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Introduction: Fanconi anemia (FA) is a genetically and phenotypically heterogeneous inherited disease. Many groups have established FA registries. In Tunisia, in collaboration with the Tunisian Fanconi Anemia Study Group (TFASG), we set up the Tunisian Fanconi Anemia Registry (TFAR)., Patients and Methods: We contacted all hematology and pediatrics departments to include their FA patients diagnosed between January 1983 and December 2008. The registry is available on the TFASG web site (www.fanconi-tunisie.net)., Results: Sorting the files brought out 142 patients belonging to 118 families. The mean age at diagnosis was 11 years. There was consanguinity in 86%, malformative syndrome in 91%, and pancytopenia at diagnosis in 69%. Of 28 patients, 95% belonged to the FANCA group. Androgen treatment was given in 109 cases and genoidentical bone marrow transplantation (BMT) in 27 patients. The diagnosis of a myelodysplastic syndrome was retained in 4%, acute leukemia in 6%, and a solid tumor in 2%. The median overall survival time in all patients is 17 years 5 months; it is significantly better in patients having received allografts (p=0.01)., Conclusion: FA seems frequent in Tunisia, which is in part explained by the high consanguinity and endogamy in this country. Hematologic impairment is still the most frequent revealing circumstance of the disease. It is often severe or moderate and requires androgen treatment or bone marrow transplantation. BMT should be proposed to all patients with an HLA-compatible donor., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

The intracardiac ectopic thyroid tumour is rare. We report the case of a woman who was admitted for exertional dyspnea. The echocardiography revealed an obstructive tumor in the right ventricular outflow tract. Histological examination of the removed tumour showed the ectopic follicular thyroid tissue., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

The optimal management of malignant haematological disorders depend on the degree of tumor load reduction after therapy. Chronic myeloid leukemia constitutes a clinical model for molecular detection and therapy surveillance of malignant disease since this entity was the first leukemia shown to be associated with a specific bcr-abl fusion gene in the patient's leukemia cells. Molecular monitoring of bcr-abl transcript levels by real-time quantitative PCR is increasingly used to assess treatment response in patients with chronic myeloid leukemia (CML). This has become particularly relevant in the era of imatinib therapy when residual levels of leukaemia usually fall below the level of detection by bone marrow cytogenetic analysis. We monitored bcr-abl transcript levels by quantitative real time PCR in 50 tunisian patients treated with imatinib for chronic myeloid leukemia in chronic phase for a median of 29 months (3-60) after they started imatinib.

From April 2003 to December 2006, 195 patients with de novo symptomatic myeloma and younger than 60 years of age were randomly assigned to receive either tandem transplantation up front (arm A, n = 97) or one autologous stem-cell transplantation followed by a maintenance therapy with thalidomide (day + 90, 100 mg per day during 6 months) (arm B, n = 98). Patients included in arm B received a second transplant at disease progression. In both arms, autologous stem-cell transplantation was preceded by first-line therapy with thalidomide-dexamethasone and subsequent collection of peripheral blood stem cells with high-dose cyclophosphamide (4 g/m(2)) and granulocyte colony stimulating factor. Data were analyzed on an intent-to-treat basis. With a median follow-up of 33 months (range, 6-46 months), the 3-year overall survival was 65% in arm A and 85% in arm B (P = .04). The 3-year progression-free survival was 57% in arm A and 85% in arm B (P = .02). Up-front single autologous transplantation followed by 6 months of maintenance therapy with thalidomide (with second transplant in reserve for relapse or progression) is an effective therapeutic strategy to treat multiple myeloma patients and appears superior to tandem transplant in this setting. This study was registered at www.ClinicalTrials.gov as (NCT 00207805).

Human interferon α2b gene was cloned in the methylotrophic yeast Pichia pastoris under the control of the AOX1 methanol inducible promoter. To optimise the volumetric productivity, we performed different fed-batch studies in a 5-L bioreactor. We demonstrated that hIFNα2b was highly sensitive to proteases activity during high cell density culture. The target protein was totally degraded 20h after the start of methanol feeding. Replacement of culture medium with fresh medium after glycerol fed-batch culture mode as well as medium enrichment with casamino acids at 0.1% and EDTA at 10mM, had significantly improved hIFNα2b expression and prevented its proteolysis. Moreover, to further improve hIFNα2b production, three different methanol fed-batch strategies had been assayed in high cell density culture. The optimal strategy resulted in a production level of 600mg/l while residual methanol level was maintained below 2g/l. Clarification of culture supernatant through a 0.1μm hollow fiber cartridge showed that almost 95% of the target protein was retained within the retentate. Triton X-100 or NaCl addition to the culture harvest before microfiltration had improved the recovery yield of this step. rhIFNα2b was further purified by cation exchange on Sepharose SP resin followed by gel permeation on Sephacryl S-100. The overall yield of the process was equal to 30% (180mg/l). The biological activity of the purified protein based on the antiviral activity test was 1.5×10(8)IU/mg. The optimised process has a great potential for large scale production of fully functional hIFNα2b.

