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Pascale Quatresooz

Publications and source records attributed to Pascale Quatresooz.

At least 19 recordsLinked to original sources
PubMed2006

Spotlight on nail histomycology.

The misdiagnosis of onychomycosis delays the proper treatment of the nail condition. Nail histomycology refers to the microscopic examination of histologic sections prepared from nail clippings for the purpose of detecting the presence of fungi. This laboratory method is the most sensitive procedure for the diagnosis of onychomycosis. It allows for the visualization of the precise location of the invasive fungus inside the nail apparatus. The method also distinguishes various shapes of the fungal cells, in particular filamentous fungi, yeasts, conidia, and sporodochia. The correct diagnosis provided by histomycology combined with culture not only allows for more efficient expenditure of funds and services but also is important for the timely alleviation of the disorder.

Diagnosis, Differential↗
PubMed2006

Diffuse dermal angiomatosis: A previously undescribed pattern of immunoglobulin and complement deposits in two cases.

Two cases of diffuse dermal angiomatosis are reported in middle-aged women. This rare disease of unknown origin is characterized by increased dermal angiomatosis and ulceration. The clinical and histologic presentations of the presently reported lesions were typical for this disorder. Endothelial cells exhibited a normal immunophenotype. The perivascular basement membranes showed a distribution of collagen alpha chains typical for blood vessels, but not for lymphatics. Immunohistochemistry revealed other undescribed features. At the site of the clinical lesions, linear and granular deposits of immunoglobulins A and M, and complement were found around the vessels and at the dermal-epidermal junction. The same deposits were also found restricted to the dermal-epidermal junction in the peripheral clinically intact skin. No serological signs of auto-immune disorder were detected in one patient. A monoclonal gammopathy was disclosed in the other patient. A pattern of immunoreactant deposits similar to that disclosed in the two patients was not found in the control specimens, and has not been described so far in other types of vascular hyperplasia and neoplasia. A pathogenic role of these deposits is unsettled and should be further explored.

Abdomen↗
PubMed2006

Mechanobiology and force transduction in scars developed in darker skin types.

BACKGROUND: Scarring is a complex process involving many cell types, cytokines and biological pathways including mechanobiology. Some subtle mechanical properties of skin can be assessed by measuring the speed of ultrasound shear wave propagation. The orientation of abnormal skin tension forces can be visualized, particularly in darker skin types, using dermoscopy showing distinct patterns of rete ridges' conformation. AIM: To assess some mechanobiological features of scars in darker skin types. PATIENTS AND METHODS: Large atrophic and hypertrophic surgical scars were examined on the trunk of 35 darker skin subjects. The surrounding skin was used as a comparator. Dermoscopic aspects were recorded. Resonance running time measurements (RRTM) were performed using a shear wave propagation device (Reviscometer). They were performed in four specific directions at given angles with regard to the long axis of the scar. The minimum, maximum and mean RRTM values were recorded at each site. RESULTS: Dermoscopy revealed patterns of melanin deposits in scars distinct from the normal honeycomb network seen in the surrounding skin. Hypertrophic scars showed a patchy pattern of large macular melanoderma dispersed in a lighter background. In these cases, low RRTM values were obtained with little variations according to the orientation of the measurements. By contrast, atrophic scars showed a streaky laddering melanotic pattern under dermoscopy. Higher RRTM values were often obtained, particularly in the transversal direction of the scars. Mechanical anisotropy was greater in the atrophic scars compared with the normal skin. DISCUSSION: Darker skin types represent a model for visualizing the main orientation of the epidermal rete ridges. A correlation was found between the pattern of melanized rete ridges of scars and the main orientation of the intrinsic forces in the skin.

Adult↗
PubMed2006

Skin climacteric aging and hormone replacement therapy.

A gender perspective is indispensable for a full understanding of aging. Menopause is a turning point in women's lives. In addition to the effects of chronological aging, sunlight exposure, and other environmental and endogenous stimuli, the climacteric appears to exert some dramatic consequences on skin biology and aspect. The epidermis may become xerotic and exhibit altered functions. The dermis thins out and its elasticity decreases in concert with the decline in bone mass. The skin microcirculation is impaired. These aspects are some of the better worked-out changes of the climacteric, which in turn seem to be stabilized or in part reversible with hormone replacement therapy (HRT). The HRT effect on menopause consequences on hair growth and sebum production is less impressive. This review summarizes some important impacts of the climacteric on skin, and highlights the benefits of HRT that may influence cosmetic dermatology.

