Group Title: BMC Infectious Diseases
Title: Bacteremia in hospitalized patients with human immunodeficiency virus: A prospective, cohort study
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Title: Bacteremia in hospitalized patients with human immunodeficiency virus: A prospective, cohort study
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Language: English
Creator: Afessa, Bekele
Morales, Ian
Weaver, Bethany
Publisher: BMC Infectious Diseases
Publication Date: 2001
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Abstract: BACKGROUND:Bacterial infections complicate the course of patients with human immunodeficiency virus infection. The purpose of this study was to describe the bacterial pathogens causing blood stream infection, identify the risk factors for the development of blood stream infection and determine the impact of blood stream infection on the outcome of patients infected with human immunodeficiency virus.METHODS:The incidence, etiology, risk factors and outcome of bacterial blood stream infection were prospectively determined in 1,225 consecutive hospitalizations of adults with human immunodeficiency virus infection.RESULTS:Blood stream infection occurred in 88 hospitalizations (7%); 73 of 89 infections (82%) were community acquired. The most commonly isolated gram-positive organism was Streptococcus pneumoniae (21); gram-negative, Escherichia coli (14). Blood stream infection was detected in 8% of African Americans and 22% of Hispanics compared with 2% of whites (P = 0.0013). Patients with blood stream infection had higher white blood cell counts (median, 6.5 vs. 4.9 × 109/L; P = 0.0002) and mortality (18% vs. 4%; P < 0.0001) than patients without infection.CONCLUSIONS:In patients with human immunodeficiency virus, blood stream infection is associated with an increased mortality rate. Recognition of the incidence, etiology, and risk factors of blood stream infection in patients with human immunodeficiency virus infection could lead to measures that reduce the increased mortality.
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Research article
Bacteremia in hospitalized patients with human immunodeficiency
virus: A prospective, cohort study
Bekele Afessa*1,2,3, Ian Morales2,3 and Bethany Weaver2,4

Address: 'From the Division of Pulmonary and Critical Care, University of Florida Health Science Center, Jacksonville, Florida, USA,
2Department of Internal Medicine, University of Florida Health Science Center, Jacksonville, Florida, USA, 3Current affiliations Division of
Pulmonary and Critical Care Medicine and Internal Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN USA and 4Current affiliations
Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington, Box 35931, Seattle, WA 98104, USA
E-mail: Bekele Afessa* afessa.bekele@mayo.edu; Ian Morales morales.ian@mayo.edu; Bethany Weaver bethanyg@u.washington.edu
*Corresponding author


Published: 7 September 2001 Received: 22 June 2001
BMC Infectious Diseases 2001, 1:13 Accepted: 7 September 2001
This article is available from: http://www.biomedcentral.com/1471-2334/l/1 3
2001 Afessa et al; licensee BioMed Central Ltd. Verbatim copying and redistribution of this article are permitted in any medium for any non-com-
mercial purpose, provided this notice is preserved along with the article's original URL. For commercial use, contact info@biomedcentral.com





Abstract
Background: Bacterial infections complicate the course of patients with human
immunodeficiency virus infection. The purpose of this study was to describe the bacterial
pathogens causing blood stream infection, identify the risk factors for the development of blood
stream infection and determine the impact of blood stream infection on the outcome of patients
infected with human immunodeficiency virus.
Methods: The incidence, etiology, risk factors and outcome of bacterial blood stream infection
were prospectively determined in 1,225 consecutive hospitalizations of adults with human
immunodeficiency virus infection.
Results: Blood stream infection occurred in 88 hospitalizations (7%); 73 of 89 infections (82%)
were community acquired. The most commonly isolated gram-positive organism was Streptococcus
pneumoniae (21); gram-negative, Escherichia coli (14). Blood stream infection was detected in 8% of
African Americans and 22% of Hispanics compared with 2% of whites (P = 0.0013). Patients with
blood stream infection had higher white blood cell counts (median, 6.5 vs. 4.9 x 109/L; P = 0.0002)
and mortality (18% vs. 4%; P < 0.0001) than patients without infection.
Conclusions: In patients with human immunodeficiency virus, blood stream infection is associated
with an increased mortality rate. Recognition of the incidence, etiology, and risk factors of blood
stream infection in patients with human immunodeficiency virus infection could lead to measures
that reduce the increased mortality.



