CRR Pathogens

What immunoglobulin is critical for dealing with respiratory pathogens?

What are the three main purposes of toxins?

How do organisms generally avoid immune clearance?

Extensive inflammation breaks down critical tight junction barriers at the epithelium, preventing effective gas exchange. Inflammation can be triggered in a variety of way. What is one of the most common?

Which type of infection should be treated with antibiotics, viral or bacterial?

What are the two most common causes of Acute Rhinosinusitis?

Are infections of the nasal passages most commonly caused by viruses or bacteria?

Are infections of the pharynx most common caused by viruses or bacteria?

What are two bacterial causes of concern in pharyngitis?

Identify the pathogen:
Gram + cocci
Causes a fever, painful throat, and is sudden in onset
Tonsillopharyngeal erythema, lymphadentitis, petechiae on palate
Rheumatic Fever
Adherence: M protein, Lipoteichoic acid, fibronectin binding protein
Virulence Factors: Hyaluronic Acid Capsule, Hemolysin, Proteases

What adherence factor in Streptococcus pyrogenes is implicated in Rheumatic Fever?

Identify the pathogen:
Gram-positive, aerobic, toxin-producing rod shaped bacterium
Causes sore throat, low-grade fever, membrane on tonsils or pharynx, neck swelling
Low prevalence in US, but continues to be a prob world-wide
Vaccine (DTaP)

What are the virulence factors associated with Corynebacterium diphtheriae?

Corynebacterium diphtheriae causes illness when the organism colonizes the mucosal region of the oropharynx and releases diphtheria toxin. How does this kill cells?

How is infection of Corynebacterium diphtheriae treated?

Disease caused by Corynebacterium diphtheriae progresses when diphtheria toxin is released into the bloodstream. What does this cause?

What is the major cause of Epiglottitis?

What are the two most common causes of bronchitis?

What is the most common infection of the trachea?

Identify the pathogen:
Gram-negative, encapsulated, pleomorphic, fastidious rod, requires heme (Factor X) and NAD (Factor V) for growth
Mulitple serotypes, type B is most common
Epiglottitis and pneumonia
Virulence Factors: polysaccharide capsule, outer membrane protein OMP, Lipooligosaccharide LOS (endotoxin-like), IgA protease
Prevention: vaccine

Haemophilus influenza is normal flora for the human nasopharynx, but appears to colonize humans exclusively. It is highly inflammatory and can trigger a strong, damaging inflammatory response. Growth and detection can be difficult due to the fastidious nature of the organism. A classic hallmark of H. influenza is its requirement for growth media supplemented with _______ and ________?

Haemophilus influenza causes epiglottitis and pneumonia. What are two other diseases, unrelated to the respiratory tract, that this pathogen causes?

Identify the pathogen:
Gram-negative, encapsulated, aerobic, fastidious, coccobacillus
HIGHLY contagious, humans are the only known host
Colonizes trachea and produces multiple toxins
Four stages with different manifestations
Outbreaks every 3-5 years, primarily in children less than 1 year in age
Virulence Factors: Fimbriae, toxins (pertussis toxin, tracheal toxin, adenylate cyclase toxin)

What are the four stages of Bordetella pertussis?

Why is Bordetella pertussis tricky to diagnose and treat?

During the most severe stage of the disease in Bordetella pertussis, the paroxysmal stage, patients can experience coughs so severe that what can result?

What are the two virulence factors associated with Bordetella pertussis?

What 3 toxins are associated with Bordetella pertussis?

What disease should be considered in children and adults with coughs lasting greater than 6 days?

What is the Gold Standard Test for diagnosing Bordetella pertussis?

What does the CDC recommend for diagnosis of Bordetella pertussis?

What are the treatment options for Bordetella pertussis?

Which form of vaccine is used for children as the initial vaccine and booster for pertussis? What is used in older children and adults as boosters?

What are the two most common types of pneumonia seen in children aged 0-1 month?

What are the two most common types of pneumonia seen in children aged 1-6 months?

What are the two most common types of pneumonia seen in children aged 6 months to 5 years?

What are the two most common types of pneumonia seen in people aged 16-30 years?

What are the two most common types of pneumonia seen in older adults?

Identify the pathogen:
Gram-positive, catalase-negative, Optochin sensitive, alpha-hemolytic, encapsulated diplococci
Pneumonia with rapid onset and blood sputum
Most prevalent cause of death due to acute infection in US, 6th leading cause of disease in the US
Polysaccharide capsule is a major part of virulence and the target of current vaccines

Streptococus pneumonia is a serious healthcare problem in hospitalized elderly patients. What are the 3 characteristics that are used to differentiate this from other gram-positive cocci?

