83 terms

Bacterial systemic infection table w/ NGR

This set addresses every piece of information from the excel table provided by NGR
Identify Characteristics of Rickettsial Diseases/Rickettsiosis
Gram(-) coccobacilli; take gram staining weakly; obligate intracellular pathogens; zoonotic pathogens
Rocky Mountain Spotted Fever is caused by what pathogen?
Rickettsia rickettsii (Spotted fever group)
Identify the Reservoir for Rickettsia rickettsii
Wild Rodents, domestic animals (dogs)
True or False? The vector & transmission of RMSF is a tick & tick bite, respectively
Describe the virulence factors & pathogenesis of Rickettsia rickettsii
Infect vascular endothelial cells → (1) induced endocytosis (2) lysis of phagosome membrane - phospholipase A (3) replication in host cell cytoplasm (4) lysis of host cell (Filopodium focal lysis)→ vascular damage (hemorrhage, edema), LPS - weak endotoxin activity, vasculitis and thrombosis
Describe the clinical features of RMSF
Flu-like symptoms, petechial-hemorrhagic rash (first on extremities → spread to entire body); various organs failures. Fever + Rash + Previous tick bite
Describe the process for diagnosis of Rickettsial Diseases/Rickettsiosis
Clinical presentation + Serologic tests (indirect immuno-fluorescence assay, immuno-staining)
True or False? The treatment for Rickettsial Diseases/Rickettsiosis is Amoxicillin
False. The treatment for Rickettsial Diseases/Rickettsiosis is Doxycycline
True or False? Rickettsia akari is in the Spotted Fever group & causes Scrub Typhus
False. Rickettsia akari is in the Spotted Fever group, but causes Rickettsialpox
Identify the reservoir for Rickettsia akari
Wild Rodents
Identify the vector & mode of transmission for Rickettsialpox
Vector: Mouse Mite

Transmission: Mite Bite
Describe the Clinical Features of Rickettsialpox
Eschar at bite site; Dissemination → flu-like symptoms + fever + generalized rash (randomly distributed)
True or False? Rickettsia prowazekii is in the Typhus group & causes Epidemic typhus & Brill-Zinsser disease (Recrudescent typhus)
True or False? Concerning Rickettsia prowazekii infection:
*Reservoir = humans, squirrels
*Vector = Human body louse
*Transmission = Louse bite
True. True. True.
Describe the clinical presentation of Epidemic Typhus and/or Brill-Zinsser Disease
Flu-like symptoms; maculopapular rash (first on trunk → spread to extremities); myocarditis, CNS dysfunction; Recrudescent typhus = (10-40 yrs later) endogenous secondary infection by R. prowazekii persisting in reticuloendothelial cells
True or False? Rickettsi typhi is in the Typhus group & causes Epidemic Typhus
False. Rickettsia typhi is in the Typhus group but caused Endemic Typhus
True or False? Concerning Endemic Typhus & it's causative pathogen:
*Reservoir = Humans, squirrels
*Vector = Mite Larva
*Transmission = Louse bite
*Reservoir = Rats
*Vector = Flea
*Transmission = Flea bite
How do R. prowazekii bugs get out of the host cell? How is this different than R. rickettsii & R. tsutsugamushi?
*R. prowazekii = lysis of cell

*R. rickettsii = filopodium focal lysis

*R.tsutsugamushi = budding
Describe the clinical presentation of Endemic Typhoid
Flu-like symptoms, gradual onset, rash on trunk
True or False? Orientia tsutsugamushi is the only bug in the Scrub Typhus group & causes Scrub Typhus
Identify the reservoir for Scrub Typhus
What is the vector & manner of transmission of Orienta tsutsugamushi?
Vector = Mite larva (chigger)

