyogenes (Group A streptococci)
-M protein, Hyaluronic acid capsule, pyrogenic toxins, streptolysin O, Streptokinases, C5a pepsidase
2. Streptococcus equisimilis (Group C streptococci)
-Rarely causes phayngitis
Diphtheria
-Fluid thickens into a Pseudomembrane
-Pathogen: Corynebacterium diphtheriae
-Virulence factors: AB toxin
-Transmission: Respiratory droplets or skin contact
-Dx/Treatment: Elek Test/Anti-toxin
Rhinosinusitis
-Streptococcus Pneumoniae (MC bacterial cause)
-Pain and inflammation of the sinuses and nasal passages
-Headache, malaise, inflammation of nasal mucosa
-More common in adults than kids
Otitis Media
-Painful ear, impaired heading, delayed speech
-If ear drum ruptures, pain suddenly goes away
-More common in kids than adults
Pathogens for Rhinositis and Otitis Media
-Streptococcus pneumoniae
-Staphylococcus aureus
-Haemophilus influenzae
-Moraxella catarrhalis
-Streptococcus pyogenes
Most common bacterial cause of rhinosinusitis
Streptococcus pneumoniae
Bacterial diseases of the upper respiratory system
Streptococcal Respiratory diseases (Streptococcal pharyngitis/complications, scarlet fever), Diphtheria, Rhinosinusitis, Otitis Media
Viral Diseases of the upper respiratory system
-Common cold
Common Cold
-Signs: Sneezing, rhinorrhea, congestion, sore throat
-Pathogens: Enterovirus (family Picornavridae)
Which of the following types of viruses does not cause the common cold?
Select one:
a. Enteroviruses
b. Adenoviruses
c. Coronaviruses
d. Reoviruses
e. Herpes viruses
e. Herpes viruses
Herpes viruses are not known to cause URS infections–they can cause skin infections, mononucleosis, and meningitis
Which population is currently receiving the adenovirus vaccine in order to prevent outbreaks?
Select one:
a. HIV/AIDS patients
b. The elderly
c. Infants
d. Military recruits
d. Military recruits
The term rhinovirus, although still commonly used, is no longer an official taxonomic term. To which type of viruses do the rhinoviruses belong?
Select one:
a. Paramyxoviruses
b. Enteroviruses
c. Reoviruses
d. Coronaviruses
b. Enteroviruses
Serotypes of which viruses that causes the common cold is also known to cause pharyngitis?
Select one:
a. Coronaviruses
b. Enteroviruses
c. Adenoviruses
d. Paramyxoviruses
c. Adenoviruses
Which of the following can be caused by normal microbiota of the URS?
Select one:
a. Common cold
b. Otitis media
c. Rheumatic fever
d. Diphtheria
b. Otitis media
Which of the following Streptococcus pyogenes virulence factors interferes with phagocytosis?
Select one:
a. M protein
b. Streptokinases
c. Streptolysin O
d. Pyrogenic toxins
a. M protein
Scarlet fever is a complication of what?
Select one:
a. Salmonella
b. pertussis
c. strep throat
d. tuberculosis
e. influenza
c. strep throat
Why do most viruses that cause upper respiratory system infections not cause infections in the lower respiratory tract?
Select one:
a. Because there are more dendritic cells in the lower respiratory tract, so the 3rd line of defense is alerted faster.
b. Because they are too large and they cannot enter the alveoli.
c. Because the temperature in the lower respiratory system is to high and does not match the optimal temperature of
reproduction of these viruses.
d. Because the receptor on the host cells is not found in the lower respiratory
c. Because the temperature in the lower respiratory system is to high and does not match the optimal temperature of
Which of the following is NOT part of the upper respiratory system (URS)?
Select one:
a. Pharynx
b. Eustachian tube
c. Larynx
d. Uvula
c. Larynx
The uvula is the URS structure closest to the lower respiratory system
A pseudomembrane obstructing the airway is indicative of?
