Borrelia and Leptospira genus Flashcards
General Features of Borrelia Burgdorfrei and its habitat
Gram (-) but too thin to visualize with gram staining
Spirochete
Habitat in wild deer (obligatory host of adult tick), Wild rodents (thick larvae)
Biochemical properties of Borrelia Burgdorfrei
Microaerophilic (hard to cultivate)
Pathogenesis of Borrelia Burgdorfrei
Transmitted by a tick bite (Ixodes ricinus tick- hard-shelled tick)
Frequent in the Northeast of USA
Clinical Features (Lyme disease) First stage of Borrelia Burgdorfrei
3 days to 10 days, fades and disappear
Erythema Chronicum Migrans- ECM (A.K.A “bull’s eye rash”)
Flu-like symptoms (fever, headache, fatigue, malaise)
Second Stage of Lyme disease
Few days to weeks, bacteria spread hematogenously in untreated patient
Headache, fever, arthralgia (pain in joint), myositis (muscle inflammation), skin lesions
Heart block caused by myocarditis
Facial nerve palsy (similar to bilateral Bell’s palsy)
Other neurological problems (meningitis, radiculoneuritis)
Third stage of Lyme disease
Months to years, late persistent- chronic stage
Polyarthritis of large joints (e.g. knee)
Meningitis, encephalopathy and other neurological disorders (depression etc.)
Cardiomyopathies (and others like- arrhythmias, heart inflammations etc.)
If the CNS is involved it is known as neuroborreliosis, usually already chronic
Diagnosis of Borrelia Burgdorfrei
Giemsa stain or Wright stain- from muco-cutanous lesion with eosin, methylene blue
and azure B, used to differentiate between bacteria and human cells (blood cells)
Serology (most important)-
ELISA and IF
Confirmation by Western Blot
Antibody detection from liquor can also be done
PCR- from muco-cutanous lesion
Treatmen tof Borrelia Burgdorfrei
Amoxicillin (Penicillin) or Doxycycline (Tetracycline)- for early stage
Ceftriaxone (and also Penicillin, Doxycycline, Amoxicillin)- for late stage
Prevention of Borrelia Burgdorfrei
Keep good hygiene and remove ticks from body (within 12-24 hours)
General Features of Leptospira interrogans
Gram – (but too thin to visualize)
Spirochete (thinnest)- question mark shaped (“hooked” ends)
Habitat- zoonosis (24 serovarients: rodents, dogs etc.)-
animals are asymptomatic carriers, bacteria colonize the renal tubules
Pathogenesis of Leptospira interrogans
Transmitted by animal’s urine, higher risk of spreading in water (rice fields, ponds)
Portal of entry- skin injury, mucous membranes, conjunctiva
Affects multiple different organs by hematogenous spread
Clinical Features of Leptospira interrogans
Leptospirosis (usually asymptomatic)
1st Stage- bi-phasic disease (begins after 1-2 weeks of incubation)
First phase- acute or septic phase (3-7 days)
Rapid onset of fever, muscle pain, headache, nausea (flu-like symptoms)
Conjunctival suffusion- red but no purulent exudate
Might heal spontaneously in 1 week or persist to second phase
Second phase
Rapid onset of fever
Meningitis and CNS involvement (hallmark of the second phase)
2nd Stage Weil’s disease (the severe form, caused by Leptospira icterohaemorrhagiae)
Renal failure- immune complex glomerulonephritis
Liver dysfunction- hepatitis and jaundice
Aseptic meningitis (serous, non-purulent), uveitis, exanthema
Pulmonary hemorrhage (most life-threatening symptom)
Diagnosis of Leptospira interrogans
Cultivation of blood, CSF (first 10 days) or urine (2-3 weeks since it does not reach high concentration in humans)
Korthof medium or Fletcher’s medium- aerobic, temperature of 28-30C
Serology- PCR and Microscopic Agglutination-lysis Test (MAT) for antibody detection 24 serotypes with each different animal
Treatment of Leptospira interrogans
Penicillin (I.V., start early, for 5 days), Doxycycline
Ceftriaxone, Erythromycin, Fluoroquinolone
Prevention of Leptospira interrogans
Vaccine- only for animals (inactive bacteria)