Transmission = Chigger bite
True or False? Clinical presentation of Scrub Typhus will include necrotizing eschar at bite site & a maculopapular rash that first appears on the trunk but spreads to extremities
True. Necrotizing eschar at bite site; flu-like symptoms; maculopapular rash (first on trunk → spread to extremities)
Ehrlichia chaffeensis causes what?
Human Monocytic Ehrlichiosis (HME)
True or False? Anaplasma phagocytophilia is the causative agent for Human Monocytic Ehrlichiosis (HME)
False. Anaplasma phagocytophilia causes Human Granulocytic Ehrlichiosis (HEG)
Identify the vectors for HME
HME vectors = Lone star tick
Identify the reservoir for Ehrlichia chaffeensis
Deer, dogs
True or False? HME is transmitted by bite from the Black Legged Tick & HEG is transmitted by a bite from the Lone Star Tick

HME: bite from the Lone Star Tick

HEG: bite from the Black Legged Tick
Describe the pathogenic process of both the Ehrlichiosis diseases
Infect leukocytes → (1) phagocytosis (2) Inhibition of phagosome-lysosome fusion + multiplication in cytoplasmic vacuoles - Morula (3) Host cell + phagosome lyses
What is the difference between the infective process of HME vs HEG?
*HME: Primarily infect mononuclear leukocytes (monocytes, macrophages)

*HEG: Primarily infects granulocytes (neutrophils)
True or False? Concerning diagnosis of the Ehrlichiosis diseases, it includes Clinical presentation + Microscopy: Giemsa (Morulae) + Serologic tests: IFA, PCR
This is exactly what is needed to diagnose the Ehrlichiosis dieseases
True or False? Just like the Typhus diseases & RMSF diseases, Gentamicin or Streptomycin is the appropriate course of treatment
False. RMSF, Typhus & the Ehrlichiosis diseases should be treated w/ Doxycycline.
True or False? Bartonella, Brucella, Yersinia Pestis & Burgdorferi are all Gram(-) spirochetes
False. Y.Pestis, F.tularensis, Brucella & B. quintana are all G(-) Coccobacilli
Describe the characteristics of Yersinia pestis
Gram(-) rod, lactose (-), oxidase (-), nonmotile, bipolar staining; facultative intracellular pathogen; zoonotic pathogen
Identify the reservoirs of Y.pestis & what each kind means for the differences in infection.
Y.pestis reservoirs:
Wild rodents (Sylvanic cycle); Urban rats (Urban cycle)
True or False? The reservoir for plague is the flea & the vector & mode of transmission is the rat
False. Y.pestis:
*Reservoir: Wild rodents (Sylvanic cycle); Urban rats (Urban cycle)

*Vector: Flea

*Transmission: Flea bite; direct contact w/ respiratory droplets (only pneumonic plague)
Describe the Virulence factors & pathogenesis of Y.pestis
Virulence plasmids; Changes in genes expression in response to environmental changes (1) Changes in flea behavior: agglutination in flea's GI tract; (2) Survival in human body: Capsule (F1 protein), plasminogen activator: prevents opsonization, important for dissemination (3) Damage: Type III secretion system: Yop proteins (cytotoxic effect); endotoxin (septic shock); intracellular grow in reticuloendothelial cells
Describe clinical features of the 3 kinds of plague due to Y. pestis infection
Bubonic plague: flu-like symptoms; Multiplication in regional lymph node => suppurative lymphadenitis = "Bubo"

Pneumonic plague: from bacteremia or inhalation: flu-like symptoms + cough, bloody sputum, dyspnea and cyanosis (rapid death due to septic shock)

Septicemic plague (Black death): necrosis of
peripheral blood vessels + disseminated intravascular coagulation
Bipolar staining is often times a sign of a positive gram stain for Y.pestis. True or False?
Describe how to diagnose plague & what tests would need to be done
Serologic tests: direct immunofluorescence test (rapid, presence of F1); microscopy: gram stain or Giemsa - bipolar staining, culture: highly infectious
True or False? Concerning treatment of Plague, the only thing that need be done is administration of Streptomycin or Gentamicin.
False. Streptomycin or Gentamycin should be given but also the PT should be put under quarantine
Describe the characteristics of Francisella tularensis. Does it have a capsule?
Gram(-) coccobacilli, requires cysteine, facultative intracellular pathogen; zoonotic pathogen, thin lipid capsule
F.tularensis causes Trench fever. True or False?
False. F.tularensis is the causative agent of Tularemia.