Congenital antithrombin (AT) deficiency is the most thrombotic genetic abnormality of haemostasis. Total quantitative deficits are lethal as early as life intra-uterine. Only homozygous mutations concerning the heparin-binding site are compatible with life. We report here the case of an 18 years old patient with recurrent deep venous thrombosis of the inferior members. Haemostasis exploration shows a decreased AT activity (11%) in the presence of heparin while AT progressive activity and AT antigen are normal. Two other homozygous sisters are identified in this family study. Molecular study of AT gene show Arg47-Cys substitution, already reported in the literature with patients of different geographic origins. Treatment of patients with homozygous AT type HBS deficiency is similar that for patients with heterozygous AT deficiency; a continuous prophylactic anticoagulant treatment is always necessary and AT concentrates infusions are required in all situations needing curative heparin treatment.

Hypereosinophilic syndromes (HES) are a heterogenous group of rare disorders characterized by sustained and otherwise unexplained overproduction of eosinophils with organ involvement and consecutive dysfunction. Detection of the FIP1L1-PDGFRA fusion gene or the corresponding cryptic 4q12 deletion in HES supports the diagnosis of chronic eosinophilic leukemia (CEL) and provides a molecular explanation for the pathogenesis of this disorder. We screened seven Tunisian patients fulfilling the WHO criteria of HES for the presence of the FIP1L1-PDGFRA fusion gene using nested reverse transcription polymerase chain reaction on peripheral blood samples. Four of the seven patients were positive for this fusion gene. Sequence analysis revealed a substantial heterogeneity of the fusion transcripts due to the involvement of several FIP1L1 exons. All patients were male. The median age at diagnosis was 24 years (range, 18-50); one patient had a history of hypereosinophilia of more than 10 years. Two patients had clinically important and symptomatic eosinophilic endomyocardial disease with thrombotic events. Splenomegaly was constant in FIP1L1-PDGFRA positive CEL but not in the other HES patients (only 1/3).

Unlabelled: Pneumocystis Jiroveci pneumonia (PJP) is a rare opportunistic infection in immunodeficient patients in Tunisia, as well as in other Africain countries including those with a high prevalence of AIDS. In the literature, PJP has been reported in primary immunodeficiency diseases (PID) namely SCID T-B- or T-B+ or X-linked hyper-IgM syndrome., Objective: To evaluate the prevalence of PJP in the different PID observed in Tunisia., Patients and Methods: This retrospective study concerned 290 cases of PID confirmed by immunological investigation including the study of specific and/or non-pecific humoral and cellular immunity. The identification of P. Jiroveci in patients suspected of pneumocystosis was achieved by parasitological investigation in bronchoalveolar lavages., Results: A PID associated to a parasitologically confirmed pneumocystic infection was found in 9 out of 290 patients (3%) among whom the majority (7 patients) had an HLA class II combined immunodeficiency. The latter is an autosomic recessive disease which has been reported mainly in North African families. Indeed, this population is characterized by a high rate of consanguinity. Interestingly, no PJP has been observed neither in SCID T-B- or T-B+ nor in X-linked hyper-IgM syndrome., Discussion and Conclusion: PJP seems to be particularly frequent in HLA class II deficiency patients, since 7 out of 22 patients with this deficiency had a PJP (31%). Due to this defect, antigen presenting cells are unable to present the antigen to T lymphocytes demonstrating the critical role of CD4+ T lymphocytes responses in the immune response to this pathogen.

