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Lionel Galicier

Publications and source records attributed to Lionel Galicier.

15 recordsLinked to original sources

XIAP deficiency in humans causes an X-linked lymphoproliferative syndrome.

The homeostasis of the immune response requires tight regulation of the proliferation and apoptosis of activated lymphocytes. In humans, defects in immune homeostasis result in lymphoproliferation disorders including autoimmunity, haemophagocytic lymphohystiocytosis and lymphomas. The X-linked lymphoproliferative syndrome (XLP) is a rare, inherited immunodeficiency that is characterized by lymphohystiocytosis, hypogammaglobulinaemia and lymphomas, and that usually develops in response to infection with Epstein-Barr virus (EBV). Mutations in the signalling lymphocyte activation molecule (SLAM)-associated protein SAP, a signalling adaptor molecule, underlie 60% of cases of familial XLP. Here, we identify mutations in the gene that encodes the X-linked inhibitor-of-apoptosis XIAP (also termed BIRC4) in patients with XLP from three families without mutations in SAP. These mutations lead to defective expression of XIAP. We show that apoptosis of lymphocytes from XIAP-deficient patients is enhanced in response to various stimuli including the T-cell antigen receptor (TCR)-CD3 complex, the death receptor CD95 (also termed Fas or Apo-1) and the TNF-associated apoptosis-inducing ligand receptor (TRAIL-R). We also found that XIAP-deficient patients, like SAP-deficient patients, have low numbers of natural killer T-lymphocytes (NKT cells), indicating that XIAP is required for the survival and/or differentiation of NKT cells. The observation that XIAP-deficiency and SAP-deficiency are both associated with a defect in NKT cells strengthens the hypothesis that NKT cells have a key role in the immune response to EBV. Furthermore, by identifying an XLP immunodeficiency that is caused by mutations in XIAP, we show that XIAP is a potent regulator of lymphocyte homeostasis in vivo.

Adult↗

Low T cell responses to human herpesvirus 8 in patients with AIDS-related and classic Kaposi sarcoma.

BACKGROUND: Kaposi sarcoma (KS) occurs mainly in immunocompromised patients and is strongly associated with infection with human herpesvirus 8 (HHV-8; also known as "KS-associated herpesvirus"). We hypothesized that KS is linked to deficiencies in specific anti-HHV-8 T cell immunity. METHODS: We studied asymptomatic HHV-8 carriers coinfected with human immunodeficiency virus (HIV; n = 23) and patients with HIV-related or classic KS (n = 29). We used an interferon- gamma enzyme-linked immunospot assay with 56 specific peptides distributed on 6 HHV-8 proteins (glycoprotein [gp] B, gpH, gp35/37, latent nuclear antigen 1 [LANA-1], K12, and K15) to detect HHV-8-specific T cell responses. RESULTS: We found that patients with KS responded to these peptides less often and had much lower HHV-8-specific T cells counts than did asymptomatic HHV-8 carriers (P = .001 and P = .0004, respectively), regardless of CD4 T cell count or HHV-8 load. The frequency of Epstein-Barr virus-specific T cells was similar in both groups. CONCLUSIONS: Our results suggest that HIV-related and classic KS are associated with a lack of HHV-8-specific T cells. Also, we have described 8 new HHV-8 T cell epitopes in LANA-1, K12, and K15, including 2 CD4 T cell epitopes. These data provide new insight into HHV-8 cellular immunity.

AIDS-Related Opportunistic Infections↗

[Adult-onset primary hypogammaglobulinemia].

Hypogammaglobulinemia during adulthood can lead to recurrent infectious diseases, particularly pneumonia, otitis, and sinusitis, mainly due to Streptococcus pneumoniae and Haemophilus influenzae. Physicians must discriminate between primary and secondary hypogammaglobulinemia to provide appropriate treatment. Common variable immunodeficiency (CVID) is the most common cause of primary hypogammaglobulinemia diagnosed in adulthood. Clinical features include various combinations of infectious diseases, autoimmune diseases, lymphoproliferative disorders, and gastrointestinal diseases. Mutations in genes responsible for primary hypogammaglobulinemia in children are occasionally described in adults with CVID. ICOS and TACI deficiencies have recently been reported in a few CVID patients, although most cases have no proven genetic defects. The DefI cohort is recruiting adults with CVID throughout France. It will make it possible to describe the clinical, immunological, and genetic features of French patients with hypogammaglobulinemia and will help us to understand this immune deficiency better.

