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L Guillevin

Publications and source records attributed to L Guillevin.

At least 163 records · Page 9Linked to original sources
PubMed1998

Population pharmacokinetic study of amikacin administered once or twice daily to febrile, severely neutropenic adults.

Once-daily (o.d.) administration of 20 mg of amikacin per kg of body weight to neutropenic patients has been validated by clinical studies, but amikacin pharmacokinetics have been documented only for the 7.5-mg/kg twice-daily (b.i.d.) regimen in this population. In order to determine in neutropenic patients (i) the influence of the dosing regimen on the kinetics of amikacin, (ii) the linearity of kinetics of amikacin in the range of 7.5 to 20 mg/kg, and (iii) the influence of patient characteristics on the disposition of amikacin and (iv) to provide a rationale for dosing recommendations, we evaluated the population pharmacokinetics of amikacin administered to 57 febrile neutropenic adults (neutrophil count, <500/mm3) being treated for a hematological disorder and receiving amikacin at 7.5 mg/kg b.i.d. (n = 29) or 20 mg/kg o.d. (n = 28) and administered intravenously over 0.5 h. A total of 278 blood samples were obtained (1 to 14 samples per patient) during one or several administration intervals (1 to 47). Serum amikacin levels were measured by the enzyme-multiplied immunoassay technique. A mixed-effect modeling approach was used to fit a bicompartmental model to the data (NONMEM software). The influences of the dosing regimen and the demographic and biological indices on the pharmacokinetic parameters of amikacin were evaluated by the maximum-likelihood ratio test on the population model. The dosing regimen had no influence on amikacin pharmacokinetic parameters, i.e., the kinetics of amikacin were linear over the range of 7.5 to 20 mg/kg. Amikacin elimination clearance (CL) was only correlated with creatinine clearance or its covariates, namely, sex, age, body weight, and serum creatinine level. The interindividual variability of CL was 21%, while those of the central volume of distribution, the distribution clearance, and the tissue volume of distribution were 15, 30, and 25%, respectively. On the basis of the expected distribution of amikacin concentrations in this population, dosing recommendations as a function of creatinine clearance (CL[CR]) are proposed: for patients with normal renal function (CL[CR] of 80 to 130 ml/min), 20 mg/kg o.d. is recommended, whereas for patients with severe renal impairment (CL[CR], 10 to 20 ml/min), a dosage of 17 mg/kg every 48 h is recommended.

Adolescent↗
PubMed1998

Polyarteritis nodosa, microscopic polyangiitis and Churg-Strauss syndrome.

Polyarteritis nodosa (PAN), first described by Küssmaul and Maier, is a well-known form of necrotizing angiitis whose manifestations are weight loss, fever, asthenia, peripheral neuropathy, renal involvement, musculoskeletal and cutaneous manifestations, hypertension, gastrointestinal tract involvement, and cardiac failure. Recently individualized from PAN, microscopic polyangiitis (MPA) is a systemic vasculitis of small-size vessels whose clinical manifestations are very similar to those of PAN, but it is characterized by the presence of rapidly progressive glomerulonephritis (RPGN), which is nearly constant, and pulmonary involvement usually absent in PAN. Churg Strauss syndrome (CSS) is a disorder characterized by hypereosinophilia and systemic vasculitis similar to that of PAN and occurring in individuals with asthma and allergic rhinitis. Considering the etiologies of PAN, primary and secondary vasculitides can also be distinguished because PAN can be the consequence of hepatitis B virus (HBV) infection and sometimes of other etiologic agents. The prognosis of systemic vasculitides has been transformed by corticosteroids that are, except in HBV-related PAN, the basic treatment. Immunosuppressive drugs, especially cyclophophamide, have also contributed to improving the prognosis, but their precise role in the management of these vasculitides is still being elucidated.

Churg-Strauss Syndrome↗
PubMed1998

Temporal arteritis symptoms in a patient with hepatitis C virus associated type II cryoglobulinemia and small vessel vasculitis.

