PubMed Health⌕ Search

Biomedical subjects

A Vlachos

Publications and source records attributed to A Vlachos.

12 recordsLinked to original sources

Paucity of Sjogren-like syndrome in a cohort of HIV-1-positive patients in the HAART era. Part II.

OBJECTIVE: This study was performed in order to investigate the prevalence of Sjögren-like syndrome (SLS) in the highly active anti-retroviral therapy (HAART) era in a cohort of HIV-1-positive Greek patients. METHODS: One hundred and thirty-one unselected patients were screened by the validated European Union (EU) criteria for Sjögren's syndrome. Of the 31 who gave a positive EU-validated questionnaire, 17 consented to undergo minor salivary gland biopsy and other tests. RESULTS: Only two patients had a positive salivary gland biopsy and both belonged to the non-compliant HAART group, whereas none of the compliant HAART patients had histological findings. CONCLUSIONS: It is concluded that SLS, the prevalence of which in the pre-HAART era was 7.8%, has disappeared, possibly as a result of the protective action of HAART.

Adult↗

Bilateral microtia and cleft palate in cousins with Diamond-Blackfan anemia.

We report on maternal first cousins with bilateral microtia, micrognathia, cleft palate and hematologic findings of Diamond-Blackfan anemia (DBA). The similarity of findings shared between our cases and a female reported by Hasan and Inoue [1993] suggests that this is a distinctive syndrome, rather than a chance association. DBA is a heterogeneous disorder, caused in about 25% of cases by heterozygous mutations in the RPS19 gene (DBA1). Mutation analysis in our cases did not show an RPS19 mutation, and 2 alleles were present in each. Segregation analysis for DBA1 on chromosome 19 and DBA2 on 8p23 was not consistent with linkage. We conclude that this syndrome of microtia, cleft palate and DBA is not allelic to known DBA loci.

Abnormalities, Multiple↗

Evidence for linkage of familial Diamond-Blackfan anemia to chromosome 8p23.3-p22 and for non-19q non-8p disease.

Diamond-Blackfan anemia (DBA) is a rare congenital hypoplastic anemia that usually presents early in infancy and is inherited in 10% to 20% of cases. Linkage analysis has shown that DBA in many of both dominant and recessive DBA families mapped to chromosome 19q13.2 leading to the cloning of a gene on chromosome 19q13.2 that encodes a ribosomal protein, RPS19. However, subsequently, mutations of the RPS19 gene have only been identified in 25% of all patients with DBA. This study analyzed 14 multiplex DBA families, 9 of which had 19q13.2 haplotypes inconsistent with 19q linkage. A genome-wide search for linked loci suggested the presence of a second DBA locus in a 26.4-centimorgan (cM) interval on human chromosome 8p. Subsequently, 24 additional DBA families were ascertained and all 38 families were analyzed with additional polymorphic markers on chromosome 8p. In total, 18 of 38 families were consistent with linkage to chromosome 8p with a maximal LOD score with heterogeneity of 3.55 at D8S277 assuming 90% penetrance. The results indicate the existence of a second DBA gene in the 26.4-cM telomeric region of human chromosome 8p23.3-p22, most likely within an 8.1-cM interval flanked by D8S518 and D8S1825. Seven families were inconsistent with linkage to 8p or 19q and did not reveal mutations in the RPS19 gene, suggesting further genetic heterogeneity. (Blood. 2001;97:2145-2150)

Chromosomes, Human, Pair 19↗

Hematopoietic stem cell transplantation for Diamond Blackfan anemia: a report from the Diamond Blackfan Anemia Registry.

