Epikutantestfehler beim Kobaltchlorid
| Autor: | B. M. Hausen, Bernadette Schubert |
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| Rok vydání: | 2002 |
| Předmět: | |
| Zdroj: | Aktuelle Dermatologie. 28:410-414 |
| ISSN: | 1438-938X 0340-2541 |
| Popis: | Occasionally 24-hour-readings of test reactions from cobalt chloride will show several reddish spots, which resemble petechiae. After 72 hours they have fainted exhibiting a more red-brown color. Only non-sensitized individuals are involved. These skin lesions develop a few weeks or months after the syringe, containing cobalt chloride 1 % in petrolatum, has been used for the first time. Histologically a superficial spongiotic dermatitis shows up correlated with necrosis of the keratinocytes and a reactive hypergranulosis corresponding with a toxic-irritant dermatitis. Reviewing the contents of the used syringes under the microscope reveals the presence of longish crystals of cobalt chloride agglomerated to a prickly mass. In comparison with an unused syringe these crystals are very small, angular and concentrated in flat rings. Homogenizing of the content of a used syringe by help of a tripple roller mill leads to crushing of the crystals. Red ribbon-like stripes are seen during the first passage through the ceramic rollers. After the fifth passage the syringe content is completely rehomogenized and can be used for patch tests as previously. The above described phenomenon has disappeared, but will recur after weeks to months depending on storage habits of the allergy department. In case of frequent changes between warm places and refrigerator the phenomenon will develop within five to seven weeks. Storage under constant temperature will slow down its occurrence to several months or half a year. False reading of cobalt chloride test reactions thus can be avoided either by better storage conditions or by use of a tripple roller mill in the laboratory. |
| Databáze: | OpenAIRE |
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