Adult↗

Time course of organ dysfunction in thrombotic microangiopathy patients receiving either plasma perfusion or plasma exchange.

INTRODUCTION: Few studies have investigated adults with thrombotic microangiopathy (TMA) requiring intensive care unit (ICU) admission, and the treatment remains controversial. OBJECTIVE: To describe causes, outcomes, prognostic factors, and daily organ-failure score changes in adults with TMA requiring ICU admission. DESIGN: A 3-yr single-center cohort study. PATIENTS: The patients were 36 adults with TMA admitted to a teaching-hospital medical ICU between January 2000 and June 2003. RESULTS: Of the 36 patients, 22 received plasma infusion and 15 underwent plasma exchange. All patients had anemia and thrombocytopenia at ICU admission, and 13 had neurologic impairment. Median creatinine clearance was 55.2 mL/min (interquartile range, 28.8-75.4). No patient had congenital TMA. Causative factors included microbiologically documented infection in 14 patients, allogeneic transplantation in 7 patients, and concomitant or subsequent systemic disease in 7 patients; 6 patients were human immunodeficiency virus-positive, 5 had drug-induced TMA, 2 were pregnant, and 2 had cancer. In 10 patients, no causative factors were identified. Plasma exchange was associated with a statistically significant decrease in hospital mortality (0 vs. 7 deaths; p < .001). Moreover, daily organ-failure scores were significantly lower in the plasma-exchange group from day 3 to day 9. Patients in the plasma-exchange group received a larger volume of plasma. CONCLUSION: Plasma exchange may be associated with faster resolution of organ failure and with improved survival for patients with TMA requiring ICU admission.

Adult↗

Intensive care in patients with newly diagnosed malignancies and a need for cancer chemotherapy.

OBJECTIVE: Patients with newly diagnosed cancer responsible for organ failures may require intensive care unit (ICU) admission and immediate chemotherapy. Outcomes in this population have not been studied. DESIGN: Prospective observational cohort study. SETTING: Teaching hospital. SUBJECTS: All patients admitted to the ICU, from January 1997 to June 2003, for organ failures due to newly diagnosed, untreated cancer and deemed necessary to receive immediate cancer chemotherapy. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: For the period of 6.5 yrs, 100 patients met the study criteria: 43 had acute leukemia, 37 lymphoma, and 12 solid tumors. Median Simplified Acute Physiology Score II was 39 (30-48) points, and median Logistic Organ Dysfunction score was 5 (3-7) points. Three variables were independently associated with 30-day mortality: need for vasopressor therapy (odds ratio, 6.01; 95% confidence interval, 1.86-19.4), mechanical ventilation (odds ratio, 6.36; 95% confidence interval, 1.76-22.94); and hepatic failure (odds ratio, 7.76; 95% confidence interval, 1.25-48.27). Overall survival was 60% after 30 days and 49% after 180 days. CONCLUSIONS: Mortality was chiefly dependent on the nature and number of organ failures, not on the nature or stage of the malignancy. The 30-day and 180-day survival rates indicate that, in this selected group of patients, advanced disease at cancer diagnosis should not lead to refusal of ICU admission. Moreover, administration of chemotherapy in the intensive care unit is feasible, and although the mortality rate is high, routine ICU admission of patients with newly diagnosed cancer, specific organ failure, and the need for administration of chemotherapy in the ICU deserves evaluation.

Adult↗

Common variable immunodeficiency is associated with defective functions of dendritic cells.

Common variable immunodeficiency (CVID) is characterized by hypogammaglobulinemia and defects in T-cell functions that could be primary or secondary. We addressed whether CVID is associated with impairment in the dendritic cell (DC) compartment, as DCs play a central role in the development of adaptive immunity. We demonstrate that DCs from CVID patients display severely perturbed differentiation, maturation, and function, and express markedly reduced levels of the costimulatory molecules that are critical for T-cell stimulation. Patients' DCs induced weak proliferation of allogeneic T cells and produced significantly low amounts of interleukin-12 (IL-12) upon CD40 signaling. Multiple defects in the immune system, including malfunctioning of DCs, appear to be prominent features of CVID patients. Impairment in both the innate and adaptive compartments of the immune system may thus cumulatively account for the inability of CVID patients to eradicate pathogens through conventional immune pathways, thus resulting in an increased risk for recurrent bacterial infections.

