Differences in characteristics between healthcare-associated and community-acquired infection in community-onset Klebsiella pneumoniae bloodstream infection in Korea
BMC Infectious Diseases
Differences in characteristics between healthcare-associated and community-acquired infection in community-onset Klebsiella pneumoniae bloodstream infection in Korea
Younghee Jung 0
Myung Jin Lee 2
Hye-Yun Sin 0
Nak-Hyun Kim 2
Jeong-Hwan Hwang 2
Jinyong Park 2
Pyoeng Gyun Choe 1 2
Wan Beom Park 1 2
Eu Suk Kim 0 1
Sang-Won Park 1
Kyoung Un Park 1 3
Hong Bin Kim 0 1
Nam-Joong Kim 1 2
Eui-Chong Kim 1 4
Kyoung-Ho Song 0 1
Myoung-don Oh 1 2
0 Department of Internal Medicine, Seoul National University Bundang Hospital , 173 Gumi-ro, Bundang-gu, Seongnam 463-707 , Republic of Korea
1 Seoul National University College of Medicine , Seoul , Korea
2 Department of Internal Medicine, Seoul National University Hospital , Seoul , Korea
3 Department of Laboratory Medicine, Seoul National University Bundang Hospital , Seongnam , Korea
4 Department of Laboratory Medicine, Seoul National University Hospital , Seoul , Korea
Background: Healthcare-associated (HCA) infection has emerged as a new epidemiological category. The aim of this study was to evaluate the impact of HCA infection on mortality in community-onset Klebsiella pneumoniae bloodstream infection (KpBSI). Methods: We conducted a retrospective study in two tertiary-care hospitals over a 6-year period. All adult patients with KpBSI within 48 hours of admission were enrolled. We compared the clinical characteristics of HCA and community-acquired (CA) infection, and analyzed risk factors for mortality in patients with community-onset KpBSI. Results: Of 553 patients with community-onset KpBSI, 313 (57%) were classified as HCA- KpBSI and 240 (43%) as CA-KpBSI. In patients with HCA-KpBSI, the severity of the underlying diseases was higher than in patients with CA-KpBSI. Overall the most common site of infection was the pancreatobiliary tract. Liver abscess was more common in CA-KpBSI, whereas peritonitis and primary bacteremia were more common in HCA-KpBSI. Isolates not susceptible to extended-spectrum cephalosporin were more common in HCA- KpBSI than in CA-KpBSI (9% [29/313] vs. 3% [8/240]; p = 0.006). Overall 30-day mortality rate was significantly higher in HCA-KpBSI than in CA-KpBSI (22% [70/313] vs. 11% [27/240]; p = 0.001). In multivariate analysis, high Charlson's weighted index of co-morbidity, high Pitt bacteremia score, neutropenia, polymicrobial infection and inappropriate empirical antimicrobial therapy were significant risk factors for 30-day mortality. Conclusions: HCA-KpBSI in community-onset KpBSI has distinctive characteristics and has a poorer prognosis than CA-KpBSI, but HCA infection was not an independent risk factor for 30-day mortality.
Klebsiella pneumoniae; Bacteremia; Community-acquired infections; Healthcare-associated; Community-onset infection; Epidemiology
Within the last decade, the concept of
healthcareassociated (HCA) infection has been introduced, and
HCA infection has been described as an epidemiological
category different from both community-acquired (CA)
and nosocomial infection [1,2]. Most importantly,
mortality in HCA infection seems to be generally higher
than that in CA infection, and similar to that in
nosocomial infection [2-4]. However, there are conflicting
results regarding whether HCA infection is an
independent risk factor for mortality in bloodstream infection
[1,5]. A few pathogens have been studied in terms of
HCA infection with S. aureus dominating the research,
and these studies reported inconsistent data concerning
the impact of HCA infection on mortality [6-13]. For
gram-negative bacteria, the data on the impact of HCA
infection on mortality were conflicting, as well [9-12].
