Review for 10.1186/s12876-018-0750-x (2018)

Reviewer ’s report  
 
Title: Is perceived intolerance to milk and wheat associated with the corresponding IgG and IgA  
food antibodies? A cross sectional study in subjects with morbid obesity and gastrointestinal  
symptoms  
 
Version: 0 Date: 15 Dec 2017  
 
Reviewer: Stephan C. Bischoff  
 
Reviewer's report:  
 
The paper addresses an interesting topic, that is the clinical relevance of IgG le vels in patients 
suffering from different types of adverse reactions to food. While most experts and societies 
expressed their doubts on it, some papers provided evidence for a rationale for IgG -guided 
elimination diets that improved symptoms in patients w ith IBS and other symptoms. However, 
the paper does not add very much to the field, mainly because several relevant questions remain 
unanswered.  
 
1. What is the rationale to include subjects with morbid obesity? If it is because of GI 
permeability changes, this needs to be shown. Did the patients have increased GI 
permeability? Did GI permeability correlate with the symptoms?  
 
 
2. How was „perceived food intolerance" objectified? If "gastrointestinal complaints" 
cannot be specified on an objective level, no di fferences in food -specific 
immunoglobuline levels can be expected. This questions the whole study project. What 
ist the rationale of the project finally?  
 
 
3. What is the justification of antigen selection?  
 
 
4. What is the justification of cut -offs of serum I gG and IgA levels?  
 
 
5. What is the justification of numbers of participants?  
 
 
6. Was lactose intolerance excluded? "Foods often perceived as triggers includes milk and 
dairy products" is only true if lactose intolerance is included. This is supposed to be not 
related to changes in specific immunoglobulin levels. Immune -mediated adve rse 
reactions to milk are rare in adults.  
 
 
7. What is the control group?  
Are the me thods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
No 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
No 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscr ipt: 
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursemen ts, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
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3. Do you hold or are you currently applying for any patents relating to the content of the  
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4. Have you received reimbursements, fees, funding, or salary from an org anization that 
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
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below.  If your reply is yes to any, please give details below.  
 
No competing interests!  
 
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