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M C Machet

Publications and source records attributed to M C Machet.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Intraneural perineurioma: an unusual nerve sheath tumor].

We report a case of intraneural perineurioma, developed in the left cubital nerve, in a five-year old girl. This intraneural tumor is rare and shows a typical histologic appearance: concentric whorls of perineurial cells EMA+, PS100-, around nerve fibers. This tumor must be distinguished from extraneural or soft tissue perineurioma, also composed of perineurial cells, with distinct clinical presentation and histological appearance.

Child, Preschool↗
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↗
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↗
PubMed1998

Severe and early alteration of action potential during acute cardiac rejection in rats.

INTRODUCTION: Alteration of cardiac action potential and its adaptation to heart rate could contribute to cardiac dysfunction and arrhythmias during acute cardiac rejection. METHODS AND RESULTS: Heterotopic heart transplantation was performed in allogeneic and syngeneic rats in which the action potentials of right and left ventricles were measured at 1, 2.5, 3.3, and 5.7 Hz successively using standard microelectrode techniques and compared with nontransplanted hearts. For each frequency, we measured action potential amplitude, action potential duration, transmembrane resting potential, and Vmax. In the right ventricle, at 1 Hz in the presence of rejection (n = 40), a significant increase was observed in action potential duration at 20%, 50%, and 70% repolarization (82.5%, 75.6%, and 70.8%, respectively) and in action potential amplitude (+17.9 mV), and the resting potential was decreased (-5.3 mV). A lack of adaptation of action potential duration to the driving frequency was observed in the rejecting heart group in contrast to controls (n = 20) and nonrejecting hearts (n = 13). Similar results were observed in the left ventricle and surprisingly in the native hearts (n = 11) of recipients with allografted rejecting hearts in the abdominal position. CONCLUSION: Action potential and its adaptation to the driving frequency is considerably altered during acute rejection. A humoral factor could contribute to cardiac dysfunction.

Action Potentials↗
PubMed1998

[MALT lymphoma with parotid and gastric involvement during Gougerot-Sjögren syndrome].

Sjören syndrome favors the development of lymphoma, particularly in the salivary glands with MALT lymphomas. The differential diagnosis with benign lymphoepithelial sialadenitis can be difficult. A 78-year-old woman had an oculo-buccal sicca syndrome for 10 years and developed parotid hypertrophy. The first biopsy, performed 7 years before the present investigation had showed chronic lymphoepithelial sialadenitis. A second biopsy showed MALT lymphoma. Search for extension revealed a second gastric localization of the lymphoma. This patient had a particular immunophenotype, showing a CD5+ tumoral population frequently observed in mantel lymphomas and usually lacking in MALT lymphomas. Recently, however, another case similar to our own, has been reported in the literature. The observations raise the problem of distinguishing between mantel lymphoma and MALT lymphoma.

Aged↗
PubMed1998

[Desmoplastic recurrence of a melanoma of the female urethra].

We report a case of melanoma of the female urethra, recurring on the vulva as a desmoplastic invasive melanoma. The urethral tumor was an unclassifiable melanoma with an invasive epithelioid, and an intraepidermal atypical melanocytic component. The desmoplastic recidive was made of intersecting fascicles of spindled, moderately atypical cells, scattered over a dense collagenous matrix. Tumor cells were immunoreactive for S100 protein and vimentin, negative for HMB45. The morphological and immunophenotypic differences with the initial tumor, the absence of melanocytic dysplasia within the overlying epidermis, could lead to a misinterpretation of this lesion as a fibrous scar or a fibrohistiocytic tumor. Desmoplastic melanoma shares many homologies with acrolentiginous and mucous membrane melanoma and could occur more frequently on the genitourinary tract than it is generally assumed.

Aged↗
PubMed1998

[Myotomy for esophageal muscular hypertrophy with eosinophil infiltration of the esophagus associated with toxocariasis revealed by esophageal motor disorder].

We report the case of a 61-year-old-man with an eosinophilic esophagitis with esophageal motor disorder associated with toxocariasis. He complained of non cardiac chest pain and had eosinophilia leading to the detection of Toxocara canis infection. Pain persisted despite treatment of toxocariasis. Basal manometry was normal but ambulatory 24-hour manometry-pHmetry showed diffuse esophageal spasm. Ultrasonography showed a thickening of the esophageal musculature in the two inferior thirds of the esophagus. After failure of treatment with sodium cromoglycate steroids and esophageal dilatation, calcium antagonists were partially effective. A long esophageal myotomy was performed permiting the disappearance of symptoms. The histological examination of a side myotomy biopsy showed an eosinophilic infiltration of the esophageal muscle layer. This observation leads to discuss the possible relation between toxocariasis, the esophageal motor disorder and the eosinophilic infiltration of the esophageal muscle layer.

Eosinophilia↗
PubMed1998

[Chronic radiodermatitis after heart catheterization: the contributing role of ciprofibrate (Lipanor)?].