We describe temporal artery localization of hepatitic C virus related cryoglobulin induced vasculitis in a 66-year-old woman. The patient had features of both cryoglobulin induced vasculitis (palpable purpura, arthralgia, hypocomplementemia, no inflammatory syndrome) and temporal arteritis (recent onset of headaches, jaw claudication). In the temporal artery biopsy, the vasculitis was localized to a small adventitial artery and did not involve the superficial temporal artery. Thus temporal arteritis and jaw claudication can be signs of cryoglobulin induced vasculitis.

Aged↗
PubMed1998

Human neutrophil elastase in temporal (giant cell) arteritis: plasma and immunohistochemical studies.

OBJECTIVE: Few enzymes are able to attack the internal elastic lamina, which is destroyed in temporal arteritis (TA). Because human neutrophil elastase (HNE) is one of these, its role in the pathogenesis of TA was examined in patients undergoing temporal artery biopsy for suspected TA. METHODS: Over a 6 month period, 33 patients undergoing temporal artery biopsy were prospectively included in the study. TA was diagnosed in 15 patients; 9 of them had positive temporal artery biopsy. The other 18 patients made up the non-TA group. Nineteen healthy age matched subjects (mean age 74 +/- 9 yrs) served as controls. Levels of plasma HNE bound to alpha1-antitrypsin (pHNE-alpha1AT) were measured by ELISA. The presence of HNE in the temporal artery wall of 7 TA and 7 non-TA patients was evaluated immunohistochemically. RESULTS: Age, neutrophil counts, and erythrocyte sedimentation rates were similar in TA and non-TA patients. The mean pHNE-alpha1AT concentration in the TA group (84 +/- 20 microg/l) was significantly higher (p < 0.001) than in the non-TA group (51 +/- 26 microg/l) or in healthy controls (52 +/- 23 microg/l). The diagnostic sensitivity of pHNE-alpha1AT > 50 microg/l was 100%. Immunohistochemistry detected no HNE within the temporal artery wall of any patient. CONCLUSION: High levels of pHNE-alpha1AT were associated with TA. Our preliminary results indicate this could be a diagnostic marker for TA. Further studies are needed to confirm its reliability. Because HNE was not detected locally, no conclusions can be drawn as to its pathogenic role in TA.

Aged↗
PubMed1998

[Papillary edema and the POEMS syndrome].

POEMS syndrome is a multisystem disorder associated with plasma cell dyscrasia. Papilloedema is a feature of this syndrome with an incidence ranging from 33% to 84% in published reports. Its pathogenesis remains unclear. We present an observation that clearly demonstrates the difficulties to diagnose this affection. POEMS syndrome can be accepted as one of the various etiologies of papilloedema. Considering this observation and the recent publications, different pathological hypothesis are reviewed.

Cyclophosphamide↗
PubMed1998

Human immunodeficiency virus-related vasculitis. Clinical presentation of and therapeutic approach to eight cases.

Vasculitides occurring during the course of human immunodeficiency virus (HIV) infection are heterogeneous in their clinical presentation, time of occurrence, histological findings and etiological factors. Some of them can be directly attributed to HIV infection and their treatment might require new therapeutic approaches, such as plasma exchanges, specific antiviral agents and/or vasodilators. We report 8 cases of vasculitis associated with HIV. Five of them met the classification criteria of polyarteritis nodosa and had symptoms compatible with microscopic polyangiitis. Etiological agents were not identified. Although hepatitis B virus, hepatitis C virus (HCV) and other viruses or opportunistic agents were detected in some patients, HCV was suspected of being the etiological factor in only 1 of them. Focusing on viral and immunological features, the possible mechanisms of vasculitis development in HIV+ patients are discussed. Long-term follow-up indicates a clear benefit of regimens including antiviral agents, vasodilators and plasma exchanges. No deterioration of AIDS status was observed with this treatment and no relapse was recorded.

Adult↗
PubMed1997

Hypercalcemia may indicate Richter's syndrome: report of four cases and review.

