Review for 10.1186/1471-230X-5-31 (2005)

Reviewer's report 
 Complement Activation Capacity in Plasma before and during High-dose Prednisolone Title: 
Treatment and Tapering in Exacerbations of Crohn's Disease and Ulcerative Colitis 
 2  14 April 2005 Version: Date: 
 Sk. Md. Fazle M Akbar Reviewer: 
Reviewer's report: 
General 
It is generally accepted that an imbalance in immune responses prevails in patients with inflammatory bowel diseases, however, the nature of the defects have neither been clarified nor wellunderstood. It is elusive whether the defects lead to the initiation of the diseases or these are 
consequences of the pathological processes. To have better insights about this, several 
investigators have analyzed about cytokine production, complement activation and lymphocyte 
functions in these pathological conditions. 
In the present manuscript, Erik-Zimmermann et al. have reported about complement activation in 
plasma during prednisolone therapy in patients with inflammatory bowel diseases. This is not the first communication regarding complement activation in patients with inflammatory bowel from their 
group. They have also dissected the complement pathway in these patients previously (References 
19, 21 and 25). The data provide in this study do not support what they reported in their previous 
communication. Naturally, there are major concerns about the sensitivity and specificity regarding 
the methods of estimation of complement activation in plasma in these patients. 
Taken together, the originality of the study is not limited. There are some queries about 
methodology. There is no inclusion and exclusion criteria of patients in this study, which severely 
compromised the impact of the study. The conclusion is not balanced. 
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Major Compulsory Revisions (that the author must respond to before a decision on publication can 
be reached) 
Specific comments: 
A] The same group has published their study regarding complement activation in plasma in patients 
with Crohn disease [CD]. They have reported that C3-activation capacities [C3-CA] were not 
different between patients with CD and normal controls [Zimmermann-Nielson E et al. Scand J 
Gastroenterol 2003; 38: 1050]. In this manuscript, they have shown that the levels of C3-CA were 
significantly higher in patients with CD compared to normal controls. The authors assumed that this discrepancy is attributable to the difference in clinical conditions of the patients. But, this is not acceptable until it is supported by experimental evidences. This is an important issue because it 
casts shadow over reproducibility and sensitivity of their estimation method. There is no data if the 
methods were sound or not. In order to validate their observation, there is a need to include a group of patients with CD complicating by fistulizing ano-rectal disease (similar to their previous manuscript) and the levels of C3-CA in the plasma of those patients should be shown. If patients 
with CD complicating by fistulizing ano-rectal disease show low levels of CD-CA, there is a need 
provide logical discussion regarding this. 
B] This study was designed to evaluate complement activation during prednisolone therapy in 
patients with CD and ulcerative colitis [UC]. There are several points regarding the subjects in this 
manuscript those have not been described but should be clarified. At inclusion, 6 UC and 1 CD 
patients were getting steroid by rectal enema, respectively. Did these patients continued to get 
steroid after systemic administration of steroid? What were the levels of markers of complement 
activation of these patients before the start of high dose of prednisolone? How, these patients were given prednisolone? The patients were given 1 mg/kg of prednisolone. Was it started instantly? The inclusion and the exclusion criteria should be mentioned. If there are no such criteria, the authors 
should mention the nature of the study. How the patients were included. Is it a pilot study? 
C] The authors have shown the data of complement activation as Median and range. The authors 
have written the levels of C3-CA decreased significantly after the start of prednisolone therapy. The 
data in Table 1 shows that ranges of levels of C3-AC were almost similar before and at different 
points after start of prednisolone therapy. In this situation, the Median values provide insignificant 
information. The author should show the levels of C3-CA individual patients, at least those of some 
representative cases. 
[D] The levels of MBL concentration shows marked variation among patients with CD and UC. Does 
it relate to any clinical parameters? This is also seen in normal controls. The levels of MBL vary 
more than 1700 times among normal individuals. What is the importance of such fluctuating 
parameter? 
E] Do the levels of CD-CA in plasma show any correlation with the levels of damage of colonic 
mucosa in patients with CD and UC? If there is no correlation, it will be premature to comment on 
their prognostic value. [This has been proposed by the authors in Conclusion and Discussion]. 
F] The statistical analysis should be checked by a statistician. In Table 1, they have the data of 4 
groups. Is the statistical method is sound? 
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Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the 
author can be trusted to correct) 
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Discretionary Revisions (which the author can choose to ignore) Table 2 can be given first as Table 1. 
 Unable to decide on acceptance or rejection until the authors have responded to the What next?: 
major compulsory revisions 
 An article of limited interest Level of interest: 
 Acceptable Quality of written English: 
 Yes Statistical review: 
Declaration of competing interests: 
'I declare that I have no competing interests'.