Leptospira Flashcards
what does leptospira look like
long spiral
gram negative
hooks at one or both ends
respriation of leptospira
strict aerobe
uses long chain fatty acids as carbon soruce
growth of leptospira
growth media requires supplementation
5-10% serum
albumin + B1
B12
purines
5-flurouracil
what is leptospira sensitive to
heat
light
disinfectants
what are 2 taxonomic systmeis based on
1 – virulence and antigenic differneces
2 – genetic differneces
what are the non pathogenic lepto from virulence based taxonomic grouping
L biflexa (all serovars)
what are the pathogenic lepto from virulence based taxonomic grouping
L interrogans (all serovars)
what is natural reservoir of lepto
lumen of nephritic tubules
can lepto survive following excretion in urine
yes in fresh water, soil, mud
no in saltwater, low pH, low humidity, low temp
what two virulence factors are mutant confirmed
catalase
motility
what does lepto cause
premature birth
abortion
infertility
jaundice
agalactia
hemoglobinuria
what does lepto cause in dogs
acute hemorrhagic or chronic icteric and uremic syndromes
liver and kidneys affected
general signs of lepto infection
fever
inappetance
malaise (general feelings of sickness/uncomfyness)
lab changes with lepto infection
hemoglobinuria
increased BUN
what are the 3 forms of lepto in dogs
hemorrhagic
icteric
uremic
what can lepto infection result in in dogs
kidney failure
severe liver disease
has been fatal following shock
what can hematogenous spread of lepto to kidneys cause
carrier state in lumen of nephritic tubules (especially in rodents)
where may lepto persist in large animals
uterus
can infect fetus – abortion, weak offspring
transmission of lepto
natural habitat – proximal convoluted tubules of kidney in many reservoir hosts
infection by exposure to contaminated urine
transplacental transmission – cow, horse, pig
through milk
through semen (venereal)
what serovar is adapted to Norway rats
icterohaemorrhagiae
what immunity is important
humoral
are antibodies serovar specific
possibly
control of lepto
know local serovars – vaccines
prevent exposure
diagnosis of lepto
darkfield microscopy
serology – 4 fold titer change between acute and convalescent samples
what may be the best test for lepto
microscope agglutination test
isolation or passage in hamsters
5-fluoroacil can be added to contaminated specimens
growth appears as diffuse zone then ring (dinger’s ring) near top of tube (strict aerobe)
do antibiotics eliminate spirochetes from kidney
some antibiotic may not eliminate spirochetes from kidey
may not eliminate carrier state
treatment of lepto
ampicillin, penicillin G, ceftriaxone, streptomycin, teracycline, doxycycline
what can penicillin cause and wht may you need to add to prevent it
Jarisch-Herxheimer (endotoxic shock) reaction
may need to add steroids
is lepto zoonotic
yes
people swimming in contaminated water at risk
lepto in people
weil’s disease – similar to rpesentaion in dogs
how many people get lepto each year, how many deaths
more than 1 million people contract a tropical disease known as leptospirosis each year, resulting in nearly 59,000 deaths
what may cause prevalence of lepto to rise
as climate change affects global temperatures and urbanization accelerates, the prevalence of leptospirosis is likely to rise
