Review for 10.1186/1471-230X-11-103 (2011)

Reviewer's report
Title:Two cases of monomicrobial intrabdominal abscesses due to KPC- 3
Klebsiella pneumoniae ST258 clone
Version: 2Date:30 June 2011
Reviewer: Wen-Liang Yu
Reviewer's report:
Two cases of monomicrobial intrabdominal abscesses due to KPC- 3 Klebsiella
pneumoniae ST258 clone
Abstract:
1. “Background: Knowledge of the etiology of pyogenic liver and pancreatic
abscesses is an important factor in the success of combined surgical and
antibiotic treatment. Polymicrobial etiologies are most commonly reported in
Europe.”
Comment:
-What is the clinical significance of monomicrobial etiology in these abscesses?
Introduction:
1. “Pyogenic abdominal abscess by carbapenemase-producing Gram-negative
pathogens is a severe, post-surgical infectious complication [1,2].”
Comment:
-One sentence could not be a paragraph.
-It seems that the references [1, 2] do not mainly focus on the
carbapenemase-producing Gram-negative pathogens that cause a severe,
post-surgical infectious complication. The authors may cite more appropriate
papers relevant to the topic of this manuscript.
2. “Since 1986, the presence of these microorganisms in liver or pancreatic
abscesses has been frequently associated with worse outcomes, regardless of
which therapeutic strategy is adopted [3].”
Comment:
-The authors may introduce the pathogenesis of post-operative liver abscess or
pancreatic abscesses and their common causative organisms.
-It seems that the reference [3] does not mainly focus on the outcome of the
carbapenemase-producing microoraganisms that cause liver or pancreatic
abscesses. The authors may cite more appropriate papers relevant to the above
sentence.
3. “Moreover, reports showed a higher incidence of septic metastatic lesions in
patients with Klebsiella pneumoniae liver abscess and fatality case are also
described [4,5].”
Comment:
-This description is not relevant to the topic of this manuscript. Besides, following
the previous two sentence in the section, it is not clear why the authors mention
the Klebsiella pneumoniae liver abscess here.
-The authors may introduce the characteristics and classification of different kind
of carbapenemases.
4. “In this report, we describe two HIV- negative patients intrabdominal
abscesses caused by extremely drug-resistant Klebsiella pneumoniae
carbapenemase (KPC) 3 – producing K. pneumoniae (Kp) Sequence Type (ST)
258.”
Comment:
-Before this sentence, the authors may introduce the characteristics and
classification as well as the clinical significance of KPC and some epidemiology
information of ST, including ST 258 or other common ST numbers.
-It is not clear why the authors want to describe the KPC-KP abscesses in this
report. What are the main goals of the paper? Did the authors want to highlight
the importance of KPC-3 in the hospital? Did the authors discover new or
effective therapeutic strategy for treating the KPC-3 KP abscesses?
Case 1
1. “Combined intravenous colistin (5 mg/kg/day) and tigecycline (recommended
dosage regimen 100 mg initially, followed by 50 mg every 12 hours) was started.”
Comment:
-Should the “ colistin” be colistin sulfomethate sodium? Or the authors may use
international units (IU) for the dosage of coltistin.
Discussion:
1. “Although K. pneumoniae has previously been identified in western Europe as
a causative agent of liver abscesses, the infection has rarely been
monomicrobial, as it appeared in both of our cases [1].”
Comment:
-The authors may discuss the difference of clinical significance between the
monomicrobial and polymicrobial liver abscesses, and their relevance to
antimicrobial resistance.
- The authors may try to explain the occurrence or portal of entry of the KPC-KP
in the cases in this report.
2. “ In our experience, eradication of an MRD pathogen, such as KPC-Kp, was
obtained by combination therapy. As recently reported, antibiotic combination
therapy might be more efficient than single antibiotics in combating gram
negative MDR organisms [18].”
Comment:
-The authors may provide experience from papers that also used combination
therapy with colistin and tigecycline to treat the intra-abdominal abscess.
3. “Moreover, when monotherapy is given for a long time, as is the case in the
treatment of abscesses, resistance to it can develop [19-20].”
Comment:
-The authors may provide experience from papers that resistance of KPC-KP to
colistin or tigecycline did happen while using alone to treat abscess diseases.
Level of interest: An article of importance in its field
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.