Biomechanical Phenomena↗
PubMed2006

Blood vessel changes during pregnancy: a review.

The profound endocrine upheaval of pregnancy is frequently associated with changes in the function and structure of the blood and lymph microvasculature of the skin and mucosae. Palmar erythema is frequent but rarely severe and is associated with burning sensations. Spider telangiectasias develop in the majority of pregnant White women but are less often identified in women with darker skin. Hemangiomas and glomus tumors occur in one-third of women. A firm edema may develop on the face and extremities in the final months of pregnancy. Venous hypertension and varicosities of the lower limbs are common. Gingivitis, gum hypertrophy, and pyogenic granuloma are common in the oral cavity. The vaginal mucosa is also affected, showing a violaceous aspect, at times accompanied by varicosities of the vulva. Many gestational vascular changes regress spontaneously in the postpartum phase. Some vascular tumors may need to be treated with a vascular laser or intense pulsed light.

Blood Vessels↗
PubMed2005

Novel treatments for drug-induced toxic epidermal necrolysis (Lyell's syndrome).

Drug-induced toxic epidermal necrolysis (TEN) is a life-threatening disease characterized by extensive destruction of the epidermis. It apparently results from the formation of specific toxic drug metabolites by the keratinocytes. The mortality rate which averages 25-30% is mainly due to secondary septicemia, and to ionic and metabolic disturbances following loss of epidermal integrity. Apoptosis is the likely mechanism leading to massive keratinocyte death in TEN. Dysregulations in the tumor necrosis factor-alpha (TNF-alpha) pathway, CD95 system (Fas ligand, CD95L; Fas receptor, CD95R) and calcium homeostasis in the epidermis are involved in this apoptotic process. An active role has also been ascribed to T lymphocytes, macrophages and factor XIIIa-positive dermal dendrocytes. Despite progress, treatment of TEN remains controversial. In the past, systemic glucocorticoids were used in order to target the inflammatory reaction in TEN. However, there was no evidence for improvement of the healing process, while corticosteroids worsened the prognosis by increasing the risk of septicemia. Only a few cases have been treated with other drugs including cyclophosphamide, pentoxyfilline, thalidomide, anti-TNF-alpha antibodies and cyclosporin A. In the recent past, some TEN patients were treated with intravenous human immunoglobulins (IVIG). The rationale for such a treatment was to block the CD95 system on keratinocytes. The early promising clinical results of IVIG treatment in TEN were subsequently challenged. This review compares the effectiveness and drawbacks of the major drugs presently used in TEN treatment. Some future prospects in TEN management are also discussed.

Apoptosis↗
PubMed2005

Immunohistochemical detection of incipient melanoma micrometastases. Relationship with sentinel lymph node involvement.

It is acknowledged that tumour thickness, ulceration and lymph node invasion are the most important prognostic factors for cutaneous melanomas. Other histopathological features may also be informative. The aim of this study was to ascertain whether immunohistochemical methods can improve the detection of satellite micrometastases in primary melanoma patients. In addition, the predictive value of cutaneous satellite micrometastases for sentinel lymph node involvement was evaluated. A total of 265 primary cutaneous melanomas and 68 of the respective sentinel nodes were studied using a panel of seven antibodies directed against melanocyte-related antigens. In 12.4% of the 265 cases, small satellite micrometastases were detected by immunohistochemistry. Sentinel lymph node metastases were found in 14% of the 68 cases. Invasion of the sentinel lymph node correlated with the presence of cutaneous satellite micrometastases. It is concluded that the presence of cutaneous satellite micrometastases may be an indication for the performance of sentinel lymph node biopsy, and this finding calls for a closer follow-up of these patients.

Adult↗
PubMed2005

Immunohistochemical investigation of alpha1 (IV) and alpha5 (IV) collagen chains in a broad spectrum of melanocytic tumours.

