Rat bite fever Flashcards
Streptobacillus moniliformis vs Spirillum minus
Gram stain
pleomorphic fusiform GNB vs GN coiled with 2-6 turns
treatment of both
penicliin G; tetracycline
Oligoarticular or migratory polyarthritis
ARF
RA
IE
Septic arthritis
Brucella
Lyme
Gonococcus
Rat bite fever
Streptobacillus moniliformis vs Spirillum minus
diagnosis
direct visualisation; culture in trypticase soy broth with 10-20% rabbit, horse or sheep serum or defibrinated blood - 2-10 days- puffballs in broth; nonhemolytic cooton like fried egg colonies in solid agar; PCR
SPS inhibits it
25% false positive syphilis serology
vs
direct visaulisation - DGM - silver flagella staining- terminal plytrichous flagella; xenodiagnosis; no culture or PCR
50% false positive syphilis serology
Streptobacillus moniliformis vs Spirillum minus
geographic distribution
North america and Europe vs Asia (In japan, called sodoku)
Streptobacillus moniliformis vs Spirillum minus
cf
<10 days IP - abrupt onset of fever, chills, myalgia, arthralgia - after 2-4 days of fever, nonpruritic maculopapular, petechial or pustular rash over palm, sole , extrimities; 50% asymmetrical large polyarthirits (knee, elbow writst, shoulder, ankle, hip).. fever subsides in 3-5 days- others in 2 weeks.. relapsing fever rarely; can involve all organs
fever, chills, malaise
rash- blotchy violaceous or red brown macular rash over extremitis, face, scalp, trunk
ulcerates and indurates
regional ln
recurring- last 3-4 days recurs at 3-9 days
can involve all organs
Streptobacillus moniliformis vs Spirillum minus
mode of transmission
bite by rodents (rats- wild and lab, guinea pigs, mice, squirrels and carnivores such as dogs, cats, ferrets which eat these rodents - 50-100% colonisation-10% infection rate) and ingestion (turkey or milk or water contaminted with rat faeces - Haverhill fever- epidemics, high rates of pharyngitis and severity of vomiting) vs bite (25% colonisation)
