LE&RN symposium series: Primary lymphedema: how science has changed patient care
(by prof. dr. Mortimer)
Research takes a lot of time and patience. Sometimes it may seem as if these tiny results don’t make a difference. When having such negative thoughts the presentation of prof. dr. Mortimer on the symposium series of Lymphatic Education & Research Network might cheer you up. In this presentation prof. dr. Mortimer explains where science has brought us regarding primary lymphoedema.
He started his presentation by telling that the lymphatic system is apparently not such a popular specialty in Medicine (We hear ya, we don’t understand it either, because it’s so interesting!). However, he continued the presentation by saying that the lymphatic system is a very important system in our body. If it wasn’t for research, we would still think that the blood vessels are the most important for fluid exchange. Thanks to research we now know that isn’t true and that instead the lymphatic system is predominantly responsible for draining tissue fluid.1 So, if there is some swelling, we now know the lymphatic system is an important system to look at.
This might already make you feel a bit more positive about scientific research, but wait, there is more: A new classification system for primary lymphoedema! Bit of an anticlimax, you say? Let’s prove you wrong. Prof. dr. Mortimer gives several reasons why this is an important development:
In the presentation he points out that in primary lymphoedema the structure and the function of the lymphatic system is impaired as a consequence of a developmental or genetic problem. Until 20 years ago there were only three subgroups in primary lymphedema: congenita, praecox and tarda. To which group a person belonged just depended on the age of development of this primary lymphoedema (congenital, pubertal or late onset in life). This doesn’t sound so bad, but it doesn’t give much information. Especially when in primary lymphoedema different physical characteristics can be seen, for example, age of onset, the location of the edema, associated features,… It was time for a new classification system.
That’s where research stepped in again. Prof. dr. Mortimer talks about researchers starting to group primary lymphoedema according to their similar features2 (for example, the location, the age of onset,…). The same genetic cause could be suspected in patients with similar features. By grouping patients with primary lymphoedema with similar features, they found a couple of mutations and genetic faults which cause primary lymphoedema. If this doesn’t blow your mind yet, then maybe the following different advantages prof. dr. Mortimer talks about might:
- By knowing the genetic fault a more specific diagnosis than just “primary lymphoedema” can be given.
- If a specific gene is found, more information can be given about the natural history of that type of lymphoedema
- If the responsible gene is detected it could also explain other possible present abnormalities, depending on what the function of that specific gene is.
- It also gives information about the likelihood of passing it on to the next generation.
- It could also explain the mechanism of the disease and therefore providing a target for future therapies. Until now conservative therapy is still the first choice of treatment, but maybe in the future other therapies can be developed based on the information we receive from this classification system.
This presentation gave us new hope and we are excited and motivated to do further research. We hope you are too!
We definitely recommend you to listen to the whole presentation of prof. dr. Mortimer yourself. In his presentation he also clarifies the classification pathway3 they developed with some good examples. He also took the time to answer a lot of questions!
The presentation can be found on following website: https://lymphaticnetwork.org/symposium-series. Here you can also listen to a lot of other interesting presentations regarding Lymphoedema. Enjoy!
- Levick JR, Michel CC. Microvascular fluid exchange and the revised Starling principle. Cardiovasc Res. 2010 Jul 15;87(2):198-210. doi: 10.1093/cvr/cvq062. Epub 2010 Mar 3. PMID: 20200043.
- Connell FC, Gordon K, Brice G, Keeley V, Jeffery S, Mortimer PS, Mansour S, Ostergaard P. The classification and diagnostic algorithm for primary lymphatic dysplasia: an update from 2010 to include molecular findings. Clin Genet. 2013 Oct;84(4):303-14. doi: 10.1111/cge.12173. Epub 2013 Jun 27. PMID: 23621851.
- Gordon K, Varney R, Keeley V, Riches K, Jeffery S, Van Zanten M, Mortimer P, Ostergaard P, Mansour S. Update and audit of the St George's classification algorithm of primary lymphatic anomalies: a clinical and molecular approach to diagnosis. J Med Genet. 2020 Oct;57(10):653-659. doi: 10.1136/jmedgenet-2019-106084. Epub 2020 May 14. PMID: 32409509; PMCID: PMC7525776.