Klebsiella pneumoniae is one of the most important
gram-negative bacteria clinically, and K. pneumoniae
bloodstream infection (KpBSI) has a mortality rate of
about 20% [11,14-16]. Classically, KpBSI was simply
classified into CA and nosocomial infections depending
on bacteremia onset time: within 48 hours and after 48
hours of admission, respectively, and the different
characteristics of CA-KpBSI versus nosocomial KpBSI have
been well evaluated [11,14,15,17,18]. CA-KpBSI is
usually associated with liver abscesses in patients with
diabetes in East Asian countries, such as Korea and Taiwan
[19-22]. On the other hand, nosocomial KpBSI presents
as primary bacteremia and/or pneumonia in patients
with severe underlying diseases like malignancies. Thus,
nosocomial infection has a higher mortality than CA
infection [11,14,15,17,18]. However, there have been few
studies of HCA-KpBSI [11-13]. Therefore, we aimed to
evaluate the impact of HCA infection on mortality and
to compare the clinical characteristics of HCA and CA
infection in patients with community-onset KpBSI.
Study setting and patients
We conducted a retrospective study of the medical
records of the patients with KpBSI from January 2003 to
December 2008 at Seoul National University Hospital (a
1,600-bed tertiary-care hospital, Seoul, Korea) and Seoul
National University Bundang Hospital (a 900-bed
tertiary-care hospital, Seongnam, Korea). All adult patients
(18 year) who had KpBSI within 48 hours of admission
were enrolled. When there were multiple KpBSI
episodes only the first was included. We collected patients
data on age, sex, underlying disease, site of infection,
laboratory findings, microbiologic characteristics and
treatment outcomes. To assess treatment outcomes we
investigated 30-day mortality. This study was approved
by the institutional review board of Seoul National
University Hospital (IRB No. H-1010-062-336) and
Seoul National University Bundang Hospital (IRB No. B-0910/086-004) according to the Helsinki Declaration.
Community-onset KpBSI was defined as KpBSI
occurring within 48 hours of admission. HCA-KpBSI was
defined when a patient had one of the following medical
histories: (1) intravenous therapy at home or in an
outpatient clinic within the previous 30 days; (2) renal
dialysis in a hospital or clinic within the previous 30 days;
(3) hospitalization for 2 or more days within the
previous 90 days; (4) residence in a nursing home or
longterm care facility for 2 or more days . Patients without
any of these factors were classified as CA-KpBSI.
Biliary tract disease was defined when one or more
complicated biliary stone was present, or there was a
structural biliary abnormality due to benign or
malignant disease. Chronic liver disease referred to chronic
hepatitis and liver cirrhosis due to any cause. Charlsons
weighted index of co-morbidity and the Pitt bacteremia
score were used to evaluate the severities of underlying
disease and of acute illness, respectively [23,24]. Shock
was defined as a decrease in systolic blood pressure to
90mmHg or less, or a decrease of at least 40mmHg
below baseline blood pressure despite adequate fluid
resuscitation . An absolute neutrophil count of less
than 500/mL was defined as neutropenia. Polymicrobial
infection was defined when any pathogen other than K.
pneumoniae was isolated from blood culture at the same
time as the K. pneumoniae, and the isolated pathogen
also had clinical significance. Infection focus was
assessed clinically by attending physician in accordance
with site of isolation of K. pneumoniae.
The empirical antimicrobial therapy was defined as the
initial antibiotic choice before the results of blood
culture and antimicrobial susceptibility tests were available,
and the definitive antimicrobial therapy was defined as
the antibiotic choice after the report of microbiologic
tests. K. pneumoniae which was not susceptible to either
cefotaxime or ceftazidime was considered as suspected
extended-spectrum beta-lactamase (ESBL) producing
K. pneumoniae. Antimicrobial therapy was considered
as inappropriate when the treatment regimen did
not include any antibiotic active in vitro. In addition 3rd
generation cephalosporin monotherapy for suspected
ESBL-producing K. pneumoniae was considered
inappropriate, regardless of the results of antibiotic
All isolates were defined by BacT/ALERT FA and FN
(bioMerieux, Durham, North Carolina). Antimicrobial
susceptibility was identified by disk diffusion tests from
Table 1 Clinical characteristics of community-acquired and
healthcare-associated infections in patients with
communityonset Klebsiella pneumoniae bloodstream infection
Data indicate no. (%) of patients. WIC, weighted index of co-morbidity;
CA-KpBSI, community-acquired Klebsiella pneumoniae bloodstream infection;
HCA-KpBSI, healthcare-associated Klebsiella pneumoniae bloodstream infection.
a Others were one appendicitis, one pericarditis and two periodontitis.
b 52 patients were excluded from the analysis (15 patients were transferred to
other hospitals and 37 died before the culture results were available).
