In a study done by a group of Danish researchers on subjects who were admitted for ulcerative colitis there was no evidence for beneficial effects of appendictomy on admission rates in nationwide Danish hospitals in patients with UC. A cohort of patients who had an appendicectomy and their repeat admission for UC was studied. From 1981 to 1999, 202 subjects were identified as having an appendicectomy after their onset of UC. In this population based nationwide study with complete follow up, it was discovered that there was a moderate decline in hospital admission rates for UC after appendicectomy as compared to those who already had UC before their appendicectomy. The decline is not attributed to appendicectomy though because of the reference cohort showing a larger decline in admission rate.
Reference: Appendicectomy has no beneficial effect on admission rates in patients with ulcerative colitis; J Hallas, D Gaist, W Vach and H T Sørensen.
Furthermore, there is evidence released this week about the purpose of the appendix. An article published in the Journal of Theoretical Biology this week was referred to by the Associated Press. (http://news.yahoo.com/s/ap/20071006/ap_on_he_me/appendix_s_purpose) The article summarizes the work done by the researchers at Duke. It states that the purpose of the appendix (remember theoretically, unproven) is to act as a producer and store of good bacteria important in GI homeostasis. The article also goes on to describe the appendix as an outdated organ in the evolutionary timeline. The need for bacteria for the digestive system is not available to people from modern environments.
In conclusion, the study about the purpose of the appendix reinforces the study that an appendicectomy is not beneficial for patients with UC.
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The J. Theo. Biol. article itself was interesting, citing the appendix not as a vestigial remnant, as most people expect, but as an organ that evolved for a specific purpose, i.e. as a bacterial safe deposit box and biofilm generator for the colon. It's just that in the last 100 years our medical and hygene advances have removed the need in "industrialized" countries.
Unless, of course, you drink from one of those "pure mountain streams" in the Coors commericals...
I don't know about you, but the coors water from those commercials is fantastic
OK, guys, let's keep this thread professional.
So about the article: I see it's the Journal of Theoretical Biology, so I assume there are no data?
If this hypothesis were true,then would you predict that people who had appendectomies would have various digestive problems thereafter, due to the inability to generate a good biofilm? There are thousands of such people, has anyone reported that?
here is a link to the paper (open in pdf), there is a data table on page 19: http://www.sciencedirect.com/science?_ob=ArticleListURL&_method=list&_ArticleListID=629229616&_sort=d&view=c&_acct=C000059541&_version=1&_urlVersion=0&_userid=56761&md5=333da568720bdba72a4130f4f9383f14
According to a study called: "Appendicectomy has no beneficial effect on admission rates in patients with ulcerative colitis" J Hallas, D Gaist, W Vach, H T Sorensen, they do not report on instabilities to generate good biofilm but do give insight into the subject. They find that an appendicectomy has no beneficial effect of patients with UC. Some follow up studies would be helpful, I have not come across any so far.
since earlier it was mentioned that the medical and hygiene advances have removed the need for the appendix in industrialized countries, i actually found that to not be enitrely true. The hygiene hypothesis suggests that improvements in medical and sanitation may give rise to an overactive immune system since it is understimulated and thus may contribute to an increased rate of appendicitis.
R. Randal Bollinger, Andrew S. Barbas, Errol L. Bush, Shu S. Lin and
William Parker, Biofilms in the large bowel suggest an apparent function of the human vermiform
appendix, Journal of Theoretical Biology (2007),
Interesting, the idea that industrialized countries harbor "overactive" immune systems and that there was no need for a "safe house of commensal bacteria" Wasn't the media, not long ago, worried that our nation's over-sanitization craze might be detrimental to optimal immune function?? Oh heavens, if I undergo an appendectomy where shall I keep my extra Bifidus Regularis I pay such a pretty penny for at King Soopers?!
If you are having problems with the link go to http://www.sciencedirect.com/
and search the name of the paper: Biofilms in the large bowel suggest an apparent function of the human vermiform appendix
This is an interesting theory on the appendix. This reaffirms if you have an appendicectomy UC is emminent based off genetic factors.
I found this website that states appendectomy protects against the development of ulcerative colitis and reduces its recurrence: results of a multicenter case-controlled study in Japan.
http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&uid=11316158&cmd=showdetailview&indexed=google
I found it interesting that the study was done in japan, where ulcerative colitis is very uncommon and homogenous. 325 patients with UC were matched with 325 controlled patients matched in age, sex, smoking status, and previous medical treatment. The results were the uc group had a significantly lower percentage of appendectomies performed compared to the control group.
While it has been well re-capped that appendicectomy has no beneficial effect on the admission rate of patients with ulcerative colitis, what about Crohn's Disease? Why choose UC? And why focus on 'admission rates'? It seems to me that the presence of a bacterial ‘safe house’ to support the immune system in the incidence of infection would be useful in fending off IBD, which is speculated to arise from a(n) (bacterial) infection not properly controlled by a well-functioning immune system. The article by Bollinger, etc. notes that the appendix is expected to facilitate the exclusion of pathogens, so why take it out? Thus, I think a study that focuses more on appendicectomy that is closely followed by the manifestation of IBD would provide us with more useful information about the role of the appendix in IBD.
I believe the study tends to focus on UC because of its presence downstream from the appendix, where as CD affects the entire gut. Admission rates are a good marker for the study because it is a method used to track cases. The researchers cannot go door to door searching for IBD.
As for why people would have their appendix removed, untreated, a patient suffering from appendicitis has high mortality mainly caused by peritonitis and shock.
Hobler, K., Acute and Suppurative Appendicitis: Disease Duration and its Implications for Quality Improvement, Permanente Medical Journel, volume 2, #2, Spring 1998.
It would also be interesting to follow a group of people who were treated for Giardia infestation. The treatment regimen, which consists of massive doses of one of several antibiotics, should systematically kill off just about any non-resistant bacterium; including the "helpful" ones in the appendix. In fact, since the advent of systemic antibiotic treatments, how useful could the appendix be? I.e., every time that you are put on antibiotics for 7-12 days, you are effectively wiping out all gut and appendix colonies as well? Does the appendix really store bacterial biofilm as well as it did before antibiotics?
And if increased hygiene is causing the immune system to overrespond to bacteria in the appendix (in some people), doesn't that make removing the appendix prophylactically an even better idea?
JessicaR495...I'm willing to bet the reason they had to focus on "admission rates" as the dependent variable is because it was a retrospective or outcomes study. Often in large, macro-level studies you have to tailor the questions you ask according to the data collection mechanisms you have in place. So, it is different from a priori hypothesizing, where you then design your data collection. In hospital systems, those researchers are often at the mercy of the databases in place...and the data are only as good as those collection mechanisms. Only a few thoughts...you asked a very good question. TLH
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