Hospital-Acquired Infections 

Updated: Dec 08, 2016
Author: Haidee T Custodio, MD; Chief Editor: Russell W Steele, MD 

Overview

Practice Essentials

Hospital-acquired infections are caused by viral, bacterial, and fungal pathogens; the most common types are bloodstream infection (BSI), pneumonia (eg, ventilator-associated pneumonia [VAP]), urinary tract infection (UTI), and surgical site infection (SSI).

Risk factors for catheter-associated BSI in neonates include the following[1] :

  • Catheter hub or exit-site colonization

  • Catheter insertion after the first week of life

  • Duration of parenteral nutrition

  • Extremely low birth weight (< 1000 g) at catheter insertion

  • In the pediatric ICU, neutropenia, prolonged catheter dwell time (>7 days), percutaneously placed central venous lines, and frequent manipulation of lines have been identified as risk factors for catheter-associated BSI[2]

Risk factors for candidemia in neonates include the following[3] :

  • Gestational age of less than 32 weeks

  • 5-minute Apgar scores below 5

  • Shock, disseminated intravascular coagulation

  • Prior intralipid use

  • Parenteral nutrition, central venous line placement

  • H2 blocker administration

  • Intubation

  • Hospital stay longer than 7 days

Risk factors for VAP in pediatric patients include the following[4, 5] :

  • Reintubation

  • Genetic syndromes

  • Immunodeficiency, immunosuppression

  • Prior BSI[6]

Risk factors for hospital-acquired UTI in pediatric patients include the following[7] :

  • Bladder catheterization

  • Prior antibiotic therapy

  • Cerebral palsy

The source of infection may be suggested by the instrumentation, as follows:

  • Endotracheal tube: Sinusitis, tracheitis, pneumonia

  • Intravascular catheter: Phlebitis, line infection

  • Foley catheter: UTI

Patients with pneumonia may have the following:

  • Fever, cough, purulent sputum

  • Abnormal chest auscultatory findings (eg, decreased breath sounds, crackles, wheezes)

Patients with UTI may have the following:

  • Fever or normal temperature

  • Tenderness, suprapubic (cystitis) or costovertebral (pyelonephritis)

  • Cloudy, foul-smelling urine

See Clinical Presentation for more detail.

Diagnosis

Because not all bacterial or fungal growth on a culture is pathogenic and because such growth may reflect simple microbial colonization, interpretation of cultures should take into account the following:

  • Clinical presentation of the patient

  • Reason for obtaining the test

  • Process by which the specimen was obtained

  • Presence or absence of other supporting evidence of infection

Methods used to diagnose and characterize BSIs include the following:

  • Suspected catheter-associated BSI: Differential time to positivity of paired blood cultures (simplest)[8] ; quantitative culture of blood obtained from the catheter and peripheral vein; quantitative culture of catheter segment

  • Suspected fungal infection: Fungal cultures, detection of (1,3)-β-D-glucan and galactomannan

  • Possible thrombosis or vegetations: Imaging studies such as echocardiography

  • Immunocompromised patients: Occasional special studies (eg, cultures for Nocardia, atypical mycobacteria, cytomegalovirus [CMV], and CMV antigenemia)

Tests used to identify pneumonia include the following:

  • Acute-phase reactants

  • Oxygen saturation and hemodynamic studies

  • Chest radiography

  • Sputum Gram stain and culture (if necessary, samples can also be obtained through bronchoalveolar lavage or thoracocentesis)

  • Rapid diagnostic tests (eg multiplex PCR capable of identifying multiple pathogens in a specimen)

Urinalysis and urine culture, along with clinical findings, are essential for differentiating between asymptomatic bacteriuria, cystitis, and pyelonephritis. The following factors should be kept in mind in the interpretation of urine cultures:

  • Number of colonies and species isolated

  • Method of sample collection

  • Time from collection to laboratory processing

  • Sex of the patient

  • Previous antibiotic use

Most experts recommend imaging studies in evaluating children with first-time UTI.

See Workup for more detail.

Management

Medical care includes supportive care addressing shock, hypoventilation, and other complications, along with empiric broad-spectrum antimicrobial therapy.

Management of BSI may include the following:

  • Line removal as appropriate[8]

  • Antibiotic therapy covering gram-positive and gram-negative organisms, started empirically and then tailored according to specific susceptibility patterns

  • Antifungal therapy as appropriate

  • Antiviral therapy as appropriate

  • Prevention through use of catheter disinfection caps

Management of pneumonia includes the following:

  • Initial empiric broad-spectrum antibiotic therapy, later streamlined on the basis of identified organisms and susceptibilities, with attention to the risk of multidrug-resistant (MDR) pathogens

  • Antiviral medications against influenza for symptomatic patients and patients with immunodeficiency or chronic lung diseases to limit morbidity and mortality

Management of UTI includes the following:

  • Removal of indwelling catheters if possible

  • Empiric antibiotic and antifungal therapy

Management of SSI includes the following:

  • Surgical debridement

  • Antibiotic therapy

See Treatment and Medication for more detail.

