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L Vaillant

Publications and source records attributed to L Vaillant.

At least 91 records · Page 5Linked to original sources
PubMed1999

In vivo high-frequency ultrasonic characterization of human dermis.

The aim of this study is in vivo skin tissue characterization of young and old human cutaneous tissues by estimating the slope of the attenuation coefficient. The method used is the centroid algorithm with a second-order autoregressive model to perform the spectral analysis. Backscattered signals are acquired with a 40-MHz transducer fixed on a three-dimensional robot. Diffraction phenomena are eliminated via an axial translation of the transducer that allows the acquisition of the signal in the focal zone. The slope of the attenuation coefficient is estimated on phantoms of known attenuation, in order to validate the method. Preliminary measurements of the slope of the attenuation coefficient are subsequently performed in the echographic mode on abdominal human skin samples in vitro at 40 MHz. After assessing the reproducibility of the measurement of the attenuation coefficient slope in human dermis at 40-MHz in vivo, this is carried out on the volar face of the forearm of 150 healthy subjects aged 14-85 yr. The values measured range from 0.7 to 3.6 dB/cm.MHz. The main result of this study is the decrease with advancing age of the attenuation coefficient slope, which may reflect structural modifications of human dermis with age.

Adolescent↗
PubMed1999

Bone involvement in a case of Kaposi sarcoma.

BACKGROUND: Extracutaneous involvement is rare in the classical form of Kaposi sarcoma (KS). OBSERVATION: We report a case of bone involvement revealed by bone pain. Magnetic resonance (MR) images demonstrated the local invasion of bone from cutaneous lesions. Bone biopsy confirmed bone involvement. The patient was treated with vindesine. Bone pain progressively disappeared. CONCLUSION: Bone involvement has rarely been reported in classical KS though 4.5% of the patients were affected when it was systematically sought. Treatment of symptomatic lesions requires radiotherapy or chemotherapy.

Aged↗
PubMed1999

[Cutaneous periarteritis nodosa: diagnostic and therapeutic aspects of 9 cases].

BACKGROUND: Cutaneous periarteritis nodosa (PAN) is distinguished from systemic PAN by the lack of visceral involvement. The aim of this study was to describe the clinical presentation, laboratory findings, clinical course, and treatment in cutaneous PAN. PATIENTS AND METHODS: We retrospectively reviewed the files of patients hospitalized for vasculitis in our Dermatology unit where approximately 20 cases of vasculitis are seen each year. Inclusion criteria were skin signs suggestive of PAN and a histological image of leukocytoclastic vasculitis of an arteriole. RESULTS: Nine cases of cutaneous PAN were treated in our unit between 1976 and 1997. Follow-up ranged from 32 months to 22 years. No cases of systemic PAN had been diagnosed during this period. These 9 cases of cutaneous PAN all had the same clinical presentation: nodules on the lower limbs in all cases associated with nodules on the upper limbs in half of the cases. Neuropathy was found in 3 of the 9 cases. No systemic involvement was observed. The most frequently used treatment protocol was general corticosteroid therapy (0.5 mg/kg/d prednisone or prednisolone). Immunosuppressive drugs, colchicine, dapsone, non-steroidal anti-inflammatory drugs and intravenous immunoglobulins were also used with efficacy. DISCUSSION: Cutaneous PAN is a particular form of vasculitis associating skin signs with locoregional neuromuscular involvement. The differential diagnosis with other types of vasculitis is sometimes a difficult task. The clinical course is the fundamental diagnostic clue in cutaneous PAN. A benign course and the absence of visceral involvement allow initiating a symptomatic treatment such as colchicine. The development of neuromuscular signs may warrant the use of general corticosteroid therapy.

Adrenal Cortex Hormones↗
PubMed1999

[D-penicillamine-induced pemphigus, polymyositis and myasthenia].

BACKGROUND: D-penicillamine can induce autoimmune disease, particularly in patients with associated immune disorders. CASE REPORT: A 67-year old woman who had been taking D-penicillamine for 15 months for rheumatoid arthritis was hospitalized due to the development of a bullous eruption and proximal muscle deficiency. Search for intercellular antisubstance antibodies in serum was negative. The skin biopsy histology revealed intra-epidermal cleavage in the mucosal body and direct immunofluorescence revealed epidermal frame-marking with anti-IgG and anti-C3 antibodies. Other tests revealed muscular cytolysis, and anti-acetylcholine receptor antibodies. The electromyogram showed neuromuscular block without muscle deficiency and muscle biopsy showed moderate myositis. D-penicillamine was interrupted and was followed by cure of the pemphigus and aggravation of the myositis, requiring high-dose systemic corticosteroid therapy. DISCUSSION: This patient developed D-penicillamine induced pemphigus, a rather frequent observation. The desmoglein immunolabelling favored drug-induced pemphigus and the course was rapidly favorable after withdrawal. Pemphigus had developed simultaneously with signs of myasthenia and polymyositis. Polymyositis and myasthenia are also known complications of D-penicillamine therapy. The association of these three complications suggests that D-penicillamine can unmask certain antigens or have an immunomodulator effect.

