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infectious diseases
Nosocomial Infections in the
Neonatal Intensive Care Unit
Richard A. Polin, MD,*
Lisa Saiman, MD, MPH†
Objectives
After completing this article, readers should be able to:
1. List the primary pathogens involved in late-onset infections.
2. List the major risk factors for nosocomial sepsis.
3. Describe practices that can reduce the risk of nosocomial infections.
Introduction
Improvements in antenatal management and neonatal intensive care over the past 10 to 15
years have changed the prognosis for preterm infants. More than 85% of infants born at
25 weeks’ gestation now survive their preterm birth. This has resulted in a dramatic change
in the populations of infants occupying neonatal intensive care beds. The average length of
stay for a term or near-term infant who has surgical or respiratory problems is about
15 days; the length of stay for preterm infants born at 26 weeks’ gestation is more than
2 months. The duration of hospitalization is inversely related to gestational age.
The population of extremely low-birthweight (ELBW) infants who remain hospitalized
for extended periods of time (and who undergo numerous invasive procedures) is most
susceptible to nosocomial infections. Nosocomial infections are defined as those that occur
beyond 48 hours after birth and are caused by pathogens that are not maternally derived.
Such infections are 100 times more common than early-onset bacterial infections, which
are caused by pathogens acquired in utero or perinatally. Recent data from the National
Institute of Child Health and Human Development-sponsored “Neonatal Network”
indicated that 29% of infants born at 25 to 28 weeks’ gestation and 46% of infants born at
less than 25 weeks’ gestation experience a serious nosocomial infection during hospitalization in the NICU.
The morbidity and mortality from nosocomial infections
is enormous. In the United States, more than 2,000,000
nosocomial infections (in infants and adults) occur each year,
Abbreviations
and 50% to 60% are caused by resistant organisms. It has
been estimated that 9,600 to 20,000 patients die each year in
CONS:
coagulase-negative staphylococci
the United States from catheter-related bloodstream infecELBW:
extremely low-birthweight
tions. Nosocomial infections increase the costs of neonatal
ESBL:
extended-spectrum beta-lactamase-producing
intensive care, prolong hospitalization by several weeks, and
G-CSF: granulocyte colony-stimulating factor
are responsible for almost 50% of the deaths that occur
GM-CSF: granulocyte-macrophage colony-stimulating
beyond 2 weeks of age. Although the epidemiology of
factor
neonatal nosocomial infections is complex, both simple and
HICPAC: Healthcare Infection Control Practices
theoretical strategies can reduce the frequency of hospitalAdvisory Committee
acquired infections. This article discusses the epidemiology
IVIG:
intravenous immune globulin
and prevention of nosocomial infections in the neonatal
MRSA: methicillin-resistant Staphylococcus aureus
intensive care unit (NICU).
MSSA: methicillin-susceptible Staphylococcus aureus
NICU:
RSV:
VRE:
VREF:
neonatal intensive care unit
respiratory syncytial virus
vancomycin-resistant enterococci
vancomycin-resistant Enterobacter faecium
Epidemiology and Microbiology
Over the past 50 years, the epidemiology of pathogens
responsible for nosocomial infections in neonates has
changed dramatically. During the 1950s, Staphylococcus
*Professor of Pediatrics, Division of Neonatology, Department of Pediatrics, College of Physicians and Surgeons, Columbia
University; Director, Division of Neonatology, Children’s Hospital of New York Presbyterian, New York, NY.
†
Associate Professor of Clinical Pediatrics, Division of Infectious Disease, Department of Pediatrics, College of Physicians and
Surgeons, Columbia University, New York, NY.
NeoReviews Vol.4 No.3 March 2003 e81
infectious diseases nosocomial infections
Nosocomial Infections and
Infectious Pathogens in Patients in the
Neonatal Intensive Care Unit
aureus phage type 80/81 was the Table 1.
most common nosocomial pathogen in hospitalized infants. During
the 1960s, gram-negative bacilli,
including Pseudomonas aeruginosa,
Site of Infection
Common Pathogens
Less Common Pathogens
Klebsiella sp, and Escherichia coli,
became the most common pathoBloodstream/sepsis
CONS
Enterococci
gens. By the 1970s, coagulaseStaphylococcus aureus
Klebsiella sp
Pseudomonas aeruginosa Serratia marcescens
negative staphylococci (CONS)
Candida sp
Enterobacter sp
(predominantly S epidermidis) and
Malassezia sp
S aureus, including methicillinPneumonia
CONS
Enterococci
resistant S aureus (MRSA), became
S aureus
Klebsiella sp
the predominant causes of hospitalP aeruginosa
S marcescens
Respiratory syncytial virus Influenza
acquired infections in the NICU.