BACKGROUND: Hypercalcemia has rarely been reported in patients with Richter's syndrome (RS). In this article, the authors report four cases with complementary pathophysiologic examinations. METHODS: Four patients with hypercalcemia that indicated RS were admitted to the study unit between 1980 and 1994 with the following diagnoses: transformation of mixed follicular lymphoma, Waldenstrom's macroglobulinemia, and chronic lymphocytic leukemia, respectively, in 3 men ages 60 to 73 years, and chronic lymphocytic leukemia in a woman 73 years of age. Radiologic and histologic features were reported. Circulating levels of parathormone-related peptide (PTHrP), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) were measured. RESULTS: Radiologic skeletal abnormalities were found in three of three cases: osteopenia twice and multifocal osteolysis once. All four patients had large cell lymphoma (LCL). Bone resorption assessed histomorphometrically was elevated in two of two cases. Serum TNF-alpha and IL-6 levels were high in three of three and one of three cases, respectively. Elevated values were also found in four patients with LCL but without hypercalcemia. The serum PTHrP level was increased in the only hypercalcemic patient tested and values were normal in the three control patients. CONCLUSIONS: Hypercalcemia arising in a patient with a low grade lymphoproliferative disorder may indicate RS. Hypercalcemia is due to increased bone resorption, which may be caused by the secretion of osteoclast-stimulating factors by the LCL invading the bone marrow. Independently, TNF-alpha and/or IL-6 were unlikely causative factors of hypercalcemia in the patients in this study; however, synergism with PTHrP was suspected in one case.

Aged↗
PubMed1997

A prospective, multicenter, randomized trial comparing steroids and pulse cyclophosphamide versus steroids and oral cyclophosphamide in the treatment of generalized Wegener's granulomatosis.

OBJECTIVE: To investigate the effectiveness and side effects of oral versus pulse cyclophosphamide (CYC) in combination with corticosteroids (CS) in the treatment of systemic Wegener's granulomatosis (WG). METHODS: Patients with newly diagnosed systemic WG were enrolled in a prospective, randomized trial. At the time of diagnosis, prior to randomization, every patient received a daily injection of methylprednisolone for 3 days, followed by daily oral prednisone (1 mg/kg/day) and a 0.7-gm/m2 pulse of CYC. Patients were then randomly assigned to receive either prednisone plus intravenous pulse CYC (group A) or prednisone plus oral CYC (group B) as first-line treatment. CYC was given for at least 1 year and was then progressively tapered and discontinued. RESULTS: Fifty patients were included in the study: 27 in group A and 23 in group B. At 6 months, 24 group A patients (88.9%) were in remission, versus 18 group B patients (78.3%). At the end of the trial, 18 group A patients (66.7%) and 13 group B patients (56.5%) were in remission. In group A, 66.7% of the patients experienced side effects, versus 69.6% in group B. Infectious side effects were significantly more frequent in group B (69.6%) than in group A (40.7%) (P < 0.05). The incidence of Pneumocystis carinii pneumonia was higher in oral CYC-treated patients (30.4%) than in pulse CYC-treated patients (11.1%). Nine group A patients (33.3%) and 10 group B patients (43.5%) died. Actuarial curves showed that relapses were significantly more frequent in group A (59.2%) than in group B (13%) (P = 0.02). CONCLUSION: Our results indicate that pulse CYC is as effective as oral CYC in achieving initial remission of WG and is associated with fewer side effects and lower mortality. However, in the long term, treatment with pulse CYC does not maintain remission or prevent relapses as well as oral CYC.

Administration, Oral↗
PubMed1997

Interaction between certain major histocompatibility complex class II and T-cell receptor V beta alleles promotes the antibody production to extractable nuclear antigen-related peptides.