Aged↗
PubMed1999

[Pilotropic T-cell lymphoma without mucinosis: 5 new cases].

BACKGROUND: Pilotropic cutaneous T-cell lymphomas without mucinosis are rare, with 27 cases previously reported. Diagnosis and classification may be difficult. The clinical course and histopathological and immunohistochemical findings in 5 patients are described. PATIENTS AND METHODS: Patients were selected from the register of the French Study Group for cutaneous lymphomas. The criteria for inclusion were clinical pilofollicular manifestations and histological features of pilotropic T-cell lymphoma without mucinosis. RESULTS: Five patients were selected. The most frequent clinical manifestations were follicular keratosis, alopecia and follicular papules. Typical lesions of mycosis fongoides were present for several years in 3 patients, and lymphomatoid papulosis preexisted in one patient. Histopathological analysis showed an infiltrate composed of CD3+ and CD4+ atypical lymphocytes involving the follicular epithelium with alteration of the hair follicle walls. Epidermotropism was associated with pilotropism and situated near the follicular lesions or farther apart. Alcian blue stains results were negative in all specimens. PCR studies showed the presence of a T-cell clone in the skin lesions in all cases. COMMENTS: Diagnosis of pilotropic cutaneous T cell lymphomas without mucinosis may be difficult in case of discrete epidermotropism, minimal infiltrate or involvement of the follicular epithelium. Pilotropism could define a particular variant of T-cell lymphomas.

Adult↗
PubMed1999

Short-term cyclosporin monotherapy for chronic severe plaque-type psoriasis.

Cyclosporin is an effective treatment for psoriasis but its efficacy is only palliative. The aim of this study was to evaluate the percentage of patients in whom a short term therapy may be used without relapse after discontinuation of cyclosporin. In this multicenter, open, non-controlled study fifty-eight patients were included who had severe and extensive chronic plaque-type psoriasis. Treatment duration was 28 weeks. The absence of relapse was defined as the requirement to resume systemic treatment at 16 weeks after discontinuation of Sandimmun . The overall efficacy of Sandimmun at W20 was 72%. No relapse or premature withdrawal occurred in 18 cases out of 39 (47%). In these cases local treatment was sufficient following discontinuation. Thus we show the potential value of a single 5 month course of cyclosporin treatment. In this study tapering of cyclosporin was not useful. In 50% of cases short-term cyclosporin treatment was not followed by resumption of systemic treatment and constitutes an improvement in qualify of life.

Adult↗
PubMed1999

[Bullous autoimmune diseases of the oral mucosa].

Autoimmune bullous diseases (AIBD) are characterized by autoantibodies targeted against adhesion molecules, impairing their formation. According to localization criteria, pemphigus (intraepidermal blister and desmosomal involvement) and pemphigoid (subepidermal blister and dermoepidermal junction involvement) can be distinguished. In two-thirds of the cases, pemphigus vulgaris begins with oral lesions (mainly the buccal mucosa and palate, rarely the gingiva). Skin lesions are usual. Excepting paraneoplastic pemphigus (a recently individualized entity), oral lesions are uncommon in other types of pemphigus. Cicatricial pemphigoid mainly involves oral mucosa, frequently other mucous membranes, and rarely the skin. Gingival involvement is frequent. In case of desquamative gingivitis, the clip sign gives the diagnosis of cicatricial pemphigoid. Ocular involvement is frequent and causes blindness. Epidermolysis bullosa acquisita and IgA linear dermatosis are rare. Bullous pemphigoid and bullous lupus rarely involve the oral mucosa. Diagnosis of AIBD requires a biopsy within the mucosal membrane lesion for pathology examination and another biopsy in a lesion-free area for direct immunofluorescence detection of antibody fixation. Immunoelectron microscopy or immunoblast transfer may be needed for positive diagnosis. Corticosteroids are used to treat pemphigus and dapsone is used for cicatricial pemphigoid. Immunosuppressive therapy is rarely needed.

Autoantibodies↗
PubMed1999

[Neonatal skin].

Explore the source record for details and available documents.

Adult↗
PubMed1998

Randomised comparison of thalidomide versus placebo in toxic epidermal necrolysis.