Skin/soft tissue/surgical site CONS
Enterococci
Today, gram-positive cocci conS aureus
S marcescens
tinue to cause the largest proAspergillus sp
portion of infections, and many,
Gastrointestinal tract
Rotavirus
Anaerobic bacteria
including MRSA, CONS, and
Coronavirus
Conjunctivitis/Ocular
CONS
S marcescens
vancomycin-resistant enterococci
P aeruginosa
(VRE), are multidrug-resistant.
Urinary tract
Gram-negative bacilli
Candida sp
Gram-negative bacilli are responsiEnterococci
ble for 20% to 30% of cases of lateEndocarditis
CONS
Candida sp
onset sepsis and 30% of nosocomial
S aureus
Central nervous system
CONS
S marcescens
pneumonias (Table 1). Many gramS aureus
Enterobacter sp
negative pathogens are also
Candida sp
multidrug-resistant, including orOsteoarthritis
S aureus
Gram-negative bacilli
ganisms that express extendedGroup B streptococci
Candida sp
spectrum beta-lactamases such as K
CONS ⫽ coagulase-negative staphylococci, S aureus include methicillin-resistant S aureus, Enterococcal
pneumoniae, K oxytoca, and other
sp include vancomycin-resistant enterococci
enterobacteriaceae such as E coli.
Such enzymes can degrade thirdthe NICU. The burden of infections from these microgeneration cephalosporins, and organisms expressing
organisms in affected infants is enormous. Approxithese beta-lactamases may be treated successfully only
mately 40% of all infections are caused by CONS, and
with carbapenem antibiotics such as imipenem and
nearly 5% of NICU patients develop bacteremia with
meropenem. Candida sp, particularly C albicans and C
CONS. Overall, these pathogens are responsible for 40%
parapsilosis, have become increasingly common and
to 50% of bloodstream infections; 29% of eye, ear, nose,
cause about 10% of late-onset infections. Finally, viral
and throat infections; 19% of skin and soft-tissue infecpathogens also can cause infections in NICU patients,
tions; 16% of pneumonias; and 10% of infections of the
and outbreaks of respiratory syncytial virus (RSV) and
gastrointestinal tract. The precise incidence of CONS
rotavirus infections (in parallel with community outinfections is difficult to determine because it often is
breaks) have been well described. Because every unit has
difficult to distinguish a true infection with CONS from
its own, unique endemic flora, active surveillance for
“culture contamination” if only one blood culture is
nosocomial infections is critical to guide empiric antibiobtained.
otic therapy and implement effective preventive strateCONS also can cause meningitis, ventriculoperitoneal
gies.
shunt infections, and right-sided endocarditis associated
Bacterial Pathogens
with the use of central venous catheters or umbilical
Coagulase-negative Staphylococci
venous catheters. Infections due to CONS are late-onset
Since the late 1970s and early 1980s, CONS, particularly
infections; bloodstream infections occur most commonly
S epidermidis, have been recognized as the most comduring the third week of hospitalization. Fortunately,
mon cause of hospital-acquired infections in infants in
CONS infections generally are more indolent than infece82 NeoReviews Vol.4 No.3 March 2003
infectious diseases nosocomial infections
tions caused by other pathogens, but occasionally CONS
infections can follow a virulent course, particularly in
young, ELBW (⬍1,000 g) infants, and rarely they can
cause death.
