Cold urticaria: inhibition of cold-induced histamine release by doxantrazole.

Thirteen patients with cold urticaria were studied to assess the effect of the systemic drug doxantrazole, which has actions resembling disodium cromoglycate, on cold evoked histamine release. The patients, all of whom developed an immediate local whealing response after cooling of the forearm, demonstrated release of histamine into venous blood draining that forearm. Following doxantrazole treatment, significant suppression of histamine release occurred. In some but not all patients this was accompanied by diminution of urtication in response to cooling. A double-blind study was carried out in 3 subjects, all of whom showed diminished cold-stimulated histamine release after doxantrazole. Two of these showed clinical improvement. Doxantrazole had no effect on erythema due to intradermal histamine, but did suppress the erythematous reaction to intradermal injection of compound 48/80. Our results suggest that doxantrazole or related anti-allergic agents might be useful in the treatment of cold urticaria.

The epidermal component of melanocytic naevi.

Two hundred moles were examined histologically and the degree and type of epidermal change was recorded and correlated with the arrangement, density and type of naevus cells present and with the clinical presentation. Resemblances to the epidermal architecture of seborrhoeic warts were noted in 49% of the moles studied (this type of change was mainly seen in younger patients). In these there was a predominance of epithelioid cells, mainly in the junctional and upper dermal zones. Thirty-five per cent of moles possessed an epidermis with an overall appearance of being stretched, beneath which was a relatively clear zone followed by a uniform distribution of predominantly "lymphocytoid" naevus cells and large numbers of naevus cells of the giant type. These were found mainly in the older age groups. A third group (11%) was characterized by the presence of bulbous epidermal rete ridges and many junctional nests of naevus cells. This group was found mainly in younger age groups and there was often a history of recent change in the mole. It is concluded that the epidermal component of moles might itself be a naevoid disorder or result from the dermal disturbance induced by the mole cells.

Mixed connective tissue disease characterized by speckled epidermal nuclear IgG deposition in normal skin.

Four African female patients are described, who presented with the features of systemic sclerosis. Overlapping features of lupus erythematosus or dermatomyositis were present in three cases but were not prominent. Direct immunofluorescence of uninvolved skin revealed a particulate (or speckled) epidermal nuclear staining, with specificity for IgG. In view of the reported association between this finding and mixed connective tissue disease, these patients were treated with corticosteroids and marked improvment occurred in all cases. The usefulness of this investigation in making the distinction between systemic sclerosis and mixed connective tissue disease and in indicating a potentially effective form of therapy is discussed.

The effects of prostaglandins E1 and F2alpha on epidermal growth.

The effects of prostaglandins E1 and F2alpha (PGE1 and PGF2alpha) on the growth of guinea pig epidermis have been studied in vivo. The prostaglandins were injected intradermally into guinea pigs, and tritiated thymidine was injected intraperitoneally prior to sacrifice. The autoradiographic labelling indices (L.I.) were assessed and a significant increase was found 4 h after injection of PGE1 -an effect which lasted for up to 72 h. PGF2alpha injections had no significant effect on the L.I.

Induced tolerance in cold urticaria caused by cold-evoked histamine release.

The interrelations between cold sensitivity and release of histamine and other mediators in five patients with cold urticaria undergoing cold tolerance treatment were studied. Tolerance to cold was produced in all patients by repeated cold exposure. In four patients tolerance was maintained by once daily exposures. In the fifth patient 4-hourly exposures were necessary. Cold sensitivity was associated with histamine release in venous blood draining urticated skin. No prostaglandin activity was detected, and low concentrations of kinin activity were found in blood draining the normal and exposed skin of healthy subjects as well as in patients with cold urticaria. After induction of tolerance, no histamine release occurred on challenge by cold. Relapse of sensitivity was associated with reappearance of histamine release on challenge. The conclusion that tolerance is due to depletion of histamine stores in skin after repeated cold exposure was supported by diminished wealing in response to injection of a histamine liberator (compound 48/80) in cold-tolerant skin.

Pharmacological modulation of neutrophil phagocytic function in a patient with recurrent sepsis, pyoderma gangrenosum and impaired phagocytosis.

A 50-year-old man with recurrent life-threatening sepsis and a cutaneous condition resembling pyoderma gangrenosum, was found to have a defect of neutrophil phagocytic function. Phagocytosis could be enhanced by corticosteroids, both in vitro in a dose-dependent manner, and in vivo, when it was accompanied by rapid clinical improvement. Studies with steroid hormones and immuno-stimulatory drugs are described.