Identification of a unique anti-Ro60 subset with restricted serological and molecular profiles.

Anti-Ro60 is one of the most common and clinically important serum autoantibodies that has a number of diagnostic and predictive capabilities. Most diagnostic laboratories report this simply as a qualitative positive/negative result. The objective of this study was to examine the clinical and serological relevance of a novel subset of anti-Ro60 in patients who display low levels of anti-Ro60 (anti-Ro60low ). We retrospectively identified anti-Ro60 sera during a 12-month period at a major immunopathology diagnostic laboratory in Australia. These all were anti-Ro60-precipitin-positive on the diagnostic gold standard counter-immuno-electrophoresis (CIEP). Lineblot immunoassay was used to stratify patients into either anti-Ro60low or anti-Ro60high subsets. We compared the medical and laboratory parameters associated with each group. Enzyme-linked immunosorbent assay (ELISA) and mass spectrometry techniques were used to analyse the serological and molecular basis behind the two subsets. Anti-Ro60low patients displayed less serological activity than anti-Ro60high patients with less intermolecular spreading, hypergammaglobulinaemia and less tendency to undergo anti-Ro60 isotype-switching than anti-Ro60high patients. Mass spectrometric typing of the anti-Ro60low subset showed restricted variable heavy chain subfamily usage and amino acid point mutations. This subset also displayed clinical relevance, being present in a number of patients with systemic autoimmune rheumatic diseases (SARD). We identify a novel anti-Ro60low patient subset that is distinct from anti-Ro60high patients serologically and molecularly. It is not clear whether they arise from common or separate origins; however, they probably have different developmental pathways to account for the stark difference in immunological maturity. We hence demonstrate significance to anti-Ro60low and justify accurate detection in the diagnostic laboratory.

Survey of anaesthetists' practice of sedation for gastrointestinal endoscopy.

We conducted a survey of Australian specialist anaesthetists about their practice of sedation for elective and emergency gastroscopy, endoscopic retrograde cholangiopancreatography (ERCP), and colonoscopy. A 24-item survey was emailed to 1,000 anaesthetists in August 2015. Responses were received from 409 anaesthetists (response rate=41%) with responses from 395 anaesthetists analysed. Pulse oximetry and oxygen administration were routine for all procedures for all respondents. Blood pressure was routinely measured by most respondents during gastroscopy (elective=88%; emergency=97%), ERCP (elective=99%; emergency=99%) and colonoscopy (elective=91%; emergency=98%). The airway was routinely managed with jaw lift or oral or nasal airway by 99%, 76% and 97% of respondents during gastroscopy, ERCP and colonoscopy, whereas in emergency procedures endotracheal intubation was routine in 49%, 64% and 17% of procedures. Propofol was routinely administered by 99% of respondents for gastroscopy and 100% of respondents for ERCP and colonoscopy. A maximum depth of sedation in which patients were unresponsive to painful stimulation was targeted by the majority of respondents for all procedures except for elective gastroscopy. These results may be used to facilitate comparison of practice in Australia and overseas, and give an indication of compliance by Australian anaesthetists with the relevant Australian and New Zealand College of Anaesthetists guideline.