Spirochetes Flashcards
What lab findings are useful to help diagnose Borrelia burgdorferi? (3)
loosely coiled motile spirochete visualized by dark field microscopy or Giesma stain, but cultures of human samples are rarely positive; IgM or IgG antibodies in serum; PCR available.
What is the classic skin symptom of Lyme disease and how is it characterized?
erythema chronicum migricans. An expanding bulls eye red rash with central clearing.
What are the manifestations in stage two Lyme disease? (2)
neurologic and cardiac manifestations
What is the presentation of stage three Lyme disease? (1)
autoimmune migratory polyarthritis
What are the clinical features of 2nd degree syphilis? (4)
fever, lymphadenopath, skin rashes, condylomata lata
What symptoms are characteristic of end state syphilis? (4)
gummas, aortitis, neurosyphilis (tabes dorsalis), Argyll Robertson pupil
What are the clinical stages of Borrelia burgdorferi? (3)
lyme disease. Primary-erythema migrans (bulls eye lesion)a, flu-like symptoms. Secondary-months later, cardiovascular (heart block) and neurological (Bell’s palsy) syptoms. Tertiary-arthritis of large joints, especially knee joint.
What is the morphology of Leptospira interrogans?
spirochete
What are the clinical manifestations of Leptospira interrogans? (2)
well’s disease leptospirosis)-7-13 day incubation followed by fever, chills and intense headache which resolve. Second part of illness resembles aseptic meningitis with serious vasculitis jaundice, uremia.
How is Treponema pallidum transmitted? (2)
direct contact with lesion on mucous membranes. Also, mother to fetus (vertical) transmission.
How does Treponema pallidum gram stain?
negative
What is the morphology of Treponema pallidum?
spirochete (thin walled, flexible, motile spiral rods)
microbiology Vignettes: Middle-age man has acute monoarticular joint pain and bilateral Bells palsy. What diease and how?
lyme, ixodes tick
What are the symptoms of stage one Lyme disease? (2)
erythema chronicum migricans, flu-like symptoms
Identify the major toxicity factor associated with Treponema pallidum.
antigens induce antibodies that react with cardiolipin
Where in the US is Lyme disease common?
northeast (named after Lyme, Connecticut)
How is Leptospira Interrogans transmitted?
swimming in or drinking water contaminated by animal urine (rats, dogs, cows).
What lab findings are useful to help diagnose Treponema pallidum? (3)
cannot be grown on artificial media; Test is for anti-cardiollpin antibodies (RPL, VDRL tests); confirmation with other serological tests.
What is the morphology of Borrelia burgdorferi?
spirochete
What is the major reservoir for Borrelia burgdorferi?
white tailed deer
How is Borrelia burgdorferi transmitted?
deer-tick bite
What lab findings are useful to help diagnose Leptospira interrogans? (2)
tightly coiled spirochete only visible with dark field microscopy; only occasionally cultured from humans.
What are the clinical manifestations of Treponema pallidum? (4)
congenital syyphilis-impaired vision, hearing and notched teeth. Primary syphilis-hard, non tender primary lesion appears after a few weeks and is highly infectious. Secondary-a few month after primary lesion has gone, maculopapulary rash on palms and soles or moist papules on body; condylomata lata; can spontaneously heal. Tertiary-1/3 will progress to granulomas anywhere skin, bones; gummas in brain, ascending aortic aneurisms.
Treponemes are what type of organism?
spirochetes
What doe VDRL detect? What disease is it used for?
nonspecific antibody that reacts with beef cardiolipin. Used for diagnosis of syphilis.
How is Treponema visualized? Why?
dark-field microscopy, but only viewed after silver staining or with immunofluorescence. Very thin-walled structure.
