Renewal and differentiation of keratinocytes cultured on dead de-epidermalized dermis.

Human keratinocytes grown at an air-liquid interface on dead de-epidermalized dermis exhibit a pattern of organization similar to that seen in vivo. Cell renewal is limited to the basal layer. The cell cycle time determined after 7 days of culture, using a percentage labelled mitoses (PLM) technique, was about 15 h. This result is comparable with published data for cultivated keratinocytes but is shorter than the parameter proposed for epidermis in vivo. Appearance of labelled cells in the granular layer was observed 4 days after pulse labelling. Despite this high cell renewal, a normal cell differentiation with expression of various keratinization markers was maintained.

Graft versus host reaction. An ultrastructural study.

Graft versus host reaction (GvH) following leukocytic transfusions occurred in a 34-year-old man with a generalized lymphosarcoma. Histologic and ultrastructural studies were performed, with special reference to dyskeratotic cells scattered in the epidermis. These cells are usually considered to be a constant and important feature of GvH reaction. Dense aggregation of tonofilaments, including cytoplasmic organelles and loss of desmosomes, were seen in dyskeratotic cells. Several intracellular desmosomes with tonofilaments bound to their attachment plaque were observed. Some of these cells were able to reach the horny layer; some others were phagocytosed by neighboring keratinocytes. These cells could be the result of a toxic damage to the epidermis, provoked by the immunologic phenomenon implicated in GvH reaction. Later in the clinical course, bullae formations occurred, showing some features of toxic epidermal necrolysis (TEN), as well as features of GvH reaction.

[Validity of the tympanic infrared thermometer in geriatric inpatients]. / De validiteit van de tympane infrarood thermometer bij gehospitaliseerde, geriatrische patiënten.

The purpose of this study was to assess the agreement between rectal temperature and infrared emission detection (IRED). The specificity and sensitivity, the positive predictive value and the negative predictive value were calculated. It was a prospective, observational and unblinded study. Thermoscan-pro-1 was used to collect pairs of data in 41 patients, all hospitalised on an acute geriatric ward during a 4-month period. 41% of the patients were febrile. The 'bias' between rectal and tympanic measurement (left ear) was -0.64 degree C (d) and the standard deviation 0.58 degree C (s). The '95% Confidence Interval' for the bias was -0.82 degree C and -0.46 degree C. The '95% limits of agreement' between the rectal measurement and the tympanic measurement (left ear) was -1.78 degrees C and 0.50 degree C. Regression analysis taught us that bias was increasing with increasing temperature. If we take into account one measurement with the IRED ear thermometry, the sensitivity was 41%, the specificity 83%. The positive predictive value was 64% en the negative predictive value 67%. We can conclude that the IRED ear thermometry is not a valuable alternative for the rectal, digital thermometry in the elderly, frail and febrile hospital inpatients.

[Sebaceous cutaneous carcinoma. Value of early cytological test]. / Carcinome sébacé cutané. Intérêt de l'examen cytologique précoce.

Sebaceous carcinoma is a skin tumour which frequently metastases to the visceral organs. Needle biopsy is needed for rapid diagnosis. We observed a case in a 65-year-old patient who had a tumour formation below the right maxillary angle and homolateral justamandibular lymph node enlargement. Cytology of the needle biopsy showed a double cell population: small anaplastic cells and an agglutinated cell mass with peripheral maturation and sebaceous differenciation. Treatment was surgical with homolateral node dissection and secondary plasty. The tumour was large, non-encapsulated with local infiltration. On light microscopy, two cell populations were seen. Evident sebaceous differentiation was confirmed by histochemical staining. Immunolabelling confirmed the epithelial nature of the tumour. The clinical diagnosis of sebaceous carcinoma is difficult. Early cytology is needed to identify the two cell components when other cytological signs do not allow a positive diagnosis.

[Epidemiology and etiopathogeny of necrotizing fasciitis and streptococcal shock syndrome]. / Epidémiologie et étiopathogénie des fasciites nécrosantes et du syndrome de choc streptococcique.

A significant increase in the frequency of necrotizing fasciitis caused by streptococci of group A has recently been noted. The disease usually appears in individuals without obvious risk factors. The initial lesion is often quite ordinary, and the evolution towards a toxic shock very swift. This evolution can be summarized as follows: 1) localized infection; 2) bacteraemia with circulating toxins and soft tissue necrosis; 3) production of cytokines by the immune cells of the host, leading to a rapidly irreversible toxic shock Serotypes 1, 3, 12 and 28 of group A streptococcus are usually involved. The virulence of some serotypes might be explained by the acquisition of a toxic gene. The sensitivity of the host is linked to the genetic expression of the V. beta. elements on the surface of lymphocytes. Antibiotics cannot save the patient when necrotizing fasciitis is installed. Surgery must be massive and performed early.

[Plexiform fibrohistiocytic tumor]. / Tumeur plexiforme fibrohistiocytaire.

