Table 5.
Summary of clinical Chagas disease publications, which included genotyping to discrete typing unit level: years 2005–2014.
| Study region, country, year | Sample size and clinical classification† | Type of clinical sample | Clinical classification | Patient DTU‡ | Genotyping methodology | Ref. |
|---|---|---|---|---|---|---|
| Endemic and non-endemic regions Argentina (2012) | 95 IND 69 CCM (blood) 8 CCM (heart tissue)§ |
Venous blood Tissue: explanted heart, endomyocardial |
ND | IND: 1 TcII/VI, 34 TcII/V/VI (36%), 54 TcV (57%), 1 TcVI, 5 TcV or TcV + II/VI CCM (blood): 50 (72%) TcII/V/VI, 16 (23%) TcV, 1 TcII/VI, 2 TcV or TcV + TcII/VI CCM (tissue): 3 (38%) TcI, 2 (25%) TcII/VI, 2 (25%) TcII/V/VI, 1 TcVI |
Nuclear SL-IR 24Sα rDNA A10 (all) [135] |
[188] |
| Cochabamba, Bolivia (2006) | 18 MC | Colon tissue | ND | MC: 2 TcII, 16 TcV (89%) |
kDNA Southern blots [137,327] |
[192] |
| Santa Cruz, Bolivia (2010) | 54 IND 29 CCM 5 CCM-MC 15 MC 29 MC-UK cardiac status |
Venous blood | ECG Colon x-ray Barium enema |
IND: 1 TcII, 9 (17%) TcI/V, 44 (81%) TcV CCM: 2 TcII, 6 (21%) TcI/V, 20 (69%) TcV, 1 TcVI CCM-MC: 1 TcII/V, 4 TcV MC: 3 TcI/V, 1 TcII/V, 11 (73%) TcV MC-UK: 4 TcI, 3 TcII, 4 TcI/V, 1 TcI/II/V, 17 TcV (59%) |
kDNA Southern blots [327] |
[189] |
| Manaus, Brazil (2014) | 11 IND 2 CCM |
Xenodiagnoses feces | ND | IND: 11 (100%) TcI CCM: 2 (100%) TcI |
Nuclear SL-IR [41] kDNA COII [54] |
[182] |
| Goiás, Bahia, Minas Gerais, Brazil (2009) | 27 IND 17 CCM |
Parasite cultures from hemoculturing | ECG Chest x-ray Echocardiogram |
IND: 26 TcII (96%), 1 TcIII CCM: 16 TcII (94%), 1 TcV/VI |
Nuclear SL-IR 24Sα rDNA [135] Microsatellites (9 loci) [102] kDNA COII [54] |
[190] |
| Minas Gerais, Brazil (2006) | 8 IND 19 CCM 10 ME 2 MC 18 CCM-ME 3 CCM-MC 10 CCM-MC-ME |
Parasite cultures from hemoculturing | ECG Barium swallow Barium enema |
IND: 8 Trypanosoma cruzi II CCM: 19 T. cruzi II ME: 10 T. cruzi II MC: 2 T. cruzi II CCM-ME: 18 T. cruzi II CCM-MC: 3 T. cruzi II CCM-MC-ME: 10 T. cruzi II |
Nuclear 24Sα rDNA [41] |
[191] |
| Goiás, Bahia, Minas Gerais, Brazil (2005) | 11 CCM 16 ME 1 MC |
Tissues: heart, esophagus, colon |
ND | CCM: 11 T. cruzi II ME: 16 T. cruzi II MC: 1 T. cruzi II |
Nuclear 24Sα rDNA [193] |
[193] |
| IV, V and Metropolitan regions, Chile (2009)¶ | 17 IND 13 CCM |
Venous blood (XD results excluded)‡ |
ECG Chest x-ray Echocardiogram |
IND: 1 TcII, 1 TcI + II, 2 TcII + hybrid, 13 (76%) TcI + II + hybrid CCM: 1 TcI, 1 TcII, 1 TcII + hybrid, 10 (77%) TcI + II + hybrid |
kDNA Southern blots [327] |
[197] |
| IV, V and Metropolitan regions, Chile (2010)¶ | 33 IND 28 CCM |
Venous blood (XD results excluded) ‡ |
ECG Chest x-ray Echocardiogram |
IND: 26 (79%) TcI, 5 TcII, 1 TcIII, 1 TcV\VI CCM: 16 (57%) TcI, 6 TcII, 6 TcIII |
Nuclear Microsatellites (3 loci) |
[198] |
| IV region, Chile (2013)¶ | 28 IND 24 CCM |
Venous blood‡ | ND | IND: 24 (86%) TcI, 3 TcII, 1 TcIII CCM: 17 (71%) TcI, 6 TcII, 1 TcIII |
Nuclear Microsatellites (3 loci) [133] |
[199] |
| Santander, Colombia (2010) | 28 IND 31 CCM |
Venous blood | ECG Holter echocardiogram |
IND: 21 (75%) TcI, 5 TcII, 2 TcI + II CCM: 27 (87%) TcI, 4 TcII |
Nuclear SL-IR 24Sα rDNA [41] kDNA COII [54] |
[183] |
| Santander, Colombia (2011) | 10 CCM | Cardiac tissue (autopsy) | Pathology only | CCM: 8 (80%) TcI, 2 TcII |
Nuclear SL-IR [41] |
[184] |
| Endemic regions, Guatemala and Mexico (2005) | Guatemala: 3 Acute 1 IND Mexico: 1 Acute 4 IND 7 CCM |
Parasite cultures from hemoculturing | ECG Chest x-ray |
Acute: 4 (100%) TcI IND: 5 (100%) TcI CCM: 7 (100%) TcI |
Nuclear SL-IR [41] |
[185] |
| Endemic regions, Mexico (2013) | 3 Acute 11 IND 6 CCM |
Parasite cultures from hemoculturing | ND | Acute: 3 (100%) TcI IND: 11 (100%) TcI CCM: 6 (100%) TcI |
Nuclear SL-IR [41] |
[186] |
| Endemic regions, Panama (2006) | 5 acute 7 IND 11 CCM |
Xenodiagnoses and hemoculturing | ND | Acute: 5 (100%) TcI IND: 7 (100%) TcI CCM: 11 (100%) TcI |
Nuclear SL-IR [41] |
[187] |
†Patients classified as indeterminate if no barium studies are performed, patients with megacolon by barium studies but no ECG are classified as MC-UK cardiac status.
‡XD omitted as specimens could not be matched to patients.
§Same heart explants reported in [104].
¶Participants in follow-up after allopurinol clinical trial. Unspecified degree of overlap in patient populations in these three studies.
CCM: Chagas cardiomyopathy; DTU: Discrete typing unit; IND: Indeterminate; kDNA: Kinetoplast DNA; ME: Megaesophagus; MC: Megacolon; ND: Not described; SL-IR: Spliced-leader intergenic region; UK: Unknown status; XD: Xenodiagnostic data.