Table 1.
Main characteristics of included studies.
| Author, year, country | # of patients per group and extension of Tx | Age at Tx | Follow-up | Exclusion criteria |
|---|---|---|---|---|
| Gudmundsdottir et al., 2017, Sweden (17) | Case: 11 (>90% thymic removal) Control: 11 HS |
<6m | 18y after Tx | Clinical signs or symptoms suggestive of a syndromic congenital cardiac malformation, including trisomy 21, 22q11.2 deletion syndrome, or CHARGE syndrome |
| Silva et al., 2017a, Portugal (6) | Case: 7 (total Tx, LT) Control: 20 HS |
Early infancy | Median of 24y of age | Not mentioned |
| Silva et al., 2017b, Portugal (28) | Case1: 8 (total Tx, VLT) Case2: 14 (total Tx, LT) Control: 20 HS |
Median of 21m (Case1) and 8m (Case2) | Median of 23y of age (Case1) and 25y (Case2) | Not mentioned |
| Van den Broek et al., 2017, Netherlands (7) | Case1: 10-27 (total Tx, 1-5y) Case2: 26 (total Tx, >9y) Control1: 10-31 (HS 1-5y) Control2: 11 (HS > 10y) |
<1m | 1-5y after Tx, 9-29y after Tx (mean 16y) | Clinical signs of infection at time of blood draw and the presence of a syndrome or genetic disorder (e.g., 22q11 deletion, trisomy 21) |
| Gudmundsdottir et al., 2016, Sweden (9) | Case: 11 (>90% thymic removal) Control: 11 HS |
<6m | 18m and 18y after Tx | Syndromic cardiac malformation or a known genetic disorder |
| Van den Broek et al., 2016, Netherlands (10) | Case1: 17 (total Tx, <5y) Case2: 26 (total Tx, >10y) Control1: 19 (HS 1-5y) Control2: 11 (HS > 10y) |
<1m | Median of 2.12y of age (Case1) and 15.89y of age (Case2) | Clinical signs of infection at time of inclusion and the presence of a syndrome or genetic disorder (e.g., 22q11 deletion, trisomy 21) |
| Zlamy et al., 2016, Germany (29) | Case1: 23 (total Tx, <24m) Case2: 12 (total Tx, >24m) Control: 26 HS |
Median of 0.2y (Case1) and 5.1y (Case2) | Median of 17.9y of age (Case1) and 17.4y of age (Case2) | Same as Prelog (23) |
| Elder et al., 2015, USA (18) | Case: 10 (total Tx) Control: 8 (CHD, no Tx) |
<1y | > 18y of age | Patients with known or suspected DiGeorge syndrome, current pregnancy, serious infection requiring hospitalization or medication within the prior 3 months, or NYHA class III-IV |
| Schadenberg et al., 2014, Netherlands (25) | Case: 26: (total Tx) Control: 17 (CHD, no Tx and HS) |
<1m | Median of 11.4m of age | Patients with a known syndrome or genetic disorder (eg 22q11 deletion and trisomy 21) |
| Kurobe et al., 2013, Japan (19) | Case: 17 (total Tx) Control: 15 (partial Tx and no Tx) |
<3m | 6, 12, 18, 24, 30 and 36m after Tx | Patients with trisomy 21 and chromosome 22q11.2 deletion syndrome |
| Sauce et al., 2012, France (27) | Case: 25 (total Tx) Control: 20 HS |
<2w | Median of 22y of age | Residual cyanosis, transplantation or immunosuppressive therapy, cortisone therapy or hematologic disorders, medication with drugs known to influence blood production in the bone marrow or the immune system |
| Cao et al., 2011, China (20) | Case1: 20 (small partial Tx) Case2: 15 (sub-total Tx) Control1: 12 (CHD, no Tx) Control2: 25 HS |
– | 0, 1, 3, 6 and 12m after Tx (TREC level) 1m after Tx (other tests) |
History of recent infections, received blood products or immune inhibitors or DiGeorge syndrome |
| Van Gent et al., 2011, Netherlands (16) | Case: 39 (total Tx) Control1: 102 (HS 0-18y) Control2: 52 (HS 21-39y) |
<1.5y | 2m – 31y after Tx | Clinical signs of infection at time of blood draw and the presence of a syndrome or genetic disorder (e.g., 22q11 deletion) |
| Eysteinsdottir et al., 2009, Iceland (30) | Case: 16 (total or partial Tx) Control: 16 HS |
Mean of 2.2m | Mean of 14.1y of age | Not mentioned |
| Prelog et al., 2009, Austria (23) | Case1: 58 (total Tx, <12y) Case2: 43 (total Tx, >12y) Control: 81 HS |
Mean of 2.6y (Case1) and 3.2y (Case2) | Mean of 11.1y of age | Residual cyanosis, transplantation or immunosuppressive therapy, cortisone therapy or hematologic disorders, medication with drugs known to influence blood production in the bone marrow or the immune system, allergic disorders, syndromes (eg. trisomy 21 and 22q11 deletion, excluded by genetic screening), vaccination or infections in the last 2-6 weeks prior to taking blood sample |
| Sauce et al., 2009, France (24) | Case: 25 (total Tx) Control: 90 HS |
<2w | Median of 22y of age | Blood transfusion, residual cyanosis, genetic disorder, transplantation, hematologic disorders, immunosuppressive or cortisone therapy, or other medications known to influence the bone marrow or the immune system |
| Mancebo et al., 2008, Spain (21) | Case: 23 (Tx
a
) Control: 105 HS |
<1m | 0, 6, 12, 18, 24 and 36m after Tx | Patients with DiGeorge syndrome (by investigating the 22q11.2 chromosomal deletion) |
| Torfadottir et al., 2006, Iceland (15) | Case: 8 (total or partial Tx) Control: 8 HS |
Mean of 2.5m | Mean of 12.1y of age | Not mentioned |
| Halnon et al., 2005, USA (26) | Case1: 18 (partial Tx) Case2: 11 (total Tx) Control: 26 (CHD, no Tx) |
<7y | Mean of 4.7y of age (Case1) and 8.4y of age (Case2) | 22q11 chromosomal deletion (by fluorescence in situ hybridization) or recent infections |
| Eysteinsdottir et al., 2004, Iceland (31) | Case: 19 (total or partial Tx) Control: 19 HS |
Mean of 2.6m | Mean of 10.1y of age | Not mentioned |
| Wells et al., 1998, USA (22) | Case: 25 (Tx
a
) Control: 10 HS |
<1m | 3 and 12m of age | Patients with DiGeorge syndrome or asplenia |
| Ramos et al., 1996, Brazil (32) | Case1: 13 (total Tx, <1y) Case2: 10 (total Tx, >1y) Control: 23 (CHD, no Tx) |
Mean of 7.9m (Case1) and 2.9y (Case2) | Mean of 5.5y of age (Case1) and 8.3y of age (Case2) | Not mentioned |
| Brearley et al., 1987, UK (3) | Case: 18 (Tx
a
) Control1: 18 (CHD, no Tx) Control2: 18 HS |
<3m | 9m – 3y after Tx, | Not mentioned |
CHD, congenital heart disease; HS, health subjects; LT, low TRECs; M, months; NYHA, New York Heart Association; Tx, thymectomy; VLT, very low TRECs; W, weeks; Y, years.
a
No description of Tx extension.