The increase in infections due to CONS is presumed
to be due to the improved survival and prolonged hospitalization of ELBW infants and the increasing prevalence of specific risk factors. Risk factors for CONS
infections include use of central venous catheters, intravenous lipids, parenteral nutrition, mechanical ventilation, and increased severity of illness. The pathogenesis
of CONS is related to patterns of colonization; CONS
colonize the skin of preterm infants, contaminate the
outside of central venous catheters or catheter hubs,
track down the catheters, and cause bloodstream infections. Most CONS infections are believed to be endemic,
but there are numerous examples of outbreaks. Strains
may persist in an intensive care unit for years. Molecular
typing by pulsed-field gel electrophoresis and other genetic typing technologies is extremely helpful and can
identify outbreak strains; phenotyping is unreliable because speciation by biochemical profiles is inexact and
CONS usually are multidrug-resistant.
Staphylococcus aureus
S aureus is a common pathogen in the NICU and may be
virulent. S aureus causes bloodstream infections and sepsis, skin/soft-tissue/wound infections, osteoarthritis
(which can be multifocal), and less commonly, central
nervous system infections such as meningitis and ventriculitis. Similarly to CONS, the pathogenesis of S aureus is
related to patterns of colonization. It can colonize the
skin, nares, nasopharynx, gastrointestinal tract, respiratory tract, or eyes.
Approximately 7% to 9% of cases of late-onset sepsis,
17% of pneumonias, and 22% of surgical site infections in
patients in the NICU are caused by S aureus. Risk factors
for methicillin-susceptible S aureus (MSSA) infection/
colonization include prolonged duration of hospitalization and low birthweight.
Most MRSA infections appear to be associated with
outbreaks. Healthcare workers frequently are implicated
in transmission; MRSA colonize the anterior nares and
spread from patient to patient by transient hand carriage.
MRSA can become endemic and may colonize as many as
36% of infants in an NICU. Risk factors for MRSA
acquisition are increased length of hospitalization, antibiotic exposure, and instrumentation (eg, indwelling
catheters). MRSA does not appear to be more virulent
than MSSA, but healthcare costs associated with MRSA
are generally higher.
Enterococci
Enterococci are an occasional cause of infections in the
NICU. Overall, 6% of late-onset sepsis cases, 5% of
pneumonias, and 9% of surgical site infections are caused
by enterococcal species. The Pediatric Prevention Network point-prevalence survey from 1999 reported that
10.3% of bloodstream infections and 16.7% of urinary
tract infections were attributed to enterococci. Risk factors for colonization of the gastrointestinal tract and
subsequent infection include increased length of hospitalization, use of indwelling catheters, and prolonged use
of antibiotics.
Outbreaks of vancomycin-resistant E faecium (VREF)
have been described. Extensive environmental contamination has been noted, and outbreaks have been terminated successfully by improved cleaning, restricted use of
vancomycin, cohorting of infected/colonized infants,
and the use of contact precautions. Among the risk
factors for VREF are prolonged treatment with antimicrobial agents and low birthweight.
Gram-negative Pathogens
PSEUDOMONAS AERUGINOSA
P aeruginosa is a well known cause of sepsis, pneumonia,
conjunctivitis, and endophthalmitis and is associated
with high mortality rates. Potential reservoirs for P
aeruginosa in the NICU include resuscitation equipment, humidifiers, incubators, formulas, breast pumps,
sinks and sink drains, tap water, infants who have prolonged lengths of stay, and the hands of healthcare
workers. Among the risk factors for P aeruginosa infection are feeding intolerance, prolonged need for parenteral hyperalimentation, and prolonged treatment with
antibiotics.
KLEBSIELLA SP
Klebsiella sp, particularly K pneumoniae and K oxytoca,
are well-established pathogens in NICU patients that
cause sepsis, urinary tract infections, and pneumonia.
During the 1970s, the most common cause of outbreaks
in the NICU was Klebsiella sp, and most were
kanamycin-resistant. More recently, extended-spectrum
beta-lactamase-producing (ESBL) Klebsiella sp have
been identified that are resistant to third-generation
cephalosporins. The plasmid containing the ESBL gene
can be transmitted to other Enterobacteriaceae sp in vivo.
