Flashcards in Infectious Disease 4 Deck (80):
Two main types of vector borne diseases?
Intracellular and Extracellular
2 types of Intracellular VBD?
Rickettsia and Erlichiosis
2 Types of Rickettsia?
Epidemic typhus and Rocky Mountain Spotted Fever
What causes Rocky Mountain spotted fever?
What causes Epidemic typhus?
What are three extracullar VBD?
1) Lyme disease
2) Relapsing fever
What causes Lyme Disease?
What causes Plague?
What can be found at the bite location in Rickettsia?
Crusted lesion (eschar)
How does one diagnose Rickettsia?
Immunostaining or anti-rickettsial serology
Where do Rickettsia mainly multiply??
Small vessel endothelia
What are severe manifestations in Rickettsia due to?
Vascular leakage secondary to endothelial cell damage
What are the severe manifestations of Rickettsia?
Rash, fever, and CNS manifestations
In Rickettsia what does small vessel vasculitis cause?
Microthrombi, focal ischemia, and hemorrhage
What does typhus group Rickettsia do to endothelial cells?
How does Spotted Fever group Rickettsia spread?
Spreads from cell to cell
Risk of Rickettsia spread?
Hypovolemic shock and peripheral edema
What type of exotoxins/endotoxins does Rickettsia have?
While lacking exotoxins/endotoxins what does Rickettsia possess?
LPS which is non-toxic
What causes much of the tissue damage in Rickettsia?
Cytotoxic T-cell immune response
What do you use for treatment of Rickettsia?
What do Rubella, Rubeola, and Erlichiosis almost never do?
Shock or DIC
Which strain of Rickettsia is known as Epidemic Typhus?
How is R. Prowazekii transmitted?
What does rash look like in Prowazekii?
Moves away from center (centrifugal)
In Prowazekii, what happens after rash development?
CNS involvement with apathy, or coma
What are the severe clinically findings of severe Prowazekii?
Gangrene of fingers, nose, earlobes, scrotum, penis, vulva
What types of ticks cause R. rickettsi?
Dog tick and wood tick
What is incubation time for R. rickettsi
What does the rash look like for R. Ricksttsi?
Hemorrhagic rash that extends over entire body including palms and soles, possibly eschar
Where does the R.Rickettsi rash begin?
Periphery to trunk
Major cause of death for Spotted Fever group?
Noncardiogenic pulmonary edema
Is the Spotted fever group exudative or transudative?
What is scrub typhus?
Orienta transmitted by mites that resembles typhus.
What is the rash like in scrub typhus?
Transitory or absent
How does Erlichiosis differ from RMSF?
No eschar, rash is rare
What does Erlichiosis infect?
Neutrophils or monocytes
Why is the rash not as prominent in Erlichiosis?
It doesn't affect endothelial cells as much
What is defining characteristic for Erlichiosis?
Cytoplasmic inclusions called morulae. Masses of bacteria
Ticks of the white tailed deer are involved in what VBD?
How does Borrelia (Lyme Disease) avoid host antibodies?
Shifts antigenic markers
What parts of the body does LD affect?
CNS, joints, heart
LD is referred ti as what type of inflammatory disorder?
How do you treat LD?
How do you prevent LD?
What is the primary stage of LD?
Skin rash appear and shows target lesion
What is secondary and tertiary phases of LD?
Arthritis, polyneuropathy, encephalitis, and cardiac arrythmias
What is the bullseye mark in LD known as?
Erythema chronicum migrans
How long does it take LD to reach secondary part of the disease?
What causes the secondary disease in LD?
Dissemination of spirochetes
How long until LD tertiary disease appears?
What allows for relapsing fever or Borrelia recurrentis?
Ability of organism to express new surface antigens
How is plague spread?
What type of cycle does Plague follow?
Where does plague proliferate?
What does injection of yersinia outer proteins do?
Inhibits secretion of inflammatory cytokines and inactivates molecules that regulate actin polymerization
Symptoms of epidemic typhus?
Fever, chills, cough, rash, severe muscle pain, delerium, and sensitivity to light
Shape of tularemia?
Gram neg coccobacillus pleomorphic
Where does tularemia go, intra or extra?
How do you get tularemia?
Tularemia fatalities asscoiated with what?
3 types of tularemia worth knowing?
How do you get pasturella multocida?
Animal bites, primarily cats
How does pasturella present?
Rapidly (24 hrs) with cellulitis, abscesses, and sepsis
How do you treat pasturella?
Disease associated with kittens?
Cat scratch disease (Bartonella Henselae)
What does Bartonella cause?
How do you get Ornithosis?
Dust borne contaminated ecreta from birds
Lethal presentation of Ornithosis shows up as?
Focal necrosis in liver and spleen
Mononuclear changes in kidney's heart, and brain
Toxoplasmosis found where intra or extra?
Who is toxoplasmosis most dangerous to?
Infants in utero
Where during pregnancy is the infant most at risk from toxo?
What does Leptospirosis resemble?
What is Weil's disease?
Severe leptospirosis with jaundice, bleeding, and renal failure
Besides Weil's disease what is another presentation of Leptospirosis?
Lymphocytic atypical meningitis
What does Listeriosis look like?
Gram + rod
How do you get Listeriosis?
Contact with infected abortion, during vaginal childbirth
Forms of Listeriosis?
What does Brucellosis look like?
Gram - coccobacilli