In the current issue of the German Medical Journal, there is a nice summary of drug therapy in the simultaneous occurrence of Multiple Sclerosis (MS) and other chronic inflammatory diseases such as psoriasis, rheumatoid arthritis and chronic inflammatory bowel diseases (ulcerative colitis and Crohn’s disease) (Bittner et al. Dtsch Arztebl Int 2025; 122: 427–32).
The co-occurrence of autoimmune diseases is not uncommon – MS-Docblog had already reported on the occurrence of several autoimmune diseases: MS and other autoimmune diseases. The authors of the aforementioned summary assume that about 5% of MS sufferers in Germany suffer from another autoimmune disease. I can certainly understand this in my own everyday practice. The question of how to proceed in the case of simultaneous occurrence of MS and other autoimmune diseases is not rare and requires good coordination with other specialist disciplines.
An important principle in the treatment of these patients is to choose therapies that, in the best case, not only have an effect on MS but also treat the accompanying autoimmune disease.
For example, fumarates (dimethyl fumarate/diroximel fumarate) are suitable for the treatment of psoriasis as well as the treatment of MS. Ozanimod (Zeposia®) is not only approved for the treatment of active relapsing MS but also for the treatment of ulcerative colitis and is in clinical testing for Crohn’s disease. And finally, the highly effective MS therapies with anti-CD20 antibodies (ocrelizumab, ofatumumab, ublituximab) are also an effective concept for the treatment of rheumatoid arthritis, where rituximab has had a high status as a therapeutic agent for many years.
MS and other autoimmune diseases such as…
However, it is possible that the potency of the MS drugs is not sufficient to sufficiently treat a co-occurring autoimmune disease. In such cases, one can resort to preparations that do not have approval for both diseases, but on the basis of theoretical considerations and clinical case series, also have an effect on other autoimmune diseases. An example of this is secukinumab, an antibody against IL17, which is approved for the treatment of psoriasis, is more potent than the fumarates and for which data exist suggesting an effect on MS. Another example would be natalizumab, a very potent drug for the treatment of MS, which was also previously investigated for ulcerative colitis but never received approval.
On the other hand, it is also possible that when autoimmune diseases occur simultaneously, effective concepts from several indication areas are combined with each other. This initially moves into unknown territory – especially since combination therapies in neurology have no tradition.
In rheumatology, however, such combination therapies of highly effective substances are quite normal and established. Therefore, the interdisciplinary cooperation already mentioned by me in such cases is of great importance and contributes to better treatment of those affected.
… psoriasis, rheumatoid arthritis, Crohn’s disease, ulcerative colitis
Finally, in addition to effectiveness, the aspect of unwanted side effects must be mentioned. For the treatment of many autoimmune diseases in internal medicine and dermatology, so-called TNF-alpha blockers play an important role. TNF-alpha is an inflammation-promoting messenger substance that also plays an important role in MS. However, we had to recognize in the past that the use of TNF-alpha blockers leads to a worsening of MS. Furthermore, it has been observed that a few patients who were treated with anti-TNF-alpha antibodies for rheumatoid arthritis or psoriasis developed MS. It is unclear whether a subclinical disease was unmasked or whether the anti-TNF-alpha drug co-caused the MS. Overall, we in neurology draw the lesson from this that TNF-alpha blockers must be avoided in MS patients with other autoimmune diseases.
In summary, it can be stated that the simultaneous occurrence of MS and other autoimmune diseases is a highly interesting field and treatment requires interdisciplinary cooperation and personalized strategies in order to optimally weigh up effectiveness and side effects.
This post was translated from German to English with the help of AI.
