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Olivier Dereure

Publications and source records attributed to Olivier Dereure.

17 recordsLinked to original sources
PubMed2004

Panniculitis due to non-tuberculous mycobacteria in two immunocompromised patients.

Inflammation of subcutaneous tissue (panniculitis) may occur in association with tuberculosis, but so far only three cases of non-tuberculous mycobacteria-related lobular panniculitis have been reported. We describe two new cases with marked cellular immunity failure due to hypercorticism. Clinical presentation did not differ significantly from lobular panniculitis of other aetiologies. Histological samples displayed signs of lobular panniculitis and clues for mycobacteria infection with granulomatous lesions and presence of numerous acid-fast bacilli on special staining. Both patients responded quickly to a combination of macrolides, ethambutol and fluoroquinolones. However, like in other infections with tuberculous or non-tuberculous mycobacteria, long-term treatment (at least 6 months) was necessary to prevent relapses.

Aged↗
PubMed2004

Cutaneous malignant melanoma and neurofibromatosis type 1.

Neurofibromatosis 1 (NF1) is a genetically transmitted disease occurring approximately once in 3000 live births and resulting from mutations of the NF1 gene that encodes a protein named neurofibromin, a negative regulator of the ras-dependent pathway. An excess of neoplasia especially tumours of neuroectodermal origin is classically observed. The occurrence of malignant melanoma in patients with NF1 has already been described in scattered clinical reports but little is known as to the characteristics of melanoma arising in NF1 patients. A multicentric retrospective study was conducted on a panel of French referring centres for a period of 13 years to identify patients with both melanoma and NF1. Patients with mucosal or ocular melanoma were excluded. The diagnosis of malignant melanoma was based on specific histology whereas NF1 was identified according to the criteria proposed by the NIH Consensus Conference. All patient fulfilling criteria for both melanoma and NF1 were investigated using a common procedure recording clinical and histological data along with prognostic factors for the two diseases. Eleven patients were identified with both diseases. The clinical pattern of NF1 was quite similar to the classical form of the disease, but some unusual features were present as regards to the melanoma: a sex-ratio of 10 women for one man and an average age lower than expected (median age=33 years) for melanoma occurrence. Among prognostic factors, median thickness was high compared to large series of melanoma in the literature (3.20 versus 1.5 mm). Another neoplasia occurred in three patients. An increase in melanoma incidence in patients with NF1 remains hypothetical but our small series of malignant melanoma arising in NF1 patients displays a large female preponderance, a higher thickness than expected and a frequent association with a second neoplasia. The peculiar female proneness for cancer whatever its localization and the risk of multiple neoplasias have already been reported in NF1 patients and could be true for malignant melanoma as well.

Adult↗
PubMed2003

Improved sensitivity of T-cell clonality detection in mycosis fungoides by hand microdissection and heteroduplex analysis.

BACKGROUND: The presence of a dominant T-cell clone is an important diagnostic criterion in cutaneous T-cell lymphomas (CTCLs) and in atypical T-cell cutaneous infiltrates. Procedures based on polymerase chain reaction (PCR) are the most sensitive to detect clonality, but heteroduplex analysis is less sensitive than other methods such as denaturing gradient gel electrophoresis. OBJECTIVE: To assess whether a gross hand microdissection of the superficial (papillary) portion of the dermal infiltrate may improve the sensitivity of T-cell clonality detection by PCR-heteroduplex analysis in CTCL. SETTING: Regional university hospital (secondary or tertiary referral center). Patients A total of 29 patients with a definite diagnosis of mycosis fungoides based on typical histologic and immunophenotypic features were selected with patch (16) or plaque (13) stages. MAIN OUTCOME MEASURES: Assessment of T-cell clonality by PCR amplification of the T-cell receptor gamma chain followed by heteroduplex analysis using DNA extracted from the entire biopsy specimen and after gross microdissection of the subepidermal bandlike dermal infiltrate. RESULTS: T-cell clonality was demonstrated in 24 of 29 cases when hand microdissection was used compared with 16 of 29 cases with DNA analysis from entire biopsy specimens; thus, hand microdissection resulted in a sensitivity improvement of approximatively 50%. CONCLUSIONS: Hand microdissection substantially improves the detection of a T-cell clone in CTCL when using a PCR-heteroduplex analysis and could be used routinely in the clinical evaluation of T-cell infiltrates. Importantly, the microdissection method was found to be more useful for the detection of T-cell clones in early patch stages of CTCL than in plaque-stage disease.

Clone Cells↗
PubMed2003

Correlations between clinical, histologic, blood, and skin polymerase chain reaction outcome in patients treated for mycosis fungoides.