Identify the pathogen:
Abrupt onset of fever and chills
Productive blood sputum
Can follow recent viral infections
Primarily targets children
6th leading cause of disease in US
Cause of about 6 million cases of otitis media
Most prevalent cause of death due to acute infection in the US

Streptococcus pneumonia has an antiphagocytic capsule. What does it prevent?

What protease is associated with Streptococcus pneumonia? What toxin is responsible for disrupting the alveolar-capillary boundary?

What 3 cell components are associated with Streptococcus pneumonia?

What pathogen is the following pathogenesis associated with?
Following colonization at site of disease:
-- Capsule prevents phagocytosis
-- PspA blocks complement
-- IgA protease destroys IgA
-- CpbA adheres to cells
-- Ply disrupts barriers
-- Autolysin lysis the organism (release debri causes massive inflammatory response)

What two vaccines are available for streptococcus pneumonia?

What are the treatment options for streptococcus pneumonia?

Identify the pathogen:
Gram-negative, fastidious, aerobic, facultative intracellular pathogen
Legionnaire's disease and atypical walking pneumonia
High mortality rate, few reported cases in the US
Virulence Factors: phospholipase, macrophage infectivity protein, and endotoxin
Pathogenesis-growth to very high numbers in macrophages and stimulation of inflammatory responses
Detection: direct observation of the organism in sputum, antibody reactivity, urine test for circulating antigen

What disease is unusual in combining pneumonia with several other systemic complications including altered liver and renal function along with heightened serum creatinine phosphokinase?

How is Legionnella pneumophila transmitted?

Identify the pathogen:
Gram-negative, aerobic rod with large polysaccharide capsule
Normal flora of upper respiratory tract, enteric and genitourinary tracts
Pneumonia observed in alcoholics following aspiration of this pathogen into lungs
Signs and symptoms include sudden onset, high fever, hemoptysis (currant jelly sputum)
<1% of cases require hospitalization

How is Klebsiella pneumonia generally detected? How can it be prevented? What is the treatment for this pathogen?

Identify the pathogen:
Smallest bacterial genome
No peptidoglycan cell wall
Membrane contains cholesterol like eukaryotes
Normal inhabitants of respiratory tracts
Similar in size to some viruses
Primary cause of walking or "atypical" pneumonia
Usually mild
Upper respiratory tract infection with fever, cough, malaise, and headache
May lead to tracheobronchitis with fever and nonproductive cough
Rare extrapulmonary syndromes, including cardiologic, neurologic, and dermatologic findings
Impacts infants and immunocompromised patients
Occurs most frequently among people who are in close quarters

The virulence factor associated with Mycoplasma pneumonia is an adhesion protein that inhibits ciliary action. It produces hydrogen peroxide and cytolytic enzymes, and triggers a strong proinflammatory response. What is this adhesion protein called?

_______ __________ with respiratory illness is commonly associated with Mycoplasma pneumonia infection.

How is infection with Mycoplasma pneumonia treated?

Identify the pathogen:
Aerobic, acid-fast rods, with high membrane lipid content
Grow very slowly
Resistant to intracellular killing by phagocytes

What are the two respiratory pathogens included in Mycobacteria?

Identify the pathogen:
Acid-fast, aerobic, slow growing, facultative intracellular bacilli, with a unique cell wall -- contains mycolic acid and arabinogalactan in addition to peptidoglycan.
This cell wall allows this pathogen to survive inside macrophages, and makes it impervious to many different antibiotics.
85% of cases are pulmonary, with a slow onset and chronic course.
It originates in the lungs and moves to other regions of the body
This is the most common infectious cause of mortality worldwide
One-third of world's population is infected

What are the two unique features of the cell of wall of Mycobacterium tuberculosis?

Mycobacterium tuberculosis does not produce toxins, so the virulence of this organism is largely determined by its survival in the presence of immune responses and intracellular environment. What is the major virulence factor of M. tuberculosis? What are the other two?

Identify the pathogen:
Collection of activated macrophages surrounding an area of necrosis (caseous necrosis)
CD4+ T-cells, produce cytokines
Mycobacterial antigens persistently activate T-cells in the granuloma
Chronic inflammation and type IV hypersensitivity

What is the most definitive test for detection of Tuberculosis Granuloma?