Age (years) (mean SD)
Chronic liver disease
Biliary tract disease
Chronic kidney disease
Solid organ transplantation
Charlsons WIC (3)
Primary infection site
Skin and soft tissue
Central nervous system
Pitt bacteremia score (4)
Shock at presentation
Neutropenia at presentation
Initial antimicrobial regimen
1st generation cephalosporin
3rd generation cephalosporin
2003 to 2006, and by Microscan WalkAway-96 (Siemens
Healthcare Diagnostics, Deerfield, Illinois) from 2007 to
2008, using the criteria of the Clinical and Laboratory
Standards Institute (CLSI; formerly, National Committee
for Clinical Laboratory Standards) guidelines. For the
available suspected ESBL-producing K. pneumoniae
isolates, ESBL production was determined by the double
disk synergy test according to the CLSI performance
Students t-test was used to compare continuous variables
and the 2 test or Fishers exact test was used to compare
categorical variables. To identify independent risk factors
for 30-day mortality, a stepwise logistic regression model
was used. Risk factors with a p value <0.10 in the
univariate analysis for 30-day mortality were included in the
initial model, and forward stepwise selection was performed
to develop the final model. We included the Pitt
bacteremia score instead of shock and, the Charlsons
weighted index of co-morbidity instead of underlying
diseases to avoid data overlap in the multivariate analysis.
p <0.05 was considered statistically significant. PASW for
Windows (version 18 software package; SPSS Inc.,
Chicago, IL, USA) was used for all analyses.
Demographics and underlying diseases
592 patients with community-onset KpBSI were
identified in the 6-year period. Of these, 553 (93%) were
analyzed, because 34 patients were lost to follow-up and
medical record was not available in 5 patients. Of the 553
patients with community-onset KpBSI, 313 (57%) were
classified as HCA-KpBSI and 240 (43%) as CA-KpBSI.
The mean age of the 553 patients was 61 years (median:
63 years, range: 18103), and 348 (63%) of the patients
were male. Solid tumor was the most common
underlying disease (238 patients, 43%). 145 (26%) patients had
diabetes mellitus and 123 (22%) had chronic liver disease.
The demographics and underlying diseases of
HCAKpBSI and CA-KpBSI are listed in Table 1. Solid tumor
(58% vs. 24%; p <0.001), hematologic malignancy (7% vs.
2%; p = 0.002) and chronic liver disease (27% vs. 16%;
p = 0.003) were more common in HCA-KpBSI than in
CA-KpBSI. Diabetes mellitus (31% vs. 23%; p = 0.031)
was more common in CA-KpBSI than in HCA-KpBSI.
Primary sites of infection and treatment outcomes
The pancreatobiliary tract was the most common site of
infection (184 cases, 33%). Liver (108, 20%) and primary
bacteremia (unknown focus) (73, 13%) were also
frequent sites of infection. Initially 156 (28%) patients
presented shock and 45 (8%) had neutropenia. 40 (7%)
patients of the 553 patients were treated with
inappropriate empirical antimicrobial therapy. After
excluding 52 of the 553 patients (15 were transferred to
other hospitals and 37 died before the culture results
were reported), 14 of the remaining 501 patients (3%)
were found to have been treated with inappropriate
definitive antimicrobial therapy.
The primary sites of infection and treatment outcomes
of HCA-KpBSI and CA-KpBSI are also compared in
Table 1. Peritonitis (15% vs. 5%; p <0.001) and primary
bacteremia (17% vs. 9%; p = 0.007) were more common
in HCA-KpBSI than in CA-KpBSI. On the other hand,
liver abscess (28% vs. 13%; p <0.001) was more frequent
in CA-KpBSI than in HCA-KpBSI. Initial shock (32% vs.
23%; p = 0.015) and neutropenia (13% vs. 1%; p <0.001)
were more common in HCA-KpBSI than in CA-KpBSI.
The 30-day mortality of HCA-KpBSI was higher than
that of CA-KpBSI (22% vs. 11%; p = 0.001).
48 of the 553 isolates (9%) were not susceptible to
ciprofloxacin and 37 isolates (7%) were not susceptible to either
cefotaxime or ceftazidime. Of these 37 isolates, 27 were
available for ESBL confirmatory tests and we performed
the double disk synergy test on them. Eighteen were
confirmed as producing ESBL. The antimicrobial
susceptibilities of HCA-KpBSI and CA-KpBSI are compared in
Table 2. A significantly higher proportion of the
HCAKpBSI than of the CA-KpBSI was resistant to tested
antimicrobial agents other than imipenem and amikacin.
