Chagas disease laboratory findings

Jump to navigation Jump to search

Chagas disease Microchapters


Patient Information


Historical Perspective




Differentiating Chagas disease from other Diseases

Epidemiology and Demographics

Risk Factors


Natural History, Complications and Prognosis


Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings



Echocardiography and Ultrasound

CT scan


Other Imaging Findings

Other Diagnostic Studies


Medical Therapy


Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Chagas disease laboratory findings On the Web

Most recent articles

cited articles

Review articles

CME Programs

Powerpoint slides


American Roentgen Ray Society Images of Chagas disease laboratory findings

All Images
Echo & Ultrasound
CT Images

Ongoing Trials at Clinical

US National Guidelines Clearinghouse

NICE Guidance

FDA on Chagas disease laboratory findings

CDC on Chagas disease laboratory findings

Chagas disease laboratory findings in the news

Blogs on Chagas disease laboratory findings

Directions to Hospitals Treating Chagas disease

Risk calculators and risk factors for Chagas disease laboratory findings

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Yazan Daaboul, M.D.


Acute Chagas disease is often diagnosed by peripheral blood smear following the visual detection of T. cruzi parasite. Serology is often helpful for chronic cases only, where assay positivity of both "whole parasite lysate" and "recombinant antigen" is usually required for the diagnosis. Although PCR is sensitive in acute cases (e.g. exposure following organ transplantation), its sensitivity and specificity are variable in the chronic state and highly depend on the pre-test probability.

Laboratory Findings

Blood smear

  • Acute Chagas disease is often diagnosed by visual detection of the T. cruzi parasite on peripheral blood smear.
  • Peripheral blood smears are usually stained with Giemsa stain for adequate visualization of the parasite.


  • Serology is not usually helpful in acute Chagas disease.
  • Detection of anti-trypanosomal IgG antibodies is helpful to detect chronic Chagas disease infections.[1][2]
  • A single assay for chronic T. cruzi infection is neither sensitive nor specific, and positive results from both "whole parasite lysate" and "recombinant antigens" are required to make the diagnosis of chronic Chagas disease.[1][2]
  • Detection of antibodies among infants may be difficult due to the presence of maternal antibodies early following birth. Accordingly, serologic testing for infants is only recommended at least 9 months after birth.[3]


  • In acute disease, PCR is very sensitive and is widely used today to detect accidental exposure among organ transplant recipients following organ transplantation
  • In chronic disease, PCR sensitivity and specificity depend on the pre-test probability of Chagas disease.[4]
  • Serial PCR measurements are often necessary to confirm the diagnosis of Chagas disease.[4]
  • Quantitative PCR is helpful to monitor for Chagas reactivation, and increasing parasitic load on PCR is considered a sensitive surrogate of reactivation.[5]


  1. 1.0 1.1 Rassi A, Rassi A, Marcondes de Rezende J (2012). "American trypanosomiasis (Chagas disease)". Infect Dis Clin North Am. 26 (2): 275–91. doi:10.1016/j.idc.2012.03.002. PMID 22632639.
  2. 2.0 2.1 Tarleton RL, Reithinger R, Urbina JA, Kitron U, Gürtler RE (2007). "The challenges of Chagas Disease-- grim outlook or glimmer of hope". PLoS Med. 4 (12): e332. doi:10.1371/journal.pmed.0040332. PMC 2222930. PMID 18162039.
  3. Bern C, Martin DL, Gilman RH (2011). "Acute and congenital Chagas disease". Adv Parasitol. 75: 19–47. doi:10.1016/B978-0-12-385863-4.00002-2. PMID 21820550.
  4. 4.0 4.1 Schijman AG, Bisio M, Orellana L, Sued M, Duffy T, Mejia Jaramillo AM; et al. (2011). "International study to evaluate PCR methods for detection of Trypanosoma cruzi DNA in blood samples from Chagas disease patients". PLoS Negl Trop Dis. 5 (1): e931. doi:10.1371/journal.pntd.0000931. PMC 3019106. PMID 21264349.
  5. Duffy T, Bisio M, Altcheh J, Burgos JM, Diez M, Levin MJ; et al. (2009). "Accurate real-time PCR strategy for monitoring bloodstream parasitic loads in chagas disease patients". PLoS Negl Trop Dis. 3 (4): e419. doi:10.1371/journal.pntd.0000419. PMC 2667272. PMID 19381287.
  6. 6.0 6.1 6.2 6.3 "Public Health Image Library (PHIL)".