Contact dermatitis to rhodium

Abstract

Illpreservatives senes, and the eye drops revealed a strong positive reactiOn to Visum1dnatic fenilefnna® eye drops, wh1ch had been used at the time of the first ophthalmic exammatwn. These eye drops contam: trop1cam1de 0.5%, phenylephrme hydrochlonde 10%, sodium metab1sulfite 0.1 %, thwmersal 0.01% and water.The patch tests w1th these compounds revealed a strong positive reactiOn to phenylephnne hydrochlonde 5% pet. (supplied by Firma Diagent, Florence, Italy). Discuss1onWe report th1s case to pomt out the Importance of patch testmg all patients w1th conJunctiVItiS when the condition does not Improve desp1te correct ophthalmologic prescnptwn.When an ophthamologist suspects an allergrc reaction, he usually elimmates the offending drug and switches to another without performmg a diagnostic patch test. The nsk IS clearly demonstrated m our case, where one of the eye drops prescribed to cure the condition actually contamed the responsible allergen at low concentration, and was the cause of the progressiOn of contact dermatitis.Although It would appear that contact dermatitis to phenylephrme IS rare, no studies exist utilizmg patch tests for diagnostic purposes with phenylephnne-contammg eye drops on patients with ophthalmological disturbances after pupillary dilatation. Although the correct phenylephrme concentration for patch test purposes needs to be assessed, m our case, th1s drug provided a positive patch test reaction at 5% pet. MathiaS et aL (1) only obtamed a pos1t1ve reactwn usmg a 10% aq. solutwn, whereas the 5% and 1% concentratiOns gave negative results. Our case mdicates that close cooperation between ophthalmologist and dermatologist 1s reqmred when an allergic reaction to eye drops IS suspected.Rhodium IS a metal belongmg to the platmum group and the ruthemum tnad: density 12.4, atom1c werght 102.94, atomic number 45. It rs extracted from natural platinum and denves 1ts name from the pmk colour of some of 1ts compounds. It has a very h1gh melting pomt (1966°C) and IS res1stant to aqua reg1a and oxrdiser meltmg. Industnally, rhodium IS used m an alloy with platinum for thermocouples, as a catalyst m the mtrogen oxide combustion of ammoma, and for the rhodium plating of metals (e.g., silver). In the jewelry trade, a rhodium salt (usually hexachlororhodiate) 1s used to sandwrch 2 different metals together m an electrogalvamc bath. It IS also of mterest to allergologists, smce It IS one of the few metals considered safe, no cases of sensrtisation havmg been reported. Indeed, certam precwus metals (e.g., silver) are rhodium-plated so that they can be used by people sens1tised to mckel and cobalt. Case ReportA 47-year-old goldsmith cleaned and degreased preces of metal and rhodium-plated them m an electrogalvamc bath usmg a hexachlororhodiate solution. For about a year, he had had dermatitis on the s1des and back of h1s fingers and on the front of his wnsts. The dermatitis was chrome and recurrent, Improvmg when he was off work.Standard ICDRG patch tests and 0.1% gold chlonde m water, 0. I% hexachlororhodiat...

Platinum‐Group Metals

“…20.9: Selected data on the toxicity of PGM compounds (data from Moore et al 1975;IPCS 1991;Marquardt and Schäfer 1994 mostly combined reactions with other metals, primarily nickel, have been observed. There are also indications for a potential allergenicity of Rh (Bedello et al 1987; de la Cuadra and Grau Massanes 1991), but to date only a few case studies have been reported (Gebel 2000). Care must be taken when handling volatile compounds such as osmium OsO 4 and RuO 4 .…”

Occupational immediate‐type asthma and rhinitis due to rhodium salts

“…Occupational allergic contact dermatitis has been described in subjects working in the jewelry trade [Bedello et al, 1987;De la Cuadra and Grau-Massanés, 1991;De la Fuente et al, 2003], but there are no cases with immediatetype allergic asthma due to rhodium salts in the literature. The impact of rhodium salt sensitization in workers of precious metals refineries remains unknown, but it is likely that platinum salts are the primary allergen in these settings.…”

Contact sensitization to nickel from rhodium‐plated ‘nickel‐free’ earrings

“…In this last application, it is mostly present in objects containing silver, white gold or platinum, owing to its silvery white colour. Rhodium is generally regarded as allergologically safe; however, there are a few reports of occupational contact dermatitis (1–3) and of contact sensitization related to the use of dental prostheses (4). , Our patient developed nickel allergy after having used a new pair of clip‐on earrings which were labelled as ‘hypoallergenic’ and ‘nickel‐free’.…”