BACKGROUND: Cells of melanocytic naevi and cutaneous malignant melanomas (MM) are surrounded by a basement membrane (BM). AIM: To scrutinize any difference between the deposits of alpha1 (IV) and alpha5 (IV) collagen chains in melanocytic naevi and MM. METHODS: A total of 27 common melanocytic naevi, 11 dysplastic naevi, 21 atypical naevi (melanocytomas) including Spitz and non-Spitz types, as well as 24 MM were studied. Their phenotypic and functional characteristics defined by immunohistochemistry using a panel of antibodies, including those directed to the alpha1 (IV), alpha3 (IV) and alpha5 (IV) collagen chains. RESULTS: Almost all naevi and half the melanocytomas exhibited a strong positivity for the alpha1 (IV) collagen chain. By contrast, the remaining melanocytomas and MM presented a heterogeneous staining pattern for the alpha1 (IV) collagen chain. One third of the naevi, 23% of the MM without cutaneous micrometastasis and 83% of MM with cutaneous micrometastasis showed discrete cytoplasmic positivity for the alpha5 (IV) collagen chain. All other melanocytic tumours were negative for this antibody. Rare MM cells in transepidermal migration were stained with the anti-alpha1 (IV) or alpha5 (IV) collagen chain antibodies. No immunoreactivity for the alpha3 (IV) collagen chain was disclosed in any of the samples. CONCLUSION: We report the expression of alpha1 (IV) and alpha5 (IV) collagen chains in naevi and MM. The inconsistent staining pattern for alpha1 (IV) collagen chain in phenotypically atypical melanocytomas and in MM highlight the heterogeneity in both cell differentiation and stroma-tumour interactions. This biological aspect may be related to neoplastic progression and influence metastatic potential.

Cell Communication↗
PubMed2005

Ehlers-Danlos-like dermal abnormalities in women with recurrent preterm premature rupture of fetal membranes.

Preterm premature rupture of membranes (PPROM) likely results from weakening of the constituent connective tissue. It is uncertain if the alterations are limited to the fetal membranes or are also present in other sites such as the skin. The aim of the study was to compare the dermal structure of women suffering from recurrent PPROM with the dermis of both non-pregnant women and women with uneventful gestation. Skin biopsies were taken from 42 women who recently underwent PPROM, 33 women with uneventful gestation and 33 non-pregnant women. Histochemistry, immunohistochemistry, and electron microscopy were performed on these specimens and analyzed blindly. Morphologic changes were found in the dermis of most (33 of 42 at optical microscopy and 40 of 42 at ultrastructure) of the women suffering from PPROM. They were reminiscent of those found in some types of Ehlers-Danlos Syndrome (EDS). However, there was no clinical evidence suggesting a recognized form of EDS. We conclude that some cases of PPROM are a systemic connective tissue disorder representing a yet unidentified type of EDS.

Adult↗
PubMed2005

Tapping into the influence of keratinocyte allografts and biocenosis on healing of chronic leg ulcers: split-ulcer controlled pilot study.

BACKGROUND: Cultured keratinocytes may represent an alternative therapy aiming at boosting leg ulcer healing. There is no evidence-based study comparing objectively the healing rate of split-ulcer portions covered or not covered by cultured keratinocytes. OBJECTIVE: To assess the effect of cultured keratinocytes on the healing rate of leg ulcers. METHOD: Five applications of fresh (cela, XCELLentis, Ghent, Belgium) or frozen (CryoCeal, XCELLentis) cultured allogeneic keratinocytes were performed at weekly intervals to treat large leg ulcers (mean diameter > 5 cm) in four patients. A split-ulcer study was designed to secure a control area covered only by petrolatum gauze. Clinical, planimetric, bacteriologic, and immunohistologic assessments of the keratinocyte-treated and control parts of the ulcers were performed. RESULTS: Compared with controls, planimetry revealed a beneficial effect afforded by cryopreserved cultured keratinocytes on the ulcer healing rate of two of four ulcers (+12 and 81%). The healing effect was obtained on the ulcers associated with the lowest bacterial load. Cultured keratinocytes did not qualitatively and quantitatively modify the ulcer biocenosis. They did not affect the number of any type of inflammatory cells present in the granulation tissue (type I dermal dendrocytes, macrophages, T lymphocytes, granulocytes). No specific side effect of cultured keratinocytes was evidenced. CONCLUSION: In this small case series, it appears that cultured allogeneic keratinocytes may be helpful in the healing process of venous leg ulcers. However, a clean wound with reduced bacterial load seems to be the prerequisite condition for obtaining a beneficial effect.

Aged↗
PubMed2005

Vascularity and fractal dimension of the dermo-epidermal interface in guttate and plaque-type psoriasis.