Background tions. These factors include abnormalities in humoral
The importance of bacterial infections that complicate and cell-mediated immunity, phagocytic cell dysfunc-
the clinical course of patients with human immunodefi- tion, and skin and mucous membrane defects [3]. The
ciency virus (HIV) infection has been recognized since presence of neutropenia [4,5] use of central venous cath-
the beginning of the AIDS epidemic [1,2]. Several factors eters [4,6], low CD4+ lymphocyte count, and intravenous
predispose patients with HIV infection to bacterial infec- drug use [6] are cited as risk factors for bacteremic infec-








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tions in patients with HIV infection. Bacterial infections
are responsible for the immediate cause of death of up to
30o% of patients with HIV infection [7]. The purpose of
this study was to describe the bacterial pathogens caus-
ing blood stream infection, identify the risk factors for
the development of blood stream infection, and deter-
mine the impact of blood stream infection on the out-
come of hospitalized patients with HIV.

Methods
This prospective, observational study included 1,225
consecutive hospital admissions of 599 adults with HIV
infection treated at the University Medical Center, Jack-
sonville, Florida, from April 1995 through March 1998.
All adults with HIV infection who were admitted to the
hospital were included in the study. The University Med-
ical Center is a 528-bed, inner-city teaching hospital af-
filiated with the University of Florida. Because of the
hospital's inner-city location, most of the patients were
African American. The need for informed consent was
waived by the institutional review board of the hospital.

The isolation of a bacterium in 1 or more blood cultures
was diagnostic of bacterial blood stream infection. Blood
isolates of coagulase-negative staphylococci, Corynebac-
terium species, Bacillus species, Propionibacterium spe-
cies, Peptostreptococcus species, Clostridium species,
and unidentified Gram-positive rods were considered
contaminated if a single blood culture yielded the organ-
ism or the clinician did not initiate treatment, consider-
ing it not a true infection. Mycobacterial infections were
excluded from the study. The place of acquisition of the
blood stream infection was defined as nosocomial if the
infection developed after 48 hours of hospitalization or
within 14 days of previous hospitalization. We collected
data on age, sex, race, exposure category for HIV infec-
tion, place of acquisition, white blood cell count, CD4+
lymphocyte count, worst Acute Physiology and Chronic
Health Evaluation (APACHE) II score within 24 hours of
hospital admission, presence of blood stream infection,
intensive care unit admission status, length of hospital
stay, and in-hospital mortality. The source of the blood
stream infection was identified by the isolation of the
same pathogenic organism from both the source and the
blood. The APACHE II score and predicted mortality
rate for each hospital admission were calculated [8]. The
standardized mortality ratio was determined by dividing
the actual mortality by the predicted mortality. For the
purpose of this study, each admission was analyzed inde-
pendently.

StatView 5.0 computer software (SAS Institute, Cary,
NC) was used for statistical analysis. Each mean was ex-
pressed with its standard deviation. Comparisons be-
tween groups were made using logistic regression


analysis and Student t, Mann-Whitney U, X2, and Fisher
exact tests. When available, the continuity-corrected P
values were used for X2 analysis. P values less than 0.05
were considered significant.

Results
Table 1 provides demographic, exposure category, and
health status data on 1,225 hospital admissions of 599
patients with HIV infection. Because some individuals
were admitted more than once during the study period,
in this report the word patient does not necessarily mean
1 unique individual. Thirty-four percent of the African
Americans and 67% of the Hispanics had a history of in-
jection drug use compared with 20% of the whites (P <
o.oool).

Table I: Demographic Characteristics.


Characteristic


Value


Age, mean SD, y
Sex
Male
Female


African American
White
Hispanic
Exposure category
Injection drug use
Heterosexual contact
Homosexual contact
Commercial sex work and injection drug
use
Homosexual contact and injection drug
use
Commercial sex work
Blood transfusion
Needle stick
Unidentified
CD4 lymphocyte count, mean SD
(median), x 109/L
APACHE II score, mean SD (median)


38.2 + 8.9

754 (62)
471 (38)

1,026 (84)
190 (16)
9(< I)

333 (27)
194 (16)
138 (I 1)
32 (3)

30(2)

29 (2)
22 (2)
I (<1)
446 (36)
0.159 + 0.223 (0.060)

15 7(14)


APACHE, Acute Physiology and Chronic Health Evaluation; HIV,
human immunodeficiency virus; SD, standard deviation. aValues are
number (percentage) unless otherwise indicated.



