2022 Pre-RNDS | MOG Antibody Disease (MOGAD)

Summary

In this informative lecture, Dr. Michael Levy from Harvard Medical School delves into MOG antibody disease, a demyelinating condition affecting the central nervous system. He explains the discovery and significance of myelin oligodendrocyte glycoprotein, the unique characteristics of the disease, its diagnosis, and the challenges in treatment, highlighting the importance of distinguishing it from other similar conditions like MS and NMO. The talk also covers current treatment strategies, including acute management with steroids and IVIG, and preventive measures, with a focus on emerging therapies targeting IL-6.

Takeaways

• 👩‍⚕️ Michael Levy is an associate professor at Harvard Medical School and a neurologist at Massachusetts General Hospital, discussing MOG antibody disease.
• 🧠 MOG stands for myelin oligodendrocyte glycoprotein, a protein found only in the central nervous system, recognized for its importance since the 1940s.
• 🧪 MOG antibody disease was identified in the 1990s, initially thought to mark MS patients, but now understood as a distinct demyelinating disease.
• 🔬 MOG antibody disease affects a range of patients, including those with optic neuritis, transverse myelitis, and brain lesions.
• 👶 The disease has a bimodal distribution, affecting both children (often with ADEM) and adults (often with optic neuritis or transverse myelitis).
• 🔍 Diagnostic criteria for MOG antibody disease include inflammation in the optic nerve, spinal cord, or brain, and a positive MOG antibody test.
• 💉 Acute treatment involves high-dose steroids, with options like plasma exchange and IVIG for cases that do not respond well to steroids.
• 🧬 Preventive treatments include IVIG, immune suppression drugs like mycophenolate, and experimental approaches like cytokine blockers.
• 📊 Studies have shown varying success rates for different treatments, with IVIG emerging as one of the more effective options.
• 🌍 Ongoing research aims to develop and approve new treatments for MOG antibody disease by 2025, with international clinical trials underway.

Q & A

Who is Michael Levy and what is his professional background?

Michael Levy is an associate professor at Harvard Medical School and a neurologist at Massachusetts General Hospital. He specializes in the study of MOG antibody disease.

What does MOG stand for and where is it found in the body?

MOG stands for myelin oligodendrocyte glycoprotein. It is a protein that is found exclusively in the central nervous system, including the brain, spinal cord, and optic nerves.

How did the discovery of MOG's role in demyelinating diseases come about?

The discovery came about through the use of a mouse model in the 1940s and 1950s. When MOG protein from a different species was injected into mice, the immune system would attack the foreign MOG and also its own, leading to a demyelinating disease similar to MS.

When were MOG antibody tests first introduced for diagnosing MOG antibody disease in humans?

MOG antibody tests were first introduced in 2015 in the UK and in 2017 in the US.

Why was there initial confusion about the role of MOG antibodies in demyelinating diseases?

The initial confusion arose because when the MOG antibody was first discovered, it was thought to identify MS patients due to the demyelinating nature of the disease. However, only about 5% of people tested positive for it, and the test was not very specific, leading to many false positives.

What are the typical symptoms of MOG antibody disease?

Typical symptoms include optic neuritis, which can cause eye pain, blurry vision, and even vision loss. Some patients may also experience acute disseminated encephalomyelitis (ADEM), transverse myelitis, or brain lesions.

How does the demographic distribution of MOG antibody disease compare to other demyelinating diseases?

MOG antibody disease has a bimodal demographic distribution, affecting both children with ADEM and optic neuritis, and adults, with a slight predominance in Caucasians, although it is equally prevalent across all races.

What are the challenges in diagnosing MOG antibody disease?

Challenges include ruling out other conditions such as MS and aquaporin-4 for NMO, as some cases of MS might test positive for MOG. A definitive diagnosis requires the presence of inflammation in the central nervous system, a positive MOG antibody test, and the exclusion of other diseases.

What is the current approach to treating acute attacks of MOG antibody disease?

The current approach involves using high-dose steroids to quell the inflammation, followed by a slow weaning process to prevent rebound. In some cases, plasma exchange or intravenous immunoglobulin (IVIG) may be used if steroids are not effective.

What are some of the preventive treatments being explored for MOG antibody disease?

Preventive treatments being explored include high-dose IVIG, which has shown to reduce the failure rate compared to the regular dose. New approaches involve cytokine blockers like tocilizumab, which blocks IL-6, and other drugs like cosMOG and satralizumab that are being tested in clinical trials.