Management of toxic epidermal necrolysis and related syndromes.

Toxic epidermal necrolysis and Stevens-Johnson syndrome are rare and life-threatening diseases that often configure as medical emergencies. The majority of cases are drug reactions. The clinical picture is one of widespread epidermal necrosis and mucosal erosions. Treatment is largely supportive and must be provided in an appropriate environment. The role of steroids and other potential disease-modifying therapies has yet to be fully established by controlled studies. The significant mortality associated with these conditions dictates that an understanding of these conditions is essential for all doctors.

Epstein-Barr virus-positive blastoid nasal T/natural killer-cell lymphoma in a caucasian.

T/natural killer (NK)-cell lymphoma is a subtype of non-Hodgkin's lymphoma, with frequent cutaneous involvement; it follows an aggressive course. Most cases are reported in Asia, and typically present with nasopharyngeal involvement. There is a distinct variant known as blastoid T/NK-cell lymphoma, which affects elderly, non-Asian patients, with absence of nasal involvement. We report a middle-aged caucasian man who had blastoid T/NK-cell lymphoma with nasal involvement.

A short-term screening protocol, using fibrillin-1 as a reporter molecule, for photoaging repair agents.

Photoaged skin is characterized by coarse and fine wrinkles. The mechanisms of wrinkle formation are undetermined, but appear to be due to changes within the matrix of the dermis and at the dermal-epidermal junction. Previous studies have identified marked reductions in procollagens I and III, collagen VII, and the fibrillin-rich microfibrillar apparatus in this area. Topically applied all-trans retinoic acid can repair photoaged dermal matrix, but this takes at least 6 mo of treatment. In this study, we have examined the abundance and distribution of fibrillin-1 prior to, and following, 192 wk of all-trans retinoic acid treatment. We have further developed a short-term protocol to determine the utility of potential repair agents, using fibrillin-1 as the marker for outcome. Individuals with clinically assessed severe photoaging were recruited to the study (n = 8). 0.025% all-trans retinoic acid, 5% sodium lauryl sulfate (irritant control), or vehicle were applied under occlusion to photoaged extensor forearm. A fourth control area was also occluded. After 96 h, punch biopsies were taken under local anesthesia and processed for either transmission electron microscopy or snap frozen. Frozen sections were prepared for immunohistochemistry and in situ hybridization immunohistochemistry. Electron microscopy revealed aberrant elastic fibers in the papillary dermis of photoaged forearm skin, with sparse microfibrillar apparatus and interstitial collagen. After application of 0.025% all-trans retinoic acid, there was increased deposition of both these dermal matrix components, with the aberrant elastic fibers no longer apparent. Significant increases (p < 0.05) were observed at the protein and mRNA levels for fibrillin-1 following all-trans retinoic acid and sodium lauryl sulfate treatments, with all-trans retinoic acid having a significantly greater effect than irritant control (p < 0.001); however, neither application had significant effect on the abundance of collagen VII or its mRNA. Investigation of collagen I synthesis revealed no difference following treatments. To ascertain the clinical relevance of using fibrillin-1 as a marker for photoaging, facial skin was biopsied at baseline and after long-term (192 wk) topical all-trans retinoic acid treatment (n = 5). Biopsies were wax-embedded and sections prepared for immunohistochemistry for fibrillin-1. Significant increases in the abundance of the microfibrillar apparatus was observed proximal to the dermal- epidermal junction (p < 0.001) following long-term all-trans retinoic acid application. This study indicates that all-trans retinoic acid can significantly affect fibrillin-1 content in photoaged skin. Furthermore, fibrillin-1 can be used as a "reporter" molecule in short-term protocols for testing the utility of topical agents in the repair of photoaged skin.

Distribution and expression of type VI collagen in photoaged skin.

BACKGROUND: Several of the characteristic clinical features of photoaged skin, including wrinkling, are thought to be dependent on changes in the dermal matrix brought about by chronic sun exposure. Such changes include reductions in collagens I, III and VII, an increase in elastotic material in the reticular dermis and a marked reduction in the microfibrillar glycoprotein fibrillin. OBJECTIVES: To examine whether type VI collagen, a microfibrillar collagen necessary for cell-cell and cell-matrix communication, is affected by the photoageing process. METHODS: Six healthy volunteers with moderate to severe photoageing were enrolled into the study. Immunohistochemistry and in situ hybridization histochemistry were used to examine the levels of type VI collagen in photoprotected and photoaged sites. RESULTS: In photoprotected skin, type VI collagen was concentrated in the papillary dermis immediately below the dermal-epidermal junction, around blood vessels, hair follicles and glandular structures. The distribution of type VI collagen was unchanged in photoaged skin, although we observed an increase in the abundance of the alpha3 chain of collagen VI in the upper papillary dermis, at its junction with the dermal-epidermal junction (P < 0.05). No alterations were observed for any alpha chain at the mRNA level. CONCLUSIONS: These studies suggest that chronic sun exposure (photoageing) has little or no effect on either the distribution, abundance or levels of expression of type VI collagen in human skin. Thus, type VI collagen, unlike other matrix components so far studied, appears to be relatively unaffected by the photoageing process.

