Search PubMed⌕ Search

Biomedical subjects

W A Van Vloten

Publications and source records attributed to W A Van Vloten.

At least 19 recordsLinked to original sources
PubMed2001

Lymphomatoid papulosis in children: a study of 10 children registered by the Dutch Cutaneous Lymphoma Working Group.

Lymphomatoid papulosis (LyP) is a chronic recurrent self-healing condition, with histological features suggestive of a malignant lymphoma. Only a few cases have been described in children. We report 10 children with this skin disease and compare them with the adult type of LyP and childhood cases described in the literature. Although LyP has the same clinical picture and histology in both age groups, in contrast with the adult type no transformation into malignancy has been described in childhood.

Adolescent↗
PubMed1999

Sézary syndrome in a young man with severe atopic dermatitis.

Sézary syndrome (SS) is a rare cutaneous T-cell lymphoma. SS usually develops de novo. We describe a 23-year-old man with a proven history of severe atopic dermatitis since childhood, who developed SS. This case contributes to the discussion about the possibility of a relationship between inflammatory dermatitis, atopy and subsequent SS. We provide criteria that should be fulfilled to define such an association.

Adult↗
PubMed1999

CD11b+ cells and ultraviolet-B-resistant CD1a+ cells in skin of patients with polymorphous light eruption.

After ultraviolet exposure Langerhans cells (epidermal CD1a+ cells) disappear from the healthy skin, and CD11b+ macrophage-like cells, which are reported to produce interleukin-10, appear in a matter of days. These phenomena are related to the ultraviolet-induced local suppression of contact hypersensitivity reactions. A defect in this suppression might allow inadvertent immune reactions to develop after ultraviolet (over)exposure; i.e., it could cause ultraviolet-B-induced polymorphous light eruption. In order to test this we first exposed buttock skin of eight healthy volunteers to six minimal erythema doses from Philips TL12 lamps, and indeed observed a dramatic disappearance of CD1a+ cells 48 and 72 h later, at which time the number of CD11b+ cells increased in the dermis, and some occurred in the epidermis. The epidermis thickened and showed large defects, filled by CD11b+ cells, just below the stratum corneum. In 10 patients with polymorphous light eruption (five with a normal minimal erythema dose and five with a low minimal erythema dose) CD1a+ cells were present in the epidermis as well as in the dermis before exposure. Strikingly, these cells were still present in considerable number at 48 and 72 h after exposure to six minimal erythema doses. CD11b+ cells already present in the dermis before ultraviolet exposure, increased after ultraviolet exposure, and subsequently also invaded the epidermis. Despite the six minimal erythema doses, there were no apparent defects in the epidermis of the polymorphous light eruption patients. This deviant early response to ultraviolet radiation is likely to be of direct relevance to the polymorphous light eruption and is perhaps useful as a diagnostic criterion.

Adult↗
PubMed1998

Delusions of parasitosis. A psychiatric disorder to be treated by dermatologists? An analysis of 33 patients.

Delusions of parasitosis is a rare disorder in which patients have the false and fixed belief that they are infested by parasites. It is a psychiatric disorder, but patients usually present to a dermatologist and referral to a psychiatrist is almost always rejected. Treating a patient with delusions of parasitosis requires patience and tact. The neuroleptic pimozide is the treatment of choice, but a significant problem is convincing the patient to take the drug. We report a study of 33 patients (13 men and 20 women) with delusions of parasitosis. The mean age at onset was 56.9 years and the mean duration of symptoms before attending the department of dermatology was 1.3 years. Pimozide (Orap) was prescribed for 24 patients, but only 18 patients took it. Follow-up information was available for 18 patients: five had full remission, four were less symptomatic, five were unchanged and four had died of unrelated causes.

Adolescent↗
PubMed1995

Topical 5-fluorouracil in the treatment of Darier's disease.

Two patients suffering from therapy-resistant Darier's disease were treated with topical 5-fluorouracil (5-FU). The drug was applied in a concentration of 1% in a cream base, once daily, in left-right comparison with either 7.5% salicylic acid in petrolatum or 0.05% vitamin A acid cream. Both patients were on long-term treatment with oral retinoids. After 1 week of treatment, a considerable improvement was already apparent on the 5-FU-treated side, in comparison with the salicylic acid- and vitamin A acid-treated sides. Subsequent treatment of all skin lesions with 5-FU for a further 2 weeks resulted in complete clearance of the lesions. Remission periods were of 2-6 months duration. There were no significant adverse effects of treatment. Haematological parameters remained unchanged during the therapy. Topical 5-FU is a safe and useful addition to currently available treatments for Darier's disease.

Acitretin↗
PubMed1993

Concentrations of nitrogen mustard in the air during topical treatment of patients with mycosis fungoides.