Background

Healthcare-associated infections (HAI) are defined as infections not present and without evidence of incubation at the time of admission to a healthcare setting. As a better reflection of the diverse healthcare settings currently available to patients, the term healthcare-associated infections replaced old ones such as nosocomial, hospital-acquired or hospital-onset infections.[9] Within hours after admission, a patient's flora begins to acquire characteristics of the surrounding bacterial pool. Most infections that become clinically evident after 48 hours of hospitalization are considered hospital-acquired. Infections that occur after the patient is discharged from the hospital can be considered healthcare-associated if the organisms were acquired during the hospital stay.

Hospital-based programs of surveillance, prevention and control of healthcare-associated infections have been in place since the 1950s.[10] The Study on the Efficacy of Nosocomial Infection Control Project (SENIC) from the 1970s showed nosocomial rates could be reduced by 32% if infection surveillance were coupled with appropriate infection control programs.[11] In 2005, the National Healthcare Safety Network (NHSN) was established with the purpose of integrating and succeeding previous surveillance systems at the Centers for Disease Control and Prevention (CDC): National Nosocomial Infections Surveillance (NNIS), Dialysis Surveillance Network (DSN) and National Surveillance System for Healthcare Workers (NaSH).[12]

Continued surveillance, along with sound infection control programs, not only lead to decreased healthcare-associated infections but also better prioritization of resources and efforts to improving medical care.

Healthcare-associated infections are of important wide-ranging concern in the medical field. They can be localized or systemic, can involve any system of the body, be associated with medical devices or blood product transfusions. This article focuses on the 3 major sites of healthcare-associated infections (ie, bloodstream infection, pneumonia, and urinary tract infection) with focus on the pediatric population.

Pathophysiology

Infectious agents causing healthcare-associated infections may come from endogenous or exogenous sources.

Endogenous sources include body sites normally inhabited by microorganisms. Examples include the nasopharynx, GI, or genitourinary tracts. Exogenous sources include those that are not part of the patient. Examples include visitors, medical personnel, equipment and the healthcare environment.

Patient-related risk factors for invasion of colonizing pathogen include severity of illness, underlying immunocompromised state and/or the length of in-patient stay.

Frequency

United States

Healthcare-associated infections are estimated to occur in 5% of all hospitalizations in the United States.[13] In 1999, national point-prevalence surveys in pediatric intensive care units (PICU) and neonatal intensive care units (NICU) showed 11.9% of 512 patients had PICU-acquired infections, whereas 11.4% of 827 patients had NICU-acquired infections.[14, 15]

The incidence of central line-associated BSI and VAP declined significantly between 2007 and 2012 in critically ill pediatric patients, according to a national cohort study of patients admitted to 173 neonatal intensive care units (NICUs) and 64 pediatric intensive care units (PICUs).[16, 17] No change was observed, however, in the rate of catheter-associated UTI. In the NICUs, the rate of central line-associated BSI decreased from 4.9 to 1.5 per 1000 central-line days during the study period; in the PICUs, the rate fell from 4.7 to 1.0 per 1000 central-line days.[17] The rate of VAP decreased from 1.6 to 0.6 per 1000 ventilator days in the NICUs and from 1.9 to 0.7 per 1000 ventilator days in the PICUs.

In 2014, the Centers for Disease Control and Prevention (CDC) released a pair of reports on healthcare-associated infections, with one indicating that significant progress has been made in their prevention.[18, 19]

In the National and State Healthcare-associated Infections Progress Report, the CDC notes a 44% reduction in central line–associated bloodstream infections and a 20% decrease in infections related to 10 surgical procedures, between the years 2008 and 2012. Other decreases were much smaller, with a 4% reduction in hospital-onset methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections and a 2% decrease in hospital-onset Clostridium difficile infections, occurring between 2011 and 2012. Catheter-associated urinary tract infections (UTIs) increased by 3% between 2009 and 2012.

In the second report, a survey of 11,282 patients from 183 acute care hospitals, Magill and colleagues found that 452 patients (4.0%) had at least 1 healthcare-associated infection (504 total infections). Device-associated infections, such as catheter-associated UTIs, were responsible for 25.6% of these. Surgical-site infections and pneumonia each accounted for 21.8%, and gastrointestinal infections accounted for approximately 17.1%. C difficile was the most common pathogen, causing 12.1% of healthcare-associated infections. The researchers estimated that nationwide, 648,000 patients had at least 1 healthcare-associated infection in 2011, with the total number of such infections coming to an estimated 721,800.