In the 1,225 admissions, 88 patients (7%) had 89 epi-
sodes of blood stream infection. Of these 89 infections,
73 (82%) were community acquired and 16 (18%) were
nosocomial. Twenty-one of the 345 admissions (6%)
during the first year of the study had blood stream infec-
tion compared with 35 of 435 admissions (8%) during
the second year and 32 of 445 admissions (7%) during
the third year (P = 0.5748). The sources of bacteremia


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Table 2: Bacterial Pathogens Causing Blood Stream Infection in
Hospitalized Patients With HIV Infection


Pathogen


Gram-negative bacteria
Escherichia coli
Pseudomonas aeruginosa
Salmonella typhi
Enterobacter cloacae
Acinetobacter baumanii
Proteus vulgaris
Aeromonas hydrophila
Haemophilus influenzae
Pseudomonas stutzeri
Proteus mirabilis
Klebsiella pneumoniae
Gram-positive bacteria
Streptococcus pneumoniae
Staphylococcus aureus
Enterococcus species
Streptococcus viridans
Coagulase-negative Staphylococcus
Streptococcus equisimilis
Group C Streptococcus species
Nonhemolytic Streptococcus species


Community
acquired, no. Nosoco-
mial, no.
(n = 73) (n = 16)


HIV, human immunodeficiency virus.




were identified in 52 patients (59%) and included pneu-
monia in 33, urinary tract infection in 12, peritonitis in 2,
and cellulitis, pancreatitis, central venous catheter,
cholangitis, and arthritis in 1 each. In 1 patient, 2 organ-
isms, Salmonella typhi and Klebsiella pneumoniae, were
isolated from the blood during the same hospitalization;
both were community acquired. The pathogens causing
blood stream infection are listed in Table 2. Six patients
had 2 episodes of blood stream infection during the
study period, all during different hospitalizations. One
patient had 2 episodes of Pseudomonas aeruginosa bac-
teremia and another patient had 2 episodes of S typhi
bacteremia.

There were no significant differences in age, sex, and risk
factors for HIV infection between patients with and with-
out blood stream infection (Table 3). The median CD4+
lymphocyte count for injection drug users was 0.08 x
1o9/L compared with o.o6 x 1o9/L for noninjection drug
users (P = 0.0042). The incidence of blood stream infec-
tion in African Americans and Hispanics was higher than
in whites (Table 3). The CD4+ lymphocyte count was
similar and the APACHE IT score and white blood cell


count higher in patients with blood stream infection
compared with those without blood stream infection
(Table 3). In patients with blood stream infection, 78%
had a CD4+ lymphocyte count less than 0.2 X 109/L com-
pared with 74% of the patients without blood stream in-
fection (P = 0.5649). The predicted mortality rate of
patients with blood stream infection was higher than
that of patients without blood stream infection (37% vs.
21%; P < o.oooi). Twenty-six percent of the patients
with blood stream infection had a white blood cell count
less than 4 x 1o9/L compared with 36% of the patients
without blood stream infection (P = 0.0810).

The differences in the length of hospital stay, intensive
care unit admission rate, and in-hospital mortality be-
tween patients with and patients without blood stream
infection are listed in Table 4. Compared with patients
without blood stream infection, the in-hospital mortality
and intensive care unit admission rates of patients with
blood stream infection were higher and their length of
hospital stay longer. The standardized mortality ratios of
patients with and without blood stream infection were
0.486 and 0.213, respectively. Multiple logistic regres-
sion analysis using a model consisting of mortality as a
dependent variable and APACHE II score and presence
of blood stream infection as independent variables
showed that both blood stream infection (odds ratio,
2.29; 95% CI, 1.13-4.62) and APACHE II score (odds ra-
tio, 1.18; 95% CI, 1.14-1.23) were independently associ-
ated with mortality. Among patients with blood stream
infection, survivors had a lower APACHE II score than
nonsurvivors (median, 17 vs. 27.5; P < o.oool), but did
not significantly differ in CD4+ lymphocyte count (medi-
an, 0.077 vs. 0.011 x 1o9/L; P = 0.0574). Two of the 34
patients (6%) with gram-negative blood stream infection
died compared with 14 of 54 patients (26%) with gram-
positive blood stream infection (P = 0.0366). The mor-
tality associated with each pathogen causing blood
stream infection is listed in Table 5. Among the 88 pa-
tients with blood stream infection, multiple logistic re-
gression analysis using a model of mortality as a
dependent variable and APACHE II score, CD4+ lym-
phocyte count, and place of acquisition of the infection as
independent variables showed that higher APACHE II
scores (odds ratio, 1.25; 95% CI, 1.12-1.4o) and nosoco-
mial acquisition (odds ratio, 5.85; 95% CI, 1.25-27.31),
but not CD4+ lymphocyte count (odds ratio, 1.oo; 95%
CI, o.99-1.oo), were independently associated with
mortality. The intensive care unit admission rate of pa-
tients with community-acquired blood stream infection
was similar to that of patients with nosocomial blood
stream infection (19% vs. 44%; P = 0.0820). The median
length of hospital stay of patients with community-ac-
quired blood stream infection was 5 days compared with
8.5 days for patients with nosocomial blood stream in-