ENTEROBACTER SP
Enterobacter sp, such as E cloacae, E agglomerans, and E
sakazakii, are less common causes of hospital-acquired
infections in NICUs. Enterobacter sp are multidrugNeoReviews Vol.4 No.3 March 2003 e83
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resistant pathogens and can cause sepsis and meningitis
in preterm infants. Infections with these pathogens are
associated with high mortality rates. Several outbreaks
have been linked to intrinsically contaminated dextrose
for intravenous infusion and powdered infant formula.
Fungal Pathogens
CANDIDA SP
For more than 2 decades it has been recognized that
preterm infants are at increased risk for infections caused
by Candida sp, particularly C albicans and C parapsilosis.
Other Candida sp, such as C tropicalis, C lusitaniae, and
C glabrata, are less common causes of late-onset sepsis.
Resistance to fluconazole and amphotericin can occur in
Candida sp, and testing for susceptibility should be
considered if there is a poor clinical response. Candida sp
cause candidemia, particularly catheter-related, bloodstream infection, and less commonly, urinary tract infections, endocarditis, osteomyelitis, and meningitis. The
crude mortality rate after infection with Candida sp
ranges from 23% to 50%.
Risk factors for invasive disease caused by fungal
pathogens include prematurity, central venous catheters,
histamine2 blockers, antibiotics, parenteral nutrition, intravenous lipids, intubation, prolonged length of hospitalization, and colonization with Candida sp, particularly in the respiratory or gastrointestinal tracts. (See also
Kicklighter SD. Antifungal agents and fungal prophylaxis
in the neonate. NeoReviews. 2002;3:e249-e255.)
MALASSEZIA SP AND TRICHOSPORON SP
Malassezia sp, particularly M furfur and M pachydermatis, are well described, less common causes of late-onset
infections. The most important risk factor is the use of
intravenous lipids because M furfur has the critical
growth requirement of exogenous fatty acids C12 to C24.
Malassezia sp fungemia generally resolves with central
catheter removal; patients do not appear to require systemic antifungal agents.
the source of nosocomial viral infections. Detection of
viral pathogens requires a high index of suspicion because symptoms of viral illnesses in preterm infants may
be nonspecific (eg, apnea, temperature instability). Appropriate diagnostic studies must be ordered.
Bloodstream and Catheter-related
Bloodstream Infections
Bloodstream infections represent the most common nosocomial infection of patients in the NICU, and many
such infections are catheter-related. ELBW infants exhibit the highest rate of these infections, but bloodstream
infections remain the most common infection, even
among infants whose birthweights are 2,500 g or
greater. Late-onset sepsis is an important determinant of
morbidity and mortality; the length of hospitalization
increases in infants treated for sepsis. The overall risk of
dying of late-onset sepsis is 17%; rates are higher for
gram-negative pathogens such as P aeruginosa (40%) and
fungi (15% to 50%) and lower for CONS (10%). As even
smaller preterm infants survive, the mortality rate due to
respiratory causes among infants whose gestational age is
23 to 27 weeks has decreased, but the mortality rate from
sepsis increased from 14% in 1983 through 1990 to 44%
in 1992 through 1996.
Respiratory Tract Infections
Pneumonia is the second most common nosocomial
infection in patients in the NICU and causes about 15%
of hospital-acquired infections. The rate of ventilatorassociated pneumonia varies by center, with a median of
3.3 episodes of pneumonia per 1,000 ventilator-days.
Although both gram-negative and -positive pathogens
cause pneumonia, mortality from the former is much
higher. Accurate diagnosis of nosocomial pneumonia can
be very difficult in preterm infants because radiographic
changes may be due to atelectasis or noninfectious diseases such as bronchopulmonary dysplasia rather than
infection, and infants rarely undergo invasive diagnostic
procedures such as bronchoscopy.
Viruses
Hospital-acquired viral infections in NICU patients parallel community illnesses. As many as 30% of infections of
the gastrointestinal tract and 5% of eye, ear, nose, and
throat infections are caused by viral illnesses. Outbreaks
caused by respiratory viruses such as RSV and influenza
have been described, as have outbreaks caused by rotavirus. Preterm infants may be asymptomatic and may shed
viruses for prolonged periods, thus contaminating the
environment and facilitating patient-to-patient spread
via the hands of staff. Ill healthcare workers also may be
e84 NeoReviews Vol.4 No.3 March 2003
Strategies for Prevention of Nosocomial
Sepsis
Reducing the incidence of nosocomial sepsis requires a
multifaceted approach. Prevention of preterm birth is
potentially the most effective strategy to decrease the risk
of nosocomial sepsis by reducing the size of the most
susceptible population in the NICU. A review of that
topic is beyond the scope of this paper (see Guinn D,
Gibbs R. Infection-related preterm birth: a review of the
evidence. NeoReviews. 2002;3:e86-e96), but it is worth
infectious diseases nosocomial infections
noting that the rate of prematurity has significantly increased in the United States over the past 20 years.
