Sanami Takahashi

INTERLEUKIN-6 (IL-6) IN PATIENTS WITH BEHCET'S DISEASE

We have examined the levels of interleukin-6 (IL-6) in plasma and supernatants of peripheral blood mononuclear cells (PBMC) from patients with Behçets disease and healthy controls using a sensitive enzyme-linked immunosorbent assay (ELISA). Plasma IL-6 level was not detected in any subjects. The IL-6 concentrations in culture supernatants of patients with active Behçets disease were significantly high compared with patients with inactive disease and healthy controls. Moreover, we investigated IL-6 gene expression in cultured PBMC from patients with Behçets disease. IL-6 gene expression was enhanced in active patients compared with inactive patients. These results show that IL-6 may play a role in the pathogenesis of Behçets disease.

Contact urticaria syndrome caused by patch testing with cefotiam hydrochloride.

Comment Isopropanolamine (CAS 78-96-6) is a buffering agent used in cosmetics, particularly gels, and in hair perms, hair sprays and tanning lotions (1). It has not previously been known to cause allergic contact dermatitis. Topical non-steroidal anti-inflammatory preparations are a wellestablished cause of contact allergy, photoallergy and phototoxicity (2), usually due to the active component rather than the vehicle. In Austria, the sensitization rate to bufexamac has been estimated at 4%, leading to suggestion for inclusion in the standard series (3). We considered the possibility that the patch test reaction to isopropanolamine was irritant, though its morphology and timing were more consistent with an allergic reaction. Patch testing 22 patients as controls, with isopropanolamine 1% aq., resulted in a slight irri-

Low Expression of Adhesion Molecules in a Case of Cutaneous T-cell Lymphoma

A case of cutaneous T‐cell lymphoma (CTCL) with low expression of the adhesion molecules lymphocyte function‐associated antigen‐1 (LFA‐1), intercellular adhesion molecule‐1 (ICAM‐1), and very late antigen‐4 (VLA‐4) is described. The patient was a 90‐year‐old man with red round homogeneous tumors on his scalp, trunk, and extremities. He had no history of definite erythema or plaque stage. A biopsy sample taken from a tumor revealed massive infiltration of atypical lymphocytes in the reticular dermis and subcutis with a definite clear zone. The atypical lymphocytes were medium‐sized with slightly convoluted nuclei. Immunohistochemically, the infiltrates showed the phenotype of so‐called memory T cells. On the basis of these features, the case was diagnosed as CTCL. Expression of LFA‐1, ICAM‐1 and VLA‐4 on the infiltrates was 9%, 13% and 11%, respectively, which is much lower than that in classic mycosis fungoides. This finding suggests that loss of these adhesion molecules may contribute to loss of epidermotropism in the advanced stage of CTCL.

Allergic contact dermatitis caused by diethyl thiourea in a neoprene-containing wet suit

Dear Editor, Neoprene, which is a synthetic polychloroprene-based rubber made by polymerization of chloroprene, is widely used in many goods such as sports items, gloves, shoes and orthopedic devices. Neoprene contains numerous sensitizing additives including vulcanization accelerators such as thiourea compounds. Some cases have been reported to have allergic contact dermatitis due to neoprene, but no case diagnosed by patch testing in Japan has been published. We report the first case of allergic contact dermatitis (ACD) due to diethyl thiourea (DETU) in a neoprene-containing product in Japan. A 53-year-old man developed an itchy erythematous eruption, confined to the skin under his neoprene wet suit 1 h after he had taken off the suit. He had worn a wet suit for 3–4 h for water sports. Two months after the incident, he consulted our hospital to have the allergen of his eruption investigated. He had no history of atopic dermatitis or other allergic disorders. The patient was patch tested with the six wet suit materials of neoprene and a lining material, a Japanese standard series of allergens including p-tert-butylphenol formaldehyde resin (PTBP-FR), a rubber chemical series (including DETU, diphenyl thiourea [DPTU] and dibutyl thiourea [DBTU]) and a plastic series. Patch testing was performed using a patch tester (Torii Pharmaceutical, Tokyo, Japan) applied to the patient’s back for 48 h. Results were evaluated according to International Contact Dermatitis Research Group guidelines. At 48 and 72 h, positive reactions to materials of neoprene and DETU (1% pet.) were observed (Table 1, Fig. S1). All positive products of neoprene contained DETU. Our final diagnosis was ACD due to DETU in neoprene. Some cases of ACD caused by neoprene have been reported previously. The main contact sensitizers in neoprene products are thiourea derivatives. Recently, several cases of ACD due to PTBP-FR in neoprene products have been reported. There have also been reports of ACD from colophonium, zinc diethyl dithiocarbamate and nickel in neoprene products, as rare cases. Thioureas include DETU, DPTU, DBTU and ethylenethiourea. They are used mainly as accelerators in the rubber industry. Thioureas are also found in polyvinyl chloride adhesive tapes, diazo paper, glue removers, fungicides and pesticides. A positive patch test reaction to the thiourea mixture was noted in 0.39% of Finnish general dermatology patients with suspected contact dermatitis. A recent study suggested that DETU acts as a prehapten. Ethyl isothiocyanate (EITC) is shown to be continuously produced from DETU in the neoprene materials when they were heated to 37°C for a few hours. Therefore, DETU contained in a neoprene product may easily form the extreme sensitizer EITC at body temperature resulting in contact allergy to EITC. In our case, dermatitis on the skin under the neoprene wet suit and positive reaction of patch testing may be due to EITC produced during skin contact. ACD from thioureas may be underdiagnosed in Japan, as they are not tested as part of the Japanese standard patch test series. Patients suspected of ACD from neoprene need to be patch tested with components in neoprene such as thioureas and PTBP-FR.