Increased affinity of Von Willebrand factor (VWF) for its platelet receptor GPIb-GPIX complex is responsible of an hemorrhagic disease, which is the Von Willebrand disease (VWD) type 2B when the molecular abnormality is located on the VWF, and the platelet-type 2B VWD when the mutation concern the platelet receptor. Haemostatic abnormalities in these bleeding disorders are similar; prolonged bleeding time, fluctuating thrombocytopenia, decreased factor VIII-VWF complex, and an increased response to low dose of ristocetin in platelets rich plasma. High molecular weight VWF multimers are decreased. We report here 2 cases of type 2B VWD and 1 case of platelet type 2B VWD. The distinction between these 2 diseases was established by studying platelet aggregation with weak doses of ristocetin in mixtures of washed platelets (of normal control or patient)+poor platelets plasma (normal or patient). In one case, VWD 2B was discovered late in a 49 years old man, and the factor VIIIC-VWF complex was not diminished. The distinction between these two congenital diseases is important for the treatment of bleeding manifestations which need VWF concentrates infusions in type 2B VWD and administration of platelets concentrates in pseudo type 2B VWD.

Here, we describe for the first time a Leishmania specific gene encoding a large 610 amino-acid RAB GTPase (LmLRAB). LmLRAB displays high homologies with the RAB GTPase protein family between amino acids 34 and 284. It contains characteristic signatures of RAB proteins: 4 GTP binding domains, 5 RAB specific domains, 3 RAB subfamily-specific domains, and a prenylation site. lmlrab is a single copy gene, transcribed as a 3.5 kb mRNA, highly conserved in Leishmania species, and encodes a protein doublet of approximately 75 kDa. Immunofluorescence microscopy using LmLRAB-specific antibodies demonstrated that LmLRAB is confined in a structure adjacent to the kinetoplast probably corresponding to an early endosomal/golgi apparatus localization. Interestingly, using quantitative real-time RT-PCR, we showed that the lmlrab gene is up-regulated twice in amastigotes relative to promastigotes. These findings suggest that LmLRAB may play a potential role in Leishmania pathogenicity.

We report two cases of atypical defibrination syndromes in patients with respectively acute monoblastic leukemia (chronic myeloid leukemia initially) and acute lymphoblastic leukemia. Hemostasis studies show low fibrinogen level, elevated D-dimers, decreased alpha 2 antiplasmin and factor V, normal antithrombin III values. Plasminogen is below the normal range in one patient. Soluble complexes, which are an important argument for diagnosis of intravascular coagulation disease, are not detected in both patients. Primary or secondary hyperfibrinolysis seems also excluded since euglobulin clot lysis time was normal. Enzymatic proteolysis of fibrinogen (or fibrin) by the blast cells has been reported by some authors; this mechanism could account for the hemostasis abnormalities observed in these two patients.

Behçet's disease is a systemic condition of unknown cause characterized in 20 to 40% of cases by venous and/or arterial thrombosis that is not fully explained by the hemostasis disorders reported in the literature. The present study investigated resistance to activated protein C in 65 Behçet's disease patients, 75 normal subjects, and 70 patients with a history of isolated thrombosis. The test used involved predilution in factor V-deficient plasma. Activated protein C resistance was found in six Behçet's disease patients (9.2%), eight normal subjects (10.6%), and 21 patients with isolated thrombosis (30%). Of the 26 Behçet's disease patients (40%) with a history of thrombosis, only one had activated protein C resistance. Activated protein C resistance does not explain the increased risk of thrombosis in Behçet's disease patients.

Background: Bare lymphocyte syndrome is a rare inherited primary immunodeficiency. The majority of the patients reported to date are from North Africa. We report nine new Tunisian cases., Population and Methods: Over a period of 5 years, we have established the diagnosis of bare lymphocyte syndrome in nine patients who belong to seven different families. Class II HLA antigen expression was studied on resting peripheral mononuclear cells and PHA blasts., Results: The clinical symptoms started at the mean age of 4.5 months (2-10 months) with chronic diarrhea. The evolution was characterized by appearance of other recurrent infections: pneumopathies (seven cases), thrush (seven cases), otitis (five cases) and septicemia (four cases). Allergic manifestations were observed in four cases. Six patients died at the mean age of 30 months from severe denutrition. Class II HLA antigens were not expressed on resting and activated lymphocytes. The absolute count of TCD4+ lymphocytes was decreased in seven patients. Lymphoproliferative response to specific antigens was absent. Four patients had panhypogammaglobulinemia., Conclusion: This study confirms the frequency of this disease among the North African population. The severity of the recurrent infection suggests the diagnosis of bare lymphocyte syndrome. This disease is fatal in the absence of bone marrow transplantation.