There are, however, a number of simple care practices
that can reduce the probability of an infant developing a
hospital-acquired infection. These include elimination of
overcrowding and understaffing, careful preparation and
storage of infant formulas, decreasing the number of heel
sticks and attempts at venipuncture, using single-dose
administration of medications such as albumin, avoiding
drugs associated with an increased risk of nosocomial
infection (histamine2 blockers and dexamethasone), sterilization of resuscitation bags and masks, and use of
sterile suctioning techniques. Because many episodes of
bacteremia are associated with indwelling lines or mechanical ventilation, common sense dictates avoiding
their use or minimizing the number of catheter or ventilator days. Ventilator days can be minimized by using
interventions that prevent or lessen the severity of respiratory distress syndrome (eg, antenatal steroids and surfactant), permit rapid weaning (eg, permissive hypercapnia, closure of a patent ductus arteriosus), or use
noninvasive forms of respiratory support such as continuous positive airway pressure.
Care practices that are likely to reduce the incidence of
catheter-related infections include: early institution of
enteral feedings, use of human milk feedings, discontinuation of parenteral alimentation (especially intravenous
lipids) a few days short of full feedings, impeccable
central venous catheter care (sterile insertion techniques
by skilled personnel and dressing changes with careful
disinfection of the insertion site and care of the hub),
limitation of open catheter circuits and heparin flushes,
careful preparation of intravenous fluids and blood products, and routine change of administration sets every
72 hours (or within 24 hours if lipids are used). Recently
suggested novel preventive technologies that have been
examined in adults include use of silver sulfadiazineimpregnated catheters and cuffs, heparin-bonded catheters, and antibiotic-coated (eg, rifampin-minocycline)
and -impregnated catheters. The latest Healthcare Infection Control Practices Advisory Committee (HICPAC)
guidelines (2002) recommend use of chlorhexidine for
cutaneous antisepsis and anti-infective-impregnated
catheters if institutional rates of infection are greater than
3.3 bloodstream infections per 1,000 catheter days despite full adherence to maximal barrier precautions, especially for high-risk patients. Those guidelines have not
been adapted for the neonatal population. Furthermore,
antiseptic- or antibiotic-impregnated catheters are unavailable for the NICU population.
Handwashing/“Degerming”
Handwashing and “degerming” remain the simplest and
most effective methods of preventing transmission of
infectious agents from clinicians to infants and infants to
infants. Six of seven hospital-based studies (including
two in NICUs) demonstrated that improved hand hygiene techniques significantly reduced infection rates.
The fourth edition of the Guidelines for Perinatal Care
recommends the following practices:
●
●
●
Personnel should remove rings, watches, and bracelets
before entering nursery or obstetric areas.
Fingernails should be trimmed short, and no artificial
fingernails or nail polish should be permitted.
A 10-second wash is recommended before and after
handling each infant.
Three types of skin flora colonize the hands of nursery
personnel: resident flora survive and multiply on the skin,
transient flora represent recently acquired “superficial”
contamination and may include pathogens acquired
from one patient and potentially transferable to another,
and infectious flora (eg, S aureus) are capable of causing
localized infections in healthcare workers or infants.
Handwashing with soap and water is the most effective
method of removing soil or proteinaceous material and
also may decrease the number of transient flora (because
they reside on the skin surface). However, handwashing
with soap and water also carries the risk of dispersing
bacterial colonies. Even brief skin-to-skin contact can
transmit several logs of bacteria. Degerming (using an
alcohol-based hand rub with emollient) currently is recommended before and after all patient contacts. It is
effective at reducing the number of bacterial, fungal, and
viral pathogens.