Risk factors for 30-day mortality
The results of the univariate analyses of risk factors for
30-day mortality are shown in Table 3. High Charlsons
weighted index of co-morbidity was a risk factor (odds
ratio [OR], 2.86; 95% confidence interval [CI], 1.83-4.48)
and, when we analyzed each underlying disease, solid
tumor (OR, 3.32; 95% CI, 2.09-5.28) and hematologic
malignancy (OR, 3.52; 95% CI, 1.58-7.84) also turned
out to be significant risk factors. Infections of unknown
origin (OR, 3.71; 95% CI, 2.17-6.34) and respiratory
infections (OR, 3.38; 95% CI, 1.76-6.48) developed more
frequently in non-survivors than in survivors. In
contrast, liver abscess (OR, 0.11; 95% CI, 0.03-0.35) and
pancreatobiliary infection (OR, 0.50; 95% CI, 0.30-0.84)
were more common in survivors than in non-survivors.
In addition, high Pitt bacteremia score (OR, 8.04; 95%
CI, 4.87-13.28), neutropenia at initial presentation (OR,
4.48; 95% CI, 2.37-8.46), inappropriate empirical
antimicrobial therapy (OR, 2.46; 95% CI, 1.22-4.96),
polymicrobial infection (OR, 2.30; 95% CI, 1.34-3.94) and
healthcare-associated infection (OR, 2.27; 95% CI,
1.413.68) were risk factors in univariate analyses. There
was no significant difference in rates of antimicrobial
resistance to ciprofloxacin (7.0% in survivors vs. 9.3%
in non-survivors; p = 0.440) and extended-spectrum
cephalosporin (6.4% in survivors vs. 8.2% in
nonsurvivors; p = 0.499) between survivors and
From the multivariate logistic regression analysis,
significant risk factors for 30-day mortality were high (3)
Charlsons weighted index of co-morbidity (adjust odds
ratio [aOR], 3.23; 95% CI, 1.88-5.57), high (4) Pitt
bacteremia score (aOR, 8.43; 95% CI, 4.70-15.11),
neutropenia (aOR, 2.60; 95% CI, 1.24-5.48), polymicrobial
infection (aOR, 2.36; 95% CI, 1.21-4.60) and inappropriate
empirical antimicrobial therapy (aOR, 2.43; 95% CI,
1.07Table 2 Comparison of the antimicrobial susceptibility of community-acquired (CA) and healthcare-associated (HCA)
Klebsiella pneumoniae bloodstream infection (KpBSI)
Piperacillin plus tazobactam
Data indicate number of non-susceptible isolates/total number of tested isolates (%).
T, total number of tested isolates; ESBL, extended-spectrum beta-lactamase.
a 5 isolates among the CA-KpBSI were available for ESBL confirmatory tests and 14 among the HCA-KpBSI.
Table 3 Risk factors for 30-day mortality among patients with community-onset Klebsiella pneumoniae bloodstream
infection in univariate analysis
5.52). Liver abscess (aOR, 0.17; 95% CI, 0.05-0.58) and
pancreatobiliary tract infection (aOR, 0.42; 95% CI,
0.230.79) were found to be protective factors (Table 4). HCA
infection was not an independent risk factor for mortality
in multivariate analysis (aOR, 1.27; 95% CI, 0.70-2.30).
In a previous study, we demonstrated that nosocomial
KpBSI was different from CA- KpBSI . However, the
healthcare system has changed dramatically and this
simple dichotomy is no longer appropriate for KpBSI in
the current clinical setting. In this study we showed that
HCA-KpBSI accounted for over 50% of
communityonset KpBSI and HCA-KpBSI had different clinical
characteristics from CA-KpBSI in terms of underlying
disease, infection focus, antimicrobial susceptibility and
treatment outcome. To our knowledge, this is the largest
multicenter study comparing the clinical characteristics
of HCA-KpBSI and CA-KpBSI [11,12].
Cancer was the most common associated condition in
HCA-KpBSI. In contrast, diabetes mellitus was the most
common associated condition in CA-KpBSI. The
distribution of underlying disease in HCA-KpBSI was similar
to that in nosocomial KpBSI, except for the frequency of
chronic liver disease. While we found previously that the
frequency of this disease did not differ between
CAKpBSI and nosocomial KpBSI , it was more common
in HCA-KpBSI than in CA-KpBSI (27% vs. 16%; p =
0.003) in the present study. The latter finding is similar
to that of a study performed in Taiwan, although in the
Taiwanese study the difference was not statistically
significant (liver cirrhosis in HCA-KpBSI [14.0%] vs.
