UGT1A1 (TA)n Promoter Genotype: Diagnostic and Population Pharmacogenetic Marker in Serbia.

The UGT1A1 enzyme is involved in the metabolism of bilirubin and numerous medications. Unconjugated hyperbilirubinemia, commonly presented as Gilbert syndrome (GS), is a result of decreased activity of the UGT1A1 enzyme, variable number of TA repeats in the promoter of the UGT1A1 gene affects enzyme activity. Seven and eight TA repeats cause a decrease of UGT1A1 activity and risk GS alleles, while six TA repeats contribute to normal UGT1A1 activity and non-risk GS allele. Also, the UGT1A1 (TA)n promoter genotype is recognized as a clinically relevant pharmacogenetic marker. The aim of this study was to assess diagnostic value of UGT1A1 (TA)n promoter genotyping in pediatric GS patients. Correlation of the UGT1A1 (TA)n genotypes and level of unconjugated bilirubin at diagnosis and after hypocaloric and phenobarbitone tests in these patients was analyzed. Another aim of the study was to assess pharmacogenetic potential of UGT1A1 (TA)n variants in Serbia. Fifty-one pediatric GS patients and 100 healthy individuals were genotyped using different methodologies, polymerase chain reaction (PCR) followed by acrylamide electrophoresis, fragment length analysis and/or DNA sequencing. Concordance of the UGT1A1 (TA)n promoter risk GS genotypes with GS was found in 80.0% of patients. Therefore, UGT1A1 (TA)n promoter genotyping is not a reliable genetic test for GS, but it is useful for differential diagnosis of diseases associated with hyperbilirubinemia. Level of bilirubin in pediatric GS patients at diagnosis was UGT1A1 (TA)n promoter genotype-dependent. We found that the frequency of pharmacogenetic relevant UGT1A1 (TA)n promoter genotypes was 63.0%, pointing out that UGT1A1 (TA)n promoter genotyping could be recommended for preemptive pharmacogenetic testing in Serbia.

Glucocorticoid-resistant Evans' syndrome successfully controlled with low-dose cyclosporine.

OBJECTIVE: To present a patient suffering from Evans' syndrome (ES), whose bouts of severe cytopenia were prevented by low-dose cyclosporine maintenance therapy. CASE SUMMARY: A boy suffering from frequent mild respiratory infections, first time evaluated in a tertiary care pediatric center at age 4, was found to have lymphadenopathy and mild splenomegaly. The thrombocytopenia was first noted at age 6. He was diagnosed to have ES at the age of 8, during another bout of thrombocytopenia, this time associated with Coombs-positive hemolytic anemia. Immunoglobulin concentration in the plasma was measured repeatedly, and was in the normal range, or even increased. Lymphocyte subpopulation numbers were in the normal range, with decreased CD4+/ CD8+ ratio (0.6). Autoimmune lymphoproliferative syndrome was excluded by the absence of CD4-CD8- T lymphocytes. Since the patient failed to respond to standard therapy with prednisolon 2 mg/kg, high dose intravenous methylprednisolone (10 mg/ kg/d for 3 days) and high dose intravenous immunoglobulin (1 g/kg/d for 2 days), cyclosporine treatment was initiated (6 mg/ kg/d) and resulted in normalization of platelet count and resolution of hemolysis. Two attempts to withdraw cyclosporine therapy resulted in life-threatening hemolytic crisis with severe thrombocytopenia, requiring the re-institution of cyclosporine. The dose of cyclosporine was eventually tapered to the present 0.5 mg/kg, corresponding to drug serum levels of 5 - 8 mg/ml. The patient is now free of manifestations of Evans' syndrome but, after 20 years of cyclosporine treatment, has slightly impaired kidney function. CONCLUSION: Low-dose cyclosporine therapy given to our patient appears to have subdued the autoimmune process thought to underlie the manifestations of ES, albeit at the cost of some toxicity to the kidneys.

Clinical features of the most common fusion genes in childhood acute lymphoblastic leukemia.

Contemporary protocols ensure high-remission rate and long-term free survival in children with acute lymphoblastic leukemia (ALL), but small percentage of patients is still incurable. Molecular genetic methods helped to establish submicroscopic classification as well as minimal residual disease follow-up, considered to be responsible for relapse. Our study enrolled 70 pediatric patients with de novo ALL, analyzed using reverse transcriptase-polymerase chain reaction for the presence of four major risk-stratifying translocations (BCR/ABL, MLL/AF4, TEL/AML1, and E2A/PBX1). Bone marrow samples were collected at diagnosis, at the end of induction phase, and after intensive chemotherapy with the aim to establish the correlation between chromosomal aberration, clinical features, and treatment response. Presenting the results of this study, we offer another evidence of variable incidence and clinical characteristics of ALL subtypes.

[Successful treatment of second hepatoblastoma relapse--case report].

INTRODUCTION: The prognosis of hepatoblastoma has changed since effective adjuvant chemotherapy had been introduced in 1980's. There is a general agreement that complete resection is the cornerstone of treatment for children with hepapatoblastoma and the only way for eventual cure. CASE REPORT: We describe a boy with relapsed hepatoblastoma presenting with elevated -fetoprotein (AFP) and no visible tumor by ultrasound and computed tomography (CT). The relapse was treated with chemotherapy. Second relapse occurred shortly after therapy was completed, but this time we waited for tumor mass to appear. Combined surgery and chemotherapy resulted in remission status with 48 months of follow up. CONCLUSION: Hepatoblastoma relapse without evidence of tumor is not unusual but its treatment remains controversial. Radiological investigations should be repeated until site of relapse is identified. Based on our experience it seems of no benefit to treat isolated elevation of AFP.

Molecular basis of thalassemia syndromes in Serbia and Montenegro.

This study reports the molecular characterization of thalassemia syndromes in Serbian and Montenegrin populations. We identified eight beta-thalassemia mutations [codon 39 (C-->T), IVS-I-110 (G-->A), IVS-II-745 (C-->G), codon 44 (-C), -87 (C-->G), IVS-II-1 (G-->A), IVS-I-6 (T-->C), IVS I-1 (G-->A)] in 70 members of 29 families using polymerase chain reaction, reverse dot blot, amplification refractory mutation system and direct sequencing analysis. Hemoglobin (Hb) Lepore was found to be the most common cause of the thalassemia phenotype. Hb Sabine and alpha-thalassemia were detected as well. We also studied beta-globin gene cluster haplotypes and their association with the most common mutations. A novel haplotype associated with the Hb Lepore gene was identified. The results presented herein allowed the implementation of a prenatal diagnosis program in Serbia and Montenegro.

[Major and minor congenital anomalies in children with Wilms' tumor]. / Kongenitalne major i minor anomalije kod dece sa Wilm'sovim tumorom.

Wilms's tumour is a paediatric tumour of hereditary origin in 40% of cases. In children with Wilms's tumour associated congenital anomalies are frequent, particularly congenital anomalies of the kidney and urogenital tract. Over the period from 1972 to 1987 the authors carried out a prospective study and systematically investigated congenital major and minor anomalies in 24 children with Wilms's tumour. They revealed the presence of aniridia, bilateral cataract and cryptorchidism in 1/24 children, mental retardation, small stigated congenital major and minor anomalies in 40 chidism in 1/40 children, mental retardation, small stature and a cystic kidney in 1/40, mental retardation in 3/40. A detailed investigation of minor anomalies confirmed the presence of 2 to 3 anomalies in all observed children. Cytogenetic investigation was performed in all children. Only in a child with aniridia Wilms's tumour a cytogenetic anomaly, 11p deletion, was found.