QuestionSBA
QuestionChoice
This is incorrect because Cryptosporidium parvum typically presents with chronic watery, green diarrhoea in patients who are immunosuppressed (typically, those patients with HIV.)
53131
e
Cryptosporidium parvum
QuestionChoice
Leptospirosis is caused by Leptospira interrogans which can be transmitted by rats. Occupational exposure may occur through working in sewers. The key symptoms here are headache, fever, red eyes, deranged liver function tests, acute kidney injury, and reduced platelets. Note that patients with leptospirosis can also get diarrhoea, abdominal pain, and a rash. Liver and kidney failure may complicate its course.
53127
a
Leptospirosis
QuestionChoice
This is incorrect because lead poisoning would present with abdominal pain, mood changes, motor neuropathy and memory loss. Lead poisoning can also cause a microcytic anaemia and Burton's lines in the gums which appear blue. This is a good differential as lead poisoning can also present with headaches and may relate to this patient's occupation. However, the presence of conjunctivitis, his deranged blood results, acute presentation, and occupation should point towards leptospirosis.
53128
b
Lead poisoning
QuestionChoice
This is incorrect because Bartonella henselae causes a condition known as Cat Scratch disease. This presents with painful local lymphadenopathy and fever. There is no mention of a cat scratch in this case.
53130
d
Bartonella henselae
QuestionChoice
This is incorrect because asbestosis presents with gradually worsening shortness of breath. Occupational exposure may occur in those who work in construction or on boilers.
53129
c
Asbestosis
QuestionComment
I may not know the featurs of lepto but I sure do know you get it in the sewers
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subscriber
Supine Body
Concept
Chapter
# Summary
 
 
Leptospirosis is a zoonotic infection caused by a spirochete found in the urine of multiple animal species. It is typically misdiagnosed as malaria due to its similar presenting features. The disease is characterised by a biphasic illness, with an acute febrile phase followed by a phase marked by fever and potential complications such as liver failure and meningitis. Diagnosis is primarily achieved through serology, blood culture, and urine culture, while PCR of blood for *Leptospira* may also be used. Treatment is dependent on the severity of the disease and generally includes antibiotics such as doxycycline alongside supportive measures.
 
 
# Definition
 
 
Leptospirosis is a spirochete that represents a zoonotic infection found in the urine of multiple animal species. Typical animal hosts include **rodents** (main host), cattle, pigs, dogs, sheep and goats. Infection can be misdiagnosed as malaria.
 
 
# Epidemiology
 
 
 - Approximately 1 million cases per year 
 - Human infections occur from exposure to infected animals who excrete the organism in their urine, although it can also occur through cuts
 - Found widely in tropical regions 
 - Occupational exposure – increased risk in farmers, sewage and abattoir workers, as well as those from lower socioeconomic groups
 
 
# Signs and Symptoms
 
 
 - Spectrum of clinical features from self-limiting mild symptoms to life-threatening fatal disease
 - Classically a **biphasic illness**: first phase – acute febrile disease (2–9 days); second phase – fever and complications (eg. liver failure, meningitis etc.)
 - First phase presents with **abrupt fever**, **rigors**, **myalgia** and **headache** (75–100% of cases)
 - Classically conjunctival redness (can easily be missed)
 - Second phase can cause hepatosplenomegaly and skin rash as well as:
 - **Weil's disease** – presence of jaundice and renal failure (which can require dialysis)
 - **Life-threatening complications**– acute respiratory distress syndrome, pulmonary haemorrhage, myocarditis
 - **Aseptic meningitis**
 
 
 
 
# Investigations
 
 
 - **FBC** (may show thrombocytopenia), **U&E's** (low sodium & altered renal function), **raised CK**
 - **Serology** is the most frequently used test for diagnosis – can be delayed, becoming positive only on day 5–7 of the illness (**note:** if in an endemic area, it may be positive due to previous and not acute infection)<
 - **Blood culture** (gold standard) and **urine culture** can be used to confirm leptospirosis (during the first and second weeks of illness, respectively)
 - **PCR** of blood for *Leptospira* (if available)
 - **Chest X-ray**
 
 
# Management
 
 
 - Most cases are self-limiting and as such do not require treatment
 - There is a risk of **Jarisch–Herxheimer reaction** on administering antibiotics
 - For mild disease – doxycycline 7 days (if pregnant azithromycin)
 - For severe disease (eg. Weil's disease) – ceftriaxone 
 - ICU may be indicated for severe disease
 
 
### Prevention
 
 
Avoiding potential sources of infection (eg. stagnant water, rodent control and avoidance of food contamination)
 
 
# References
 
 
 1. [Costa F et al. Global Morbidity and Mortality of Leptospirosis: A systematic review. *PLoS Negl Trop Dis*.2015;9(9)](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4574773/)
 2. [Guerrier G, D'Ortenzio E. The Jarisch-Herxheimer reaction in leptospirosis: a systematic review. *PLoS One*.2013;8(3):]([https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3608636/)
 3. [Click here for further information about Leptospirosis](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8813018/pdf/clinmed-22-1-14.pdf)
 4. [Patient.info: Leptospirosis](https://patient.info/doctor/leptospirosis-weils-disease)
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Leptospirosis
Topic
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Infectious Diseases
10686
Leptospirosis, caused by Leptospira interrogans, presents with fever, headache, conjunctival suffusion, and can lead to liver and kidney dysfunction.
A 40-year-old man presents to A&E with a headache and itchy, red eyes for the past 8 days. He works as a water engineer and spends a lot of time in the sewers. He has no significant past medical history. On examination, his eyes are red and his liver edge is palpable. He has a low-grade fever of 37.7. Blood tests show a mildly raised AST and ALT, low platelets, and a high urea and creatinine.

Which of the following is the most likely diagnosis?
a