A number of alcohol-containing products are available, but recent data suggest variations in effectiveness.
Skin emollients decrease the dispersal of bacteria, but
may reduce the effectiveness of chlorhexidine-containing
soaps. Soaps and detergents (particularly those that are
anionic and cationic), paper towels, and gloves can damage the skin, and damaged skin harbors more potential
pathogens. In addition, frequent handwashing (even
with soap and water) may affect skin health adversely by
raising the pH. Routine gowning in the nursery has not
been shown to be an effective strategy, but should be
used by healthcare workers coming in contact with infants who are colonized with pathogenic or resistant
microorganisms to avoid contaminating the clothing of
healthcare workers. Gloves have been advocated as a
method of reducing infections, but they may worsen skin
condition and promote bacterial growth. Gloves should
NeoReviews Vol.4 No.3 March 2003 e85
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be worn when caring for infants on droplet or contact
precautions or when touching blood, body fluids, respiratory tract secretions, mucous membranes, or objects
(including equipment) contaminated by these secretions.
Needless to say, compliance with handwashing is
poor. In a recent interventional study to evaluate the
impact of an alcohol-based gel in improving hand hygiene compliance, Harbarth and associates demonstrated
that the use of an alcohol-based gel improved compliance, but even with an active educational program, compliance never exceeded 50%. Doctors and nurses remain
the least compliant groups.
The skin of preterm newborns is thinner, more permeable, and more easily injured with minor trauma compared with term infants. This has led some investigators
to recommend application of topical emollients to the
smallest infants. Two small, randomized trials suggested
that topical emollient therapy might reduce the incidence of bloodstream infections, but the risk of nosocomial infection was not decreased in a recently completed
large, randomized clinical trial of infants weighing 500 to
750 g.
Skin Antisepsis
Skin antisepsis at catheter insertion sites and sites of
venipuncture is essential. Eight randomized, prospective
trials compared 10% povidine-iodine with chlorhexidinecontaining antiseptic for prevention of bloodstream infections involving central venous catheters and arterial
catheters. Seven of the trials found lower rates of catheter
colonization in the chlorhexidine group, and three of five
trials showed a significant reduction in central venous
catheter-related bloodstream infections. Only a single
study (comparing 0.5% chlorhexidine with povidoneiodine) was conducted in a NICU, but the study was not
sufficiently large to assess differences in bloodstream
infection rates. In a recently published randomized trial
in neonates, the use of a chlorhexidine patch reduced
catheter tip colonization, but not bloodstream infections. Infants assigned to the chlorhexidine patch group
had an increased risk of contact dermatitis. At present,
skin antisepsis is not recommended for neonates (Infectious Diseases Society of America, HICPAC guidelines).
Antibiotic Prophylaxis
As noted previously, CONS (most frequently S epidermidis) are the most common pathogens responsible for
nosocomial sepsis in neonates. Two smaller randomized
trials documented a reduction in the number of bloodstream infections when vancomycin (25 mcg/mL) was
e86 NeoReviews Vol.4 No.3 March 2003
added to intravenous solutions. No vancomycin-resistant
bacteria were detected in surveillance cultures, but concern about the development of vancomycin resistance
remains. This is particularly true in an era when VRE are
increasingly prevalent. Furthermore, vancomycin resistance recently has been detected in strains of S aureus.
There also has been interest in the use of antifungal
agents to prevent infections with Candida sp. The use of
topical nystatin has not reduced the incidence of fungal
infections. In a recently published randomized clinical
trial, the use of prophylactic fluconazole resulted in a
reduction in colonization and invasive fungal infections.
Although fluconazole resistance was not detected in this
study, resistance to this agent is well described among
several Candida sp. A multicenter study is being
planned.
Immunoprophylaxis
Reduced transplacental transfer of immunoglobulins and
decreased endogenous synthesis of immunoglobulin G
predispose preterm infants to nosocomial infections.