Cell Differentiation↗

Severe ADAMTS13 deficiency in adult idiopathic thrombotic microangiopathies defines a subset of patients characterized by various autoimmune manifestations, lower platelet count, and mild renal involvement.

The significance of ADAMTS13 deficiency in adult thrombotic microangiopathy (TMA) remains controversial. In an attempt to define the characteristics of adult TMA with severe ADAMTS13 deficiency, we determined 2 groups of patients on the basis of ADAMTS13 activity (undetectable or detectable). Clinical presentation, laboratory values, autoimmune manifestations, and outcome were compared between the groups. Patients were included retrospectively from 12 centers. All fulfilled the diagnosis criteria of TMA. Patients with a history of transplantation, cancer and chemotherapy, and Centers for Disease Control and Prevention (CDC) stage C human immunodeficiency virus (HIV) infection were not included. Forty-six patients were included. Thirty-one patients had an undetectable ADAMTS13 activity (<5%), and the remaining 15 patients had ADAMTS13 activity of >25%. Severe ADAMTS13 deficiency was associated with a plasmatic inhibitor in 17 cases (55%), suggesting an immune-mediated mechanism. Patients with undetectable ADAMTS13 were more frequently of Afro-Caribbean origin than patients with detectable ADAMTS13 activity (48.4% vs 13.3%, respectively; p = 0.03). As opposed to patients with detectable ADAMTS13 activity, patients with severe ADAMTS13 deficiency displayed various autoimmune manifestations that consisted of nondestructive polyarthritis (4 cases) associated in 1 case with malar rash and extramembranous glomerulonephritis, discoid lupus (3 cases), and autoimmune endocrinopathies, Raynaud phenomenon, and sarcoidosis-like disease (1 case each). In patients with severe ADAMTS13 deficiency, antinuclear antibodies, anti-double-stranded DNA antibodies, and anticardiolipin antibodies were positive in 22 (71%) cases, 3 (9.7%) cases, and 1 (3.2%) case, respectively. One patient fulfilled the criteria for the diagnosis of systemic lupus erythematosus. During follow-up, 1 patient with severe ADAMTS13 deficiency developed antinuclear antibodies, and 3 others developed anti-double-stranded DNA antibodies, in association with neurologic manifestations and anticardiolipin antibodies in 1 case. Patients with severe ADAMTS13 deficiency also had a lower platelet count (12 x 10(9)/L; range, 2-69 x 10(9)/L) and less severe renal failure (estimated glomerular filtration rate: 78 mL/min; range, 9-157 mL/min) than patients with detectable ADAMTS13 activity (49.5 x 10(9)/L; range, 6-103 x 10(9)/L; p = 0.0004, and 15.8 mL/min; range, 5.6-80 mL/min; p < 0.0001, respectively). End-stage renal failure occurred in 1 patient with severe ADAMTS13 deficiency and in 3 patients with detectable ADAMTS13 activity (3.2% vs 21.4%, respectively; p = 0.08). Flare-up and relapse episodes and survival were comparable between the groups. Taken together, these data indicate that adult idiopathic thrombotic thrombocytopenic purpura, as defined by severe ADAMTS13 deficiency, may occur preferentially in a particular ethnic group, and is characterized by severe thrombocytopenia, mild renal involvement, and a wide spectrum of autoimmune manifestations that may be completed during follow-up. Indeed, apparently idiopathic thrombotic thrombocytopenic purpura may be considered a specific autoimmune disease.

ADAM Proteins↗

Autoimmune thrombocytopenic purpura and common variable immunodeficiency: analysis of 21 cases and review of the literature.

