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L Machet

Publications and source records attributed to L Machet.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Cutaneous vasculitis, myelodysplasia and relapsing polychondritis].

BACKGROUND: Relapsing polychondritis is a rare autoimmune disease, characterized by recurrent inflammation of cartilaginous tissues. In some cases, many other tissues can be involved. CASE REPORT: We describe the case of a 64 year-old man with relapsing polychondritis, whose first symptoms were papulonodular and mucosal aphthous lesions. The skin biopsy revealed vasculitis without leukocytoclasic features. The diagnostic of relapsing polychondritis was made only two years later, thanks to recurrent auricular chondritis. Since the beginning, the disease was associated with a myelodysplasia. DISCUSSION: Dermatological manifestations are noticed in less than 50 p. 100 of cases during the evolution of relapsing polychondritis. An association with a myelodysplasia has already been reported, and it could be a particular form of relapsing polychondritis. Myelodysplasic syndromes are more frequently associated with relapsing polychondritis than with other vasculitis. It must be sought especially when cutaneous and mucosal manifestations exist.

Humans↗
PubMed2002

[Recurrent aphthous stomatitis: treatment with colchicine. An open trial of 54 cases].

INTRODUCTION: Colchicine is a treatment used for aphthous stomatitis but its efficacy has never been proved. We report the results of an open trial of 54 patients treated with colchicine for aphthous stomatitis. The aim of our study was to assess the long and short term efficacy and tolerance of this molecule in this disease. PATIENTS AND METHODS: The case reports of 64 patients presenting with severe, recurrent aphthous stomatitis treated with colchicine between 1986 and 2000 were analyzed retrospectively. Only immunocompetent patients exhibiting idiopathic aphthous stomatitis or Behçet's disease were included. Ten patients were excluded: 4 cases of Behçet's disease treated with colchicine and systemic corticosteroids, 4 cases of aphthous stomatitis secondary to a hematological cause and 2 patients who were lost to follow-up after 3 month's treatment. Colchicine was prescribed at a dose of 1 to 1.5 mg/d for at least 3 months. All the patients were assessed after 3 month's treatment and all were contacted by phone in May 2000. Our end-point criteria were: the frequency and duration of the episodes, intensity of pain and impact on the quality of life of the patients. RESULTS: Fifty-four patients were included: 39 women (mean age=44 +/- 16.8) and 15 men (mean age=49 +/- 13.5). The disease had progressed for a mean of 11.6 +/- 13.5 years. After 3 month's treatment, 12 patients (22 p. 100) no longer had aphta and were in complete remission, 22 patients (41 p. 100) were significantly improved, since the frequency and duration of the lesions had decreased by at least 50 p. 100 and the latter were no longer painful. Treatment failed or tolerance was poor in 20 patients (37 p. 100). Patients were monitored and assessed for a mean of 4.7 years (range: 6 months to 13 years). Six patients were lost to follow-up. Three patients (6 p. 100) were considered as cured, since they were still in complete remission after suspension of colchicine respectively 6, 24 and 72 months later. Fifteen patients (31 p. 100) had still improved. Among the latter, 10 continued colchicine for a mean of 27 months, and 5 patients stopped treatment, which they considered tedious, after a mean of 16 months. These 15 patients noted a significant reduction in the frequency and duration of the lesions. Moreover, the subjective end-point criteria had improved significantly for them not to wish to change treatment. Thirty patients (63 p. 100) were not improved by the treatment. Some benign adverse events were noted in 10 patients (18.5 p. 100) and led to suspension of treatment in 4 cases. DISCUSSION: This study, which is the first in size (n=54) and duration of follow-up (4.7 years), showed that colchicine is an efficient preventive treatment of severe aphthous stomatitis for 63 p. 100 of patients after 3 month's treatment and that this improvement was lasting in 37 p. 100 of them. Colchicine should therefore be proposed in first intention in severe recurrent aphthous stomatitis, since it is effective, well tolerated and easy to use.

Adult↗
PubMed2001

In vitro study of low-frequency ultrasound-enhanced transdermal transport of fentanyl and caffeine across human and hairless rat skin.

The effect of low-frequency sonophoresis on fentanyl and caffeine permeation through human and hairless rat skin was studied in vitro. Experiments were performed using 20 kHz ultrasound applied at either continuous or discontinuous mode and with an average intensity of 2.5 W/cm(2). The results showed that low-frequency ultrasound enhanced the transdermal transport of both fentanyl and caffeine across human and hairless rat skin. This was explained by both increasing flux during sonication and shortening the lag time. Discontinuous mode was found to be more effective in increasing transdermal penetration of fentanyl while transdermal transport of caffeine was enhanced by both continuous and pulsed mode. Histological and electron microscopy studies showed that human and hairless rat skin was unaffected by ultrasound exposure. Further studies will be necessary to determine the relative contribution of ultrasound parameters in low-frequency ultrasound-induced percutaneous enhancement of drug transport.

Administration, Cutaneous↗
PubMed2001

Clinical, histologic, and electron microscopy study of skin exposed to low-frequency ultrasound.

