The rare translocation t(14;21)(q11;q22) detected in a Moroccan patient with T-cell acute lymphoblastic leukemia.

Cytogenetic studies of acute lymphoblastic leukemia have been at the forefront of research in the pathogenesis of cancer. The presence of recurring chromosomal abnormalities (either numeral or structural rearrangements) provides immediate clues to the genetic events leading to leukemia and many abnormalities have important prognostic significance. The rare translocation t(14,21)(q11.2;q22) has been described in pediatric T lineage ALL in only one case so far in 2000. The present study is a case report of an ALL case in which we found a t(14,21)(q11.2;q22) as a non random chromosomal abnormality among 70 analyzed pediatric ALL cases referred exclusively to BIOLAB Laboratory from the children hospital of Morocco.

First report on the Moroccan registry of primary immunodeficiencies: 15 years of experience (1998-2012).

PURPOSE: Primary immunodeficiencies (PIDs) are a large group of diseases characterized by susceptibility to infections. We provide the first comprehensive report on PIDs in Morocco, the epidemiological, clinical, etiological and outcome features which have never before been described. METHODS: A national registry was established in 2008, grouping together data for PID patients diagnosed since 1998. RESULTS: In total, 421 patients were diagnosed between 1998 and 2012. Parental consanguinity was common (recorded for 43.2 % of patients) and the median time to diagnosis was 2.0 years. Overall, 27.4 % of patients were considered to have well defined syndromes with immunodeficiency (48 cases of hyper-IgE syndrome and 40 of ataxia-telangiectasia); 22.7 % had predominantly antibody deficiencies (29 cases of agammaglobulinemia and 24 of CVID); 20.6 % had combined immunodeficiencies (37 cases of SCID and 26 of MHC II deficiencies) and 17.5 % had phagocyte disorders (14 cases of SCN and 10 of CGD). The principal clinical signs were lower respiratory tract infections (60.8 %), skin infections (33.5 %) and candidiasis (26.1 %). Mortality reached 28.8 %, and only ten patients underwent bone marrow transplantation. We analyzed the impact on mortality of residence, family history, parental consanguinity, date of diagnosis and time to diagnosis, but only date of diagnosis had a significant effect. CONCLUSIONS: The observed prevalence of PID was 0.81/100,000 inhabitants, suggesting considerable underdiagnosis and a need to increase awareness of these conditions in Morocco. The distribution of PIDs was different from that reported in Western countries, with a particularly high proportion of SCID, MHC II deficiencies, hyper-IgE syndrome and autosomal recessive agammaglobulinemia. However, we have now organized a national network, which should improve diagnosis rates in remote regions.

Molecular defects in Moroccan patients with ataxia-telangiectasia.

Ataxia-telangiectasia (AT) is a rare autosomal recessive disease, affecting neurologic and immune system. Numerous mutations are described in the ATM gene in several populations. However, in Morocco, few data are available concerning this condition. Our main goal is to determine clinical, immunological, and molecular presentation of Moroccan patients with AT. We screened 27 patients, out of 22 unrelated families, for ATM gene mutations. All our patients showed ataxia, ocular telangiectasia, and immunodeficiency, as well as elevated serum alphafetoprotein levels. Mean age at diagnosis was 5.51 years, and consanguinity rate was 81.8 %. Mean age at onset was 2.02 years, and mean time to diagnosis was 3.68 years. We found 14 different mutations in 19 unrelated families, of which 7 were not reported. Our results showed that c.5644C>T mutation was the most common in our series. However, further studies are required to demonstrate a founder effects on ATM gene in Moroccan patients, who showed mutational heterogeneity otherwise. Our data indicate that direct sequencing of coding exons is sufficient for a high detection rate in ATM in Moroccan population.

[Thymic hyperplasia following treatment for nephroblastoma]. / Hypertrophie thymique après une chimiothérapie pour un néphroblastome.