Select one:
a. coronavirus
b. pertussis
c. diphtheria
d. thrush
e. SARS
c. diphtheria
Bacterial Pneumonia
-Inflammation of lungs, alveoli and bronchioles (gas exchange)
-Caused by bacterial-more serious, viruses or fungi
-Differentiated by: affected region of the lung, organism causing it, location of acquisition
Pneumoccoccal Pneumonia
-Etiologic Agent: Streptococcus Pneumoniae
-Symptoms: Rust or pink colored sputum
-Pathogenesis: Airborne droplets, autoinoculation
-Most common type of bacterial pneumonia (85%)
-Most common in fall and winter
-Vaccine recommended for children (<2 years) and older adults (>65 years)
Primary Atypical Pneumonia
-Also called mycoplasmal pneumonia or walking pneumonia
-Pathogen: Mycoplasma pneumoniae
-Leading type of pneumonia in high school and college students
-Pathogenesis: Binding at the base of the cilia
-Transmission: Inhalation/close contact
-Treatment: Antimicrobials
Klebsiella Pneumonia
-Pathogen: Klebsiella pneumoniae (Opportunistic)
-Symptoms: Thick bloodly sputum and recurrent chills *
-Transmission: Inhalation
-Can cause mortality if untreated
-Gram negative bacteria are the leading cause of nosocomial infections
Other Bacterial Pneumonias
Haemophilus influenzae, Staphylococcus aureus, pneumonic plague, chlamydias
Legionnaires Disease
-Pathogen: Legionella pneumophila
-Symptoms: Rapid decline of lung function, pleurisy
-Pathogenesis: Intercellular parasite of protozoa (amoebae)
-Transmission: Inhalation and aerosolized water
-Epidemiology: Can survive heat and chlorination, at greater risk in smokers, elderly, patients with resp disease
-Treatment: Antibiotics; 50% of patients die if untreated
Tuberculosis
-Breathing difficulty, fatigue, malaise, weight loss…
-Pathogen: Mycobacterium tuberculosis*
-Virulence Factors: Mycolic acid(Prevents lysis), cord factor
-Pathogenesis: Primary TB (lower lobes)-Granuloma (After 3 months), secondary TB (higher lobes), disseminated TB
-A very common disease, leading disease killed in world
-Prevention: Vaccine (can’t be used in immunocompromised)
Pertussis
-Pathogen: Boratella pertussis*
-Symptoms: Severe cough starts after 1-2 weeks, patient may develop cyanosis,
-Virulence factors: Filamentous agglutinin, petussis toxin, others
-Pathogenesis: Petussis toxin* (triggers more receptors for filamentous hemagglutinin)
-Transmission: Highly contagious through respiratory droplets
-Life threatening in children <5 years
Inhalation Anthrax
-Pathogen: Bacillus anthracis*
-Virulence factors: Capsule, anthrax toxin
-Contracted from infected animals via inhalation of endospores
-Tx: Penicillin/Vaccine for military personnel
Influenza
-Sudden high fever, pharyngitis, congestion, dry cough, malaise, headache, myalgia
-Pathogens: Influenzavirus A and B, Antigenic drift-Seasonal epidemics, antigenic shift*-more likely to cause mortality (less common)
-Transmission: Airborne droplets, person-to-person contact, contaminated fomites
Coronavirus Respiratory Syndrome
-Signs/Symptoms: High fever, shortness of breath, malaise body aches, diarrhea
-Pathogen: Coronaviruses*
-Transmission: Respiratory droplets/adhere to lungs, can spread via blood
-Treatment: Vaccines
RSV
-Signs/symptoms: Croup-Barking cough, difficulty breathing
-Leading cause of bronchitis
-Pathogen: RSV (respiratory syncytial virus)
-Transmission: Person to person-most common, respiratory droplets
-Virus triggers formation of syncytia*
-Treatment: Soap/water/disinfectants
Hantavirus Pulmonary Syndrome (HPS)
-Fever, fatigue, muscle aches, some headache, chills, GI symproms,
-50% fatality rate d/t pneumonia and shock
-Pathogen: Hantavirus*
-Disease is contracted by inhalation of dried mouse urine, feces or saliva containing the virus*
-Transmission: Enters blood following inhalation
Fungal disease of the LRS
-Coccidiodomycosis, blastomycosis, histoplasmosis
Mycoses of the LRS
-Coccidiomycosis, Blastomycosis, Histoplasmosis
-Acquired through the inhalation of fungal spores in environment
Coccidiomycosis
-Pathogen: Coccidiodes immites* and C.Posadasii*
-Valley fever; Southwestern US/Northern Mexico
-May have diffuse rash on trunk
Blastomycosis
-Pathogen: Blastomyces dermatidis*
-Southeast US to Canada
-Cutaneous form causing painless lesions on face and upper body
Histoplasmosis
-Pathogen: Histoplasma capsulatum*
-Spelunkers Disease; East US
-Most commonly asymptomatic; In AIDS patients enlarged spleen and liver, type I hypersensitivity
Bacterial infections of the LRS
Bacterial pneumonia, Legionnaires disease, tuberculosis, pertussis, inhalation anthrax
First and second line of defence in LRS
Cilated mucous membrane lines trachea/bronchi/bronchioles, alveolar macrophages, IgA in mucus
Viral Diseases in LRS
Influenza, Coronavirus respiratory syndrome, RSV, Hantavirus
Infectious Diseases of the Digestive System
Peptic ulcer disease, Bacterial gastroenteritis, Staphylococcal food poisoning