This physiologic hypogammaglobulinemia provides a rationale for prophylactic administration of intravenous
immune globulin (IVIG). Ohlsson and Lacy from the
Cochrane Neonatal Group recently reported a metaanalysis of 19 randomized trials of prophylactic immune
globulin in very low-birthweight infants. When all studies were combined, there was a significant (3%) reduction
in the incidence of sepsis, but there was no reduction in
mortality. Therefore, the use of IVIG is of marginal
importance and because of cost considerations should
not be used.
The recombinant forms of some hematopoietic cytokines have been cloned and purified and have been under
clinical investigation for their possible role in modulating
the host defense system to prevent neonatal sepsis. Granulocyte colony-stimulating factor (G-CSF) and
granulocyte-macrophage colony-stimulating factor
(GM-CSF) have the ability to increase the number of
circulating neutrophils and to augment the “cidal” activity of neutrophils and macrophages against infectious
organisms. Data for the efficacy of G-CSF are limited.
A small study (n⫽28) demonstrated reduced infection
incidence in babies who had neutropenia born to women
who had pregnancy-induced hypertension. In a large
randomized clinical trial using GM-CSF (n⫽264), Cairo
did not achieve a significant reduction in the incidence of
nosocomial sepsis. However, in a smaller study by Carr
(n⫽75), the incidence of bloodstream infection was reduced from 46% to 31% with prophylactic GM-CSF.
infectious diseases nosocomial infections
Potential Better Practices for Preventing
Nosocomial Infection
Table 2.
Handwashing
●
Meticulous attention to handwashing, with regular monitoring and
surveillance of handwashing practice and reporting of compliance.
Nutrition
●
●
●
●
No alteration of hyperalimentation solutions after preparation.
Initiation of enteral feedings as early as possible.
Reduced exposure to intravenous lipids and hyperalimentation.
Promotion of the use of human milk, ensuring proper collection and storage.
Skin Care
●
●
●
Initiation of a skin care protocol for all neonates weighing <1,000 g, the
goals of which are to promote skin maturation and to prevent skin
breakdown.
Reduced laboratory testing that requires venipuncture or heelstick.
Development of a systematic approach to intravenous therapy that reduces
the frequency and number of skin punctures for placement of an intravenous
catheter.
with 66 NICUs that did not implement the program, the percentage
decrease in nosocomial infection
rates and coagulase-negative staphylococcal
infections
between
1994 and 1996 was greater
(P⫽.058 for all nosocomial infections and P⫽.026 for coagulasenegative staphylococcal infections)
in the study units. The Vermont
Oxford Network now is extending
this quality improvement program
to other hospitals in its database
system.
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domized, double-blind, placeboaerobic culture bottle.
controlled trial of prophylactic recom● Preference for two samples of 1 mL each in two aerobic culture bottles.
binant
human
granulocyte● Development of a method to distinguish true infection from a contaminated
macrophage colony-stimulating factor
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atr. 1999;134:64 –70
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Carr R, Modi N, Dore CJ, El-Rifai R,
● Minimization of the interruption of the ventilator-endotracheal tube circuit.
Lindo D. A randomized, controlled
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in human newborns less than 32 weeks
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NeoReviews Quiz
8. The epidemiology of pathogens responsible for nosocomial sepsis in high-risk neonates has changed over
the years. Of the following, the current organism most likely to cause bloodstream infection among highrisk neonates is:
A.
B.
C.
D.
E.
Candida albicans.
Escherichia coli.
Pseudomonas aeruginosa.
Respiratory syncytial virus.
Staphylococcus epidermidis.
9. The risk factors for hospital-acquired infections among infants in the neonatal intensive care unit vary,
depending on the involved organism. Of the following, the risk factor most associated with infection by
Malassezia furfur is use of:
A.
B.
C.
D.
E.
Antibiotics.
Central venous catheter.
Endotracheal intubation.
Intravenous lipid emulsion.
Histamine2 blockers.
10. Reducing the incidence of nosocomial sepsis requires a multifaceted approach. Of the following, the
strategy confirmed to be most useful in the prevention of nosocomial sepsis among high-risk neonates is
the use of:
A.
B.
C.
D.
E.
Granulocyte colony-stimulating factor.
Handwashing.
Intravenous immunoglobulin.
Skin chlorhexidine antisepsis.
Vancomycin in intravenous solutions.
NeoReviews Vol.4 No.3 March 2003 89