Which type of viral respiratory infection, upper or lower, is associated with a higher morbidity and mortality?

What are the two most common causes of the common cold in infants and children? In adults?

What are the two most common causes of pharyngitis in infants <1 yr? In children and adults?

What are the two most common causes of laryngitis?

What are the two most common causes of LTB/croup in infants and children? In adults?

What are the two most common causes of Bronchiolitis in infants less than 1 year? (rare in children and adults)

What are the two most common causes of pneumonia in infants less than 1 year? In children? In adults?

What type of virus is the influenza virus?

Which influenza serotype causes the most severe disease (causes pandemics)? It undergoes antigenic shift.

Differences within the type A class of influenza virus are determined by what two things?

In the influenza virus structure, what external protein is the object by which the virus attaches to cells? Antibodies to this neutralize the virus. It attaches to cell sialoglycoproteins and sialoglycolipids. It is the primary target of vaccines. Contains a peptide sequence with fusion activity.

In the influenza virus structure, what is the enzyme that cleaves sialic acid, enhances release, and prevents clustering of the virus or binding by mucous (contains SA)?

In the influenza virus, there are two matrix proteins inside of the envelope. _____ is important in virus assembly. _____ is an ion channel protein involved in controlling internal pH

There are two non-structural proteins in the influenza virus. First is _______, which is produced in cells only, and interferes with cellular antiviral response. Second is ______ -- present in small amounts and functions in transport of viral nucleoproteins, and regulation of viral RNA synthesis.

What does the influenza virus require for replication?

Identify the virus from the clinical presentation:
Typical infection begins with fever, headache, myalgia and malaise, cough and sore throat. Usually improves over 2-5 days, may last for a week or more. May have weakness, fatigability.
Can also result in Reye's Syndrome (liver failure) with increased risk with ASA use -- so aspirin should not be used in childen with this

Antigenic shift is limited to influenza virus serotype _____ only.

What involves point mutations in HA; NA can alter the virus enough that a person's AB from a previous infection may not completely protect them, but results in milder disease. These changes can be in the A or B serotypes.

Does Antigenic Shift involve point mutations in HA, NA, or both?

Does antigenic shift involve changes in the HA, NA or both?

Which can cause full-scale pandemics, antigenic drift or antigenic shift?

What is the main type of influenza vaccine?

What two drugs were previously used to treat active influenza A, but are not used anymore due to resistance? What two drugs work somewhat for both serotypes A and B and are sometimes used?

What type of agents are indicated as prophylaxis in high risk patients who cannot take the influenza vaccine?

In what patients is Zanamavir (a neuraminidase inhibitor to treat influenza) contraindicated for?

Parainfluenza virus 1-4, respiratory syncytial virus, measles, and mumps viruses are all what type of viruses?

Respiratory Syncytial Virus (RSV) is an exception to the structure within the paramyxovirus group. What is the main difference?

Southeast US; symptoms include malaise, weight loss, night sweats, chest pain, hoarseness, fever; bilateral rales; rhonchi; raised verrucous, crusted lesions; multiple nodular lesions; thick-walled, refractile broad-based budding yeast cell; white fluffy fungus; necrosis and cavitation; dimorphic; inhalation; 4-6 week innoculation period; indolent pulmonary inf; opportunistic; can disseminate; KOH preps, culture, serology

Smoker; Central/SA; asymptomatic; CXR = cavitary lesion; S. American blastomycosis; forest workers -- males more bc more male lumberjacks; has receptors for estrogen; dimorphic; inhalation; yeast; chonic granulomatous disease; primary inf is pulmonary, reactivates yrs later, disseminates to buccal, nasal, GI mucosa; mariner's wheel; KOH prep/sputum stain.

Type I diabetes; ketoacidosis; periorbital swelling; mucopurulent postnasal discharge; black ulceration of nasal mucosa; 3rd CN palsy; no improvement w antibiotics; rapidly growing fungus with wide, irregular nonseptate hyphae branching at wide angles; rhizopus spp. and mucor spp., uncontrolled diabetics and leukemics; monomorphic; loves blood vessels; rhinocerebral zygomycosis; destruction of lung parenchyma; grows very rapidly; black fungus in mouth; CT of paranasal sinuses, detect microscopy, biopsy; Ampho B and debridement; high MORTALITY

Leukemic on cytotoxic therapy; chest pain, fever, chills, hemoptosis, resp. distress; bilateral rales; ANC; fungus with septate, acutely branching hyphae; vascular thrombi due to hyphal invasion of blood vessels; catalase +; chronic granulomatous disease and neutropenia; necrotizing pneumonia and aspergilloma (fungus ball); direct microscopy, biopsy; monomorphic; dichotomously branching hyphae

Trouble breathing, fever, chills, wheezing, productive cough with black sputum; eosinophilia; low O2 sat; IgE antibodies against Aspergillus; CXR shows infiltrates in upper lobes with branching, finger-like shadows.

