[Replacement of Kathon CG by Euxyl K 400 in cosmetics; from the frying pan into the fire?]. / Vervangen van Kathon CG in cosmetica door Euxyl K 400; van de regen in de drup?

The recent negative publicity on the cosmetics preservative Kathon CG has made many cosmetic manufacturers look for safer alternatives. The most popular substitute appears to be Euxyl K 400, containing phenoxyethanol and methyldibromoglutaronitrile. Unfortunately, this preservative also induces allergic reactions to cosmetics and (at least in the Netherlands) to 'moist toilet paper'. Therefore, in cases of apparent reactions to cosmetics and of eczema ani, allergy to methyldibromoglutaronitrile should be suspected. Testing the finished products often results in false-negative reactions, and consequently the allergen (suggested concentration 0.05% in petrolatum) should preferably be tested separately.

[Behçet's disease in a Dutch boy with painful skin lesions]. / De ziekte van Behçet bij een Nederlandse jongen met pijnlijke huidafwijkingen.

A 14-years-old Dutch boy had pain in both calves, recurrent oral ulcers, fever, hoarseness and erythema nodosum-like skin lesions. Laryngoscopic examination revealed a vocal cord ulcer and leukocytoclastic vasculitis was visible in a skin biopsy. Based on the clinical picture, the diagnosis of 'incomplete juvenile Behçet's disease' was established. During treatment with colchicine, genital ulcers developed. These disappeared after local treatment with corticosteroids. Juvenile Behçet's disease is rare in Western Europe and the diagnosis is often difficult. Diagnostic criteria have been formulated, but in most cases there is a delay before these criteria are fulfilled due to the slow clinical course of the disease. All organ systems may be affected; mucocutaneous and skin lesions are the most frequent manifestations. Therapy depends on the severity and the symptoms of the disease.

Digital photoplethysmography and light reflection rheography. A clinical comparison.

BACKGROUND: Light reflection rheography (LRR) is appropriate for the global assessment of calf-pump insufficiency regardless of whether it is caused by varicosity, the post-phlebitic syndrome, or deep venous thrombosis. The instrument has been increasingly used by many phlebologists. Digital photoplethysmography (D-PPG) is a further development of this well-established LRR. With this D-PPG instrument it is possible, in contrast to LRR, to calibrate the reflected light. OBJECTIVE AND METHODS: To compare the venous refilling times of both the LRR and the D-PPG when measured at the same time on the same leg. We also evaluated the practical use of both instruments. In total we performed 152 simultaneous measurements with both instruments. RESULTS: We found a statistically significant correlation when we compared the venous refilling time of both LRR and D-PPG (r = .664; P < .001). The observed agreement between both instruments for detecting a disturbed venous refilling time (< or = 25 seconds) is 92%. CONCLUSION: Both instruments seems to correlate as has been shown in this and other studies. The D-PPG has the advantage of being more handy. Furthermore the reflected light is calibrated, which enables to compare intra- and interindividual measurements.

Evaluation of the frequency of contact allergic reactions to Kathon CG in the Maastricht area--1987-1990.

In the period 1987-1990, 999 patients suspected of a contact allergy were patch-tested with Kathon CG 100 ppm active ingredients aq. Of these patients, 84 (8.4%) showed a positive reaction (70% females). In 62% of these cases clinical relevance was established. Most of them suffered from contact dermatitis of the face, the hands or the perianal region.

Frequency of false-negative reactions to the fragrance mix.

To estimate the frequency of false-negative reactions to the fragrance mix, the 8 constituents of the mix in concentrations of 5% (2% for cinnamic aldehyde) were added to the European standard series for routine testing. Patients with positive reactions to individual ingredients in the absence of a reaction to the mix were retested with serial dilutions. In a 4-month period, 677 patients were tested. 61 (9%) reacted to the mix and to 1 or more of the ingredients. 4 patients (0.6% of all patients tested and 6.2% of the patients allergic to fragrances) had false-negative reactions to the mix. They were allergic to cinnamic alcohol, geraniol, isoeugenol and oak moss (1 reaction each), in the absence of a reaction to the fragrance mix. It is concluded that the currently used concentration of the mix (8 x 1%) not infrequently results in false-negative reactions, and that further research should be done to overcome this problem.

Methyldibromoglutaronitrile is an important contact allergen in The Netherlands.

From 15 May to 15 December 1994, 2943 patients suspected of having contact dermatitis (1955 women, 988 men) were patch tested with methyldibromoglutaronitrile 0.3%, 0.1% and 0.05% pet. 119 patients (4.0%; women 4.1%, men 3.8%) proved to be allergic. 71% of the reactions were considered to be relevant. In 2/3 of the patients, causative products were cosmetics, in 1/3 moistened toilet tissues. Testing with methyldibromoglutaronitrile at lower concentrations (0.05% and 0.1%) and with commercial allergens (Euxyl K 400 and methyldibromoglutaronitrile, both containing methyldibromoglutaronitrile 0.1%), resulted in a number of false-negative reactions. All preservatives in the European standard series had lower scores than the 4% positive reactions to methyldibromoglutaronitrile (formaldehyde 2.0%, MCI/MI (Kathon CG) 3.2%, parabens 1.0%, quaternium-15 1.3%). It is concluded that methyldibromoglutaronitrile (present in the commercial preservative Euxyl K 400) is an important contact allergen in the Netherlands in cosmetics and moistened toilet tissues. It should be added to cosmetics series and to proctological series. The optimal test concentration is unknow, but may be 0.3% pet. The concentration of 0.1% methyldibromoglutaronitrile in the currently available commercial allergens appears to be too low, resulting in a number of false-negative reactions.