Background: Primary immunodeficiencies are rare immunopathological disorders. A multidisciplinary study group was set up in Tunis in 1988 and has since identified 152 cases of such diseases. We herein present our series and compare it to the international registries., Population and Methods: Over a period of 8 years (April 1988-April 1996), 295 children suffering from recurrent infections were investigated; primary immunodeficiency was confirmed in 152 out of them. The immunological investigation included a study of specific and/or non specific humoral and cellular immunity., Results: These 152 patients belonged to 129 families among which 70 were consanguine (54%). Familial primary immunodeficiency occurred in 23 of them. In 39 families (30%), one or more deaths occurred during early childhood. In more than half of the cases (89 cases), the immunological investigations revealed a cellular or combined immunodeficiency with a majority of ataxia-telangiectasia syndromes (53 cases), T cell activation immunodeficiencies (12 cases) and HLA class II deficiency (nine cases). A predominant antibody defect was observed in 35 patients with a majority of agammaglobulinemia (11 cases) and hyper-IgM syndromes (11 cases). A defect of non specific cellular immunity was found in 18 cases (11.8%) including seven cases of chronic granulomatous disease and five cases of leukocyte adhesion deficiency. Three children (1.9%) were deficient in the complement system. Deaths occurred so far in 37 patients (24.3%)., Conclusions: Primary immunodeficiencies are relatively frequent in Tunisia, probably because of the high rate of consanguinity among the general population. The distribution of the different groups of primary immunodeficiencies is characterized by high frequency of ataxia-telangiectasia and hyper-IgM syndrome and scarcity of severe combined immunodeficiencies and Wiskott-Aldrich syndrome.

An isolated alpha 2 plasmin inhibitor deficiency is reported in a 33 years old male, presenting repeated intramuscular hematomas since 5 years, spontaneously or after minor traumas. None of other family members were suffering from abnormal bleeding. Screening hemostatic examinations were normal except for a moderately shorted euglobulin lysis time (2 hours). Evaluation of fibrinolysis parameters (plasminogen, plasminogen activator inhibitor type 1, tissue plasminogen activator, fibrin and fibrinogen degradation products, alpha 2 plasmin inhibitor) showed normal values except for alpha 2 plasmin inhibitor which is markedly decreased (activity: 14%, antigen: < 5%). Familial hemostasis investigations have not been performed. This isolated alpha 2 plasmin inhibitor deficiency has been confirmed by two repeated control prelevments. Bleedings episodes were treated with antifibrinolytics agents (tranexamic acid). This case report shows the importance of the diagnostic approach in the laboratory to detect such rare hemostatic abnormalities associated with bleeding tendency.

Antiphospholipids antibodies (AAP) were investigated in plasma of 62 patients with systemic lupus erythematosus, and studied for the possible interference of the excess in factor VIIIc-Von Willebrand factor (VWF-VIIIc) complex in the detection of lupus anticoagulants (LA) by the activated partial thromboplastin time (APTT). We used four commercial reagents and noted that each one exhibited a different level of sensitivity of LA; the most sensitive one allowed the detection of 16 LA positive plasmas while the less sensitive reagent detected only 6 positives. The Elisa test for IgG and IgM AAP detection was positive in 25 out of 62 plasmas (40%). Comparison of the Von Willebrand factor antigen level and the APTT values showed a significant negative corrélation with 2 reagents (r = 0.369, p < 0.01 and r = 0.272, p < 0.05 respectively) that were also the less sensitive to LA. The interference of an excess in VWF-VIIIc complex was further studied by the addition of purified factor VIII in 3 LA positive plasmas. Our results suggests that an excess of factor VIIIc could lead to false negative LA, using certain APTT reagents. We conclude that a more accurate LA detection require: sensitive reagents, a pool of normal plasmas selected with normal factor VIII level, as well as repeated testing of blood sampling withdrawn away of an inflammatory process to avoid false negative LA detection.