Plexiform fibrohistiocytic tumour has been recently described by Enzinger and Zhang. This is a rare tumour with low grade malignancy which requires large excision. We report two cases, one occurring in a 58-year-old man, presenting a voluminous painless mass of 5 cm on his hand, the other occurring in a 9-year-old boy consulting for a nodule on the chest. On histological examination this dermal hypodermal tumour is characterized by a proliferation of histiocytic-like cells grouped in nodules, where they are associated with multinucleated osteoclastic-like cells and a proliferation of fibroblastic-like cells grouped in fascicles, anastomosing in a plexiform pattern. Immunohistochemistry and ultrastructural aspects are described. Differential diagnosis and histogenesis are discussed.

[Primary and isolated cutaneous lymphomatoid granulomatosis following heart-lung transplantation]. / Granulomatose lymphomatoïde à localisation cutanée isolée après une transplantation cardio-pulmonaire.

BACKGROUND: Lymphomatoid granulomatosis is an Epstein-Barr virus-associated B-cell lymphoproliferative disease. It is angiocentric and angiodestructive and involves the lungs, central nervous system and skin. Exclusive cutaneous involvement is rare and may be associated with a better outcome. Contrarily to the extra-cutaneous forms of lymphomatoid granulomatosis, it is difficult or impossible to detect Epstein-Barr virus DNA sequences in primary and isolated cutaneous lymphomatoid granulomatosis. CASE REPORT: A 54-year-old woman developed erythemato-violaceous lesions on both legs 3 years after a heart-lung transplantation. The diagnosis of erythema multiforme and of drug-induced vasculitis were first made. Because of fever and of the rapid extension of the lesions, the patient was hospitalized. The histologic examination of the first lesions showed a perivascular infiltrate, without epidermotropism, composed of histiocytes, lymphocytes and plasma cells. Immunohistochemistry revealed the presence of a predominantly T-cell infiltrate with some large B cells. Subsequent biopsies were diagnosed as high grade B-cell lymphoma. Polymerase chain reaction analysis as well as in situ hybridation study showed the presence of Epstein-Barr virus load in the lesions. There was however no serologic evidence of viral reactivation. Extensive systemic evaluation revealed no visceral or bone marrow involvement. Despite antiviral treatment and CHOP polychemotherapy, the patient died 3 months after her admission. DISCUSSION: This observation of lymphomatoid granulomatosis is particular because of its exclusive cutaneous involvement associated with a fulminant evolution to high grade B lymphoma. The presence of a context of iatrogenic immunosuppression underlies the role of altered immune cellular functions in the initiation and/or progression of lymphomatoid granulomatosis and strengthens the role of a viral agent in its pathogenesis. We suggest that the presence of Epstein-Barr virus, which is generally not associated with the isolated cutaneous forms of lymphomatoid granulomatosis, may have played a role in this fulminant evolution to high grade B lymphoma.

[Streptococcus beta hemolytic necrotizing fasciitis. 5 cases in the Brussels area]. / Fasciite nécrosante à streptocoque beta hémolytique du groupe A. Cinq cas dans la région bruxelloise.

In the Brussels area five cases of necrotizing fasciitis occurred during the past two years in patients devoid of any pathology likely to lower the immune defence mechanisms. Alcoholism and the use of non-steroidal anti-inflammatory drugs seem to act as contributory factors. Necrotizing fasciitis develops alone or as complication of a pre-existent dermo-hypodermic infection. A massive use of antibiotics and a wide surgical slitting up failed to prevent a fatal issue in all five patients. Extremely early massive surgery remains vital in this disease.

[Stings, bites and other adventures...]. / Piqûres, morsures et autres aventures....

Most of us live in cities and nature seems beneficial. Unfortunately, invertebrates and vertebrates may be aggressive. We will try here a review of the diseases caused by arthropods and other noxious animals. Injuries caused by the following insects will be described: mosquitoes, flies, fleas, bees, wasps and ants, bugs, beetles, butterflies and caterpillars. In the class arachnida: spiders, scopions, ticks and mites. Among invertebrates: leeches, anemons, corals, sea urchins, sponges and mollusca. Noxious or venomous vertebrates will not be forgotten. Basic and practical attitudes are proposed.

[Skin cancers following organ transplantation: clinical and therapeutic approach]. / Cancers cutanés après transplantation d'organes: approche clinique et thérapeutique.

Three of the most frequent cancers occurring in transplant recipients affect the skin: Kaposi's sarcoma and spino- and baso-cellular carcinomas. The two latter neoplasms are often preceded by precancerous lesions such as keratosis, warts, porokeratosis and keratoacanthomas. We describe the clinical presentations of these lesions and detail the possible therapies in each case: local treatment, surgery, modulation of immunosuppression, and chemotherapy.

[The dermatology department]. / Le Service de Dermatologie.

The department of dermatology has developed a broad clinical activity with a particular expertise in oncology, allergology, psoriasis and gynecological dermatology. Research has also been developed in these areas.

[Phototoxic contact phytodermatitis: clinical and biological aspects]. / Phytodermatite phototoxique de contact: aspects clinique et biologique.

We report the case of a 39-year-old patient, gardener, who develops, during a beautiful sunny summerday, an erythemato-bullous eruption of the forearms. The diagnosis is a Contact Phototoxic Phytodermatitis (dermite des prés, dermatitis bullosa striata) with a classical presentation. This clinical observation gives us the opportunity to remind of the clinical and biological aspects of this dermatosis, whose frequency is probably underestimated, related to an often rapidly favourable evolution.