Drug interactions and adverse events associated with antimycotic drugs used for invasive aspergillosis in hematopoietic SCT.

The aim of this study was to assess the frequency of potential drug-drug interactions (pDDIs) and adverse drug events (ADEs) associated with antimycotics in hospitalized patients with hematopoietic SCT (HSCT). Of the 120 HSCT recipients evaluated, 36 received antimycotics. A total of 124 ADEs were recorded in 32 of the 36 patients treated, with 54 ADEs being possibly and 9 probably related to antimycotics. Of the treatments with amphotericin B, 93% were associated with one or more possible and 36% with probable ADEs. The corresponding figures for lipid-based amphotericin B were 100% and 7%, for voriconazole 68% and 11% and for caspofungin 70% and 0%. A total of 57 potentially severe DDIs associated with antimycotics were detected in 31 of the 36 patients. Of these, 14 DDIs were a possible cause of an ADE and 5 (4 times a combination of voriconazole with CYA and once a combination of CYA with conventional amphotericin B) were probably related. Although the prevalence of pDDIs and ADEs is high in HSCT patients, ADEs related with a high probability to treatment with antimycotics are rare. Regarding the high prevalence of pDDIs, our findings underscore the importance of close monitoring of laboratory and clinical parameters, as well as dose adjustment for critical drugs, in patients with HSCT.

[Subtherapeutic blood levels of phenytoin due to a medication error]. / Subtherapeutische Phenytoinspiegel infolge eines Medikationsfehlers.

We report a female patient who was admitted to the emergency ward with suspected cerebral ischemia and in whom transvenous clot lysis was performed. Following lysis the patient developed recurrent complex partial seizures and treatment with intravenous phenytoin was started. Initial phenytoin serum levels were within the therapeutic range. During the course of the in-hospital treatment a sudden fall of phenytoin serum levels was detected and could not be explained by pharmacokinetic changes. Only when the drug application process was further analysed the reason for the fall in serum levels became obvious. Phenytoin sodium injections had not been administered directly into the veins but had been diluted in 0.9% saline infusions. As a result phenytoin sodium injections precipitated and were retained by the particle filter, thus leading to subtherapeutic phenytoin serum levels.

[Minocycline-induced lupus erythematodes]. / Minocyclin-induzierter Lupus erythematodes.

We report the case of an 18-year-old woman with arthralgia and swelling of distal joints at hands and feet, photosensitive reaction, butterfly rash, fatigue, tachypnea and unspecific cardiac pain three months after beginning a treatment with minocycline for acne. Recurrence of symptoms at a higher intensity occurred within hours of reexposition with minocycline. The antinuclear antibody test was positive. After withdrawal of minocycline, the symptoms improved and minocycline-induced lupus was diagnosed. In the Swissmedic and WHO adverse drug reaction databases 267 other cases of possible minocycline-induced lupus were identified. Typical clinical and laboratory features are arthralgia, arthritis, myalgia, increased transaminases and/or jaundice, unspecific symptoms like fatigue and fever, skin disorders and positive antinuclear antibodies.