Our objective was to study the interaction between major histocompatibility complex (MHC) class II and T-cell receptor (TCR) alleles in the recognition of extractable nuclear antigen-derived peptides in 32 patients with systemic lupus erythematosus and 173 of their family members. MHC genes were analyzed using sequence specific oligonucleotides, and TCR beta-chain gene polymorphism using restriction fragment-length polymorphism. One dominant peptide (as defined by enzyme-linked immunosorbent assay autoantibody reactivity) was identified in each antigen studied: peptide 1-20 in Sm-D, peptide 35-58 in U1-RNP-A, and peptide 304-324 in the Ro/SSA 60 Kd protein. None of the MHC class II and TCR beta haplotypes was directly associated with any of the autoantibodies. Twenty-six subjects had antibodies to the peptide Sm-D1-20; nine of them were DRB1*0101/DQB1*0501. Among subjects with this haplotype, the number of responders was higher (p < 0.028, p corrected, pc = 0.336) in those with the 2-25-9 TCR beta haplotype than in the remainder. Conversely, the number of DRB1*04/DQB1*0302 responders was lower (p < 0.030, pc = 0.360) among subjects with the 23-20-9 TCR beta haplotype than in those without. The odds ratios (OR) were 4.23 and 0.21, respectively. Of the 54 subjects positive for anti-U1-RNP-A 35-38, 13 were DRB1*0101/DQB1*0501 and eight DRB1*04/DQB1*0302. The percentage of responders was higher (p < 0.041, pc = 0.492, OR = 3.48) in the former group of subjects with the 2-25-9 TCR beta haplotype, and lower (p < 0.02, pc = 0.024, OR = 0.09) in the latter with the 23-20-9 TCR beta haplotype. Three of the 12 anti Ro/SSA 60Kd 304-324-positive subjects were DRB1*0101/DQB1*0501. All had the 2-25-9 TCR beta haplotype (p < 0.046, pc = 0.552, OR = 6.29) and none the 23-20-9 (p < 0.031, pc = 0.372, OR = 0.10). The same combinations of genes were associated with high/low response toward the three peptides. These data provide evidence for an interplay of the MHC class II and TCR beta alleles in the control of specific autoantibody response to well-defined nuclear Ag peptides.

Adolescent↗
PubMed1997

Haemophilus endocarditis: report of 42 cases in adults and review. Haemophilus Endocarditis Study Group.

To define the clinical, microbiological, and therapeutic characteristics of haemophilus endocarditis, we reviewed the charts of 42 adults with haemophilus endocarditis (native valve disease, 37; prosthetic valve disease, five) who were followed up between 1983 and 1995 in France. The mean duration of symptoms before diagnosis was 34 days. The causative Haemophilus species were as follows: H. parainfluenzae (26 adults), H. aphrophilus (9), H. paraphrophilus (4), and H. influenzae (3). According to the Duke criteria, 38 cases of endocarditis were definitive and four were possible. Thirty-nine patients received combination antibacterial therapy and three received therapy with a beta-lactam agent alone (mean duration, 46 days). Arterial embolism occurred in 15 patients. Cardiac surgery was indicated for 18 patients; 16 of these surgeries were performed within 3 months. Two patients died of heart failure. In conclusion, haemophilus endocarditis is rare and is mainly due to H. parainfluenzae. Although surgery is often necessary, haemophilus endocarditis has a favorable prognosis.

Adolescent↗
PubMed1997

Treatment of good-prognosis polyarteritis nodosa and Churg-Strauss syndrome: comparison of steroids and oral or pulse cyclophosphamide in 25 patients. French Cooperative Study Group for Vasculitides.

Twenty-five patients with good-prognosis polyarteritis nodosa or Churg-Strauss syndrome entered a prospective, randomized, multicentre study comparing two treatments: either oral corticosteroids and oral cyclophosphamide (CY; 2 mg/kg/day) for 1 yr (group A), or oral corticosteroids and monthly i.v. CY pulses (0.6 g/m2) (group B) for 1 yr. The objective was to determine the optimal CY regimen. Judgement criteria were the efficacy of the treatment in controlling the disease and the development of side-effects. Among the 25 patients who could be analysed, complete recovery was achieved with the experimental treatment in 9/12 patients in group A and 10/13 patients in group B. Two patients in each group relapsed after the end of therapy and were well controlled by corticosteroids or other drugs. One failure occurred in each group. The mean follow-up was 60.8 +/- 14.5 months after the beginning of the treatment. Side-effects associated with the administration of CY and steroids were noted 27 times in group A vs 14 times in group B (not significant). The oldest patient in these series (group B) died of pneumonia. No superiority in terms of efficacy could be established between the two regimens; however, the number of patients included was too small to conclude definitively. Toxic side-effects were significantly more frequent in women (P < 0.02). The high number of adverse effects leads us to recommend pulse over oral CY and an overall lowering of the doses of immunosuppression.