Peptic Ulcer Disease
-Signs/Symptoms: Severe abdominal pain* (usually end up in the ER), nausea, vomitting, heart burn, chest pain, black tar-like stool*
-Pathogen: Helicobacter pylori*
-Transmission: Fecal-oral route
-Virulence Factors: Protein that inhibits HCl production, urease (breaks down urea, producting ammonia)
-Treatment: Antimicrobials, proper food handling, sewage treatment/water purification
-Studies show that this could lead to esophageal cancer
Shigellosis (Bacterial Gastroenteritis)
-Signs/symptoms: Fever, abdominal cramps, bloody stool
-Pathogen: Shigella (four species)
-Virulence Factors: Enterotoxins(diarhhea), Shiga toxin(stops protein synthesis to host cells)*, type III secretion system
-Epidemiology: 165 mil cases/year
-Transmission: poor sanitation (fecal-oral route)
Traveler’s Diarrhea (Bacterial Gastroenteritis)
-Pathogen: Enterotoxigenic strains of Escherichia Coli*
-Virulence Factors: Fimbriae, adhesions, shiga-like toxin (caused RBC lysis, can lead to kidney failure), EHEC
-Epidemiology: 0157: H7 found in up to 50% of beef carcasses in US
Campylobacter Diarrhea (Bacterial Gastroenteritis)
Most common bacterial gastroenteritis in US
-Signs/symptoms: Bleeding lesions in jejunum, ileum, and colon
-Pathogen: Campylobacter jejuni*
-Epidemiology: Chickens (81%), common in other fowl, birds, water
-Can cause: IBS, arthritis, Guillain-Barre syndrome
-Prevention: Clean contaminated kitchen surfaces, cook food to proper temperature (>165 degrees), avoid beaches
C. Diff Diarrhea
-AKA: antimicrobial-associated diarrhea
-Signs/Symptoms: Clear, watery, foul-smelling bowel movements/day, Can escalate to psendomembranous colitis (highly inflammatory intestinal lesions)*
-Pathogen: Clostridium difficile*
-Pathogenesis: Antimicrobials can kill good bacteria
-Virulence Factors: AB Toxin
-Treatment: Use of probiotics (Lactobacillus), fecal transplants; NO ANTIDIARRHEAL meds
Bacterial Gastroenteritis (Food poisoning)
-Inflammation of stomach or intestines, caused by bacteria
-Transmission: Poorly prepared foods, contaminated water, poor living conditions
-Signs/symptoms: Quick abdominal pains/cramps, can lead to vomitting, diarrhea, loose stools-dysentery
-Common
-Diagnosis: Fecal smear, nucleic acid tests
-Treatment: Usually go away on their own
-Prevention: Proper handling of food: Washing raw food, cooking temperature, washing hands and utensils…
Salmonellosis
-Pathogen: Salmonella enterica, found in intestines in most vertebrates, >2500 serotypes/strains
-Virulence factors: Resistant to stomach acid, type III secretion system
-Pathogenesis: Eating of cooking with contaminated egg
-Self limiting within a week
Typhoid Fever
-Pathogen: Salmonella enterica, found in intestines in most vertebrates, >2500 serotypes/strains
-Virulence factors: Resistant to stomach acid, type III secretion system
-Pathogenesis: Food or water contaminated with feces from a carrier of S. Enterica Typhi or Paratyphi
-Asymptomatic; can affect spleen, bone marrow, gall bladder
-Treated by antibiotics
Cholera
-Pathogen: Vibrio cholerae; caused by specific strains such as O139, environment of the human body
-Virulence Factors: Cholera toxin (AB toxin), stimulates cell to secrete elecrolytes and promotes water loss; dehydration, thirst, metabolic acidosis, death-poor access to sanitation
-Signs/Symptoms: “Rice-water” diarrhea
-Prevention: Access to clean water/sanitation, boiling of water, properly cooking fish
Bacterial Intoxication
-Food poisionings caused by toxins, microbe itself may not be present
-Signs/symptoms: Short incubation time, nausea, vomiting, diarhhea, abdominal cramping, discomfort, bloating, loss of appetite, fever
Staphylococcal food poisioning
Pathogen: Staphylococcus aureus*
-Common Foods: Processed meats, custard pastries, potato salad, ice cream
-Virulence factors: Heat-stable enterotoxins, Salt-tolerance
Which of the following conditions has the shortest incubation time (a few hours)?
Select one:
a.E. coli O157:H7
b.Cholera
c.Shigellosis
d.Campylobacter diarrhea
e.Staphylococcal food poisoning
e.Staphylococcal food poisoning
Source of infection: Salmonellosis
Reptiles
Source of infection: E. coli O157:H7
Beef
Source of infection: Cholera
Contaminated Water
Source of infection: Staphylococcal food poisoning
Potato Salad
Which of the following is considered a healthcare associated infection?
Select one:
a.C. diff diarrhea
b.Cholera
c.E. coli O157:H7
d.Shigellosis
e.Typhoid fever
a.C. diff diarrhea
The order of magnitude of the number of bacterial cells in the lower small intestine and colon is _____________.
Select one:
a.quadrillions
b.trillions
c.billions
d.millions
b.trillions
What is the etiologic agent of traveler’s diarrhea?
Select one:
a.Staphylococcus aureus
b.Salmonella enterica
c.Campylobacter jejuni
d.Shigella sonnei
e.Escherichia coli
e.Escherichia coli