[Febrile cellulitis surrounding a scar revealing a large immunoblastic B-cell lymphoma]. / Dermohypodermite fébrile péricicatricielle révélatrice d'un lymphome B immunoblastique à grandes cellules.

BACKGROUND: Secondary skin sites of lymphoma appear in the advanced stages of the disease. We report the first case of a pericicatricial skin infiltration, mimicking febrile dermohypodermitis, revealing diffuse immunoblastic large B-cell non-Hodgkin's lymphoma. PATIENTS AND METHODS: Four months after decompressive cervical laminectomy, a 56-year-old man presented an inflammatory pericicatricial patch evoking cellulitis in a setting of hyperthermia and lymphadenopathy. Blood cultures and bacteriological analysis of skin biopsy samples were negative. The images showed infiltration of the soft subcutaneous areas and polyadenopathy. Two weeks later, several subcutaneous nodules appeared on the trunk. Histological analysis and immunolabelling pointed to immunoblastic large B-cell non-Hodgkin's lymphoma. A clone of B lymphocytes CD45+, CD20+, CD79a+, Bcl2+, CD5+, MUM1+, CD3-, CD10-, CD23- and Bcl6- was seen. The remainder of the extension examination was negative. CHOP-rituximab polychemotherapy resulted in complete regression of all lesions, notably the inflammatory cervical plaque. DISCUSSION: Secondary skin manifestations of lymphoma are generally non-specific (pruritus, ichthyosis, purpura, etc.) rather than specific in terms of lymphoid infiltration. As in our patient, certain cutaneous sites of lymphoma may have a misleading clinical presentation, histological analysis alone was able to provide a conclusive diagnosis. In our patient, the highly specific infiltration seen around the entire scar could either suggest a Koebner phenomenon or point to a role of the cutaneous aggression within the development of an inflammatory process contributing to pericicatricial infiltration by lymphoid cells. Locoregional invasion from the osseous part of the cervical spine and not macroscopically diagnosed during neurosurgery could also be responsible.

[Syringotropic and pilotropic cutaneous T-cell lymphoma without follicular mucinosis]. / Mycosis fongoïde syringotrope et pilotrope sans mucinose folliculaire.

BACKGROUND: Mycosis fongoides rarely exhibits predilection for infiltration of hair follicles and eccrine glands. We report the case of a patient with cutaneous T-cell lymphoma with syringotropism and pilotropism without follicular mucinosis. CASE REPORT: A 51-year-old man presented with erythematous infiltrated patches with alopecia and anhydrosis, cystic lesions, comedon-like lesions, follicular keratosis and an ulcer over the lower left leg. Clinical examination revealed no palpable adenopathy or hepatosplenomegaly. The patient complained about hypohydrosis. Histological examination of skin biopsies evidenced pilotropic cutaneous T-cell lymphoma without follicular mucinosis. Immunohistological examination and T-cell receptor B-chain gene rearrangement analysis showed a clonal population of T-cells. Moreover sweat glands and sweat ducts were infiltrated by atypical lymphocytes with syringolymphoid hyperplasia. DISCUSSION: Syringolymphoid hyperplasia and folliculotropism without follicular mucinosis are rarely seen in mycosis fongoides. Deep biopsies of adnexal structures are required for this critical diagnosis and clonal rearrangement of TCR genes is a reliable means of assessing clonality. Syringolymphoid hyperplasia and pilotropism without mucinosis are variants of cutaneous T-cell lymphomas.

Fluorogenic polypropionate fragments for detecting stereoselective aldolases.

A series of fluorogenic polypropionate fragments has been prepared. These undergo retroaldolization to an intermediate aldehyde that liberates the fluorescent product umbelliferone by a secondary beta-elimination reaction. leading to a >20-fold increase in fluorescence (lambda(em) = 460 +/- 20 nm, lambdaex = 360 +/- 20 nm). By applying the principle of microscopic reversibility to the reversible aldol reaction, we can use these substrates to detect stereoselective aldolases. Test substrates are available to probe the classical cases of syn- and anti-selective aldolization (11a-d), Cram/ anti-Cram-selective aldolization (10a-d), and double stereoselective aldolization (3a-h). The selectivity of aldolase antibody 38C2 for these substrates is demonstrated as an example. The assay is suitable for high-throughput screening for catalysis in microtiter plates, and therefore provides a convenient tool for the isolation of new stereoselective aldolases from catalyst libraries.

