8 November 2021

Day 2 conference highlights

ACR COVID-19 Giant-cell arteritis Lupus Technology

Today our early career reporters cover SLE and HCQ reduction, machine learning in diagnostics, covid in rheuma patients and GCA fast track clinic.

Dr Chris McMaster

Don’t stop hydroxychloroquine if you don’t have to.

That’s my take home message from day 2 of ACR 2021. Professor Sasha Bernatsky spoke about her study prospectively evaluating SLE flare risk among SLICC cohort patients whose hydroxychloroquine was either stopped or the dose reduced (plenary session #0959).

While the outcome was predictable – less hydroxychloroquine means more flares – I think it will be very useful in clinical practice. The temptation to wean therapy in a stable patient is strong and we’re often asked by our patients whether this is safe. We now have clear data to point to, so we can have informed discussions about the risks and benefits.

Back to the geeky side of things, I enjoyed Professor Denis Poddubnyy’s poster (#0905) on a machine learning model to identify inflammatory lesions in sacroiliac joint MRI STIR sequences.

They used a two-step approach, first training a model to separate the sacroiliac joints from the rest of the image, then another model to identify bone marrow oedema in the SIJs.

This has exciting implications for two reasons: 1) standardisation of MRI reading by neural network models might help to reduce the variability of interpretation that has plagued SIJ MRI; and 2) as Dr Maureen Dubreuil suggested in the chat, there is potentially some knowledge to be gained by looking at the images misclassified by the model – perhaps it is seeing something that we missed entirely.

Watch this space, because it might end up being one of the first machine learning algorithms to make its way into rheumatology practice.

  • 0959 Impact of Systemic Lupus Disease Activity State on Flare Risk After Hydroxychloroquine Maintenance, Reduction or Discontinuation in a Multinational Inception Cohort
  • 0905 Artificial Neural Network for the Recognition of Active Inflammatory Changes Compatible with Axial Spondyloarthritis on Magnetic Resonance Imaging of Sacroiliac Joints

Dr Chris McMaster is a Melbourne-based final-year rheumatology and clinical pharmacology trainee.

Dr Bonnia Liu

Day 2 and I’m all about Covid today!

Dr Arielle Mendel (Oral #0962) found that 43% of Covid-positive patients were positive for antiphospholipid antibodies compared to 32% of non-Covid patients. The presence of anticardiolipin IgM and IgG were independently associated with increased risk of ICU stay and mechanical ventilation which may help with risk stratification.  

Dr Sebastian Sattui (Oral #0952) identified risks factors associated with poor outcomes in patients with GCA, AAV and PMR. PMR patients had better outcomes compared to GCA despite sharing similar patient characteristics. Of note, diagnosis between October 2020 and April 2021 was associated with lower risk severe disease compared to the proceeding 6 months. Possibly attributed to better treatment options and vaccine roll out.

The importance of vaccine response was illustrated by Dr Andrew Laster (Oral #0963) who reported on bDMARDs and csDMARDs and their effects on covid vaccine immunogenicity. Rituximab and abatacept IV resulted in a blunted antibody response, as did methotrexate and mycophenolate.

Dr Samuel Bitoun (Oral #0964) goes on to elaborate patients receiving rituximab within the last 6 months had a lower response rate to the vaccine attributed to blunted B-cell response, however T-cell response remains intact. Thus, we should still persist with vaccines regardless of rituximab.

  • 0962 Association of Antiphospholipid Antibodies with Thromboembolic Events and Severe Outcomes in COVID-19
  • 0952 Outcomes of COVID-19 Infection in Patients with Primary Systemic Vasculitis and Polymyalgia Rheumatica: Results from the COVID-19 Global Rheumatology Alliance Physician Registry
  • 0963 Immunogenicity of COVID-19 Vaccines in Patients with Autoimmune and Inflammatory Rheumatic Diseases (AIIRDs)
  • 0964 Rituximab Treatment Dramatically Reduces Neutralizing Humoral Response to mRNA SARS-COV-2 Vaccines in Patients with Autoimmune Diseases

Dr Bonnia Liu is a final year rheumatology trainee pursuing dual training in rheumatology and nuclear medicine at Austin Hospital in Melbourne.

Dr Kylan Pathmanathan

At the time of referral, the diagnosis and exclusion of giant cell arteritis (GCA) is fraught with difficulty.

I’m sure I’m not the only rheumatology registrar to admit difficulty when triaging cases over the phone. GCA fast track clinics have been developed to swiftly review and investigate, but also promptly de-escalate steroid therapy when applicable.

A valuable pathway? Absolutely. A rapid access headache clinic? Not exactly the intention.

Dr Mmoloki Mathake and colleagues evaluated the Southend pre-test probability score in an Australian GCA fast track clinic at Royal Perth Hospital (poster #0652). The score was applied retrospectively to 104 referred cases and classified patients into low, medium and high risk for GCA. The tool was found to have a sensitivity of 100%, specificity of 57% and negative predictive value of 100%.

Notable caveats include that the tool was based on a rheumatologist’s initial assessment rather than a GP’s referral information. Additionally, the tool was applied retrospectively rather than prospectively.

Nonetheless, the concept and its relevance in an Australian setting is important. It has the potential to aid clinicians in excluding GCA while focusing resources on prompt investigation and diagnosis of GCA in the remaining cases.

  • 0652 Application of a GCA Probability Score to Patients Referred to a GCA Fast Track Clinic

Dr Kylan Pathmanathan is an advanced trainee in rheumatology based in Perth.

ICYMI

Catch up with the day 1 highlights