Last reviewed: August 2020
Last updated: April  2019



History and exam

Key diagnostic factors

  • presence of risk factors
  • prolonged fever
  • palpitations
  • syncope or presyncope
  • hepatosplenomegaly
  • enlarged lymph nodes
  • tachycardia
  • hypotension
  • cardiomegaly
  • dysphagia
  • regurgitation/aspiration
  • odynophagia
  • substernal discomfort
  • prolonged constipation
  • acute abdominal pain
  • abdominal distension
  • swelling around the site of inoculation
  • jaundice
  • abdominal rebound tenderness
  • clinical evidence of meningeal irritation
  • clinical signs of a cerebral mass lesion

Other diagnostic factors

  • irritability
  • anorexia or fatigue
  • vomiting or diarrhoea
  • headache
  • myalgia
  • reduced exercise tolerance
  • dizziness
  • thromboembolic phenomena (e.g., stroke, pulmonary embolism)
  • dyspnoea
  • cough
  • generalised oedema
  • pericarditis
  • epigastric pain and/or haematemesis
  • melaena or haematochezia
  • rash
  • seizures or tremors

Risk factors

  • living in endemic area
  • exposure to Triatoma species
  • low socio-economic status
  • consumption of contaminated food or drink
  • blood transfusion
  • organ transplantation
  • history of immunosuppression
  • climate change
  • deforestation
  • healthcare occupations
  • laboratory work occupations
  • travel to endemic areas
  • mother with Chagas disease

Diagnostic investigations

1st investigations to order

  • FBC
  • LFTs
  • serum electrolytes, urea nitrogen, and creatinine
  • microscopy: fresh blood
  • microscopy: concentration methods applied to fresh blood
  • microscopy: thick blood smear
  • enzyme-linked immunosorbent assay based on parasite lysate
  • immunofluorescent antibody test
  • indirect haemagglutination antibody test
  • polymerase chain reaction (PCR)
  • urinalysis
  • serum or urine beta-hCG
  • ECG with a 30-second lead II rhythm strip
  • chest x-ray
  • barium swallow
  • barium enema
More 1st investigations to order

Investigations to consider

  • culture (blood and cerebrospinal fluid)
  • xenodiagnosis
  • cerebrospinal fluid analysis
  • coagulation profile
  • ambulatory 24-hour ECG
  • exercise testing
  • echocardiography
  • oesophageal manometry
  • upper gastrointestinal endoscopy
  • cranial CT/MRI
  • cardiac MRI
  • nuclear medicine testing
  • cardiac catheterisation and coronary angiography
More investigations to consider

Emerging tests

  • radio-immunoprecipitation assay
  • immunofluorescent antibody test
  • western blot
More emerging tests

Treatment algorithm


Alberto Novaes Ramos Jr

Senior Lecturer

Department of Community Health

School of Medicine

Federal University of Ceará




ANR Jr is an author of a number of references cited in this topic. ANR Jr declares that he has no other competing interests.

Jorg Heukelbach


Department of Community Health

School of Medicine

Federal University of Ceará




JH declares that he has no competing interests.

Andréa Silvestre de Sousa

Adjunct Professor of Cardiology

Department of Internal Medicine

Federal University of Rio de Janeiro


Evandro Chagas National Institute of Infectious Diseases

Oswaldo Cruz Foundation

Rio de Janeiro



ASS declares that she has no competing interests.

Dr Alberto Novaes Ramos Jr, Dr Jorg Heukelbach, and Dr Andrea Silvestre de Sousa would like to gratefully acknowledge Dr Francisco Rogerlândio Martins-Melo, a previous contributor to this topic.

Peer reviewersVIEW ALL

Assistant Professor of Medicine

Division of Infectious Diseases

University of Vermont College of Medicine




CH declares that he has no competing interests.


London School of Hygiene and Tropical Medicine




RR declares that he has no competing interests.

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