BACKGROUND: Radiodermatitis after cardiac catheterization procedures has been reported in only a few cases in the literature. This side effect may not however be uncommon after long or repeated endocavitary explorations. CASE REPORT: We observed a case of chronic radiodermatitis which developed after cardiac catheterization, in a patient treated with corticosteroids and ciprofibrate for lupus. The patient had undergone only one heart catheterization. A second catheterization performed when the patient had stopped ciprofibrate did not provoke new lesions. DISCUSSION: This observations would suggest that ciprofibrate could participate as a radiosensitizing factor in the development of radiodermatitis.

Cardiac Catheterization↗
PubMed1997

[Parvovirus B19 primo-infection and cold agglutinins].

INTRODUCTION: Parvovirus B19 infection is frequent. Primary infection leads to diverse skin manifestations including the recently described gloves-and-socks papulopurpura. CASE REPORT: A patient presented with a papulopurpuric eruption on the nose, hands, feet and perineum with cheilitis and high-grade fever. Parvovirus B19 serology showed characteristic IgG on the 15th day after the initial eruption demonstrating the seroconversion. Cold agglutinins were positive during the eruption and negative after regression. DISCUSSION: The gloves-and-socks papulopurpura syndrome was initially described in 1990. Since that time 20 cases have been reported. In 7 cases, primary parvovirus B19 infection was proven and viral infections were suspected in the others (measles, coxsackie B6, hepatitis B, Epstein-Barr virus). Our case evidenced here to undescribed skin manifestations and the development of cold agglutinins. The presence of cold agglutinins at eruption could explain the acral localizations observed in this syndrome.

Acrodermatitis↗
PubMed1996

Cutaneous alternariosis: role of corticosteroid-induced cutaneous fragility.

Alternaria is a very common and saprophytic fungus. Cutaneous infection is rare and about 71 cases have been described, mainly in Europe in immunocompromised hosts. We report a case of dermal alternariosis occurring in a woman treated with corticosteroids for dermatomyositis. The cutaneous lesion consisted of an erythematous and scaly plaque on the leg measuring 2 x 2 cm. Cutaneous biopsy showed hyphae and round inclusions stained with PAS and Gomori-Grocott within a polymorphous granuloma. Cultures of cutaneous biopsies grew Alternaria sp. HIV1 and HIV2 serology was negative. The patient was treated by local excision and corticosteroids were decreased. One-year follow-up showed no recurrence. Cutaneous alternariosis is an opportunistic infection. the disease has been described mainly in patients treated with systemic corticosteroids (39 cases out of the 71 reported cases) or local corticosteroids (3/71) and in patients suffering from Cushing's syndrome (7/71) but rarely in HIV-infected patients (3/71). Cutaneous fragility induced by hypercorticism is an important cofactor permitting direct inoculation from the environment.

Aged↗
PubMed1996

Detection of acute cardiac allograft rejection with high resolution electrocardiography: experimental study in rats.

BACKGROUND AND METHODS: To diagnose early acute cardiac rejection, we evaluated high-resolution electrocardiography in rats. Heterotopic heart transplantations were performed in allogeneic animals, either treated with cyclosporine or untreated, and in syngeneic animals. High-amplification electrocardiograms were recorded daily, under anesthesia, with two intra-abdominal leads. After amplification (x 5000 to 20,000), the electrocardiographic signal was acquired and analyzed with P-Clamp software. We measured the amplitude (millivolts) and duration (milliseconds) of the auriculogram (P wave) and the ventriculogram (QRS wave), the duration of auriculoventricular conduction (milliseconds; PQ interval) and the heart rate. Twenty-five grafted hearts were fully studied in recipients not treated with cyclosporine (allogeneic n = 16, syngeneic n = 9). RESULTS: In the allogeneic group, acute cardiac rejection was always accompanied by an early and progressive increase in P wave duration and PQ interval, whereas an increase in QRS duration was subsequently recorded. No significant change in P wave, PQ interval, or QRS wave duration was recorded in the syngeneic group, which showed no histologic rejection lesions. A decrease in P wave and QRS wave amplitude was recorded in both groups of animals. In the allogeneic group treated with cyclosporine (n = 21), grafted hearts were removed early (4.5 +/- 0.5 days): 10 cardiac grafts were rejected and 11 were not. An increase in P wave duration > or = 20% was associated with mild rejection in most cases. The sensitivity and specificity of this electrocardiographic sign were excellent (100%). The auricular (right and left atria) and the ventricular (right and left ventricles) tissues were evaluated histologically. In the allogeneic groups (n = 26), the histologic lesions during acute rejection were greater in the auricular myocardium than in the ventricular myocardium. Rejection in the atrial and ventricular myocardium was most often differentiated by one degree according to the Billingham classification. CONCLUSIONS: We concluded that acute cardiac rejection in rats is associated with early conduction disturbances in the atrial myocardium which can be shown by high-resolution electrocardiography.

Abdomen↗