Review for 10.1186/s12876-020-01371-3 (2020)

Reviewer’s report
Title: Leukocytoclastic vasculitis as a rare dermatologic manifestation of Crohn's disease mimicking
cellulitis: a case report
Version: 0 Date: 03 Feb 2020
Reviewer: Mario Bento-Miranda
Reviewer's report:
Congratulations for your case report.
It is an interesting and illustrative case of one of the rarest extra-intestinal manifestations of Crohn's
disease, with an intriguing role of Ustekinumab.
However, I believe  the manuscript has  some  structural  and quotation inadequacies  that  could be
improved, enlightening this case report. In order to do so, please take into appreciation: 
TITLE
Would not use ":" twice in the title, seems unaesthetic. Also, it is a very rare disease, only with a few
reported  cases,  as  you  state  in  the  manuscript.  Would  substitute  "unusual"  for  "rare".  Example:
"Leukocytoclastic  vasculitis  as  a  rare  dermatologic  manifestation  of  Crohn's  disease  mimicking
cellulitis: a case report"
ABBREVIATIONS
Would abbreviate Leucocytoclastic vasculitis to "LC", not "LCV".
ABSTRACT 
  -comment on the presence or absence of simultaneous CD symptoms (abdominal pain/diarrhea?) 
  -line 33: substitute the misplaced comma for a full stop. 
  -line 33 - 24: "Patient's history was significant for psoriasis and treatment refractory CD requiring
monoclonal  antibody  therapy  with  ustekinumab."  this  interrupts  the  description  of  the  physical
examination. Would allocate it to the beginning of the case description
  -line 35: do you mean "reminder" or "remaining"?
  -line 36: would substitute "laboratory workup" for "complementary workup" (because of the CT scan
and other non-lab examinations)
  -line 43: do you mean "various" or "variable"?
  -line 43: exclude "it is"
  -line 44: do not abbreviate "EN" or "PG"
BACKGROUND
  -line 58: "being the largest human organ" - irrelevant/controversial. Would exclude. If to be kept, add
reference supporting it
  -line 66: would substitute the first "involved" by "affected" 
  -line 66: exclude "Leucocytoclastic vasculitis" and use the abbreviation
  -line 66: add the histologic term «karyorrhexis», for example "with fibrinoid necrosis and nuclear
debri (karyorrhexis) leading to post capillary venules damage". In the image legend you will be able to
use the histologic term alone making the description more elegant and precise.
  -line 71: consider using a more relevant and updated reference, such as the Chapel Hill Consensus
CASE PRESENTATION
  -line 79: apply Montreal classification
  -line 82: would describe ustekinumab dose, or add the term "standard", if so. Also, the regimen
intended (every 8 or 12 weeks? Other regimen?)
  -line 84 - 90: this is not organized as a timeline sequence of events, as CARE checklist recommends
on ITEM 7. The first admission to the UC should appear in first place, then the sequence described in
lines  76  -  78,  which  is  repeated  in  lines  88-90,  and  so  could  be  excluded  to  avoid  redundant
information. Would add note to presence or absence of CD symptoms (abdominal pain/diarrhea)
  -line 88: because you wrote "Urgency Care", you should write "Emergency Department"
  -line 92-93: "her psoriasis had been quiescent, and had required no recent treatment". It is written
before that infliximab and vedolizumab made the psoriasis worst. Make it clearer and/or merge the
sentences together in a logical manner. Also, exclude the comma after "quiescent," if the sentence is
maintained.
  -line 93-94: "A colonoscopy performed a month before, at the onset of her most recent CD flare" so if
the patient started ustekinumab 8 weeks before, and made this colonoscopy one month before, did she
have a flaire 4 weeks after starting ustekinumab? Or is it the same flare that motivated starting
ustekinumab and this is a scope to evaluate response? In line 129 you state that the flare was associated
with the vasculitis, but this relation and the ustekinumab timing should be clearer sooner in this section.
  -line 96: would change this to the end of line 116, to be in order with complementary workup
  -line  97-104:  to  be  in  line  with  CARE  checklist  -  ITEM  6  -  simplify  this  section  with  the
"SIGNIFICANT physical examination and IMPORTANT clinical findings". As an example "normal
vital signs" instead of describing each one.
  -line 105-116: this could also be simplified by excluding some normal findings description
  -line 114-115: Why did you do a LP if there were no neurological symptoms? would justify that
  -line 118-119: would reformulate "evaluation with skin biopsy of the rash" to "histologic evaluation of
skin with biopsy of the rash" 
  -line 122-123: no need to abbreviate Periodic Acid-Shiff if it is not used a second time
  -line 124: would start treatment in a new paragraph
  -line 125: what was the dose of budesonide? For how long? Was it tapered? Was she still on it after
those 6 months?
DISCUSSION
  -line 133: exclude the repeated term "associated"
  -line  136:  would  use  a  more  recent  reference,  such  as:  Disease-related  and  drug-induced  skin
manifestations in inflammatory bowel disease. Expert Rev Gastroenterol Hepatol. 2017 
  -line 138: "current postulates" Which ones? what are your references? There is no mention to
leucocytoclastic vasculitis in reference [6] that you provide in the end of the paragraph
  -line 144: would substitute "in the skin, or in the case of LCV," for "in the skin or, in the case of LCV,
within the small blood vessels of the dermis"
  -line 146-148: why does this comes up in here? How does this sentence relate with what is said before
about the pathogenesis of the vasculitis? Did you meant it to be the first sentence of the next paragraph
to contextualize the various presentation of the vasculitis?
  -line 150: would make note of the reference you are using as the first described case
  -line 151: do you mean "similar" or "similarly"?
  -line 151-153: would reformulate to avoid repeating the expression "cutaneous IBD manifestations" in
the same sentence
  -line 155: support your statements with appropriate reference/referring to your table
  -line 162 - 165: please use a reference supporting your statements on cellulitis 
  -line 165: do you mean "similar" or "similarly"?
  -line 165: would substitute the term "this case" with "ours" or "our patient" to avoid repetition of the
term "case"
  -line  180-182:  I  think  the  report  would  be  more  complete  with  a  more  developed
interpretation/comment  on  the  possible  role  of  ustekinumab.  If  not  the  cause,  could  it  be  a
trigger/enabler? Is the reintroduction enough to exclude it from picture? Could the superior dose of
budesonide be a confounder? 
IMAGES
Image 2: would edit and eliminate the "300µm" square from the upper right corner if possible, since it
is upside down
Image 3: would simplify legend to "Tender erythematous rash involving the extensor surface of the
lower limbs"
Image B: change it to "Image 4" instead of "B", to be in line with the other images and the tect
description (line 122); also, be consistent with Image 2 legend: "(H&amp;E, 10X)" in the end of the
sentence. As suggest before, substitute "leukocytoclastic debris" for "karyorrhexis" 
Are the methods 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.
Unable to assess
Are the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
Yes
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.
Not relevant to this manuscript
Quality of written English
Please indicate the quality of language in the manuscript:
Needs some language corrections before being published
Declaration of competing interests
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