To describe the main characteristics and outcome of autoimmune thrombocytopenic purpura (AITP) in patients with common variable immunodeficiency (CVID), we analyzed data from 21 patients and reviewed additional cases from the literature. To be included in this study, patients had to have CVID and a previous history of AITP with a platelet count < or = 50 x 10(9)/L at onset. A complete response to treatment was defined by a platelet count > or = 150 x 10(9)/L, and a partial response by a platelet count >>50 x 10(9)/L with an increase of at least twofold the initial level. The median platelet count at AITP diagnosis was 20 x 10(9)/L (range, 2-50 x 10(9)/L). The median age at AITP diagnosis was 23 years (range, 1-51 yr), whereas the median age at CVID diagnosis was 27 years (range, 10-74 yr). CVID was diagnosed before the onset of AITP in only 4 patients (19%), 3 of whom were being treated with intravenous immunoglobulin (i.v.Ig) replacement therapy. CVID was diagnosed more than 6 months after AITP in 13 cases (62%), and the 2 conditions were diagnosed concomitantly in 4 cases. Eleven patients (52%) had at least 1 autoimmune manifestation other than AITP, among which autoimmune hemolytic anemia (7 cases) and autoimmune neutropenia (5 cases) were preeminent. Seventeen of the 21 patients (80%) received at least 1 treatment for AITP; 13 patients received corticosteroids alone and 7 (54%) achieved at least a partial response; 8 patients received i.v.Ig at 1-2 g/kg alone or in combination with steroids, leading to a short-term response rate of 50%. Four patients underwent a splenectomy (2 complete responses, 2 failures); 2 additional splenectomies were performed for associated autoimmune hemolytic anemia. With a mean follow-up of 5.6 years after the surgical procedure, none of the 6 splenectomized patients had a life-threatening infection. With a median follow-up after AITP onset of 12 years, 13/21 patients (62%) were in treatment-free remission (7 complete responses, 6 partial responses), 7 patients (23%) were in remission while on prednisone < or = 20 mg/day with or without azathioprine, and only 1 patient still had a platelet count <50 x 10(9)/L. Five patients had died at the time of the analysis; none of the deaths was related to a hemorrhage. Severe infections including 3 fatal bacterial infections and 2 opportunistic infections occurred in 6 patients during or after treatment of AITP. In conclusion, AITP, alone or in combination with autoimmune hemolytic anemia (Evans syndrome) and/or autoimmune neutropenia, is frequent in patients with CVID, and is not prevented by i.v.Ig substitutive therapy. Since AITP frequently precedes the diagnosis of CVID, testing for immunoglobulin levels should be performed in every patient diagnosed with AITP. Steroids and splenectomy seem to have the same efficacy as in idiopathic AITP, but the increased risk of severe infections must be taken into consideration.

Adolescent↗

Herpes simplex virus type 2 as a cause of severe meningitis in immunocompromised adults.

We reviewed the clinical and demographic characteristics and outcomes for 13 immunocompromised patients with herpes simplex virus (HSV)-induced meningitis. Eleven patients were receiving chemotherapy for leukemia or lymphoma, and 10 had acquired immunodeficiency syndrome. Patients presented with acute febrile meningitis. The median white blood cell count at the onset of symptoms was 400 cells/mm3. Examination of cerebrospinal fluid (CSF) specimens showed lymphocytic meningitis, but activated lymphocytes and low glucose levels were both noted in 7 patients. HSV DNA was detected in all CSF specimens, and HSV type 2 was identified in 7. Eight patients had suspected HSV-associated mucocutaneous lesions at the time of meningitis onset. Six patients had initial radiculalgia, with sphincter involvement in 2. Eleven patients received intravenous antiviral therapy, but treatment was delayed for 6 patients. Two of the 6 patients for whom treatment was delayed developed encephalitis and died, whereas 2 others experienced persistent neurological symptoms. HSV-2 can cause severe meningitis in immunocompromised patients. Early recognition and treatment might improve the outcome of such infections.

Adult↗

Infectious diseases as a trigger in thrombotic microangiopathies in intensive care unit (ICU) patients?

