[Drug exanthema in connection with trimethoprim and sulfamethoxazole treatment, triggered by leech therapy]. / Arzneimittelexanthem in Zusammenhang mit Trimethoprim- und Sulfamethoxazol-Medikation -- Blutegeltherapie als triggernder Faktor.

In a 58-year-old hospitalized woman with gonarthrosis a leech therapy was applied to both knee joints. In the evening of the following day she observed strong pruritus in the area of the leech bites; in addition a maculopapular exanthema appeared on the torso and her lower extremities. The allergic reaction lasted four days. Administration of antihistamines only led to a slight improvement of the symptoms. A full restitution could only be achieved after a systemic dose of glucocorticoids on the fourth day after leech therapy. Eight days before beginning of the leech therapy a five-day antibiotic therapy with trimethoprim and sulfamethoxazole (Cotrim forte) had been administered to treat an uncomplicated urinary infection. Allergic reactions are well-known complications of these antibiotics and of leech therapy. The four-day duration of the allergic reaction after leech therapy, however, was untypical. In order to explain these symptoms, a prick test and an epicutaneous test for the antibiotic components were executed five weeks after the leech therapy. Furthermore, a second leech therapy was administered and a lymphocyte transformation test (LTT) was carried out. The results of the LTT showed a sensitization for sulfamethoxazole and a possible sensitization for trimethoprim, the results of the epicutaneous test showed a positive reaction to sodium lauryl sulfate, a component of the antibiotic. In the area of the leech bites a clear local skin reaction was observed. These results suggest a drug exanthema, in all probability triggered by the leech therapy.

Analysis of the action of the restriction endonuclease AluI using three different comet assay protocols.

BACKGROUND AND PURPOSE: The comet assay offers the opportunity to measure the amount of DNA damage and the effectiveness of DNA repair in single cells. In a first part, experiments are presented comparing three different protocols of the comet assay technique with respect to the analysis of the induction of DNA damage after X-irradiation in isolated human lymphocytes and CHO cells. In a second part, the restriction enzyme AluI, an agent producing DNA double-strand breaks exclusively, was introduced into CHO cells by electroporation and the effects were analyzed using the different comet assay protocols. The experiments were carried out in order to test the assertion that comet assay techniques can measure different types of DNA damages at different pH conditions of lysis and electrophoresis. MATERIAL AND METHODS: Three different comet assay protocols were used for the analysis of DNA damage in lymphocytes and CHO cells. RESULTS: The results clearly indicate that among the three protocols the modified comet assay technique used by the authors showed the highest sensitivity in the radiotherapy-relevant dose range between 0 and 2 Gy. All three protocols were capable of detecting an effect by AluI. This effect, however, was clearly different from radiation effects. Whereas after radiation exposure all cell nuclei show a dose-dependent increase in DNA content in the comet tail, most of the cell nuclei were unaffected by an AluI uptake. Nevertheless, there was an effect by AluI that could be detected in all three assay versions: between 5% and 15% of the nuclei showed clearly abnormal comet morphologies. CONCLUSION: Neither the strictly alkaline nor the strictly neutral comet assay is applicable in the radiation dose range of about 2 Gy. The restriction enzyme results show that other factors than just DNA strand breaks contribute to DNA migration into the tail of the comets.