Table 1.
Clinical phenotype of patients 1–6.
| Clinical phenotype | P1 | P2 | P3 | P4 | P5 | P6 |
|---|---|---|---|---|---|---|
| Ethnic origin | Turkish | Moroccan | German | German | ||
| Gender | Female | Male | Male | Female | Male | Male |
| Age/initial presentation at disease onset | 9 months/infections | 3 months/failure to thrive | 12 months/leukoplakia | 4 years/diarrhea | 9 years/pancytopenia and infections | 19 years/thrombocytopenia |
| Age at last follow-up | 7 years 4 months | 19 months | 7 years 8 months | 7 years 8 months | 21 years | 19 years |
| Treatment | MFD HSCT | None | Matched unrelated donor HSCT | Careful watching | Oxymetholone | None |
| Outcome | Alive (HSCT + 4 years 2 months) | Deceased (CMV) | Alive (HSCT 2 years 6 months) | Alive | Deceased (pneumonia) | Alive |
| RTEL1 mutations | c.1368G>T; p.Trp456Cys hom | c.1274T>C; p.Ile425Thr hom | c.2652 + 5G>C; p.Pro884_Gln885ins53X13 het and c.3730delTG; p.Cys1244ProfsX17 het | c.2387delT; p.Val796AlafsX4 het | ||
| Major dyskeratosis congenita (DC) featuresa | ||||||
| Bone marrow failure | + | + | + | − | + | + |
| Oral leukoplakia | + | + | + | − | + | − |
| Abnormal skin pigmentation | − | − | − | − | − | − |
| Nail dystrophy | − | − | − | − | + | − |
| Telomere length <first percentile | + | + | + | + | + | + |
| Other DC-related features | ||||||
| Ataxia/cerebellar hypoplasia on MRI | +/+ | +/+ | +/+ | −/n.i. | −/n.i. | −/n.i. |
| IUGR | + | − | − | − | + | − |
| Short stature | + | + | + | − | − | − |
| Microcephaly | + | + | + | − | + | − |
| Developmental delay | + | + | + | − | − | − |
| Esophageal stricture or GI ulcerations | + | − | + | − | + | − |
| Lung fibrosis/liver cirrhosis | +/− | −/− | −/− | −/− | −/+ | −/− |
| Chronic diarrhea | + | + | + | + | + | − |
| T+B−NK− immune phenotype | + | + | + | + | + | − |
| MMC-induced chromosomal breakage | + fibroblasts | n.i. | + fibroblasts | n.i. | − blood | n.i. |
| − blood | − blood | |||||
| Systemic infections | Viral and bacterial | Bacterial | None | Viral and bacterial | none | |
aAs defined in Dokal (1).
hom, homozygous; het, heterozygous; +, present; −, absent; n.i., not investigated; MFD HSCT, matched family donor hematopoietic stem cell transplantation; IUGR, intrauterine growth retardation; MMC, mitomycin C.