CAKpBSI [10.6%]; p = 0.339) .
The primary site of infection was identified in 87% of
community-onset KpBSI. The most common source was
the pancreatobiliary tract (33%), followed by liver abscess
(20%). Liver abscess was more frequent in CA-KpBSI
than in HCA-KpBSI. Compared to nosocomial KpBSI, in
which liver abscess was very rare (0% to 2%) [11,14,18],
HCA-KpBSI was quite frequently associated with liver
abscess (13%). Peritonitis was fairly frequent (>10%),
more so in HCA-KpBSI than in CA-KpBSI in our
analysis; in contrast Wu et al. found only a few (<5%) of
intra-abdominal infection and no difference in frequency
between HCA-KpBSI and CA-KpBSI . Our higher
frequency of peritonitis may be due to the prevalence of
chronic liver disease caused by hepatitis B or C virus in
Korea, which increases the occurrence of spontaneous
bacterial peritonitis [27,28].
More of the HCA-KpBSI isolates than of the
CAKpBSI isolates were resistant to antimicrobial agents.
Charlson's WIC (3)
Pitt bacteremia score (4)
Inappropriate empirical antimicrobial therapy
Data indicate no. (%) of patients.
WIC, weighted index of co-morbidity; OR, odds ratio; CI, confidence interval.
Table 4 Significant risk factors for 30-day mortality among community-onset Klebsiella pneumoniae bloodstream
infection in multivariate analysis
Over 10% of the former were not susceptible to
ciprofloxacin and 9% were not susceptible to one of the
extended-spectrum cephalosporin. Although frequent
antimicrobial resistance could affect the inadequacy of
the initial choice of antimicrobial agent, there was no
difference in rate of inappropriate empirical
antimicrobial therapy between the HCA-KpBSI and the CA-KpBSI
(6% vs. 8%; p = 0.266). This result could have arisen
because in cases of healthcare-associated infection
clinicians may have taken into account frequencies of
antimicrobial resistance when selecting the initial
antibiotic. Actually, fewer HCA-KpBSI than CA-KpBSI
(6% vs. 10%; p = 0.088) were started on quinolones while
more were started on piperacillin-tazobactam (Table 1).
Regarding empirical treatment, the proportion of
patients treated inappropriately (7.2% of total patients)
was much lower than was observed in other studies,
which showed that over 20% of patients were treated
inappropriately [9,29,30]. This discrepancy might have been
the result of differences in the definition of appropriate
empirical treatment, because the definition we used was
less strict than those in other studies [31-33]. In addition,
broad-spectrum antimicrobial agents, such as 3rd
generation cephalosporins or carbapenems, were frequently
used empirically in our study (84.6% in CA infection,
74.7% in HCA infection). Considering that only 3.3% of
organisms in CA infection and 9.3% of organisms in HCA
infection were non-susceptible to extended-spectrum
cephalosporins, the use of broad-spectrum antimicrobial
agents also might have influenced the lower proportion of
patients with treated inappropriately. However, other East
Asian studies of K. pneumoniae bacteremia also
demonstrated a similar proportion of patients treated with
inappropriate empirical therapy [12,14,18].
There was a significant difference of 30-day mortality
rate between HCA-KpBSI and CA-KpBSI in this study
(22% vs. 11%; p = 0.001). High Charlsons weighted index
of co-morbidity (3), high Pitt bacteremia score (4),
neutropenia, polymicrobial infection and inappropriate
empirical antimicrobial therapy were found to be
independent risk factors for mortality. However, HCA
infection itself was not a significant risk factor for
30day mortality in multivariate analysis. This finding is
consistent with the recent report from Taiwan and a
bloodstream infection study dealing with gram-negative
bacteria [9,12]. There are several explanations for this
result. First, in our study, underlying disease and acute
illness, which are classical risk factors for outcome of
infectious disease, may have been so severe as to have
attenuated the effect of HCA infection on mortality
[23,24,34]. Second, whether the infection focus was
removable, and was or was not removed, may have
affected mortality more than whether the infection was
HCA or not . Liver abscess and pancreatobiliary
infection can be classified as infections with removable
foci, as opposed to pneumonia or primary bacteremia. In
our study, percutaneous or internal drainage was
performed in cases of liver abscess and obstructive
pancreatobiliary infection, and these kinds of infection were
found to be independent protective factors for mortality,
as in the previous studies [11,14,18]. Third, as indicated
by Friedman et al., the definition of HCA infection
which we used in this study may have been excessively
broad since the definition was based on the U.S. medical
system . Unlike the U.S., South Korea has started a
national health insurance system in 1977 and extended
it nationwide in 1982. Consequently, there is a tendency
for more people to access the medical system and be
classified as HCA infection in Korea. Such national
differences in healthcare systems could complicate the
unambiguous identification of patients with HCA
infections so as to be able to evaluate the actual effect of
HCA infection on mortality. Therefore we need further
studies using a more accurate and consistent definition
of HCA infection that accords better with variations in
Our study had several limitations. First, there was a
potential bias because it was performed retrospectively.