BACKGROUND: Histological structures of the skin are often irregular in size and shape. Euclidean geometry and fractal analysis are complementary for assessing distinct aspects of their dimensions. OBJECTIVE: To determine and compare the variations in shape of the dermo-epidermal junction and the size of the superficial vessels in psoriatic lesions. METHOD: The relative microvasculature area and the fractal dimension D of the dermo-epidermal interface were measured inside and outside growth-stunted guttate lesions (n = 22) and expanding plaques (n = 37) in psoriasis of the trunk. RESULTS: The median D values of the dermo-epidermal interface were significantly larger (p < 0.01) in psoriatic plaques (D = 1.15) than in guttate lesions (D = 1.08), and these D values on lesional skin were significantly larger (p < 0.01) than in the uninvolved skin (D = 1.03). The microvasculature was significantly (p < 0.01) more developed in lesional (plaque: 13%, guttate: 8.20%) than in uninvolved skin (3.60 and 3.85%). No correlations were found between the relative microvasculature areas and the D values of the dermo-epidermal interface, both in the uninvolved and lesional skins of each psoriatic type. CONCLUSION: The absence of a relationship between modulations of the dermo-epidermal junction and vascular hyperplasia, both in expanding and stable psoriasis lesions, suggests that these events are regulated by different mechanisms and do not depend on each other.

Biopsy↗
PubMed2005

Distinct expression patterns of alpha1 (IV) and alpha5 (IV) collagen chains in cylindroma and malignant cylindroma.

Cutaneous cylindromas are considered to derive from cells of the sweat gland apparatus. The composition of the thick hyaline eosinophilic basement membrane (BM)-like zone surrounding epithelial aggregates in cylindromas is similar to that of the dermo-epidermal junction. The presence of type IV collagen has been documented, but the distribution of the different constitutive a chains of collagen IV has not been studied so far. Alterations in the expression of these alpha chains have been described in some other conditions including basal cell carcinomas, testes with spermatogenic dysfunction and colorectal carcinomas. The aim was to study the distribution of the alpha1 (IV) and alpha5 (IV) collagen chains in cylindromas and malignant cylindroma, and to compare it with the BM of sweat glands. Seven cylindromas and one malignant cylindroma were studied. They were formalin-fixed and paraffin-embedded before processing for immunohistochemistry. Immunostaining was assessed using the avidin-biotin-peroxidase technique with antibodies directed to the alpha1 (IV) and alpha5 (IV) collagen chains. In all cylindromas, a thin continuous and sharply limited immunolabelling for the alpha1 (IV) collagen chain was abutted to the tumoral cell aggregates. A speckled immunoreactivity was found in the rest of the hyaline sheath. Globular structures encased in the cell aggregates also exhibited a thin peripheral rim positive for the alpha1 (IV) collagen chain. The immunoreactivity was faint and granular in the center of the globules. With the antibody directed against the alpha5 (IV) collagen chain, 3 cylindromas did not show any staining, 2 cases presented discrete focal positivity in the mid-part of the BM-like zone, and 2 cases exhibited a positive staining pattern similar to that observed for the alpha1 (IV) collagen chain, but with a focal and more discrete intensity. The malignant cylindroma showed a linear immunoreactivity for the alpha1 (IV) collagen chain undistinguishable from the pattern seen in the benign cylindromas. No immunoreactivity was present for the alpha5 (IV) collagen chain in the malignant neoplasm. As reported for other BM components, the expressions of the alpha1 (IV) and alpha5 (IV) collagen chains are altered in the BM-like zone surrounding the epithelial clumps in cylindromas. The molecular alteration is probably related to the ultrastructural particularities of this structure. The distinctive patterns of expression of the alpha1 (IV) and alpha5 (IV) collagen chains may be related to the histogenic sudoral origin of cylindromas without any relationship with the benign or malignant nature of the neoplasm.

Carcinoma, Adenoid Cystic↗
PubMed2004

Hypogonadism in a patient with a mutation in the luteinizing hormone beta-subunit gene.

A 30-year-old man who presented with delayed puberty and infertility was found to have hypogonadism associated with an absence of circulating luteinizing hormone. The patient had a homozygous missense mutation in the gene that encodes the beta subunit of luteinizing hormone (Gly36Asp), a mutation that disrupted a vital cystine knot motif and abrogated the heterodimerization and secretion of luteinizing hormone. Treatment with human chorionic gonadotropin increased circulating testosterone, promoted virilization, and was associated with the appearance of normal spermatozoa in low concentrations. This case illustrates the important physiological role that luteinizing hormone plays in male sexual maturation and fertility.

Adult↗
PubMed2004

Mycosis fungoides progression and chronic solvent exposure.