Adult↗
PubMed1997

The spectrum and treatment of virus-associated vasculitides.

It is admitted that viral infections can be responsible for systemic vasculitides. Viruses can be responsible for various types of vasculitis that affect vessels of different sizes. Clinical manifestations are the same as those observed in previously described vasculitides such as polyarteritis nodosa or cryoglobulinemia. When viral infection is diagnosed and considered to be responsible for vasculitis, a specific therapeutic approach must be prescribed. Treatment is based on the combination of antiviral agents and symptomatic or immunomodulating therapies. Antiviral therapy facilitates virus clearance and seroconversion to specific antibodies. In systemic vasculitides, plasma exchanges are a powerful treatment that clears circulating immune complexes. In the case of digital ischemia, vasodilators are also useful. Conversely, steroids and cytotoxic agents stimulate virus replication and favor disease chronicity and deleterious effects due to the presence of the virus. Hepatitis B virus-related polyarteritis nodosa can be cured with the combination of antiviral agents (mainly interferon alpha) and plasma exchanges. Hepatitis C virus-related cryoglobulinemia responds to interferon alpha and sometimes to plasma exchanges, but responses are usually partial and relapses occur in the majority of cases. In HIV-related vasculitides, currently available antiretroviral agents are not able to definitively eradicate the virus but their combination with plasma exchanges can cure the vasculitis. Due to common epidemiologic factors, several viruses can be present in the same patient, and determining their responsibility in the vasculitic process requires careful clinical and virologic analysis and then the selection of a specifically adapted therapeutic regimen. The therapeutic strategy applied in virus-associated vasculitides is therefore based on the etiologic investigations and the choice of a treatment is adapted to the pathogenetic mechanisms.

Humans↗
PubMed1997

Classification and management of necrotising vasculitides.

Systemic vasculitides are a heterogeneous group of diseases. Having only a partial understanding of the aetiologies and pathogenetic mechanisms of these disorders explains the difficulties encountered in classifying and treating patients. Nevertheless, some important points have been established. Classification is mainly based on the size of vessels affected and, from the polyarteritis nodosa group, microscopic polyangiitis (MPA) has been separated from classic polyarteritis nodosa (c-PAN). The latter is a rare disease which is, in a small number of cases, the consequence of hepatitis B or C virus (HBV/HCV) infection. In the other cases of c-PAN and in MPA, the aetiology is unknown as for Churg-Strauss syndrome (CSS) and Wegener's granulomatosis (WG). MPA, CSS and WG are mainly antineutrophil cytoplasmic antibodies (ANCA)-related vasculitides. ANCA play a part in the pathogenesis of diseases and are sometimes useful markers for diagnosis and follow-up. Vasculitis treatments should be chosen according to classification, aetiology, pathogenetic mechanisms, severity and predictable outcome. In virus-associated vasculitides, treatment is based on the combination of antiviral agents and symptomatic or immunomodulating therapies. HBV-related PAN and HCV-related cryoglobulinaemia respond to interferon-alpha and to plasma exchange. Responses are excellent in HBV-PAN but usually partial in HCV-cryoglobulinaemia, and relapses occur in the majority of cases. MPA, c-PAN, WG and other vasculitides respond to corticosteroids and cytotoxic agents, mainly cyclophosphamide. Treatment duration and ways of administration can vary from one disease to another. Plasma exchange is not recommended as the first-line treatment. Immunoglobulins and other immunomodulating treatments are indicated in limited cases and their indications necessitate further prospective studies.

Blood Vessels↗