Trench Fever is caused by Bartonella quintana.
Concerning F.tularensis:
*Reservoir = wild animals (rabbits, squirrels, deer, etc)

*Vector = Hard shell tick, deer fly

*Transmission = tick/fly bite, direct contact, inhalation/ingestion of contaminated food or water
F. tularensis infects RE organs, multiplies in T-cells. True or False.
False. Infects reticuloendothelial organs: multiplication in macrophages, hepatocytes and endothelial cells => necrosis and granuloma production in areas of multiplication; Survival: inhibition of phagosome-lysosome fusion; antiphagocytic lipid capsule
How does the causative pathogen for tularemia survive inside the macrophage.
F.tularensis inhibits the phagosome-lysosome fusion process & it has a antiphagocytic lipid capsule
What form of Tularemia is most common?
Ulceroglandular occurs at a 75% rate
Describe the different types of Tularemia
Ulceroglandular form (75%): painful ulcerating lesion at site of infection
Oculoglandular form (1%): purulent conjunctivitis + lymphadenopathy
Pneumonic, Gastrointestinal & Septicemic forms (10-15%, more severe)
True or False. Concerning diagnosis of Tularemia: Serologic tests (PCR, gram stain unsuccessful, it requires cysteine-glucose blood agar)
This is the process of diagnosing Tularemia
As is the agents used to treat plague, tularemia treatment is with Streptomycin or Gentamicin.
True or False? Brucella spp is a G(-) coccobacilli that is an obligate intracellular, zoonotic pathogen
False. Brucella spp:
Gram(-) coccobacilli facultative intracellular pathogens, zoonotic pathogens
True or False? Concerning Brucella spp:
*Reservoir = humans
*Vector = Human body louse
*Transmission = louse bite
False. Brucella spp.:
*Reservoir = domestic livestock
*Vector = none
*Transmission = direct contact/inhalation/ingestion of unpasteurized dairy products
Similar to the Tularemia pathogen, Brucella spp multiplies in macrophages in the reticuloendothelial system
Describe the infective process of Brucella spp. How does it do this?
Brucella spp.:
Multiply in macrophages in reticuloendothelial system => granulomas => septicemia.

It Inhibits phagosome-lysosome fusion; and has endotoxin
True or False? With Brucellosis, there will be few physical findings unless there is enlargement of reticuloendothelial organs. What else might be clinically relevant?
True. Flu-like symptoms; night sweats (undulant fever); Chronic illness: body aches, headache, anorexia, depression... few physical findings unless enlargement of reticuloendothelial organs.
True or False? In Brucellosis diagnosis there will need to be serologic tests & possibly a culture done
Identify the treatment concerning Brucellosis infection
Brucellosis: Doxycycline + rifampin (for 6 weeks)
True or False? Bartonella quintana is a G(-) coccobacilli bug that is a facultative intracellular, zoonotic pathogen
False. It is a G(-) coccobacilli zoonotic pathogen, yes, but it is not a factultative intracellular pathogen. That describes Brucella spp.
What diseases does Bartonella quintana cause?
B. quintana causes:
Trench fever, bacillary angiomatosis, subacute endocarditis
All Borrellia & Leptospiras are spirochetes
Describe the characteristics of Borrelia burgdorferi, Borrelia recurrentis & other Borrelia spp.'s
Spiral morphology, large, gram(-); motile (endoflagella); zoonotic pathogens, hard to isolate in culture, complex nutritional needs, slow growth
Borrelia burgdorferi causes what?
Lyme Disease
True or False? Concerning Borrelia burgdorferi infection:
*Reservoir = humans
*Vector = human body louse
*Transmission = louse bite
False. Lyme Disease:
*Reservoir = wild rodents
*Vector = Black Legged Tick
*Transmission = Tick bite
Describe the virulence factors & pathogenesis of B. burgdorferi, the causative agent of Lyme Disease
Virulence Factors/Pathogenesis:
Antigenic variation - escape immune clearance; autoimmune activities of anti-Osp

Osp (Outer Surface Protein); LPS; autoimmune response
Describe clinical features of stages 1-3 concerning Lyme Disease
Stage1: (localized infect.): erythema migrans (bull's eye appearance) + flu-like symptoms