Cytokine gene polymorphisms in psoriasis.

BACKGROUND: Cytokine production is under genetic control, and certain allelic variants of cytokine genes are associated with higher or lower cytokine production in vitro and in vivo. Psoriasis is associated with an overexpression in the involved skin of T-helper cell type 1 (Th1) cytokines, e.g. interferon (IFN) -gamma and tumour necrosis factor (TNF) alpha and relative underexpression of Th2 cytokines, e.g. interleukin (IL) -4 and IL-10. Objective We investigated the hypothesis that allelic variants of genes for a high production of Th1 cytokines or TNF-alpha, or conversely low production of Th2 cytokines might represent a risk factor for developing psoriasis. METHODS: Genotyping for IFN-gamma, IL-10, IL-4 and TNF-alpha was undertaken for 84 patients with psoriasis and compared with control data on file. RESULTS: Genotype frequencies showed no differences between patients and controls for IFN-gamma, TNF-alpha or IL-4. For IL-10, patients with late onset psoriasis (over 40 years) were more likely to be heterozygous at position - 1082 (P = 0.02), corresponding to intermediate production of IL-10 in vitro and in vivo. CONCLUSIONS: Psoriasis is not determined by a genotype consistent with high production of Th1 cytokines or low production of Th2 cytokines. Thus, the Th1 cytokine profile found in psoriatic plaques is most likely a consequence of local factors.

Lymphoepithelioid cell lymphoma (Lennert's lymphoma) presenting as atypical granuloma annulare.

We describe a case presenting as atypical granuloma annulare where the underlying diagnosis, confirmed by lymph node biopsy, was lymphoepithelioid cell lymphoma (Lennert's lymphoma). Lennert's lymphoma is a peripheral T-cell lymphoma which may follow a variable course and transform into an aggressive phase. Cutaneous manifestations of this condition have only rarely been reported in the literature. The presence of granulomas in the skin may have either obscured the lymphoma infiltrate or may have reflected a more generalized immune response to the underlying malignancy.

Management of toxic epidermal necrolysis.

Toxic epidermal necrolysis and Stevens-Johnson syndrome are rare, life-threatening drug reactions. Widespread epidermal necrosis and mucosal erosions lead to complications similar to those developing after extensive burns. Treatment is supportive. The role of steroids and other potential disease-modifying agents remains to be established by controlled studies.

Fibrillin-rich microfibrils are reduced in photoaged skin. Distribution at the dermal-epidermal junction.

Chronic sun exposure results in photoaged skin with deep coarse wrinkles and loss of elasticity. We have examined the distribution and abundance of fibrillin-rich microfibrils, key structural components of the elastic fiber network, in photoaged and photoprotected skin. Punch biopsies taken from photoaged forearm and from photoprotected hip and upper inner arm of 16 subjects with a clinical range of photoaging were examined for fibrillin-1 and fibrillin-2 expression and microfibril distribution. In situ hybridization revealed decreased fibrillin-1 mRNA but unchanged fibrillin-2 mRNA levels in severely photoaged forearm biopsies relative to photoprotected dermal sites. An immunohistochemical approach demonstrated that microfibrils at the dermal-epidermal junction were significantly reduced in moderate to severely photoaged forearm skin. Confocal microscopy revealed that the papillary dermal microfibrillar network was truncated and depleted in photoaged skin. These studies highlight that the fibrillin-rich microfibrillar network associated with the upper dermis undergoes extensive remodeling following solar irradiation. These changes may contribute to the clinical features of photoaging, such as wrinkle formation and loss of elasticity.

An open study of tissue adhesive in full-thickness skin grafting.

BACKGROUND: Securing full-thickness skin grafts (FTSG) by suturing is a time-consuming procedure, even in experienced hands. The advent of tissue adhesives has led to their use in a variety of surgical procedures, providing an acceptable alternative to conventional suturing. OBJECTIVE: Our purpose was to identify whether the tissue adhesive n-butyl-2-cyanoacrylate (NBCA) can be used to secure FTSG and to compare the outcome with conventional suturing. METHODS: Twenty-one patients with defects after Mohs micrographic surgery were enrolled into the study. An initial pilot study of 8 patients compared NBCA and sutures within individual grafts; the subsequent 13 patients had grafts secured with between 4 and 8 cardinal sutures and NBCA alone. RESULTS: No differences in healing, complications, or cosmetic appearance were observed between the sides secured with NBCA and with sutures in the pilot study. Of the grafts in the subsequent 13 patients, 2 patients experienced superficial necrosis with subsequent healing and a good cosmetic outcome, the remainder healed in place without complications, with excellent cosmetic outcome. CONCLUSION: NBCA is suitable for securing selected FTSG and provides a significant time-saving over the traditional approach of suturing such grafts into place.