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Table 3: Differences in Age, Sex, Race, Exposure Category, CD4+ Lymphocyte Count, and APACHE II Score


Blood stream infection


Characteristic


Present (n = 88)


Age, mean SD, y
Sex
Male
Female
Race
African American
White
Hispanic
Exposure category
Injection drug use
Heterosexual contact
Homosexual contact
Commercial sex work and
injection drug use
Homosexual contact and
injection drug use
Commercial sex work
Blood transfusion
Needle stick
Unidentified
CD4 lymphocyte count,
mean SD (median), x 109/L
White blood cell count,
mean SD (median), x 109/L
APACHE II score,
mean SD (median)


38.3 + 9.3

50(7)
38 (8)

83 (8)
3 (2)
2 (22)

23 (7)
19 (10)
3 (2)
2 (6)

2 (7)

2 (7)
I (5)
0 (0)
36(8)
0.173 0.278 (0.059)

9.0 6.6 (6.5)

19.8 + 7.9 (18)


Absent (n = 1, 137)


38.2 + 8.9

704 (93)
433 (92)

943 (92)
187 (98)
7 (78)

310 (93)
175 (90)
135 (98)
30 (94)

28 (93)

27 (93)
21 (95)
1 (100)
410 (92)
0.158 + 0.218 (0.060)

6.3 4.6 (4.9)

14.3 6.6 (13)


APACHE, Acute Physiology and Chronic Health Evaluation; SD, standard deviation. aValues are number (percentage) unless otherwise indicated.


fection (P = 0.0477). The mortality rate of patients with
blood stream infection was 6% during the third year of
the study compared with 14% and 31% during the first
and second years, respectively (P = 0.0247).

Table 4: Differences in Length of Hospital Stay, ICU Admission
Rate, and In-hospital Mortality

Blood stream infection


Characteristic


Length of hospital stay,
mean SD (median), d
ICU admission
In-hospital mortality


Present Absent
(n = 88) (n = 1,137)


8.7 9.3 (6)
21 (24)
16 (18)


6.0 6.3 (4)
112 (10)
51 (4)


ICU, intensive care unit; SD, standard deviation. aValues are number
(percentage) unless otherwise indicated.


Discussion
This study describes the incidence of bacterial blood
stream infection as well as its causative pathogens, risk
factors for its development, and its impact on outcome in
hospitalized patients with HIV. Blood stream infection
developed in 7% of the patients; of these infections, 82%
were community acquired and 18% were nosocomial.
The incidence rate of blood stream infection was higher
in African Americans and Hispanics compared with
whites. There were no significant differences in sex, age,
and CD4+ lymphocyte count between patients with and
patients without blood stream infection. The APACHE II
score and white blood cell count of patients with blood
stream infection were higher than those of patients with-
out blood stream infection. The mortality and ICU ad-
mission rates of patients with blood stream infection
were higher and their length of hospital stay longer than
those of patients without blood stream infection. Among
patients with blood stream infection, the mortality rate


0.9261
0.4045


0.0013



0.423 I1


0.6967

0.0002

< 0.0001


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of the community-acquired group was lower than that of
the nosocomial group.