The use of low-frequency ultrasound has been proposed to enhance the transdermal transport of various drugs, a technique referred to as sonophoresis. The aim of the present study was to determine the safety of low-frequency sonophoresis on human and rat skin by evaluating their structural modifications after ultrasound exposure. Human skin samples and hairless rats were exposed to 20 kHz ultrasound in vitro and in vivo, respectively. Ultrasound was used with average intensities ranging from 0.25 to 7 W/cm(2) in pulsed or continuous mode. Hairless rats were also exposed to a heat source mimicking the temperature versus time profile during sonication. Skin samples were observed under optical and electron microscopy to detect any structural changes. Human skin samples exposed to intensities lower than 2.5 W/cm(2) showed no modification. For hairless rats, slight and transient erythema was observed after 2.5 W/cm(2) exposure, whereas deep lesions (dermal and muscle necrosis) were observed 24 hr later. These lesions were also observed when a plastic film was placed between the coupling medium and the animals' skin during sonication. In contrast, no histologic lesion could be seen when a heat source was applied to animal skin. Low-frequency ultrasound induces delayed and deep lesions in hairless rat skin at 2.5 W/cm(2) which are not only attributable to the increase in temperature at the skin surface during ultrasound exposure. By using the same ultrasound conditions, human skin seems to be less sensitive in vitro.

Animals↗
PubMed2001

[Fatal toxic respiratory epitheliolysis. Subacute tracheo-bronchial desquamation in Stevens-Johnson syndrome].

Acute bronchial mucosal sloughing related to Toxic Epidermal Necrolysis (Lyell syndrome) is widely reported in literature. On the contrary severe respiratory involvement is rare in post-infectious or toxic Epitheliolysis (Stevens-Johnson syndrome). There is no well-known predictive sign of bronchial epithelium involvement. An 18-year-old patient was admitted for Stevens-Johnson syndrome related to sulfasalazine (salazosulfapyridine). There were no respiratory signs. An acute respiratory failure occurred 36 hours after from admission due to an obstructive and desquamative necrosis of the tracheobronchial epithelium. We purpose that a fiberoptic laryngoscopy should be performed even in non-dyspneic patients suffering from Stevens-Johnson syndrome if hypersecretion is present. Fiberoptic bronchoscopy can be helpful in these cases.

Acute Disease↗
PubMed2001

[Radiation-induced skin toxicities: prevention, treatment].

Acute and long term effects are frequent after radiotherapy. They may alter the general status and quality of life of the patients. Chronic radiodermatitis may result in ulceration and in transformation into a squamous cell carcinoma. There is a correlation of the frequency of acute dermatitis with the total dose. Chronic radiodermatitis may develop after repeated small doses of ionizing radiation for cardiac catheterization and coronary angioplasties. The other prognostic factors for the level of acute and late skin reactions are volume of tissue treated, total daily dose, fractionactions schemes ... but there are some variation in the degree of reaction in patients treated with identical radiotherapy schedules. There is a patient-to-patient variability. Several diseases as systemic sclerosis, some genetic diseases, perhaps some drugs may increase the cutaneous reactions. So both acute and chronic irradiation injury is a complex process with many regulations. Chronic fibrosis may be caused by mechanism of cell activation (and particularly fibroblasts). Cytokines e.g. transforming growth factor beta (TGF-beta) might be involved in the induction of fibrosis. Treatment use emollients. Superoxide dismutase was used as an ointment for radiofibrosis therapy and obtains a reduction of the fibrosis. In late phases plastic surgery or sometimes cryosurgery can be used.

Administration, Topical↗
PubMed2000

Delays in diagnosis and melanoma prognosis (II): the role of doctors.

A prospective survey was conducted to assess physician responsibility in melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a standardized questionnaire. Main outcome measures were medical components of the delay before tumor resection and tumor thickness. Of 590 melanomas, 29.1% were coincidentally detected by physicians and their tumor depth was lower than in melanomas detected by patients (p < 0.001). Physician sensitivity for melanoma diagnosis was evaluated at 86%. Median time intervals to propose resection and to perform removal of melanoma were short: 0 (mean 103) and 7 (mean 68) days, respectively. Melanomas were managed in an inappropriate way in 14.2% of cases. Location on acral areas and absence of pigmentation were associated with longer medical delays and more frequent inappropriate medical attitudes. Melanomas located on hardly visible areas were less frequently detected by physicians than those on visible areas. Medical delays were shorter, doctor's attitude was more frequently appropriate, and melanoma thickness was lower (p < 0.001) when the patient visited a dermatologist (54.7%) than when he or she visited a general practitioner (33.4%). Our study shows that doctor responsibility accounts for only a small part of the total delay before melanoma removal. However, systematic total examination and better training of doctors, especially about unusual forms of melanoma, could still improve melanoma detection.

Attitude of Health Personnel↗
PubMed2000

Delays in diagnosis and melanoma prognosis (I): the role of patients.

A prospective survey was conducted to assess the role of patients in the melanoma prognosis. Consecutive patients with primary melanoma were interviewed and examined using a comprehensive questionnaire including a psychological instrument. Main outcome measures were the delay before medical intervention and the tumor thickness. Of 590 melanomas, 70.8% were detected by patients and this proportion was higher in females. Relatives were involved in the detection of half of the cases. Median delays before the patient realized he had a suspicious lesion, before this lesion was seen by a doctor, and before the melanoma was removed were 4 months, 2 months, and 1 week, respectively. Delays up to several years were observed in some cases. The rate of self-detection tended to be lower, the delays before seeking medical advice to be longer, and the tumor thickness to be higher in old people, in males, in lower-educated individuals, in those living out of towns, and in people with a low awareness about melanocytic tumors than in other cases. Conversely, individuals with a high number of atypical nevi, those who were aware to be at risk, and those who regularly visited a dermatologist tended to detect their melanoma more rapidly. No specific psychological traits were associated with a late reaction, although negligence and anxiety tended to prolong the delays. Knowledge about melanoma was poor in many patients, especially in males, and wrong beliefs were widespread. This study provides the targets of future education programs.

Adolescent↗