In the diagnostic process of Celiac disease, there are two parts – bloodwork and endoscopy with intestinal biopsy. In the diagnostic process, someone must be consuming gluten in order for either of the tests to be accurate. Together they paint a picture of whether the patient has celiac disease or not. Specifically, I want to talk about Marsh Scores.
Marsh Scores describe the health of the small intestine. It describes the height of the villi, spaces between the villi, and the number of lymphocytes in the top layer of small intestine cells. At least two biopsies should be taken from the 2nd and 3rd portion of the duodunem or first part of the small intestine immediately after the stomach.
Villi are small finger like projections within the lining of the small intestine that absorb food. There are spaces between the villi called crypts. There should be a 3:1 or 5:1 ratio between the villi and the crypts.
In the lining of the intestine, there are lymphocytes that exist in the top layer of the small intestine or epithelium. In normal patients, there should be fewer than 30 lymphocytes per 100 epithelial cells. Normally on the pathology report you will see the words “epithelial lymphocytes” to refer to these cells.
A Marsh score is a classification of villi height, space between the villi or crypts, and number of epithelial lymphocytes. There are four categories – Marsh 0, Marsh 1, Marsh 2, Marsh 3a, Marsh 3b, and Marsh 3c or Marsh 4. I’ll explain that one further down.
Marsh 0 – Normal healthy villous architecture and normal epithelial lymphocytes. Congratulations, all is well.
Marsh 1 – Normal villous architecture, however the number of epithelial lymphocytes is increased. This designation is controversial in the diagnosis of Celiac disease. I’ve seen studies that say Marsh 1 is indicative of early celiac disease or latent celiac and I’ve seen other studies that say Marsh 1 can be caused by a number of factors including h. pylori, SIBO, and NSAID use. Marsh 1 makes a definitive diagnosis murky. If you have this designation, please talk to your doctor and figure out a plan for moving forward. It probably involves repeat testing and repeat endoscopy.
Marsh 1 may also be seen on those with celiac disease following a gluten free diet – it would indicate healing.
Marsh 2 – This designation unusual. It has three characteristics, two the same as Marsh 1 and one change. First characteristic is normal villous architecture. The villi are good and healthy. Yay! Two, increased epithelial lymphocytes – more than 30 lymphocytes per 100 epithelial cells. Third and this is the new one, increased crypt hyperplasia – the space between the villi is bigger than normal. Marsh 2 is an unusual designation typically seen in those with Dermatitis Herptiformis (DH)- the Celiac skin rash. If you have DH, the fastest and easiest way to diagnosis is a skin biopsy. If you have DH, yay, you get a gluten free diet for life!!
Marsh 3a and Marsh 3b – This is where the diagnosis of celiac disease is absolute. There are increased lymphocytes and increased crypt hyperplasia – too many lymphocytes and the space between the villi are too big. Now, we are into villous blunting. The villi to crypt ratio is below 3:1 or 5:1. The villi look cut off. Marsh 3a means that there is mild atrophy and Marsh 3b means there is marked atrophy.
Marsh 3c or Marsh 4 – This is not where you want to be. This means increased lymphocytes, increased crypt hyperplasia, and complete villous atrophy. It means the villi are completely eroded. Here again, the diagnosis of celiac is absolute.
Interestingly, there is no correlation between the celiac blood panel and the Marsh score. It is possible to be just barely positive on the blood work and have Marsh 3c/4 level damage. It is also positive to have sky high blood work and only have Marsh 1 level damage. That makes life really interesting, which is why you need both in order to accurately asses celiac disease.
As a side note, ImmugenX is working on a way to asses intestinal damage without the need to undergo the endoscopy. In essence, they have a statin drug that is only absorbed in the small intestine. They take blood work to asses how much of the statin is absorbed to determine the level of villous atrophy. The less absorbed means the more damaged the villi.
There is also a capsule endoscopy or pill cam. A pill is swallowed and it takes pictures all along the small and large intestine. The pill cam can reach places that the endoscopy cannot. The downside is that the pill cam cannot take biopsies. So, if you have visible damage, the pill cam might pick it up.
I hope that helps with the understanding of Marsh scores. All the pathology reports should have this designation and if not, you can confirm the designation with your doctor. Mine don’t actually say Marsh scores, but in talking with my doctor he confirmed my scores.
I was Marsh 3a, one year after diagnosis in December 2013. Marsh 3b in March 2016. That isn’t going the right way is it? I just got a new EGD while in the study. I wonder if I’ll ever get that information.
Link to source from image above.