Table 5: In-hospital Mortality Associated With Pathogens Caus-
ing Blood Stream Infection in Patients With HIV Infection


Survivors,
no.
(%) (n = 72)


Pathogen


Gram-negative bacteria
Escherichia coli
Pseudomonas aeruginosa
Salmonella typhi
Enterobacter cloacae
Acinetobacter baumanii
Proteus vulgaris
Aeromonas hydrophila
Haemophilus influenzae
Pseudomonas stutzeri
Proteus mirabilis
Klebsiella pneumoniae and S typhi
Gram-positive bacteria
Streptococcus pneumoniae
Staphylococcus aureus
Enterococcus species
Streptococcus viridans
Streptococcus equisimilis
Coagulase-negative Staphylococcus
Group C Streptococcus species
Nonhemolytic Streptococcus species


32 (94)
14 (100)
6 (100)
5 (100)
I (50)
1(100)
1(100)
1(100)
1(100)
1(100)
0
1 (100)
40 (74)
18 (86)
7(58)
7(87)
6(75)
1 (100)
I (so)
0
0


Nonsurvivors,
no.
(%) (n = 16)


2 (6)
0
0
0
1 (50)
0
0
0
0
0
1 (100)
0
14 (26)
3 (14)
5(42)
1 (13)
2(25)
0
I (50)
1 (100)
1 (100)


HIV, human immunodeficiency virus.




Bacteremia is more common in hospitalized HIV-posi-
tive patients than in HIV-negative patients [9]. The inci-
dence of nonmycobacterial bacteremias in hospitalized
patients with HIV ranges from 2% to 9% [10-12]. Most
blood stream infections in patients with HIV are commu-
nity acquired [13,14]. In developed countries, the inci-
dence rate of HIV-associated bacteremia has declined
after the introduction of highly active antiretroviral ther-
apy (HAART) [14,15]. In the present study, the incidence
of blood stream infection among hospitalized patients
with HIV was 7%, and most of these infections were com-
munity acquired. Despite the availability of HAART dur-
ing the later period of our study, we did not find a decline
in the rate of bacteremia in our patient population. How-
ever, the mortality rate of the patients with blood stream
infection declined during the third year of the study, re-
flecting the potential benefit of HAART.

African American race, Hispanic race, and high APACHE
II score were found to be risk factors for blood stream in-
fection in hospitalized patients with HIV infection in the


present study. Because there were only few Hispanics in
the present study and the African Americans were more
likely than the whites to be injection drug users, we do
not think there is an independent association between
race and bacteremia. Previous studies have shown injec-
tion drug use to be a risk factor for bacteremia [6,14].
However, like the study by Tumbarello et al. [16], our
study did not find injection drug use to be a risk factor for
blood stream bacterial infection. The earlier stage of HIV
infection in the injection drug users in our study may ex-
plain their lower bacteremia rate. Neutropenia is report-
ed to be a risk factor for the development of bacterial
infection in patients with HIV infection [4-6,14,16].
However, in our study, neither the prevalence of leuko-
penia nor the total white blood cell count was lower in
patients with blood stream bacterial infection compared
with patients without blood stream bacterial infection.
In fact, the white blood cell count was higher in patients
with than in patients without bacterial blood stream in-
fection. Unlike other studies, which showed the CD4+
lymphocyte count to be low in HIV-positive patients with
blood stream bacterial infection [6,16], the CD4+ lym-
phocyte count did not differ between patients with and
patients without bacterial blood stream infection in the
present study. The lack of association between bactere-
mia and low CD4+ lymphocyte count or leukopenia in the
present study may reflect the earlier stage of HIV infec-
tion in our patient population.

Previous studies have shown the presence of central ve-
nous catheters to be a risk factor for bacterial blood
stream infection [4,6,11,14,16,17]. In the present study,
an intravascular catheter was the source of the blood
stream infection in only 1 patient; this was probably due
to infrequent use of central venous catheters and shorter
length of hospital stay. As in the study by Tumbarello et
al. [14], higher severity of illness, measured by APACHE
II score, was associated in the present study with the de-
velopment of bacterial blood stream infection.

The common sources of blood stream infection in pa-
tients with HIV infection include the lungs, skin, subcu-
taneous tissue, and intravascular catheters [12,13,18,19].
In the present study, the most common source of bacter-
emia was pneumonia.

