179 Leptospirosis Flashcards
Severe leptospirosis characterized by jaundice, renal dysfunction, hemorrhagic diathesis
Weils syndrome
With or without jaundice, this is increasingly recognized as important presentation of severe disease
Pulmonary hemorrhage
Microscopic description of leptospires
Coiled thin motile organisms hooked ends and two peripheral flagella with Polar extrusions form the cytoplasmic membrane responsible for motility
Important reservoir of leptospirosis
Rodents esp rats
True or false. Leptospires can persist in the urogenital tract for years
True
Mode of transmission of leptospires
Direct contact with urine, blood or tissues from infected animal or exposure to contaminated environment
Important vehicle in the transmission of leptospirosis
Water
True or false. Leptospires cause no or only mild disease in humans; severe fatal cases are only 1%
True
How does leptospires evade compliment mediated killing
Binding to factor H
Incubation period of leptospirosis
Usually 1-2 weeks but ranges from 1 to 30 days
What are the phases of leptospirosis? And how can the organism be cultured in these phases
Leptospiremic phase (fever of 3-10 days duration) : cultured from blood and detected by PCR Immune phase (resolution of symptoms): leptospires are cultured from urine
Physical findings that are pathognomonic of leptospirosis
Fever Conjunctiva suffusion Pharyngeal injection Muscle tenderness Lymphadenopathy Rash Meningismus Hepatomegaly Splenomegaly
Muscle pain in leptospirosis common affects what?
Calves
Back
Abdomen
True or false. Leptospirosis can be cultured form CSF in the immune phase
False. Leptospira can be cultured from CSF in the early phase
Natural course of mild leptospirosis usually resolves spontaneously within how many days?
7 to 10 days
What is the case fatality of leptospirosis?
1-50%
What factors are associated with higher mortality
Age more than 40
Altered mental status
Acute renal failure
Arrhythmias
Triad that encompasses Weil’s syndrome
Hemorrhage
Jaundice
Acute kidney injury
Bleeding complications in leptospirosis
Lungs
GIT
Urogenital
Skin: bleeding from venipuncture sites
True or false. Jaundice in leptospirosis is associated with fulminant hepatic necrosis
False
Loss of what in the urine is uniquely associated with leptospira nephropathy
Loss of magnesium
Typical electrolyte imbalance in leptospirosis
Hypokalemia
Hyponatremia
Recognized sequelae of leptospirosis
Auto immune associated uveitis
Characteristic of early leptospirosis
Nonoliguric Hypokalemia renal insufficiency
Most common radiographic findings in leptospirosis and what lobes are commonly affected
Patchy bilateral alveolar pattern that corresponds to scattered alveolar hemorrhage in the lower lobes
Definite diagnosis of leptospirosis
Isolation of organism on PCR
True or false: antibodies in leptospirosis are detected as early as the first week of infection
False. Antibodies generally do not reach detectable levels until second week of illness
Dual infection in leptospirosis has been reported. It is advisable to contact serologic test for what diseases when leptospirosis is suspected?
Rickettsiae
Dengue virus
Hantavirus
Antibiotics susceptible to leptospirosis
Beta lactans
Cephalosporins
Aminoglycosides
Macrolides
Leptospirosis is not susceptible to what antibiotics
Vancomycin
Rifampicin
Metronidazole
Chloramphenicol
Treatment of leptospirosis. Which is not given during pregnancy?
Mild
Moderate/severe
Chemoprophylaxis
Mild: doxycycline, amoxicillin, ampicillin
Moderate/Severe: penicillin, Ceftriaxone, cefotaxime, doxycycline IV
Chemoprophylaxis: doxycycline, Azithromycin
Not given during pregnancy: doxycycline
Drug of choice for leptospirosis when Rickettsial disease are co endemic?
Doxycycline
Azithromycin
True or false. Glucocorticoids and desmopressin are adjunct therapy for pulmonary hemorrhage in leptospirosis
False. Evidence is contradictory
Treatment of leptospirosis. Mild
Doxycycline 100 mg BID
Amoxicillin 500 mg TID
Ampicillin 500 mg TID
Treatment of leptospirosis. Moderate
Penicillin 1. 5 million units q6hrs
Ceftriaxone 2 grams IV per day
Cefotaxime 1 gram IV q6hrs
Doxycycline 200 mg IV LD then 100 mg IV q12h
Chemoprophylaxis leptospirosis. Pregnant vs non pregnant
Non pregnant: doxycycline 200 mg PO weekly or Azithromycin 250 mg PO once or twice a week
Pregnant: Azithromycin 250 mg PO once or twice a week
How long does acute phase in leptospirosis lasts?
5-7 days
How long does immune phase lasts
4-30 days
When does immune phase commence
Appearance of IgM antibodies