The Diamond Blackfan Anemia (DBA) Registry of North America is a detailed database of patients with DBA from the United States and Canada. To date, 354 patients have been registered. From this database an analysis of the outcome of hematopoietic stem cell transplantation for DBA was undertaken. Of the 20 transplanted patients who met criteria for the diagnosis of DBA, eight underwent an allogeneic HLA-matched sibling hematopoietic stem cell transplant (SCT) and 12 an alternative donor SCT. The median age at transplant for all patients was 6 years 2 months; 3 years 10 months vs 9 years 1 month for HLA-matched sibling and alternative donor SCT, respectively. All of the HLA-matched sibling transplants were done using a non-irradiation-containing regimen, whereas the majority of alternative donor transplants were performed using total body irradiation. The survival for HLA-matched sibling vsalternative donor transplant was 87.5% +/- 11.7% vs 14.1% +/- 12.1% at greater than 5 years from SCT (P = 0.015). The use of HLA-matched sibling SCT should be considered for all patients with suitable donors. However, alternative donor SCT in DBA must be approached cautiously, the potential for severe aplastic anemia (SAA) or hematopoietic malignancy not withstanding.

Adolescent↗

Osteogenic sarcoma associated with Diamond-Blackfan anemia: a report from the Diamond-Blackfan Anemia Registry.

PURPOSE: Diamond-Blackfan anemia (DBA) is a congenital pure red cell aplasia, usually presenting in infancy or early childhood. A review of the literature strongly supports a predisposition to hematopoietic malignancy. Recently, solid tumors have been reported, some attributable to hemosiderosis and/or androgen therapy. Two cases of osteogenic sarcoma have also been documented. An analysis from the Diamond-Blackfan Anemia Registry was performed to evaluate the cancer risk in patients with DBA. METHODS: The Diamond-Blackfan Anemia Registry of North America (DBAR) is a comprehensive database of patients with DBA enrolled, after informed consent, through outreach to pediatric hematologists and family groups. The patients and/or their families complete a detailed questionnaire, and a review of medical records and telephone interviews are performed to complete and clarify the information provided. RESULTS: Of the 354 patients registered in the DBAR, there were six patients meeting the accepted diagnostic criteria for DBA who were found to have malignancies. Three patients had osteogenic sarcoma diagnosed, one with myelodysplastic syndrome, one with colon carcinoma, and one with a soft tissue sarcoma. CONCLUSION: There appears to be an association of osteogenic sarcoma with DBA. A young age at presentation may be a feature of DBA-associated osteogenic sarcoma. Because of the immaturity of the database, the actuarial risk for osteogenic sarcoma and other cancers in individuals with DBA cannot be ascertained. Speculation is made regarding the nature of the molecular defect leading to the association of DBA and osteogenic sarcoma.

Adolescent↗

Interphase FISH analysis of sex-mismatched BMT utilizing dual color XY probes.

Interphase FISH analysis, utilizing dual color XY probes, was performed on 27 patients following allogeneic sex-mismatched bone marrow transplantation and on 31 controls. Of the 123 167 examined interphase nuclei, 63 318 were from 19 of the 21 patients (54 specimens) who engrafted, 31 827 from five of the six patients (29 specimens) who relapsed (four) or failed to engraft (one) and 24 703 from the 31 control specimens. In patients who engrafted, the mean percentage of host cells was 0.26% between day 29 and 5 years following BMT. Microchimerism of 0.7% or less than 1-5 years following BMT was not predictive of relapse. Interphase FISH analysis predicted relapse or failure of engraftment in five of the six evaluable patients. In three of five patients both conventional cytogenetics and interphase FISH of bone marrow cells provided important information regarding engraftment status and degree of chimerism.

Bone Marrow Transplantation↗

Evidence for the embryonic origin of partial chromosome 7 deletion in monozygotic twins with juvenile chronic myelogenous leukemia.

During donor evaluation for allogeneic bone marrow transplantation (BMT) of a 28-month-old child with juvenile chronic myelogeneous leukemia (JCML) with 46,XY,-7,+mar karyotype, the potential donor twin brother was found to be thrombocytopenic. Subsequent genotype analysis determined monozygosity with 98% probability. Bone marrow analysis of the twin brother revealed the same 46,XY,-7,+mar karyotype and a diagnosis of JCML was made. Metaphase FISH studies documented that mar chromosome in both twins contains the pericentromeric region of chromosome 7 and thus both twins had a partial monosomy of chromosome 7. A possible embryonic origin of del(7) is proposed.