[Plasma levels of psoralens after celery ingestion]. / Etude des taux plasmatiques de psoralènes après ingestion de céleri.

Psoralens are photosensitizing substances present in many vegetables, some of which are routinely consumed. These vegetables are responsible for contact phytophotodermatitis, but it was agreed that they did not produce photodermatitis when taken orally. Ljunggren has recently questioned this concept by reporting a case of phototoxic accident which occurred after ingestion of 450 grams of celery roots (Apium graveolens). In a study in healthy volunteers we looked for psoralens in blood and analyzed the cutaneous photosensitivity by the minimal phototoxic doses (MPD) method, after ingestion of celery in large amounts (500 grams and more). Plasma concentrations of psoralens were inexistant in all subjects and at all sampling times, and no phototoxic reaction was detected by MPD. Celery roots, therefore, do not seem to be photosensitizing, even after ingestion in large amounts, but they might increase the risk of phototoxicity in PUVA-therapy. The same applies to fennel and parsnip.

[Problems posed by the therapeutic use of photosensitizers in dermatology]. / Problèmes posés par l'utilisation thérapeutique des photosensibilisateurs en dermatologie.

Three phototherapeutic regimens with photosensitization are now used in dermatology: PUVA (psoralen + UVA), TUV (crude coaltar + UV), PRT (phototherapy with hematoporphyrin derivative). The efficiency of PUVA and TUV is well known in several dermatoses. PRT is now being tested experimentally. For TUV, the lack of a standardized regimen does not allow a clear-cut evaluation of the therapy. For PUVA, late side-effects, particularly carcinogenicity have to be considered. To improve efficiency and minimize the side-effects of PUVA some procedures, such as association with retinoïds, pharmaco-kinetic studies for individual adaptation of the therapeutic regimen and the use of new less mutagenic psoralens are helpful. The persistent phototoxicity following treatments with hematoporphyrin derivative constitutes the major side-effect observed, for this phototherapy.

Buschke-Ollendorf syndrome. An electron microscopic study.

Two identical twins with the Buschke-Ollendorf syndrome (dermatofibrosis lenticularis disseminata with osteopoikilosis) are described. Ultrastructurally elastic fibers show clumps of electron-lucent elastin material coated with fine fibrils. The fibroblasts show enlarged endoplasmic reticulum containing abnormal fibrillar material. Juvenile elastoma seems to be a better term than dermatofibrosis. The pathogenesis of the elastic defect is discussed.

[Cytogenetic aspects of diffuse scleroderma. Structural anomalies and sister chromatid exchanges]. / Aspects cytogénétiques de la sclérodermie généralisée. Anomalies structurales et échanges de chromatides-soeurs.

Structural chromosome anomalies (1 477 cells examined) and sister chromatid exchanges after two replication cycles with BrdU (771 cells studied) were evaluated in 12 patients with diffuse scleroderma and having received no recent or important irradiation. The increase of structural anomalies, chromatidic as well as chromosomal, is always low, inconstant and cannot be considered as having a diagnostic value. Increase of sister chromatid exchanges could be a more sensitive method of investigation. In particular, it is not influenced by low doses of diagnostic X-rays.

[Pemphigus vulgaris and Kaposi sarcoma. Report of a new case (author's transl)]. / Pemphigus vulgaire et maladie de Kaposi. A propos d'un nouveau cas.

The occurrence of a Kaposi sarcoma during the course of a therapy for a pemphigus vulgaris is reported. Only five such associations have been previously described in the literature. On the other hand, several works have reported simultaneous occurrence of a Kaposi sarcoma with anomalies of the immune or lymphoïd systems (lymphoma, Hodgkin disease, Waldenström disease, mycosis fongoïdes. Hypothesis concerning the Kaposi sarcoma genesis can be suggested on the basis of these observations and remain to be confirmed.

Nevus lipomatosus cutaneous superficialis. An electron microscopic study of four cases.

Four cases of nevus lipomatosus cutaneous superficialis were studied under the electron microscope. The results showed the vascular origin of the fat cell and differentiation of young fat cells into mature fat cells. The findings are comparable to those observed in fetal adipogenesis.