1/248. Variable pathogenicity of exon 43del (FAA) in four Fanconi anaemia patients within a consanguineous family. Four Fanconi anaemia group A (FAA) patients within two related consanguineous families are presented: the propositus (male, 13 years, transplanted at age 10), and his three cousins (one male, 8 years, and two female newborns). Assignment of the patients to FAA was based on the functional complementation analysis by somatic cell hybridization and confirmed by mutation screening showing a homozygous deletion of exon 43 (4267-4404del) in the FAA gene to be present in all four patients. The newborn patients had been diagnosed prenatally by dna analysis. In spite of identical molecular pathology and close familial relationship the clinical phenotypes of the four patients were not concordant. Discordant symptoms included birthweight, pigmentation abnormalities, skeletal, renal and genital abnormalities, whereas microcephaly and possibly the haematological course were concordant. Differences in environmental conditions and/or genetic make-up along with chance effects during development may explain discordant phenotypes despite identical molecular pathology in these patients. However, our results do not rule out the possibility that the exon 43del mutation may have prognostic value for the haematological course of the disease. ( info) |
| bone marrow transplantation (BMT) is currently the treatment of choice for patients with fanconi anemia (FA) if a suitable donor is available. Four children with FA underwent allogeneic BMT from HLA-identical siblings during the period from 1995 to 1996. Pretransplant conditioning was cyclophosphamide (Cy) (20 mg/kg) Thoracoabdominal irradiation (TAI) (500 cGy) /- Antithymocyte globulin (ATG) (2 mg/kg/day x 3). Cyclosporin A (CsA) was used as GvHD prophylaxis. The time of neutrophil (ANC>500) and platelet (>50,000) recovery were at 11-14 and 17-25 days, respectively. One patient with a pretransplant history of multiple transfusions experienced graft rejection and died at day 29 with infection and bleeding. Although three patients sustained engraftment one developed donor originated acute lymphoblastic leukemia (ALL) 18 months after BMT and died with CNS hemorrhage and infection at 25 months following 7 months of chemotherapy. None of the patients developed grade 3-4 acute GvHD. Cytotoxicity included grade II mucositis in all and severe gastroenteritis in one patient. During a follow-up period of 10 months and 2 years, two patients are well with normal blood count, recovering immune function and have a Karnofsky score of 90%. ( info) |
| monosomy 7 is frequently found in the bone marrow of patients with fanconi anemia (FA), marrow myelodysplasia, or acute myelogenous leukemia and is associated with poor prognosis. In our laboratory, cytogenetic analysis of bone marrow from an FA patient found 2 of 30 cells with monosomy 7, but the results of fluorescence in situ hybridization (FISH) indicated that 83 of 207 cells (40%) had monosomy 7. FISH was then used to analyze two earlier samples from the index case, neither of which had monosomy 7 as determined by standard cytogenetics. The FISH analysis determined that the first sample, taken 19 months earlier, had 8 of 200 cells (4%) with monosomy 7 and the second sample. taken 7 months later, contained 43 of 200 cells (21.5%) with monosomy 7. These results indicate a slow evolution toward monosomy 7 in the patient's bone marrow. Standard metaphase chromosome analysis represents only spontaneously dividing cells, leading us to hypothesize that FISH was detecting monosomy 7 in nondividing cells and that it might be useful in the early detection of abnormal clones. To test this hypothesis, FISH was performed on 13 bone marrow samples from nine patients with FA who did not exhibit monosomy 7 by cytogenetic analysis. monosomy 7 was detected in 3.44% of nuclei in FA patients and in 3% of nuclei in normal controls. To date, none of these nine FA patients have developed monosomy 7 or leukemia. They are being monitored by standard cytogenetics and by FISH to determine whether monosomy 7 develops and whether it can be detected by FISH prior to its detection by standard cytogenetics. As standard practice, we have adopted FISH analysis for monosomy 7 in all patients with FA. ( info) |
| Seckel syndrome is a rare autosomal recessive disorder. The classical presentation includes pre- and postnatal growth deficiency, mental retardation, and characteristic facial appearance. There have been several reports of associated hematological abnormalities and chromosomal breakage, findings suggestive of fanconi anemia (FA). We tested for these findings in two Arabic patients with this syndrome. We compared the growth profile of lymphoblastoid cells from our patients and their parents with the FA group A cell line HSC72 in the presence and absence of mitomycin C (MMC). By Western analysis, we also determined the expression of FAA and FAC, two FA disease gene products that together account for approximately 80% of FA. Unlike HSC72 cells, cells from the patients were resistant to MMC, and both FAA and FAC proteins were expressed at similar levels in all cell lines. There is an increasing recognition of clinical variability and perhaps genetic heterogeneity in Seckel syndrome. Our results demonstrate that cross-link sensitivity comparable to FA is not a uniform finding in patients with Seckel syndrome. ( info) |