OBJECTIVE: Thrombotic microangiopathy (TMA) has been associated with a large number of underlying diseases. We conducted a descriptive, retrospective study including all TMA adult patients admitted to our ICU, with a particular interest in infectious episodes as a trigger of TMA. PATIENTS: All adult patients (30) with a diagnosis of TMA admitted to the medical ICU at Saint-Louis Hospital (Paris, France) between 1992 and 1998 were retrospectively included. METHODS: All patients with clinical and microbiological evidence of bacterial infection were treated with intravenous antibiotics. The specific treatment of TMA consisted in solvent/detergent-treated plasma administration by plasma exchange or high volume plasma infusion (30 ml/kg per day) in fractionated doses. RESULTS: Among the 30 adult patients studied, TMA in 16 (53%) was associated with microbiologically documented infection. An acute infection was found in 8/9 patients with an HIV-related TMA, in 2/6 patients with a systemic lupus erythematosus (SLE)-related TMA and in 3/6 patients with TMA associated with other disorders. In three patients, an acute infectious disease was the only cause associated with the TMA. Four other patients had clinical manifestations suggesting an infection process but without bacteriological documentation. Escherichia coli was isolated in 7/16 cases and verotoxin was found in the stools of two other patients. All patients were treated with plasma administration and those with evidence of infection were systematically and intensively treated with antibiotics. Eventually 8 patients died (27%), 20 (67%) reached complete remission and 2 partial remission. CONCLUSION: Bacterial infections are commonly observed amongst TMA patients hospitalized in ICUs and may act as a trigger of this disease. Screening for infection is a requirement in patients with TMA, either idiopathic or associated with other conditions.

Adult↗

Improved survival in HIV-related Hodgkin's lymphoma since the introduction of highly active antiretroviral therapy.

OBJECTIVE: To evaluate the evolving characteristics of HIV-related Hodgkin's lymphoma (HL) and survival of affected patients since the introduction of highly active antiretroviral therapy (HAART). DESIGN AND METHODS: A retrospective single-institution study was performed over a 15-year follow-up period. For statistical analysis, patients were categorized into a pre-HAART period (1987-1996, n = 61) and a post-HAART period (1997-2001, n = 47). RESULTS: HL characteristics were similar in both groups. The chemotherapy regimens used did not differ significantly, although the MOPP/ABV regimen (mechlorethamine, vincristine, procarbazine substituted by cyclophosphamide since 2000, and prednisone /adriamycin, bleomycin, vinblastin) has progressively replaced the ABVD regimen (adriamycin, bleomycin, vinblastin, dacarbazine). A slight increase in the complete response rate was noted in the post-HAART population (74.5%) versus the pre-HAART population (64.5%), and the probability to relapse was not different between the two groups. Patients diagnosed since 1997 had a higher probability for prolonged survival with a median survival time not reached versus 19 months in the pre-HAART period. The estimate 2-year survival probability was 45% [95% confidence interval (CI), 32.3-57.8% in the pre-HAART period, and 62% (95% CI, 46.7-77.1%) in the post-HAART period ( P= 0.03). This decreased mortality was associated with a decrease in AIDS-associated deaths. In the post-HAART period, 12 patients were naive to any antiretroviral therapy and 31 were already on HAART at the time of HL diagnosis. Twenty of them had a plasma HIV-RNA below 500 copies/ml. The response rate and the overall survival were not statistically different in these patients. CONCLUSIONS: HL still occurs in patients with HAART-induced HIV suppression. However, overall survival has significantly improved since the introduction of HAART.

Adult↗

High-dose plasma infusion versus plasma exchange as early treatment of thrombotic thrombocytopenic purpura/hemolytic-uremic syndrome.