BACKGROUND: Toxic epidermal necrolysis (TEN) is associated with a 30% death rate. Tumour necrosis factor alpha (TNF-alpha) has been implicated in the pathogenesis of TEN. Thalidomide is a potent inhibitor of TNF-alpha action. We did a double-blind, randomised, placebo-controlled study of thalidomide in TEN. METHODS: The patients received a 5-day course of thalidomide 400 mg daily or placebo. The main endpoint was the progression of skin detachment after day 7. Secondary endpoints were the severity of the disease, evaluated with the simplified acute physiology score (SAPS), and the mortality. TNF-alpha and interleukin 6 were measured. FINDINGS: The study was stopped because there was excess mortality in the thalidomide group--ten of 12 patients died compared with three of ten in the placebo group (Fisher's exact test with Katz's approximation, relative risk=2.78, p=0.03). After adjustment for SAPS, mortality remained significantly higher in the thalidomide group than in the placebo group (exact logistic regression mid-p=0.007; 95% CI for odds ratio 2.7 to infinity). Plasma TNF-alpha concentration was higher in the thalidomide group than the placebo group on day 2, though the difference was not significant (Wilcoxon rank-sum test p=0.07). INTERPRETATION: Even though few patients were included, our data suggest that thalidomide is detrimental in TEN, possibly because of a paradoxical enhancement of TNF-alpha production.

Adult↗
PubMed1998

Evaluation of clinical criteria for diagnosis of bullous pemphigoid. French Bullous Study Group.

OBJECTIVE: To check the potential usefulness of clinical criteria for the diagnosis of bullous pemphigoid when state-of-the-art techniques such as Western immunoblotting, immunoprecipitation, and indirect immunofluorescence on salt-split skin or direct immunoelectron microscopy are not available. DESIGN: Comparison of the clinical criteria between 2 groups (with and without bullous pemphigoid) as defined by immunoelectron microscopy used as standard criterion, in a prospective study. Multivariate logistic regression analysis was carried out by including all items that were statistically significant (at P < .05 level) in univariate analysis. SETTING: Five dermatology departments in teaching hospitals. PATIENTS: The 231 patients studied had subepidermal autoimmune bullous diseases with linear IgG or C3 deposits in the basement membrane zone (157 with bullous pemphigoid, 33 with cicatricial pemphigoid, 30 with epidermolysis bullous acquisita, 5 with lupus erythematosus, and 6 others). A second set of patients was used to calculate predictive values. RESULTS: The multivariate logistic stepwise analysis resulted in a final set of predictors that included only 4 items: absence of atrophic scars, absence of head and neck involvement, absence of mucosal involvement, and age greater than 70 years. No additional variables met the .05 significance level to enter into the model. If 3 of these 4 characteristics were present, a diagnosis of bullous pemphigoid could be made with a sensitivity of 90% and a specificity of 83%; these predictive values were calculated on a sample of 70 new cases. CONCLUSIONS: With and estimated incidence of bullous pemphigoid among subepidermal autoimmune bullous diseases of 80%, the presence of 3 of the 4 significant criteria allows the diagnosis of bullous pemphigoid, with a positive predictive value of 95%. Our set of clinical criteria thus allows the diagnosis of bullous pemphigoid with good validity for both clinical practice and therapeutic trials.

Aged↗
PubMed1998

An in vivo method for measuring the mechanical properties of the skin using ultrasound.

In this study, we report a new and original device called the "echorheometer," comprising a suction system with an ultrasound scanner (A-mode, TM-mode and B-mode) that enables the simultaneous visualization and measurement of the deformation of skin structures in vivo. With the scanner described here, high resolution is obtained using a strongly focused, wide-band 20-MHz center frequency transducer, with an axial resolution of 0.07 mm. This device can determine, noninvasively, not only those skin structures that are involved in the deformation, but also their morphological variation and their extent of involvement with the degree of stress applied. Using this device, the behavior of the dermis and subcutaneous fat, while under suction, was investigated on the volar forearm of 10 volunteers. The results showed that the resistance to the applied vertical stress is essentially due to the dermis rather than the subcutaneous fat, and that there is a certain amount of infiltration of fluid into the tissues under suction. In addition, it was shown that the dermal response to an applied suction is initially due to its own natural tension and that, with increasing deformation, the intrinsic dermal elasticity has a greater contribution to the resistance of stress. With this information, we hope to develop a mechanical model to define appropriate mechanical parameters for skin. This will allow the evaluation of changes in the dermis and also enable therapeutic intervention to be assessed. Furthermore, it could also be applied to studies of skin ageing and the assessment of cosmetic product efficacy (emolliency, hydratation, etc.).

Adult↗
PubMed1998

Bilateral conductive deafness related to erosive lichen planus.

A case of bilateral progressive stenosis of both external auditory canals with resultant conductive hearing loss is presented. The stenosis revealed multifocal erosive and synechiant lichen planus. To our knowledge, this is the first reported case of lichen planus involvement of the external ear.

Aged↗