Patient-ready syringes containing 25 mg/mL methotrexate can be kept at temperature ranging from 4 °C to 37 °C for up to 12 weeks for use in psoriatic and rheumatologic conditions.

BACKGROUND: Methotrexate (MTX) is a mainstay drug in the treatment of psoriatic and rheumatologic conditions. Subcutaneous MTX has become a feasible treatment alternative with the development of prefilled syringes or autoinjectors containing MTX solution that can be self-administered by the patient at home. However, MTX prefilled auto-injector pens are still not available in some countries. OBJECTIVE: This study aimed to investigate the stability and sterility of 25 mg/mL MTX solution in a disposable plastic syringe over a 12-week period under light protection at temperatures of 4 °C, 25 °C, and 37 °C. METHODS: This study was conducted during November 2019 to February 2020 at the Faculty of Medicine Siriraj Hospital, Mahidol University. Stability was evaluated using ultra-high-performance liquid chromatography technique, and sterility was assessed by cultures for bacterial and fungal contamination. RESULTS: Our results revealed that patient-ready syringes containing 25 mg/mL MTX solution can be prepared in advance and kept for up to 12 weeks under light protection, and they can be kept at temperatures ranging from 4 to 37 °C. CONCLUSION: This system for delivering MTX to patients that are refractory to or intolerant of oral MTX via a self-administered pre-filled syringe is both efficient and easy to implement in care settings where commercially alternatives are not yet available.

Severe anaphylaxis after pelvic examination: a case report of dual latex and chlorhexidine allergies.

BACKGROUND: Natural rubber latex and chlorhexidine have previously been identified as causative substances in perioperative anaphylaxis. A pelvic examinations is generally considered noninvasive, however, this procedure is rarely associated with severe allergic reactions. We reported a rare case of dual latex and chlorhexidine allergies which caused anaphylaxis after pelvic examination in a woman with a history of latex-related fruits allergy. CASE PRESENTATION: A 54-year-old woman had severe anaphylaxis after a pelvic examination due to dual latex and chlorhexidine (CHX) allergies. The gynecologist used CHX for the vaginal preparation and wore latex-containing gloves with lubricating gel during the examination. In vivo and in vitro tests revealed CHX sensitization by a positive skin prick test to chlorhexidine at a very low concentration (0.002 mg/mL), and a positive basophil activation test to CHX. Latex allergy was confirmed by a positive specific IgE to latex and a positive glove-use test at 20 min. An analysis of specific IgE to latex component revealed positive results for Hev b 1, 5, 6.02, and 11. As she also had a past history of fruit allergy, prick-to-prick testing with latex-related fruits was performed. The results were positive for avocado, banana, jackfruit, kiwi, and longan. CONCLUSIONS: Concomitant mucosal exposure of both natural rubber latex and CHX in highly sensitized patients during pelvic examinations can lead to severe anaphylaxis. Pre-procedural screening for an allergy to latex or CHX, or to any other allergen, should be performed in patients where there is suspicion of a specific allergy due to a previous allergic reaction. Increased awareness of these two allergens in all healthcare settings may improve patient safety.