Little information is currently available regarding post-treatment outcome of TCR-targeted PCR in skin and/or peripheral blood in patients with Mycosis Fungoides (MF) when a dominant gene rearrangement is present at time of diagnosis. To address this matter, a study evaluating the correlations between post-treatment clinical, histological, blood and skin PCR data was conducted in MF patients. Twenty-seven MF patients with dominant gene rearrangement in skin lesions at time of diagnosis were selected. Peripheral blood samples were investigated as well before treatment and post treatment molecular data in skin and blood were compared with clinical and histological outcome. A dominant gene rearrangement was detected before treatment in blood of 16/25 patients. The dominant gene rearrangement disappeared from cutaneous lesions in 8/13 patients displaying complete clinical and histological response whereas skin PCR remained positive in all 10 patients with histologically persistent disease. A dominant gene rearrangement was still present in blood in 10/16 patients after treatment and blood data were not correlated with skin molecular response. This study confirms frequent detection of a dominant gene rearrangement in peripheral blood in MF patients and shows that PCR may remain positive in lesional sites even when skin lesions are successfully treated.

Adult↗
PubMed2002

Infrequent Fas mutations but no Bax or p53 mutations in early mycosis fungoides: a possible mechanism for the accumulation of malignant T lymphocytes in the skin.

Mycosis fungoides (MF) is the most frequent manifestation of cutaneous T cell lymphoma but its cause and pathophysiology remain unclear. Because progression of lesions is characteristically slow, we hypothesized that mycosis fungoides originates from an accumulation of lymphocytes due to defective apoptosis of skin homing T lymphocytes. In this study, we investigate possible alterations of three molecules regulating apoptosis, i.e., Fas antigen, Bax, and p53, at the genomic level in skin lesions from 44 patients with MF, as Fas mediates one of two major pathways for apoptosis of activated T cells. Fas mutations were found in six patients using a polymerase chain reaction and single-strand conformational polymorphism method followed by cloning and sequencing of abnormal polymerase chain reaction products. The mutations predict for defective transmission of the death signal in three cases. Immunohistochemistry demonstrated the lack of Fas protein expression on dermal lymphocytes in one case with Fas gene mutation predicting for a truncated death domain, whereas Fas protein was expressed by dermal lymphocytes in the other investigated cases. By contrast, no mutations of Bax or p53 were found, whereas immunohistochemistry demonstrated increased p53 expression in the nucleus of basal keratinocytes above the neoplastic infiltrate in some MF cases. These results support the hypothesis that Fas defects may play a role in the pathogenesis of MF.

Apoptosis↗
PubMedDate not supplied

Vitamin a deficiency phrynoderma associated with chronic giardiasis.

Phrynoderma is a rare form of follicular hyperkeratosis associated with deficiencies in vitamins A or C or essential fatty acids. We report a 6-year-old boy with an unusual presentation of phrynoderma, characterized by multiple minute digitate hyperkeratoses associated with hair casts and related to a severe deficiency in vitamins A and C complicating a chronic intestinal giardiasis. The lesions responded well to oral vitamins A and C combined with albendazole treatment. Vitamin A deficiency-related phrynoderma is rare in western countries and is usually caused by digestive malabsorption resulting from large intestine resection or pancreatic failure. To our knowledge, this is the first reported instance of phrynoderma related to a chronic intestinal parasitic infection by Giardia intestinalis with intestinal malabsorption as a likely consequence.

Albendazole↗
PubMedDate not supplied

Ichthyosiform mycosis fungoides.

Malignancy-associated acquired ichthyosis is well known, but the ichthyosiform subset of mycosis fungoides (MF) is rarely reported. We report on two patients with a clinical presentation for whom diagnosis of mycosis fungoides was established on histological grounds. In both cases, long term remission was obtained with non aggressive therapies. This rare condition must be added to newly described forms of MF with epidermal hyperplasia such as keratosis lichenoides chronica like MF and pilotropic MF.

Aged↗
PubMedDate not supplied

Urticaria pigmentosa localized on radiation field.

A woman previously treated by radiotherapy for a breast cancer developed urticaria pigmentosa mainly restricted to the irradiation field, without any systemic symptoms. Localized forms of urticaria pigmentosa are exceptional, and their triggering factors are poorly understood. Several hypotheses can be discussed in this peculiar observation, among which a direct role of radiotherapy in the occurrence of cutaneous lesions cannot be ruled out.

Adult↗
PubMedDate not supplied

Multiple haemorrhagic-like cutaneous metastasis of malignant melanoma.

Cutaneous metastasis of malignant melanoma usually presents as pigmented or non-pigmented, sometimes angiomatous nodules of various sizes. However, we recently observed a further example of haemorrhagic-like cutaneous metastasis, a quite infrequent clinical pattern, remarkable for the multiplicity of lesions.

Adult↗