Stage2: (disseminated infect.): cardiac and neurologic (nerve palsies) abnormalities

Stage3 (persistent infection): fluctuating arthritis.
To diagnose Lyme Disease, first perform a Western Blot & then do an ELISA or IFA test. Also, definitely do a culture to confirm diagnosis
False. To diagnose Lyme Disease, assess clinical presentation, then perform ELISA or IFA THEN a Western Blot. A culture is not recommended.
Identify the appropriate course of treatment for Lyme Disease
Lyme Disease Treatment:
*Doxycycline or Amoxicillin
True or False? Borrellis recurrentis has a spiral morphology, it is motile & demonstrates slow growth. It is G(-) but is not seen on a gram strain. It is a zoonotic pathogen & has tight terminal hooks
False. That description is for Leptospira interrogans.

Borrelia recurrentis: Spiral morphology, large, gram(-); motile (endoflagella); zoonotic pathogens, hard to isolate in culture, complex nutritional needs, slow growth
True or False? B. recurrentis is responsible for Endemic relapsing fever
False. B. recurrentis is responsible for Epidemic Relapsing Fever.
The Reservoir, vector & transmission for B. recurrentis is humans, human body louse & louse bite, respectively. True or False?
True or False? B. recurrentis demonstrates antigenic variation & Osp
False. B. recurrentis does have antigenic variation, which aids in escaping immune clearance. It doesn't have Osp, but secretes endotoxin.
Describe Virulence factors & pathogenesis of B. recurrentis & other Borrelia spp.'s
Virulence factors/pathogenesis of B. recurrentis:

Antigenic variation - escape immune clearance; autoimmune activities of anti-Osp

Endotoxin (febrile illness); Recurrent episodes of fever + septicemia separated by afebrile periods; new set of surface antigens at each relapse
Identify the clinical features of Epidemic or Endemic Relapsing Fever
Epidemic Relapsing Fever:

High fever, headache, muscle pain, weakness. 2-4 days between relapses; 2-3 relapse cycles
Describe the diagnostic aspects of Epidemic or Endemic Relapsing Fever
Epidemic Relapsing Fever diagnostic process:

Microscopy (during febrile period) Giemsa or Wright staining; Serologic tests unhelpful (because of antigenic variation)
True or False? To treat Epidemic or Endemic Relapsing Fever, administer Penicillin or Doxycycline
False. Doxycycline or Erythromicin
True or False? Numerous Borrellia infections will cause Epidemic Relapsing Fever, but only B. recurrentis causes Endemic Relapsing Fever.

Borrellia recurrentis: Epidemic Relapsing Fever

Other Borrelia spp.: Endemic Relapsing Fever
What is the difference between reservoirs, vectors & transmission of Epidemic versus Endemic Relapsing Fever?
Epidemic Relapsing Fever:
*Reservoir = Humans
*Vector = Human body louse
*Transmission = Louse bite

Endemic Relapsing Fever:
*Reservoir = Rodents & other small animals
*Vector = Tick
*Transmission = Tick bite
Describe the characteristics of the Leptospira interrogans bug
Leptospira interrogans:
Spiral morphology; motile; slow growth; gram(-) but not seen on gram stain; zoonotic pathogen, tight terminal hooks
True or False? Concerning Leptospirosis:
*Reservoir = Dogs, livestock, rats, wild animals (colonize renal tubules)
*Vector = in urine of infected animals
*Transmission = Direct contact w/ urine, blood or tissues of infected animals. Contact w/ contaminated water.
True or False? L.interrogans multiplies inside macrophages
Describe the pathogenesis of L. interrogans
L. interrogans multiplies in blood & tissue, it damages the endothelium of small blood vessels. Supposedly it has no virulence factors, but it could be argued that the morphology of the hooks are in and of themselves virulence factors.
Describe the Septicemic & Immune phase of Leptospirosis
both febrile:
Septicemic phase: flu-like symptoms

Immune phase: anicteric form (possible meningitis), icteric form or Weil's disease (jaundice, renal failure, subconjunctival hemorrhage)
True or False? Penicillin or Doxycycline are the appropriate therapeutic agents for Leptospirosis