High-performance liquid chromatography (HPLC) as a means of assessing the presence of uric acid in archeological human remains: Challenges and future directions.

OBJECTIVES: This research aimed to replicate the Swinson, D., Snaith, J., Buckberry, J., & Brickley, M. (2010). High performance liquid chromatography (HPLC) in the investigation of gout in paleopathology. International Journal of Osteoarchaeology, 20, 135-143. https://doi.org/10.1002/oa.1009 method for detecting uric acid in archeological human remains to investigate gout in past populations and to improve the original High Performance Liquid Chromatography-ultraviolet (HPLC-UV) method by using HPLC-mass spectrometry (HPLC-MS), a more sensitive, compound-specific detection method. MATERIALS AND METHODS: We used reference samples of uric acid to create a dilution series to assess the limits of quantification and detection. Samples from individuals with and without gout lesions were taken from foot bones and ribs from the English cemeteries of Tanyard, Hickleton, Gloucester, and Lincoln. RESULTS: We could not replicate the results of Swinson and colleagues using HPLC-UV. Tests using a dilution series of uric acid showed HPLC-MS was approximately 100× more sensitive than HPLC-UV, with the additional benefit of being compound specific. A newly developed hydrophilic interaction chromatography (HILIC) method improved retention characteristics. Fourteen samples from eight individuals, five with skeletal lesions consistent with gout, were analyzed with the final method. None showed evidence of uric acid despite the newly developed method's improved sensitivity and specificity. DISCUSSION: The lack of detectable uric acid extracted from these samples suggests that (1) urate crystals were not present in any of the bone samples, regardless of gout status; (2) urate crystals did not survive these specific archeological conditions; or (3) the concentration of uric acid in our bone extracts was low, and thus larger samples would be required.

Patterns of pain in Paget's disease of bone and their outcomes on treatment with pamidronate.

Two-thirds of patients with Paget's disease seeking medical attention present with pain. We studied patterns of pagetic pain in relation to physical activity, and the effect of coexistent osteoarthritis (OA)/pagetic arthropathy on pain and physical activity before and after treatment with pamidronate. Patients with lower-segment Paget's disease (lumbar spine, pelvis or lower limbs), raised alkaline phosphatase (ALP), and pain as a symptom were included. Two subgroups were identified based on the absence (P group), or presence (POA group) of radiological OA in the lower segment. They received 2-4 fortnightly infusions of pamidronate 30-60 mg and were followed up at 6 weeks, 3 months and 6 months. Outcome measures were visual analog scales for pain at rest, on standing, on walking and at night; standing time, walking distance, 50-yard walking time, and ALP. Twenty-five patients (12 men, 13 women, mean age 70.1+/-1.9 years), received a mean of 142+/-9.7 mg of pamidronate. The P group had higher mean ALP (p=0.003) and higher scores for pain (not significant) at baseline than the POA group. Compared to baseline, P group had significant improvements (p<0.01) at 6 months in rest pain, standing pain and walking pain. The POA group had non-significant changes in pain at 6 months. ALP improved significantly at 6 months in both subgroups (p<0.01). The whole group also improved at 6 months in standing time (55.7%, not significant), walking distance (33.9%, not significant), and 50-yard walking time (24.2%, p<0.05). Paget's patients with coexistent joint disease had less severe pain and bone disease at baseline than those without coexistent joint disease, and responded less well to pamidronate, although they did have significant improvement in ALP levels. Radiographic assessment for coexisting joint disease prior to treatment might improve prognostication from the patient's point of view, and improve treatment compliance.