RESUMEN
BACKGROUND: Donor cell leukemia (DCL) is a relatively rare but well documented complication of hematopoietic stem cell transplantation. So far, publications described only DCL arising de novo in the recipient. OBSERVATION: In this study, we describe a case of chronic lymphocytic leukemia (B-CLL) developing in a volunteer unrelated donor from the Czech National Marrow Donors Registry (CNMDR) several years after donation. From archival DNA sample, we have retrospectively found that subclinical CLL clone was already present at the time of donation but early death of recipient prevented eventual development of DCL. This case documents well the long period between detection of B-CLL clone and full development of clinical-laboratory symptomatology. The medical and ethical questions posed by an isolated case of detection of hematological malignancy present either only in the donor or only in the recipient are discussed. CONCLUSION: The case demonstrates the increasing risk of development of various forms of DCL and thus highlights the need for long-term monitoring of stem cell donor, not only in terms of health of donor but also in terms of potential risks for the recipient.
Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Linfocítica Crónica de Células B/etiología , Donante no Emparentado , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Masculino , Persona de Mediana EdadRESUMEN
We determined the feasibility of universal fetal marker detection in maternal circulation. Using real-time PCR, we compared the levels of fetal (SRY and hypermethylated RASSF1A) and total (GLO gene and total RASSF1A) extracellular DNA and fractions of extracellular fetal DNA (SRY/GLO vs. hypermethylated RASSF1A/total RASSF1A) in maternal circulation. Sensitivity and specificity reached 100% as the fetal-specific hypermethylated RASSF1A sequence was detected in all 151 examined plasma samples derived from 70 normal pregnancies with a singleton male (n=51) or female (n=19) fetus sampled throughout gestation and absent in non-pregnant individuals (n=29). A strong positive correlation was observed between fetal-derived hypermethylated RASSF1A and SRY (ρ=0.66, P<0.001), total RASSF1A and GLO (ρ=0.65,P<0.001), SRY/GLO vs. hypermethylated RASSF1A/total RASSF1A ratio (ρ=0.62, P<0.001) in maternal plasma. The results indicate that a universal fetal marker could be useful not only for the confirmation of the presence of fetal cell-free DNA in maternal plasma but could enable quantification of cell-free fetal DNA in pregnancy associated disorders, independently of the sex of the fetus.
Asunto(s)
ADN/sangre , Feto , Embarazo/sangre , Diagnóstico Prenatal/métodos , Proteínas Supresoras de Tumor/sangre , Oxidorreductasas de Alcohol/sangre , Oxidorreductasas de Alcohol/genética , Metilación de ADN/genética , Femenino , Humanos , Masculino , Embarazo/genética , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Proteína de la Región Y Determinante del Sexo/sangre , Proteína de la Región Y Determinante del Sexo/genética , Proteínas Supresoras de Tumor/genéticaRESUMEN
Fetal extracellular DNA is mainly derived from apoptotic bodies of trophoblast. Recent studies have shown size differences between fetal and maternal extracellular DNA. We have examined the quantification of fetal (SRY gene) and total (GLO gene) extracellular DNA in maternal plasma in different fractions (100-300, 300-500, 500-700, 700-900, and >900 bp) after size fractionation by agarose gel electrophoresis. DNA was extracted from maternal plasma samples from 11 pregnant women carrying male foetuses at the 16th week of gestation. Fetal circulatory DNA was mainly detected in the 100-300 bp fraction with the median concentration being 14.4 GE/ml. A lower median amount of 4.9 GE/ml was also found in the 300-500 bp fraction. Circulatory DNA extracted from the 100-300 bp fraction contained 4.2 times enriched fetal DNA when compared with unseparated DNA sample. Fetal DNA within the 300-500 bp fraction was 2.5 times enriched. Circulatory fetal DNA is predominantly present in a fraction with molecular size <500 bp, which can be used for the detection of paternally inherited alleles. However, the usage of size-separated DNA is not suitable for routine clinical applications because of risk of contamination.