Leptospirosis

Question 1

How is Leptospirosis spread?

Answer 1

Leptospirosis is caused by the spirochaete Leptospira interrogans (serogroup L. icterohaemorrhagiae), classically being spread by contact with infected rat urine.

Question 2

Who is usually affected by leptospirosis?

Answer 2

• sewage workers, farmers, vets or people who work in an abattoir
• leptospirosis is far more common in the tropics so should be considered in the returning traveller

Question 3

What is Weil’s disease?

Answer 3

Another name for leptospirosis but more severe disease e.g. hepatorenal failure

Question 4

What are the clinical features of leptospirosis?

Answer 4

The early phase is due to bacteraemia and lasts around a week

• may be mild or subclinical
• fever
• flu-like symptoms
• subconjunctival suffusion (redness)/haemorrhage
  second immune phase may lead to more severe disease (Weil’s disease)
• acute kidney injury (seen in 50% of patients)
• hepatitis: jaundice, hepatomegaly
• aseptic meningitis

Question 5

What investigations may be used to diagnose Leptospirosis?

Answer 5

Serology: antibodies to Leptospira develop after about 7 days
PCR
Culture -

• But growth may take several weeks so limits usefulness in diagnosis
• Blood and CSF samples are generally positive for the first 10 days
• Urine cultures become positive during the second week of illness

Question 6

What is the treatment (abx) for leptospirosis?

Answer 6

high-dose benzylpenicillin or doxycycline