Evaluation of an oral sodium bicarbonate protocol for high-dose methotrexate urine alkalinization.

PURPOSE: Intravenous (IV) sodium bicarbonate is considered standard therapy for high-dose methotrexate (HDMTX) urine alkalinization. Due to a national IV sodium bicarbonate shortage, an oral (PO) sodium bicarbonate protocol was implemented by Alberta Health Services (AHS) for HDMTX urine alkalinization. This study aims to evaluate the efficacy and safety of the PO sodium bicarbonate protocol compared to IV sodium bicarbonate for HDMTX urine alkalinization. METHODS: A retrospective chart review of adult patients who received HDMTX (> 500 mg/m2) with sodium bicarbonate for urine alkalinization at 4 hospitals in Alberta was conducted. Patients who received IV sodium bicarbonate between January and June 2017 and PO sodium bicarbonate between July and December 2017 were compared for the primary outcome of time to methotrexate clearance. RESULTS: A total of 84 and 78 HDMTX cycles were included in the IV and PO cohorts, respectively. No difference in time to methotrexate clearance was seen between the IV and PO cohorts, 91.6 (± 35.4) hours and 95.2 (± 44) hours respectively; p = 0.5. The proportion of HDMTX cycles that experienced a > 25% increase in serum creatinine was not statistically significant, IV protocol 12% and PO protocol 5%; p = 0.13. Nausea and emesis occurred more frequently in the PO cohort than the IV cohort, though rarely resulted in refused doses or change to alternate sodium bicarbonate formulations. CONCLUSIONS: The results of this study indicate that the AHS PO sodium bicarbonate protocol was no different in time to methotrexate clearance or rates of increased serum creatinine when compared to IV sodium bicarbonate.

Metabolic analysis of knee synovial fluid as a potential diagnostic approach for osteoarthritis.

Osteoarthritis (OA) is a leading cause of chronic joint pain in the older human population. Diagnosis of OA at an earlier stage may enable the development of new treatments to one day effectively modify the progression and prognosis of the disease. In this work, we explore whether an integrated metabolomics approach could be utilized for the diagnosis of OA. Synovial fluid (SF) samples were collected from symptomatic chronic knee OA patients and normal human cadaveric knee joints. The samples were analyzed using (1)H nuclear magnetic resonance (NMR) spectroscopy and gas chromatography-mass spectrometry (GC-MS) followed by multivariate statistical analysis. Based on the metabolic profiles, we were able to distinguish OA patients from the controls and validate the statistical models. Moreover, we have integrated the (1)H NMR and GC-MS results and we found that 11 metabolites were statistically important for the separation between OA and normal SF. Additionally, statistical analysis showed an excellent predictive ability of the constructed metabolomics model (area under the receiver operating characteristic curve = 1.0). Our findings indicate that metabolomics might serve as a promising approach for the diagnosis and prognosis of degenerative changes in the knee joint and should be further validated in clinical settings.