5/248. Fludarabine-based protocol for human umbilical cord blood transplantation in children with fanconi anemia. PURPOSE: A novel conditioning regimen of fludarabine monophosphate (FLM), anti-T-lymphocyte globulin (ATG), and low-dose cyclophosphamide with no irradiation for human umbilical cord blood transplantation (HUCBT) for the treatment of fanconi anemia (FA) is described. PATIENT AND methods: A 12-year-old girl with FA received a human umbilical cord blood transplant from a fully matched sibling donor. After the HUCBT, the patient was given granulocyte colony stimulating factor in combination with erythropoietin. Pretransplant conditioning consisted of FLM (30 mg/m2/d) from day -10 to day -5, cyclophosphamide (10 mg/kg/d) on day -7 and -6, and rabbit ATG (ATG-Frasenius, 10 mg/kg/d) from day -4 to day -1. Cyclosporin A (3 mg/kg/d) was administered from day -1 as graft-versus-host disease prophylaxis. Cord blood from a sibling donor was used as a source of hematopoietic stem cells. RESULTS: Engraftment was normal and sustained. The regimen was well tolerated with very mild toxicity and no major transplant-related complications or >grade II graft-versus-host disease. chimerism was 100% donor origin as determined by restriction fragment length polymorphism. CONCLUSIONS: It is possible to achieve sustained engraftment and only mild toxicity in FA after HUCBT with a conditioning regimen of FLM, ATG, and cyclophosphamide with no irradiation. These preliminary results with this novel conditioning protocol are encouraging and should be evaluated in a larger group of patients with FA undergoing HUCBT. ( info) |
6/248. A microdeletion syndrome due to a 3-Mb deletion on 19q13.2--diamond-Blackfan anemia associated with macrocephaly, hypotonia, and psychomotor retardation. We report on a boy with congenital pure red blood cell aplasia [diamond Blackfan anemia (DBA)] and severe congenital hypotonia, macrocephaly, hypertelorism, a broad and tall forehead, medial epicanthus, and facial hypotonia with mouth-breathing and drooling, an affable and out-going personality, and a general psychomotor retardation. These features show similarity to the phenotype of the X-linked FG syndrome. DBA was diagnosed at the age of 4 months, and the boy underwent treatment with transfusion and with prednisolone. He had a normal 46, XY karyotype, but fluorescence in situ hybridization (FISH) analysis to metaphase chromosomes revealed a 3-Mb deletion on 19q13.2. This chromosomal region has previously been linked to the DBA phenotype and one 19q13 microdeletion has been identified in a patient with DBA. This deletion coincides with the deletion reported here. We suggest that the complex phenotype of our patient, including both DBA and the associated features, represent a microdeletion syndrome. ( info) |
7/248. Delayed engraftment and mixed chimerism after HLA-identical sibling donor BMT in Fanconi anaemia. A 12-year-old girl with Fanconi anaemia (FA) received a bone marrow transplant from her HLA-identical brother following conditioning with cyclophosphamide (20 mg/kg), thoraco-abdominal radiation (TAI) (4 Gy) and equine anti-thymocyte globulin (ATG) (90 mg/kg). Engraftment was delayed and initially tenuous, and was followed by mixed chimerism (MC) over a follow-up period of 2 years. dna analysis of engraftment was performed on whole peripheral blood and on separated granulocytes, B and T lymphocytes using PCR detection of CA tandem repeat polymorphisms. At 10 weeks post BMT, granulocytes were predominantly donor, but B and T lymphocytes recipient, in origin. Over the subsequent 90 weeks, granulocytes and B lymphocytes were donor-derived, whilst T cells showed persistent MC but with an increasing donor component. Marrow haemopoietic function (Hb, ANC and platelet count) improved gradually in parallel with a rise in the proportion of donor lymphocyte engraftment. We postulate that a population of recipient lymphocytes survived conditioning and in turn delayed the development of full donor chimerism. Although transient MC has been described after allogeneic BMT in FA, its association with delayed engraftment, and persistence for more than 1 year post BMT, has not been documented clearly. ( info) |
8/248. Failure of allogeneic bone marrow transplantation to correct diamond-Blackfan anaemia despite haemopoietic stem cell engraftment. We report the case of a 10-year-old boy with congenital pure red cell aplasia (diamond-Blackfan anaemia) who received an allogeneic bone marrow transplant (BMT) from his HLA-identical sister. The transplant was complicated by moderate veno-occlusive disease (VOD). Despite cytogenetic evidence of complete donor haemopoietic stem cell engraftment there was selective failure of red cell engraftment and he remains red cell transfusion-dependent. This is the first case of a stem cell transplant failing to correct the defect in this condition despite engraftment. ( info) |
9/248. pregnancy in bone marrow failure syndromes: diamond-Blackfan anaemia and Shwachman-diamond syndrome. pregnancy in bone marrow failure syndromes has risk to mother and fetus. There are fewer than 30 reports of cases with diamond-Blackfan anaemia (DBA), and none with Shwachman-diamond syndrome (SD). We report two DBA and one SD cases. One DBA mother received transfusions intra-partum, and the other only post-partum. Both required caesarean sections (C-sections) for failure of labour to progress and severe pre-eclampsia respectively. Both subsequently resumed pre-pregnancy steroid-induced control of anaemia. approximately 40% of DBA pregnancies required maternal transfusions; 25% delivered by C-section. The SD patient also had Ehlers-Danlos (ED) syndrome and urticaria pigmentosa (UP). Her blood counts were adequate until week 38, when the platelet count dropped and a C-section was performed. pregnancy management in marrow failure disorders requires obstetricians with expertise in high-risk pregnancies, and haematologists with experience with marrow failure syndromes. ( info) |
10/248. Congenital hypoplastic anaemia in a patient with a new multiple congenital anomalies-mental retardation syndrome. We report on a girl with congenital hypoplastic anaemia, "coarse" face, generalized hypertrichosis with scalp hypotrichosis, short fifth finger, hypoplastic toenails, and mental retardation. A sister of the proposita, who died at the age of 1 year, had severe congenital anaemia, hypoplastic fingernails, low birth weight, failure to thrive, and repeated upper respiratory tract infections. Based on family history, we suspect that hypoplastic anaemia and the same multiple congenital anomalies-mental retardation syndrome (MCA/MR) were also present in this sister. To the best of our knowledge, this patient represents the first report of congenital hypoplastic anaemia and such a complex MCA/MR syndrome, probably inherited as an autosomal recessive trait. ( info) |