Antineoplastic Agents↗

Disparate lympho-erythroid donor to recipient chimaerism in a beta(0)-thalassaemia bone marrow transplant recipient with red cell indices indicative of apparent full engraftment.

A 4-year-old girl with transfusion-dependent beta(0)-thalassaemia received an HLA-identical bone marrow transplant (BMT) from her beta(0)-thalassaemia trait sister. Prior to BMT, chromosomal analysis revealed the recipient to have 46,XX,9qh+, a polymorphic variant of the heterochromatin region of chromosome 9, which her donor did not have. Within 1 month post-BMT, 89% of nucleated bone marrow cells were of donor origin. One year later, donor engraftment had decreased to 44% and 34% in nucleated bone marrow cells and blood lymphocytes, respectively. By 2 years, donor lymphocyte engraftment fell to 5%, raising concern of possible graft rejection. To examine erythroid chimaerism, globin synthesis by individual erythroid progenitor cell derived colonies (BFU-E) was analysed. On days 1000 and 1130 post-BMT, 79% and 77% of colonies, respectively, synthesized beta-globin and therefore were of donor origin.

Bone Marrow Transplantation↗

A new syndrome of familial aplastic anemia and chronic liver disease.

This report describes a new familial syndrome characterized by a combination of bone marrow failure and chronic liver disease. This disorder appears to be genetic in origin with an autosomal dominant inheritance and was characterized by hyperactivity of the immune system with increased activated cytotoxic T lymphocytes in peripheral blood and bone marrow and the presence of gamma-interferon messenger RNA in bone marrow of several cases.

Adolescent↗

Bone marrow failure in children.

Bone marrow failure in the pediatric patient places the hematologist at the junction of clinical medicine, cellular biology, and molecular genetics. The pathophysiology of these disorders is rapidly being elucidated in many laboratories. Treatments such as bone marrow transplantation and the nascent modality of gene therapy are firmly grounded in these modern sciences. This year's progress in the understanding, diagnosis, and treatment of a wide variety of predominantly pediatric bone marrow failure states is a direct result of the union between the "laboratory bench and the patient bedside."

Anemia, Aplastic↗

The Diamond Blackfan Anemia Registry: tool for investigating the epidemiology and biology of Diamond-Blackfan anemia.

Diamond-Blackfan anemia (DBA) is a heterogeneous genetic disorder characterized by red cell aplasia and congenital anomalies. One of what appears to be multiple DBA genes has been cloned. Affected individuals in the same family may vary dramatically as to the degree of anemia, response to corticosteroids, and the presence of congenital anomalies. The epidemiology of DBA has been gleaned largely from literature reviews. This approach is limited because of the two-fold disadvantage of the reporting bias inherent in the literature and the lack of an active patient database. The Diamond Blackfan Anemia Registry of North America (DBAR) is designed to overcome these disadvantages to study the epidemiology and biology of DBA. The DBAR is a comprehensive database of patients with DBA who are enrolled after informed consent is obtained. Identification of patients is made through outreach to pediatric and adult hematologists and the Diamond Blackfan Anemia Foundation. The patients and/or their families complete a detailed questionnaire. A review of medical records and telephone interviews are performed to complete and clarify the information provided. To date, 354 patients have been enrolled in the DBAR. Using this database, important epidemiologic, clinical, and laboratory observations have been made with regard to the clinical presentation, the inheritance of DBA, the genetics of congenital malformations, the therapeutic outcome, including the efficacy of hematopoietic stem cell transplantation, and the recognition of DBA as a cancer predisposition syndrome. In particular, the database is an essential substrate for DBA gene discovery.

Child↗