Showing posts with label autoimmune. Show all posts
Showing posts with label autoimmune. Show all posts

There are patients with "gluten sensitivity" in whom neither allergic nor autoimmune mechanisms can be identified

There are 3 main forms of gluten reactions:

- allergic (wheat allergy)
- autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia)
- possibly immune-mediated (gluten sensitivity) ("non-celiac gluten sensitivity" or NCGS). We need to be extremely cautious in calling somebody gluten sensitive. It may be sensitivity to FODMAPs instead. It could have nothing to do with gluten at all. http://buff.ly/1k2UjNW

Celiac disease is the most common genetically based food intolerance (1% prevalence among general population) (JAMA 2014, http://buff.ly/1cJWgFy).

From BMJ:

It is now becoming clear that, besides those with celiac disease or wheat allergy, there are patients with gluten sensitivity in whom neither allergic nor autoimmune mechanisms can be identified. It has been estimated that, for every person with celiac disease, there should be at least six or seven people with non-celiac gluten sensitivity. Gluten sensitivity may therefore affect 6-10% of the general population.

Patients with gluten sensitivity have negative immuno-allergy tests to wheat and negative celiac disease serology; normal endoscopy and biopsy; clinical symptoms that can overlap with those of celiac disease, irritable bowel syndrome, and wheat allergy; and they show a resolution of symptoms when started on a gluten-free diet.

Currently there are no laboratory biomarkers specific for gluten sensitivity, and the diagnosis is based on exclusion criteria; elimination of gluten-containing foods from the diet followed by an open challenge is most often used to establish whether health improves with the elimination or reduction of gluten from the patient’s diet.

New nomenclature and classifications are proposed (see the figures below).



"Fibromyalgia of the gut"

Some physician have labeled "gluten sensitivity" "fibromyalgia of the gut" to reflect the presence of symptoms in the absence of pathological findings. The BMJ editor-in-chief reflected on these doubts in an editorial: Gluten sensitivity: real or not?.

Since there are no biomarkers, gluten sensitivity is the ultimate diagnosis of exclusion. The worldwide shift to the Mediterranean diet may explain the rising prevalence of gluten sensitivity. The has been an “explosion of requests” for serological testing for celiac disease since 2007.

3 million Americans are living with celiac disease

Celiac disease, an immune system reaction to gluten in the diet, is four times as common today as it was 50 years ago. Lack of awareness of celiac could be contributing to a delay of up to 11 years in diagnosis of adults in North America (http://goo.gl/sy778).

This is an informative and beautifully designed video by the University of Chicago Celiac Disease Center. It looks like an infographic made into video - have a look:



New classification is being proposed for gluten-related disorders: celiac disease; dermatitis herpetiformis; gluten ataxia; wheat allergy; gluten sensitivity. WSJ, 2012.

Recent studies support the existence of the new condition nonceliac gluten sensitivity which is defined as symptoms with negative celiac antibodies and biopsy (http://goo.gl/57IlB).

References:

Non-coeliac gluten sensitivity | BMJ, 2012.

Gluten sensitivity: real or not? | BMJ http://buff.ly/ZgKgK1

Does gluten sensitivity in the absence of coeliac disease exist? | BMJ http://buff.ly/RvC7zg

New nomenclature and classification of gluten-related disorders - http://www.biomedcentral.com/1741-7015/10/13/figure/F1

Algorithm for the differential diagnosis of gluten-related disorders, including celiac disease, gluten sensitivity and wheat allergy - http://www.biomedcentral.com/1741-7015/10/13/figure/F4

Spectrum of gluten-related disorders: consensus on new nomenclature and classification. Anna Sapone et al. BMC Medicine 2012, 10:13 doi:10.1186/1741-7015-10-13.

Image source: Colon (anatomy), Wikipedia, public domain.

Disclaimer: I am an Assistant Professor of Medicine and Pediatrics at University of Chicago.

Comments from Google Plus:

Neil Mehta: thanks for sharing this. Besides the content itself, Really like this type of articles where a patient can write about medical lessons learned. 


Howard Luks: That's me :-) thanks for sharing this! My GI guy will see it in the AM 
Autoimmune hepatitis - 2013 Lancet review

Autoimmune hepatitis - 2013 Lancet review

In common with many autoimmune diseases, autoimmune hepatitis is associated with non-organ-specific antibodies in the context of hepatic autoimmunity.

Autoimmune hepatitis can present in acute or chronic forms.

Remission is achievable in up to 85% of cases. For the remaining patients, immunosuppression is an option.

Liver transplantation provides an excellent outcome for patients with acute liver failure or complications of end-stage liver disease, including hepatocellular carcinoma.

References:

Autoimmune hepatitis: The Lancet http://bit.ly/1aApnxp

Neurological and autoimmune disorders after influenza vaccination: no change in risk for Guillain-Barré syndrome, MS, type 1 diabetes, or RA

This Swedish retrospective cohort study, published in BMJ, examined the risk of neurological and autoimmune disorders in people vaccinated against pandemic influenza A (H1N1) with Pandemrix (GlaxoSmithKline) compared with unvaccinated people over 8-10 months.


Image of the H1N1 Influenza Virus, CDC.

One million people were vaccinated against H1N1 and 900,000 remained unvaccinated.

Excess risks among vaccinated people were of low magnitude, but present, for:

- Bell’s palsy (hazard ratio 1.25)
- paresthesia (1.11)
- inflammatory bowel disease (IBD)

Risks for Guillain-Barré syndrome, multiple sclerosis, type 1 diabetes, and rheumatoid arthritis remained unchanged.

The risks of paresthesia and inflammatory bowel disease (IBD) among those vaccinated in the early phase (within 45 days) of the vaccination campaign were significantly increased; the risk being increased within the first 6 weeks after vaccination.

The risks were small but significant among more than one million vaccinated, but only in high risk groups targeted for early vaccination and who were likely to have earlier comorbidity.

The absolute risk of Bell’s palsy was low, 6.4 cases per 100 000 vaccinated population.

References:

Neurological and autoimmune disorders after vaccination against pandemic influenza A (H1N1) with a monovalent adjuvanted vaccine: population based cohort study in Stockholm, Sweden. BMJ 2011; 343:d5956 doi: 10.1136/bmj.d5956 (Published 12 October 2011).