Chagas disease

Background

• Also known as American Trypanosomiasis
• Endemic in rural parts of Cental and South America
  • Rare cases found in Southern United States
• Caused by the parasite trypanosoma cruzi
  • Vector: Reduviid (kissing bug)
  • The parasite is transmitted in the feces of the host vector
    • When the vector bites, it also defecates and the parasites enter the blood stream through the bite wound

Transmission

Triatoma infestans,a common vector for T. cruzi

• Disease of poverty
  • Spread by the Triatominae bug (also known as the kissing bug)
    • The Triatomina bug thrives in housing that is old, has thatched roofs and dwellings where the roof does not abut the wall.
• Other methods of transmission
  • Vertical (mother to child)
  • Transfusion/organ donation

Clinical Features

Acute phase

• Romañas sign
  • swelling of the eye thought to be secondary to rubbing the feces into the eye
• Chagoma
  • Localized swelling at the area of parasite entry
• Non-specific signs and symptoms
  • Fever, fatigue, myalgia, headache, anorexia, vomiting, diarrhea
• Serious complications
  • Myocarditis, arrhythmia, encephalitis

Chronic phase

• Between 20-40% of patients will develop chronic complications
• Cardiac complications
  • Dilated cardiomyopathy (CHF)
  • Dysrhythmias
• GI complications
  • Megaesophagus
  • Megacolon
  • Achalasia
  • Volvulus
  • Hepatosplenomegaly (secondary to HF)
• Neuro symptoms
  • Neuritis

Evaluation

• ECG
• LFTs
• Blood smear
  • Can visualize parasites
  • PCR, ELISA, immunofluorescence

Management

• Benznidazole or Nifurtimox
• Symptomatic treatment

External Links

• CDC: American Trypanosomiasis (also known as Chagas Disease)

See Also

• Parasitic Diseases
• Travel Medicine
• Cardiomyopathy