Gram-positive bacteria are responsible for most of the
bacteremias in hospitalized HIV-positive patients [14].
More gram-positive than gram-negative organisms were
isolated from the blood stream of our subjects. Many
studies have shown Staphylococcus species to be the
most common isolates in blood [6,11,13,16,20]. In our
study Streptococcus pneumoniae was the most common
isolate. The rate of pneumococcal bacteremia is about
loo-fold higher in patients with than in patients without


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HIV infection [21]. Because most of the blood stream in-
fections were community acquired and the most com-
mon source of infection was pneumonia, Staphylococci
were less frequent than S pneumoniae and Escherichia
coli.

P aeruginosa is being recognized more frequently as
causing both community-acquired and nosocomial bac-
teremia in patients with HIV infection
[13,16,18,20,22,23]. Hospitalization, neutropenia, anti-
biotic therapy, steroid use, and low CD4+ lymphocyte
count are risk factors for P aeruginosa bacteremia in pa-
tients with HIV infection [22,24]. Previously, we report-
ed that P aeruginosa is the most common pathogen
causing bacterial pneumonia in our patients [25]. How-
ever, compared with pneumococcal pneumonia, Pseu-
domonas pneumonia is less likely to be associated with
bacteremia [25]. The annual incidence rate of P aerugi-
nosa infection in patients with HIV infection is estimated
to be 2.51 cases per o100 admissions [22]. P aeruginosa
has been reported to be the causative agent of 7.6% to
18% of bacteremias in hospitalized patients with HIV in-
fection [14,16,20]. In the present study, P aeruginosa
was responsible for 6% of the bacteremias.

In patients with HIV infection, although bacteremia in
general is more frequently associated with growth of
gram-positive pathogens, genitourinary sepsis is more
frequently related to the detection of gram-negative bac-
teria [26]. Our finding ofE coli to be the most common
gram-negative organism differs from findings in previ-
ous studies. In a recent study of blood stream infection of
hospitalized patients with HIV, E coli was not even men-
tioned among the common etiologic agents [14]. In the
present study a significant number of the patients with
blood stream infection were women, who are at higher
risk for genitourinary infection. The relatively high
number of women may explain the high rates of E coli
blood stream infection in our study.

The present study showed that the presentation with or
the development of blood stream infection in hospital-
ized patients with HIV leads to poor outcome, as evi-
denced by increased mortality, length of hospital stay,
and intensive care unit admission rate. Hospital mortal-
ity rates of HIV-positive patients with blood stream in-
fection range from 9% to 63% [6,9,11-14,16]. In the
present study, the hospital mortality rate of patients with
blood stream infection was 16%. Among patients with
blood stream infection, we found the association of in-
creased mortality with high APACHE II score and hospi-
tal acquisition of the infection, but not with low CD4+
lymphocyte count. Because nosocomial bacteremia is
likely to develop in patients with a complicated hospital
course and lead to multiple organ dysfunction, its associ-


ation with an increased mortality rate is not surprising.
Previous studies of HIV-positive patients with blood
stream infection have shown that a high APACHE II
score predicts an increased risk of death [14,27]. Al-
though we did not find a significant association between
mortality and CD4+ lymphocyte count, a previous study
showed that a low CD4+ lymphocyte count is associated
with increased mortality in patients with nosocomial
blood stream infection [27].

Our study has several limitations. The risk factors for
HIV infection were not identified in 36%, most probably
because of the health care providers' and patients' lack of
openness with regard to sexual activity. Because we were
unable to document the patients' antiretroviral therapy
and previous antimicrobial treatment or chemoprophy-
laxis, we could not assess their impact on the incidence,
etiology, and outcome of bacterial blood stream infec-
tion. In many patients, the source of the blood stream in-
fection was not identified. Finally, because the study was
limited to a single center, the results may not apply to
other patient populations.

Conclusions
Bacteremia occurs in 7% of adult patients with HIV in-
fection who require admission to the hospital. Most of
the bacteremias are community acquired. The most com-
mon gram-positive organism isolated from the blood
stream of patients with HIV infection is S pneumoniae,
and the most common gram-negative organism is E coli.
The APACHE II score of patients with blood stream in-
fection is higher than that of patients without blood
stream infection. The presence of blood stream infection
is associated with an increased mortality rate, length of
hospital stay, and intensive care unit admission rate.
Recognition of the incidence, etiology, and risk factors of
blood stream infection in patients with HIV infection can
lead to preventive and therapeutic measures that may re-
duce the associated increased mortality and morbidity.

Competing interests
None declared.

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