Thrombotic thrombocytopenic purpura and adult hemolytic-uremic syndrome (TTP/HUS) have a substantial mortality rate even with currently available treatments. Although therapeutic plasma exchange is the recommended treatment of TTP/HUS, this cumbersome procedure may not be available for all patients in an emergency. In this context, plasma infusion may represent an alternative first-line therapy. We compared the effectiveness of high-dose plasma infusion (25-30 mL/kg per day) and therapeutic plasma exchange as first-line treatment of adult TTP/HUS at a single center. Two groups of patients with TTP/HUS were identified according to their initial therapy, that is, high-dose plasma infusion (19 patients) and therapeutic plasma exchange (18 patients). Clinical charts and outcomes were retrospectively analyzed. Endpoints for comparison were the duration of platelet counts below 150 x 10 /L and LDH levels above normal values; the volumes of plasma administered and the duration of treatment; complete remission, relapse, and mortality rates; and treatment-related complications. Patients of the 2 groups had comparable clinical and laboratory features on admission. Sixteen patients achieved complete remission in each group. Median times to recovery of platelet counts and LDH levels were comparable between the 2 groups. Eight patients in the high-dose plasma infusion (HD-PI) group were switched to therapeutic plasma exchange because of fluid overload (6 patients), persistent biologic disturbances (1 patient), or unresponsiveness to high-dose plasma infusion treatment (1 patient). This latter patient had severe TTP/HUS that remained refractory to therapeutic plasma exchange and vincristine, and rapidly died. All 7 remaining patients achieved complete remission with therapeutic plasma exchange. Four patients in the HD-PI group and 3 patients in the therapeutic plasma exchange (TPE) group died. In the HD-PI group, 5 patients experienced a transient nephrotic-range proteinuria during treatment. Main complications in the TPE group were collapse (1 patient) and central venous catheter infection (2 patients) or thrombosis (1 patient). Three patients in each group relapsed. High-dose plasma infusion may be an efficient treatment of TTP/HUS in patients who cannot have early plasma exchange. However, the large volumes of plasma required to reach complete remission may result in fluid overload, which may necessitate subsequent therapeutic plasma exchange.

Adult↗

Systemic non-Hodgkin lymphoma in HIV-infected patients with effective suppression of HIV replication: persistent occurrence but improved survival.

The incidence of systemic non-Hodgkin lymphoma (NHL) has only slightly decreased since the introduction of highly active antiretroviral therapy (HAART), suggesting that current antiretroviral strategies do not eliminate the lymphoma risk. This study evaluates the evolving characteristics of HIV and NHL between the pre-HAART and the post-HAART periods in 246 HIV-infected NHL patients from a single institution. Major HIV-related characteristics were similar in the two periods. Most patients in the post-HAART period presented with unknown (23%), untreated (16%), or uncontrolled (37%) HIV infection. Despite an increased frequency of advanced stage IV disease in the post-HAART period (68% vs. 53%, p =.03), the overall survival has improved, with a 2-year survival probability of 61.6% versus 35.9%, (p <.001). This was associated with an increased complete remission rate (69% vs. 55%, p =.04) and the generalization of more intensive chemotherapy regimens. Most patients (76%) who developed NHL in the post-HAART period had uncontrolled HIV replication. However, 27 patients (24%) developed NHL despite an effective viral suppression at NHL diagnosis. Patients who were naive to any antiretroviral therapy at NHL diagnosis had an overall survival probability very similar to that of patients with controlled HIV replication. Improvement in the overall survival rate in the post-HAART period was associated with more intensive chemotherapy regimens, increased complete remission rate, and a likely benefit of continuation or introduction of HAART.

Adult↗

High incidence of Kaposi sarcoma-associated herpesvirus-related non-Hodgkin lymphoma in patients with HIV infection and multicentric Castleman disease.

Multicentric Castleman disease (MCD) is a distinct type of lymphoproliferative disorder associated with inflammatory symptoms and interleukin 6 (IL-6) dysregulation. In the context of human immunodeficiency virus (HIV) infection, MCD is associated with Kaposi sarcoma-associated herpesvirus, also called human herpesvirus type 8 (KSHV/HHV8). Within a prospective cohort study on 60 HIV-infected patients with MCD, and a median follow-up period of 20 months, 14 patients developed KSHV/HHV8-associated non-Hodgkin lymphoma (NHL): 3 "classic" KSHV/HHV8(+) Epstein-Barr virus-positive (EBV(+)) primary effusion lymphoma (PEL), 5 KSHV/HHV8(+) EBV(-) visceral large cell NHL with a PEL-like phenotype, and 6 plasmablastic lymphoma/leukemia (3/3 KSHV/HHV8(+) EBV(-)). The NHL incidence observed in this cohort study (101/1000 patient-years) is about 15-fold what is expected in the general HIV(+) population. MCD-associated KSHV/HHV8(+) NHL fell into 2 groups, suggesting different pathogenesis. The plasmablastic NHL likely represents the expansion of plasmablastic microlymphoma from the MCD lesion and progression toward aggressive NHL. In contrast, the PEL and PEL-like NHL may implicate a different original infected cell whose growth is promoted by the cytokine-rich environment of the MCD lesions.

Antiviral Agents↗