Evaluation of three scoring methods for Fluorescence Optical Imaging in erosive hand osteoarthritis and rheumatoid arthritis.

Objective: Fluorescence Optical Imaging (FOI) demonstrates indocyanine green (ICG)-enhanced microcirculation in wrist and finger joints, as a sign of inflammation. We wanted to assess the reliability of three FOI scoring methods from Berlin, Stockholm, and Copenhagen, to assess the validity of FOI with MRI as reference and to compare enhancement in hand joints in erosive hand osteoarthritis (OA) vs. rheumatoid arthritis (RA). Design: Five readers scored all finger and wrist joints of 26 patients with erosive hand OA and RA on semi-quantitative 0-3 scales using three different FOI scoring methods. To evaluate inter-reader reliability, we calculated the intraclass correlation coefficients (ICC) for sum scores and prevalence and bias adjusted kappa values for ordinal scales (Pabak-OS) on joint level. Enhancement in joint groups in erosive hand OA vs. RA was compared using Mann-Whitney test. Sensitivities and specificities of FOI was calculated with MRI as reference for hand OA patients only. Results: We found moderate to good inter-reader reliability for all FOI scoring methods (Pabak-OS: 0.50-0.78, ICC: 0.43-0.85) and different patterns of enhancement in erosive hand OA vs. RA with significantly more FOI enhancement in DIP joints in erosive hand OA across all methods. With MRI as reference the different FOI scoring methods reached similar sensitivities (63-65%) and specificities (76-91%). Conclusion: FOI enhancement can be measured reliably in erosive hand OA and RA using three different scoring methods. More DIP enhancement in erosive hand OA patients and good agreement with MRI support the diagnostic performance of FOI.

Physiological responses of a juvenile marine estuarine-dependent fish (Family Sparidae) to changing salinity.

Estuaries are subject to high environmental variability coupled to tidal salinity shifts. Under restricted freshwater flow and prolonged drought conditions, salinity may exceed natural ranges and thus organisms may experience stressful hypersaline conditions. This study assessed the physiology of a juvenile marine estuarine-dependent species Rhabdosargus holubi (Family: Sparidae) under changing salinity to determine the impact on respiration and survival under shock and acclimatisation exposures. Oxygen consumption was not significantly different in the 2.5 to 45 salinity range and the interaction between temperature and salinity was not significant at the moderate levels tested. This confirmed the strong osmoregulatory capabilities of marine estuarine-dependent R. holubi. However, respiration was impacted at salinities of 55-62.5. The salinity tolerance ranges of R. holubi were expanded beyond those previously observed in the laboratory, to a maximum of 77 when fish were gradually exposed to daily 20% incremental changes. This indicated the ability to adapt to hypersaline conditions that occur gradually in anthropogenically altered estuaries which is an important aspect for management decisions regarding freshwater inputs. The adaptability of Rhabdosargus holubi to hypersaline conditions in estuaries may thereby ensure the maintenance of populations in the short term under certain environmental conditions, such as those currently occurring in a freshwater-scarce South Africa. However, in the long term and at more extreme salinities (> 55), the physiology of R. holubi and similar species may be compromised, thus placing the species at risk.