Background: Rapid progression of chronic active hepatitis can occur in patients with hypogammaglobulinemia. This report describes the successful use of i.v. immunoglobulins to treat chronic hepatitis in a child with agammaglobulinemia., Case Report: A 17 month-old boy was admitted because he had suffered from recurrent infections since the age of 6 months. His family history was normal. Clinical and laboratory investigations showed hepatomegaly, agammaglobulinemia with absence of IgG, IgA, IgM and IgE, absence of beta cells, normal T cells, normal T cell proliferation and normal levels of complement, elevated ALAT (70 and 200 IU/ml) and ASAT (60 and 188 IU/ml). Liver biopsy showed typical features of chronic active hepatitis. The cause of this hepatitis (B and C virus, EBV, autoimmune markers) was not found. The patient was first given gammaglobulins (80 mg/kg) every week, subcutaneously, for 9 weeks, which did not change his transaminasemia. A second course of gamma-globulins, 400 mg/kg every 3 weeks, intravenously, for 6 months, resulted in a transient normalization of transaminases for 3 months. Definitive normalization was only obtained when the patient was given i.v. gammaglobulins (400 mg/kg/week) which gave a residual level of blood IgG of 10 g/l. This apparent cessation of hepatitis activity was confirmed by a second liver biopsy. The patient is now given i.v. gammaglobulins, twice a month, producing a residual blood IgG concentration of 5 g/l., Conclusions: The activity of this chronic hepatitis is closely correlated with the residual blood IgG concentration. Gammaglobulins could help neutralize virus extra-cellularly, although the viral origin of this hepatitis has not been-demonstrated.

Immunologic studies performed in a case of autoimmune chronic hemolytic anemia with low titer cold agglutinins (1/16) demonstrated that the cold agglutinins corresponded to monoclonal IgG with anti-Pr specificity. This antibody had a large thermal amplitude, being active at 37 degrees C. These unusual characteristics may define a distinct subset of chronic cold agglutinin disease.

The authors report five ultrasonic imaging between 13 and 32 weeks of gestation. All of them have an hydrops fetalis and an aspect of like masses located in the nuchal region. A cystic retrocervical hygroma was confirmed at autopsy examination in three cases. The diagnosis of cystic hygroma remains inaccurate in the other two cases in the lack of the radiographic and anatomical verification. A review of the literature was made up to define the diagnostic aspects of the hygroma colli, their histological aspects and the mains etiological factors.

Since vimentin intermediate filament (IF) expression in hemopoietic cells varies with the cell lineage as well as the state of differentiation of the cells, we studied the vimentin cytoskeleton by direct immunofluorescence and electron microscopy in 50 cases of acute nonlymphocytic leukemias. We found that malignant cells tend to reproduce the vimentin organization characteristic of their normal cellular counterpart. Thus, in M2 and M3 leukemias (French-American-British classification), vimentin was often reduced to a juxtanuclear bundle of filaments contrasting with the rich filamentous network expressed by M4 or M5 leukemias. In erythroblastic leukemias (M6) and megakaryoblastic leukemias, both identified by the expression of lineage-specific antigens, the absence of vimentin IFs could be correlated with the level of differentiation reached by the blasts. M1 leukemias displayed an abnormal pattern of vimentin organization with aggregated filaments giving a ring-like structure. However, no abnormality of the vimentin polypeptide could be detected by two-dimensional electrophoresis. These results show that the expression of the vimentin IF cytoskeleton may be a useful marker of differentiation in the study of leukemic cells.

We investigated, by indirect immunofluorescence, the binding of monoclonal IgM to human peripheral nerve in 25 patients with Waldenström's macroglobulinemia and peripheral neuropathy. In 10 cases (40%), an antibody activity against the myelin sheaths was demonstrated. The reactivity was mediated by the F(ab')2 fragments of the IgM. Prior delipidation of nervous tissue was needed to allow full expression of the target antigen(s). In nine cases, the IgM reacted with both peripheral and central myelin of primates, but not mouse or rabbit nervous tissue. In one case, the IgM reacted only with human peripheral nerve. The patients, whose IgM had an antibody activity to myelin antigen(s), had some distinct hematologic and neurologic features. The peripheral neuropathy always antedated the hematologic symptoms by several years. The serum level of the monoclonal IgM was low in all cases, and overt lymphoid malignancy was frequently absent. In other patients with neuropathy, the monoclonal IgM, which lacked antimyelin antibody activity, displayed either cross-idiotypic antigenic determinants or anti-intermediate filament antibody activity. These results taken together emphasize the heterogeneity of antibody activity of the monoclonal IgM from patients with Waldenström's macroglobulinemia and peripheral neuropathy.

The authors report on 19 cases of Inverted Papilloma collected over ten years at the Institut Gustave-Roussy. The Inverted Papillomas are rare tumors affecting predominantly adult males. This slow progressing tumor is usually revealed by unilateral nasal obstruction (68%). Its loco-regional extension is best appreciated by radiologic and tomodensitometric scanning. After limited surgical resection, the tumor may either recur (11 out of 19 cases) or show malignant evolution (9 out of 19 cases). Histopathologic criterias of this latter possibility are discussed. A radical surgical treatment such as paralateronasal rhinotomy may prevent the malignant transformation of this benign tumor.