Actinomyces (anaerobic); Nocardia (aerobic); gram-+, non-AF; slow-growing filamentous, branched rods; commensals; produce granules.

Dental procedure; painless mass on mandible draining pus and yellowish granules; branching, gram + rods; actinomyces israelli; must have pre-disposing factor: dental procedure or oromaxillofacial trauma; submandibular jaws; suppuration with draining abscess; grains or "sulfur granules" in tissues; rx = penicillin, + oral penicillin or amoxicillin

Chronic asthma; high dose steroids; productive cough, weight loss, night sweats; abscesses in lungs and brain; gram + filaments that are weakly acid fast; bilateral nodular opacities; GMS stain; opportunistic; ubiquitous saprophytes; local traumatic innoculation or inhalation; CMI-deficient at risk; cutaneous cellulitis/ mycetoma; pneumonia; disseminated -- deep abscesses and necrosis CNS; urease; rx = antibiotics TMP-SMX

What is the most common etiology for Pericarditis?

How are enteroviruses spread?

What is purulent spread? What are two examples that are spread this way?

What is are two chronic pathogens implicated in pericarditis?

How do cardiotropic viruses spread to the heart?

Do enteroviruses cause massive diarrhea?

Fatigue; progressive dyspnea 6 weeks after episode of massive diarrhea; bilateral pleural effusion; extensive pericardial effusion; acute inflammation confined to visceral and parietal pericardial layers; Latin America; small mammal reservoirs; transmission -- bite of the "kissing bug" or "assassin bug"; Triatoma, Rhodnius, or Panstrongylus; most people can clear this easily, but becomes chronic for some -- myocarditis is presenting symptom; incubation period of 4 days to 2 wks; localized infection -- initial lesion is a nodule with facial edema (chagoma or chancre); systemic infection via lymphatics or bloodstream; fever, lymphadenopathy, hepatosplenomegaly, myocarditis, megacolon, megaesophagus, denervation and loss of tone in GI tract; Ramana's sign; Trypomastigote stage in thick or thin blood smears; amastigote in BM aspirates/ muscle biopsies; PCR/serology; rx = benzidazole or nifurtimox

What are the two types of infective endocarditis?

What agents are responsible for the acute form of endocarditis?

What agents are responsible for the subacute form of endocarditis (native-valve)?

What agents are responsible for the subacute form of endocarditis (prosthetic valve)?

How do we differentiate between S. epidermidis and S. aureus?

How do we differentiate between staph and strep?

Streptococci are initially classified based on hemolysis. which two are beta-hemolytic? How do we differentiate between these two?

Streptococci are initially classified based on hemolysis. Which agent is gama-hemolytic?

Streptococci are initially classified based on hemolysis. Which two are alpha-hemolytic? How are these differentiated?

What type of strep are alpha-hemolytic, normal flora in oral cavity, and are responsible for dental carries?

What organisms are classified as viridans streptococci?

What type of strep is classified as alpha/gamma hemolytic, normal flora of large intestine, causes UTI, sepsis, and nosocomial infections. Can hydrolize esculin/grow in 6.5% NaCl and 40% bile salts

What organisms are classified as Enterococci or group D strep?

Which type of endocarditis, acute or subacute, has an abrupt onset of high-grade fevers, chills, and rapid heart rate? There is rapid destruction of the infected valve. Look for a history of antecedent procedures or illicit drugs; can be rapidly fatal.

Which type of endocarditis, acute or subacute, has symptoms that may be subtle and non-specific, including a low-grade fever, anorexia, weight loss, flu-like symtpoms, and anemia. Rarely causes metastatic infections. Symptoms may persist for weeks.

Identify the syndrome:
New/worsened regurgitant murmur
Cardiac complications
Arterial emboli
Splenomegaly
Neurological manifestations
Pulmonary symptoms
Subconjunctival hemorrhage
Janeway lesions
Osler's nodes