Erythema histology

Kang et al. [23] compared the clinical, histologic, and molecular responses of normal human skin to topical retinol with that of retinoic acid. Application of retinol and retinoic acid produced epidermal thickening. However, retinol produced less erythema compared with retinoic acid. The authors suggest that these data are compatible with the idea that retinol may he a pro-hormone of retinoic acid. 

A 39-year-old woman with rheumatoid arthritis took hydroxychloroquine 200 mg bd for painful synovitis, in addition to meloxicam, co-dydramol, and Gaviscon. She inadvertently took twice the prescribed dose of hydroxychloroquine, but stopped it after 2 weeks because of nausea. The next day she developed a widespread blotchy erythema and 2 weeks later was admitted to hospital with clinical and histological toxic epidermal necrolysis and deteriorated rapidly with multiorgan failure she died 1 week later. 

Diffuse maculopapular erythema with histological features consisting of epidermal spongiosis and interstitial mixed inflammatory cell infiltrate was reported in one patient, and a causal role was suggested by the recurrence of symptoms after interleukin-6 re-administration (SEDA-19, 341). 

A 68-year-old man who had taken lisinopril 10 mg/day for several years stopped taking it temporarily because of a cough. It was then restarted in a dosage of 5 mg/day and a few days later he developed several bean-sized non-pruritic erythematous plaques with scales over the whole body, particularly on the chest. The appearance was of seborrheic dermatitis, but histology showed the features of erythema multiforme. The eruptions cleared completely a few days after lisinopril withdrawal. Two months later, a rechallenge test was positive. 

A 32-year-old HIV-positive man, who had been treated with didanosine and lamivudine, added saquinavir (600 mg tds) because of a rising plasma HIV-1 RNA viral load. Five days later he presented with a generalized maculopapular skin eruption, the lesions being centered on a bulla, and erosive lesions on the palate. Histological examination was compatible with erythema multiforme. Saquinavir was discontinued and all the mucocutaneous lesions healed within 15 days. RechaUenge was not attempted. 

An 86-year-old Japanese man received a pacemaker for atrioventricular block, and 2 months later developed a scaly erythema over the implantation site and later widespread nummular eczema. Histologically, the lesions showed slight spongiosis, intracellular edema, moderate acanthosis in the epidermis, and perivascular infiltration with thickened capillary walls in the dermis. The pacemaker contained titanium and a variety of other metals, but patch tests were all negative. However, titanium sensitivity was demonstrated by intracutaneous and lymphocyte stimulation tests. 

Clinical results appear slowly and gradually, after histological improvement. The skin soon appears to be intensely hydrated, once the erythema has disappeared or subsided. Clinically, it takes a year for the rejuvenating action of tretinoin to show. Patients, who hope to see rapid... 

Skin. The potential to cause skin irritation was investigated in rats, guinea pigs and mice who had 0.1 ml 12.5% CS in either com oil or acetone applied unoccluded to the shaven dorsal trunk skin for 6 h, and the area subsequently and periodically inspected up to 21 days for local reactions. Erythema was more marked than oedema, and both resolved by 7 days post-application. Histological examination of skin biopsies taken from a few animals at 3 days after CS application showed foci of epidermal necrosis in the contaminated area with spongiosis and acute inflammatory infiltration of the outer dermis (Ballantyne and Swanston, 1978). 

Eczema. A dermatitis characterized by non-contagious inflammation of skin with typical clinical (itch, erythema, papules, seropapules, vesicles, squames, crusts, lichenification) and dermato-histological (spongiosis, acanthosis, parakeratosis, lymphocytic infiltration) findings. Often due to sensitization. 

Drug-induced erythema multiforme is histologically and even clinically related to fixed drug eruptions. There also seems to be some relationship to Lyell s syndrome, as transitional cases have been observed (Schuppli 1972). 

The histological and electron-microscopic findings of Lyell s syndrome are highly characteristic and serve to differentiate it from other bullous skin reactions such as Stevens-Johnson syndrome and erythema multiforme (Braun-Falco and Bandmann 1970). 

Endoscopy is helpful for the diagnosis of PMC by showing typical raised yeilowish-TAhite plaques separated by areas of normal mucosa, oedema or erythema (MEGiBOwet al. 1984). The plaques usually have a thickness of 2-10 mm. These plaques can be larger,extended, and are adherent to the mucosa (Ros et aL 1996). Epithelial necrosis, infiltration of the lamina propria with polymorphonuclear cells, and eosinophilic exudates are histologically demonstrated. The "pseudomembrane is composed of cellular debris, fibrin, mucous, and polymorphonuclear cells (Hamrick et al. 1989). 

If pure CA is applied to the nipple or to the flank of an unsensitized guinea pig, an erythema and edema appear at the site of the test. After 14 hours the histological examination shows epidermal lesions (vesicles, detachement of the epidermis, epidermal necrosis) and a dermal infiltrate which is partially composed of eosinophils which invade the epidermis. 

The epidermis is normal or shows mild spongiosis with upper dermal edema and perivascular lymphohistiocy-tic infiltrate. Vacuolar degeneration of the basal cells is occasionally present. The classical features of erythema-multiforme are absent. The morphology, clinical course and histology of the eruptions are not characteristic of classical erythema multiforme. 

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