The effect of repeated exposure to specific chemicals on the initiation or progression of mycosis fungoides (MF) remains unsettled. A patient with low-grade patch stage MF progressively developed MF plaques restricted to his arms, and a tumour on his right thigh. These areas were subject to repeated exposure to solvents. His thigh was indeed in close contact with his trousers pocket where he used to store a wiping rag drenched into white spirit and cellulosic thinner. Immunophenotyping these lesions revealed a dense LCA+, CD2+, CD3+, CD4+, CD5+, CD7+, CD45+, CD45RO+ T-cell infiltrate admixed with many factor XIIIa+ dendrocytes. T-cell receptor rearrangement analysis identified a monoclonal T-cell infiltrate. An internal work-up remained negative. Stopping further solvent exposure failed to improve his condition. Oral corticotherapy combined with low-dose interferon-alpha2a halted disease progression. This observation suggests that long-term solvent exposure may trigger MF and hasten its progression from the patch stage to the plaque and tumour stages.

Adrenal Cortex Hormones↗
PubMed2004

Revisiting the gender-linked melanoma burden.

BACKGROUND: Much is known about the worldwide rising incidence of skin cancers in the white populations. However, contradictory reports have been presented about a gender-linked risk for malignant melanoma (MM). OBJECTIVE: To review the recent epidemiological information about primary and metastatic MM in south-east Belgium. METHODS: Laboratory records of primary MM according to age and gender were compared per 3-year periods from 1988 to 2002. The numbers of MM per decade of patient age were corrected with regard to the number of citizens in the defined periods of age. This led to the calculation of the rate of estimated prevalence (REP). The same assessments were performed on 187 sentinel lymph node biopsies collected during the last 3-year period. RESULTS: A total of 1,051 primary MM in women and 594 primary MM in men were diagnosed over the 15-year period. The female-to-male ratio rose by 24% over time, with a mean value of 1.77. The most recent years showed a marked increase both in the numbers and REP of primary MM. This situation was present in both genders, although it was most prominent in women of the reproductive age. MM metastases were found in 38/187 sentinel lymph nodes with a female-to-male ratio of 2.17. The age distribution for all sentinel lymph node biopsies copied that of primary MM, but the vast majority of the nodal metastatic MM was found in patients older than 50 years. The ratio between MM metastases and primary MM reached 6.1% (12/198) in men and 6.9% (26/378) in women. CONCLUSION: A recent increase in primary MM incidence was observed in our laboratory. The most likely cause is ascribed to more sensitive MM detection using the combination of clinical dermoscopy and laboratory immunohistochemistry. During the past 15 years, women were more affected than men by both primary and metastatic MM. The gender difference in incidence of primary MM has progressively widened due to an increased incidence in young and middle-aged women. By contrast, nodal metastatic MM mostly affected postmenopausal women.

Adolescent↗
PubMed2004

Immunohistochemical aid at risk stratification of melanocytic neoplasms.

There is increasing awareness of the population about the risk of cutaneous melanoma. In recent years, some improvement was gained in the early recognition of clinical warning signs using dermoscopy. As a result, the number of puzzling cases exhibiting limited classical clues for malignancy are submitted to the dermatopathologist. Thus, the risk of microscopic uncertainty or misdiagnosis may be increasing. The aim of the study was to assess retrospectively the contribution of immunohistochemistry in establishing the histological diagnosis of 520 melanocytic neoplasms. According to the disease evolution and the histological presentation, 6 profiles of phenotypical expressions were distinguished.

Antibodies, Monoclonal↗
PubMed2004

Updating trends in cutaneous cancers in south-east Belgium.

From data collected in a dermatopathology laboratory, the ratios between the numbers of specific cancers represent good markers for identifying any epidemiological shift in their prevalence and incidence among the reference population. The objective of the present study was to assess the ratios of the annual incidence of skin cancers in the Mosan region and Ardennes of Belgium over the past 6 years, and to compare the data with previous similar evaluations. A total of 7,640 skin cancers were collected and compared with regard to age and gender. Changes in time show that the trend of the increase in incidence of malignant melanoma (MM) is more impressive than that of squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). The age distribution of BCC and SCC confirms the increasing risk with ageing. By contrast, there is a steady decrease over the past decade in the mean age for MM, teenagers and young adults now form an expanding proportion of MM patients. There is an ongoing trend in diagnosing an increased number of skin cancers in our laboratory. This trend is particularly obvious for MM affecting young adults.

Adolescent↗