Acute and chronic side-effects have been reported during topical treatment of mycosis fungoides with nitrogen mustard (HN2). In order to estimate the risk for the nurse applying topical HN2, the concentration of HN2 in the air during treatment was measured. Air samples were obtained before, and during the 20-min treatment period close to the nurse and patient, and continuously at a distance of 1 m from the patient. The mean concentration of HN2 in the air during treatment was 0.036 mg/m3. Immediately after treatment the concentration dropped to 0.004 mg/m3. The mean cumulative concentration in the room during the 3 1/2 h of the experiment was 0.012 mg/m3. If the MAC (maximal allowable concentration) value of 0.05 mg/m3 for the comparable sulphur mustard is used as a guideline, then with a treatment procedure of 20 min this level is not exceeded. Nevertheless, it is important to minimize the exposure of nursing staff to HN2.

Administration, Topical↗
PubMed1990

UV-B-induced bullous pemphigoid restricted to mycosis fungoides plaques.

We describe a 77-year-old female patient with plaque-stage mycosis fungoides (MF) who developed bullous lesions in lesional skin only, while receiving short-wave ultraviolet radiation (UV-B) therapy. Histopathological and immunohistochemical examination resulted in a diagnosis of bullous pemphigoid (BP). Withdrawal of the UV-B treatment and application of a high-potency topical corticosteroid cream resulted in a rapid regression of the BP. As the bullous lesions were strictly confined to the MF plaques, the cutaneous infiltrate was probably involved also in the development of the BP. To our knowledge, this is the second case report of the coexistence of MF and BP and the first one in which the BP might be UV-B-induced.

Aged↗
PubMed1988

The efficacy of histopathological criteria required for diagnosing dysplastic naevi.

The efficacy of specific histopathological features for diagnosing dysplastic naevi was established by comparing their frequency in 62 dysplastic naevi, from 36 patients with the dysplastic naevus syndrome, with those in 326 ostensibly benign naevocellular naevi derived from a group of 67 autopsy cases. Individual diagnostic features had a low sensitivity, a low specificity or low predictive values. Discriminant analysis showed that the presence of dust-like melanin, irregular naevoid nests, markedly increased junctional activity and melanocytic nuclei equal or larger in size than overlying keratinocyte nuclei were the most discriminating features. Using two or more of these criteria plus a lymphocytic infiltrate as an obligatory diagnostic criterion, a reasonable efficacy could be reached for dysplastic naevi. Based on these combinations of criteria the prevalence of histologically proven dysplastic naevi in the autopsy group would be 10%. Lesions with all these four discriminating features were found in half of the patients from the dysplastic naevus syndrome group, but were absent in the autopsy group. We suggest that such severely atypical dysplastic naevi may be indicative of patients at high risk for developing malignant melanoma.

Adolescent↗
PubMed1987

Diffuse large cell lymphomas of follicular center cell origin presenting in the skin. A clinicopathologic and immunologic study of 16 patients.

This report describes the clinical, histologic, and immunologic characteristics of 16 diffuse large cell lymphomas of follicular center cell origin with only skin lesions at presentation. These patients presented with nodular and tumorous skin lesions, which in 10 of 16 cases were confined to a circumscribed area on the trunk. Four patients, all elderly women, presented with skin tumors on the lower legs. Histologically, these 16 lymphomas showed nonepidermotropic diffuse dermal infiltrates, mainly consisting of large follicular center cells, with a variable admixture of small cleaved cells, immunoblasts, T-lymphocytes, and macrophages. The relative numbers of large cleaved and large noncleaved cells, respectively, varied considerably in these lymphomas. Immunophenotypically, almost all lymphomas expressed monotypic surface immunoglobulins and HLA-DR antigens, whereas all lymphomas were reactive with B-cell-associated monoclonal antisera B1, Leu-14, and/or To15. Three of four elderly female patients presenting with disease on the lower legs died. Of the 12 other patients, 11 are currently alive and in complete remission, which suggests a favorable prognosis for this type of cutaneous large cell lymphoma.

Adult↗
PubMed1986

Quantitative electron microscopy in the early diagnosis of cutaneous T-cell lymphomas. A long-term follow-up study of 77 patients.

Previous studies have demonstrated that quantitative analysis of nuclear convolution of lymphoid cells in electron micrographs is a valuable method of differentiation between well-established cutaneous T-cell lymphoma (CTCL) and chronic benign skin disease. The usefulness of these methods in the diagnosis of early and controversial cases of CTCL has, however, not been fully established. In the present study the authors compared the diagnostic accuracy of two different quantitative ultrastructural methods on a group of 77 patients suspected of having early CTCL. These methods included measurements of the nuclear contour index (NCI) as well as a simple counting of the number of sharply angled nuclear indentations of at least 75 lymphoid cells present on electron micrographs. The results were correlated with the final diagnosis after a follow-up period of 1 to more than 10 years. Measurement of the NCI proved to be a much more sensitive method than determination of the percentage of cells having no sharply angled nuclear indentations (sensitivity, 96% and 62%, respectively). None of these two methods produced false-positive diagnoses. It is concluded that quantitative ultrastructural methods, in particular, NCI measurements, are an important adjunct in the diagnosis of CTCL, even in early and controversial cases.

Cell Nucleus↗