Second, it was conducted in tertiary-care and
universityaffiliated hospitals and there was a large proportion of
cancer patients in both the CA-KpBSI and HCA-KpBSI
groups. Hence, we cannot extrapolate our result to
community-based institutions. Third, we did not
evaluate the attributable mortality due to KpBSI, so that
some of the deaths in our study may not have been
related to KpBSI. However, efforts to designate outcomes
as attributable to infection are often subjective and
inconsistent. We therefore employed an unambiguous
definition, namely 30-day mortality rate, for evaluating
treatment outcomes. Fourth, because we did not review
the patients previous exposure to antimicrobial agents,
we could not determine the influence of that factor on
the acquiring resistant organisms and treatment
outcome. Additionally, we did not collect data on the
variation of antimicrobial therapy, such as duration or
dosage; therefore, we could not take into account these
issues, which could affect the analysis of risk factors for
mortality. However, upon examining the mortality rate
in other studies, our data are comparable; therefore, the
regimen and duration of therapy we used were also
likely to be similar to others [12,14].
What clinicians actually want to know is that HCA
infection needs a specific work-up process or treatment.
Accordingly, our study can provide useful information.
First, we could see the difference of infection focus
according to the epidemiological category more clearly
by separating HCA infection and CA infection in
comparison to our previous report . Peritonitis is more
commonly associated with HCA infection than with CA
infection in the present study, while the frequency of
peritonitis in CA infection was relatively high (20.4%)
and was not different from that observed in nosocomial
infection in the previous study . However, when we
classified more precisely we could see that peritonitis
occurred in much lower frequency in true CA infection. In
addition, we could identify the infection focus of all but
8.8% of the patients with true CA infection (in
previously defined CA infection, 25.7% patients were
unidentified for infection focus) . Second, comparing the
resistance rate to antimicrobial agents in HCA infection
with CA infection can help clinicians choose an initial
antimicrobial agent in treating patients of each subset,
which means not only should we consider
broadspectrum antimicrobial agents in HCA infection but also
that we may not need to start broad-spectrum
antimicrobial agents, such as extended-spectrum
cephalosporins or carbapenems, in CA infection. Based on our
data, quinolone can be a drug of choice in treating true
CA-KpBSI. Finally, even though we showed many
differences between HCA infection and CA infection, we did
not find HCA infection to be an independent risk factor
for mortality in KpBSI, which confirmed that the already
known risk factors for mortality (severity of underlying
disease, inadequate empirical therapy and severity of
acute illness) are more important predictors of mortality
in KpBSI [12,14].
HCA-KpBSI represented over half of community-onset
KpBSI and had different characteristics from CA-KpBSI.
In HCA-KpBSI, underlying diseases were more severe,
primary bacteremia and peritonitis were more common
and resistance to antimicrobials was more frequent than
in CA-KpBSI. HCA-KpBSI had higher 30-day mortality
than CA-KpBSI, but HCA infection was not an
independent risk factor for 30-day mortality. In present-day
clinical circumstances, HCA-KpBSI should be identified
as a distinctive category and be approached in a different
way from CA-KpBSI.
There are no potential conflicts of interest for any authors.
All authors conceived of the study. YHJ, MJL, HYS collected the data. KHS
and YHJ carried out data analysis and interpretation. NHK, JHH, JYP, PGC,
WBP, ESK, SWP, KUP, HBK, NJK, ECK and MDO carried out data interpretation.
YHJ and KHS drafted the manuscript. All authors have read and approved
the final manuscript.
This study was supported by grant No. 11-2009-012 from the Seoul National
University Bundang Hospital Research Fund. This study was presented in part
at the 49th annual meeting of the Infectious Diseases Society of America,
Boston, 2011 (Abstract number 990).
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