UNLABELLED: Thymic hyperplasia in response to stress is a well known phenomenon. Thymic hyperplasia has also been described after chemotherapeutic treatment for malignancies in children. CASE REPORT: A three-year-old girl was followed up from the age of 18 months for a left kidney nephroblastoma treated by combination of chemotherapy (vincristin, actinomycin and adriamycin) and surgery. Assessment at the end of treatment was normal. Four months after the end of treatment, pulmonary radiography showed mediastinal enlargement, which was shown to originate in the thymus at thoracic CT scan. A recurrence of the disease was suspected. Biopsy showed thymic hyperplasia without evidence of tumor cells. Mediastinal enlargement then disappeared spontaneously 2 months later. CONCLUSION: Thymic hyperplasia occurring during remission of a cancer treated by chemotherapy is a diagnostic dilemma as it suggests mediastinal reccurence of the disease. Needle aspiration cytology is an appropriate investigation in thymic hyperplasia. No steroid therapy should be used before histologic diagnosis of thymic hyperplasia.

[Clear cell sarcoma of the kidney. A study of 13 cases]. / Sarcome rénal à cellules claires. A propos d'une série de 13 cas.

UNLABELLED: Clear cell sarcoma of the kidney (CCSK) also called a "bone-metastasizing renal tumor of childhood" is the second common pediatric renal neoplasm. This tumor is associated with a higher rate of relapse and a wider distribution of metastases than Wilms' tumor. PATIENTS AND METHODS: We have reviewed records of 13 cases of CCSK among 277 renal tumors (5%) diagnosed at the children's hospital of Rabat between 1990 and 2002. RESULTS: The median age at diagnosis was 14 months (5 months-9 years). The male to female ratio was 5.5:1.00. Abdominal mass, usually the first physical finding, was associated with hematuria in four cases. No congenital malformation syndrome or familial Wilms' tumor were observed. Imaging studies found out seven right and six left intrarenal processes. Preoperative chemotherapy was given according to the SIOP9, SIOP93-01 and GFAOP 98 protocols. Twelve of 13 children underwent nephrectomy. Tumor measurements varied through 450-3450 g and 7-26 cm. The classic morphologic pattern was seen in nine cases (69%). The distribution local stage was I: three cases; II: three cases; III: six cases; IV: one case. Postoperative chemotherapy and radiotherapy (21 600-30 600 cGy) was done in 10 cases. With a median follow up of 44 months, four patients showed bone metastases (31%), four are alive in CR, four are lost for follow up and five died. CONCLUSION: CCSK remains the pediatric renal tumor most frequently misdiagnosed. Its aggressiveness and its ability to give bone metastases need to recognize early this diagnosis for an adapted treatment.

[Non-Hodgkin's lymphoma with protein S deficiency]. / Lymphome non hodgkinien associé à un déficit en protéine S.

Venous thrombosis is rare in children. It can be either acquired or of constitutional origin. Thrombosis during non-Hodgkin lymphoma remains exceptional and is usually locally associated to the tumoral process, raising the issue of its tumoral or cruoric nature. The treatment is based on anticoagulation concomitantly to chemotherapy. We report on a 4-year-old boy admitted for mediastinal non-Hodgkin lymphoma, who developed a thrombosis of the superior vena cava associated to protein S-deficiency. The mechanism of thrombosis may have been multifactorial: associated protein S-deficiency, vascular compression, tumoral process and chemotherapy.

Streptococcal reporter gene-fusion vector for identification of in vivo expressed genes.

To study streptococcal genes that are specifically induced in the host during endocarditis, we have developed a novel plasmid for use in in vivo expression technology (IVET). This IVET uses an integration plasmid, pAK36, that carries dual (amy-cat) reporter genes. A gene-fusion strain library was constructed with the plasmid randomly inserted into the chromosome of Streptococcus gordonii V288 by insertion-duplication. The library was inoculated intravenously into a rabbit that had been prepared for experimental endocarditis. Beginning 6 h after the inoculation, the rabbit was given chloramphenicol (Cm) intravenously twice a day to a final serum level of 5 microg/ml and was euthanized 3 days later. The aortic valve vegetations containing Cm(R) S. gordonii clones were cultured. Colonies were screened in vitro for negative amylase activity and sensitivity to Cm. Forty-eight such colonies showed 13 different insertion patterns when Southern hybridization blots were probed with labeled pAK36. For each of the 13 isolates, the gene fragment proximal to the insertion of the reporter amy-cat was cloned, and its nucleotide sequence was determined. Functions of these genes were inferred by their homology to known genes. Therefore, this novel IVET vector can be useful for identification of in vivo induced genes in S. gordonii and other streptococcal species.