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Category:Leptospiraceae (view source)

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''Leptospiraceae'' is a family of [[Spirochaetes species - Overview|''spirochaetes'']]. It includes the genus ''Leptospira''.

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~~===''Leptospira''===~~

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*Motile, helical bacteria found in aquatic environments

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==Overview==

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*Require liquid media for culture

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''Leptospira'' is a motile, helical bacteria found in aquatic environments. It causes leptospirosis in all animals, which can range from mild urogenital tract infections to systemic diseases. The organisms persist in the kidney tubules or genital tracts of carrier animals and are shed in urine. Transmission occurs via direct contact. Maintenance hosts may transmit the infection to incidental hosts, which are less susceptible to infection, but develop serious disease. ''Leptospira'' may cause severe systemic disease, resulting in [[Septicaemia and Enteritis, Bacterial|enteritis]].

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*Cause leptospirosis in all animals, which can range from mild urogenital tract infections to systemic diseases

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*Organisms persist in kidney tubules or genital ~~tract~~ of carrier animals and are shed in urine

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*Transmission via direct contact

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*Serovars are fairly host-specific, causing mild disease in the maintenance host, with shedding in the urine

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*Maintenance hosts may transmit the infection to incidental hosts, which are less susceptible to infection, but develop serious disease

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* May cause severe systemic disease, resulting in [[Septicaemia and Enteritis, Bacterial|enteritis]]

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*Pathogenesis and pathogenicity

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**Depends on virulence of the serovar and susceptibility of the host

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**Leptospires invade tissues through moist skin or via mucous membranes, aided by their motility

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**Leptospires may invade via receptor-mediated endocytosis

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**They disseminate through the body via the blood stream

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**Antibodies clear organisms from the blood stream after about 10 days of infection

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**Organisms may persist in the renal tubules, uterus, eye or meninges

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**Evade phagocytosis possibly via macrophage apoptosis

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**Damage red blood cell membranes and endothelial and liver cells, leading to haemolytic anaemia, jaundice, [[Pigmentation and Calcification - Pathology#Haemoglobin|haemoglobin pigmentation]], haemoglobinuria and haemorrhage in acute leptospirosis

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*Diagnosis

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==Pathogenesis==

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**Clinical signs and history of exposure

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The pathogenesis of ''Leptospira'' depends on virulence of the bacteria and susceptibility of the host. Leptospires invade tissues through moist skin or via mucous membranes, aided by their motility. They may invade via receptor-mediated endocytosis and then pass through the body via the blood stream. Antibodies clear the organisms from the blood stream after about 10 days of infection.

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**Dark-field microscopy of urine may detect organisms

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**Isolation from blood or urine by culture or animal inoculation

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The organisms may persist in the renal tubules, uterus, eye or meninges. They evade phagocytosis possibly via macrophage apoptosis and damage red blood cell membranes and endothelial and liver cells, leading to haemolytic anaemia, jaundice, [[Pigmentation and Calcification - Pathology#Haemoglobin|haemoglobin pigmentation]], haemoglobinuria and haemorrhage in acute leptospirosis.

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**Identificaiton or certain serovars using DNA probes and serology

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**FLuorescent antibody technique for identification in tissues

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==Diagnosis==

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**Silver impregnation

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''Leptospira'' can be diagnosed by clinical signs and history of exposure. Dark-field microscopy of urine may detect organisms as may isolation from blood or urine by culture or animal inoculation.

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**Molecular techniques such as PCR

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The fluorescent antibody technique can be used for identification in tissues. Silver impregnation, molecular techniques such as PCR and Serology using microscopic agglutination test or ELISA can also be used.

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**Serology using microscopic agglutination test or ELISA

[[Category:Spirochaetes]]

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[[Category:To_Do_-~~_Bacteria~~]]

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[[Category:To_Do_-_AimeeHicks]]

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