Meningococcal Disease in Northern Ireland - Past, Present & Future: MeningoNI Forum.

Meningococcal disease has had devastating consequences in Northern Ireland since its first description locally in 1859. The incidence of this disease has significantly declined in recent years, however it is important to understand reasons for this changing epidemiology and to acknowledge the diagnostic and clinical management developments that have been made locally. This review aims to examine the changing face of this disease in Northern Ireland over the years, with particular reference to local disease prevention, epidemiology, diagnosis, clinical treatment and management, post-disease sequelae and the role of meningitis charities locally, in terms of patient support and research.

Improved high-performance liquid chromatography determination of methotrexate and its major metabolite in plasma using a poly(styrene-divinylbenzene) column.

A sensitive high-performance liquid chromatographic assay has been developed for measuring plasma concentrations of methotrexate and its major metabolite, 7-hydroxymethotrexate. Methotrexate and metabolite were extracted from plasma using solid-phase extraction. An internal standard, aminopterin was used. Chromatographic separation was achieved using a 15-cm poly(styrene-divinylbenzene) (PRP-1) column. This column is more robust than a silica-based stationary phase. Post column, the eluent was irradiated with UV light, producing fluorescent photolytic degradation products of methotrexate and the metabolite. The excitation and emission wavelengths of fluorescence detection were at 350 and 435 nm, respectively. The mobile phase consisted of 0.1 M phosphate buffer (pH 6.5), with 6% N,N-dimethylformamide and 0.2% of 30% hydrogen peroxide. The absolute recoveries for methotrexate and 7-hydroxymethotrexate were greater than 86%. Precision, expressed as a coefficient of variation (n=6), was <10% at each of five methotrexate concentrations in the range 2.5-50 ng/ml. The limits of quantitation of methotrexate were 1 and 2.5 ng/ml for methotrexate and 7-hydroxymethotrexate, respectively (using 1 ml plasma). A robust HPLC method has been developed for the reproducible quantitation of methotrexate in plasma of patients taking a weekly dose of methotrexate for rheumatoid arthritis.