International

Both developed and resource-poor countries are faced with the burden of healthcare-associated infections. In a World Health Organization (WHO) cooperative study (55 hospitals in 14 countries from four WHO regions), about 8.7% of hospitalized patients had nosocomial infections.[20]

A 6-year surveillance study from 2002-2007 involving intensive care units (ICUs) in Latin America, Asia, Africa, and Europe, using CDC's NNIS definitions, revealed higher rates of central-line associated blood stream infections (BSI), ventilator associated pneumonias (VAP), and catheter-associated urinary tract infections than those of comparable United States ICUs.[21] The survey also reported higher frequencies of methicillin-resistant Staphylococcus aureus (MRSA), Enterobacter species resistance to ceftriaxone, and Pseudomonas aeruginosa resistance to fluoroquinolones.

A study of bacteremia in African children found distinct differences in the microbiological causes of nosocomial bacteremia compared with community-acquired bacteremia. Nosocomial bacteremia resulted in a higher rate of morbidity and mortality and longer hospital stay. Because it is largely unrecognized in low-income countries, nosocomial infections are likely to become public health priorities as their occurrence increases.[22]

With increasing recognition of burden from healthcare-associated infections, national surveillance systems have been developed in various countries; these have shown that nationwide healthcare-associated infection surveillance systems are effective in reducing healthcare-associated infections.[23]

Mortality/Morbidity

Healthcare-associated infections result in excess length of stay, mortality and healthcare costs. In 2002, an estimated 1.7 million healthcare-associated infections occurred in the United States, resulting in 99,000 deaths.[24] In March 2009, the CDC released a report estimating overall annual direct medical costs of healthcare-associated infections that ranged from $28-45 billion.[25]

A report from the CDC showed that among the intensive care units in the United States, the year 2009 had 25,000 fewer central line-associated bloodstream infections (CLABSI) than in 2001, representing a 58% reduction. Between 2001 and 2009, an estimated 27,000 lives were saved and potential $1.8 billion cumulative excess health-care costs were prevented. Coordinated efforts from state and federal agencies, professional societies, and healthcare personnel in implementing best practices for insertion of central lines were thought to play a role in this achievement.[26]

Sex

Healthcare-associated infections do not have a discernible sex predilection.

Age

Healthcare-associated infections occur in both adult and pediatric patients. Bloodstream infections, followed by pneumonia and urinary tract infections are the most common healthcare-associated infections in children; urinary tract infections are the most common healthcare-associated infections in adults.[27] Among pediatric patients, children younger than 1 year, babies with extremely low birth weight (≤1000 g) and children in either the PICU or NICU have higher rates of healthcare-associated infections.[9, 14, 15, 27]

 

Presentation

History

Healthcare-associated infections are most commonly caused by viral, bacterial, and fungal pathogens. These pathogens should be investigated in all febrile patients who are admitted for a nonfebrile illness or those who develop clinical deterioration unexplained by the initial diagnosis.

Most patients who have healthcare-associated infections caused by bacterial and fungal pathogens have a predisposition to infection caused by invasive supportive measures such as endotracheal intubation and the placement of intravascular lines and urinary catheters. Ninety-one percent of bloodstream infections were in patients with central intravenous lines (CVL), 95% of pneumonia cases were in patients under going mechanical ventilation, and 77% of urinary tract infections were in patients with urinary tract catheters.[27]

Risk factors for the development of catheter-associated bloodstream infections in neonates include catheter hub colonization, exit site colonization, catheter insertion after the first week of life, duration of parenteral nutrition, and extremely low birth weight (< 1000 g) at the time of catheter insertion.[1] In patients in the PICU, risks for catheter-associated bloodstream infections increase with neutropenia, prolonged catheter dwell time (>7 d), use of percutaneously placed CVL (higher than tunneled or implanted devices), and frequent manipulation of lines.[2] Disruption of catheter dressings has also been shown to increase risk for catheter-related infections.[28]

Candida spp are increasingly important pathogens in the NICU. Risk factors for the development of candidemia in neonates include gestational age less than 32 weeks, 5-min Apgar scores of less than 5, shock, disseminated intravascular coagulopathy, prior use of intralipids, parenteral nutrition administration, CVL use, H2 blocker administration, intubation, or length of stay longer than 7 days.[3]

Risk factors for the development of ventilator-associated pneumonia (VAP) in pediatric patients include reintubation, genetic syndromes, immunodeficiency, and immunosuppression.[4, 5] In neonates, a prior episode of bloodstream infection is a risk factor for the development of VAP.[6]

Risk factors for the development of healthcare-associated urinary tract infection in pediatric patients include bladder catheterization, prior antibiotic therapy, and cerebral palsy.[7]

Physical

In addition to the presence of systemic signs and symptoms of infection (eg, fever, tachycardia, tachypnea, skin rash, general malaise), the source of healthcare-associated infections may be suggested by the instrumentation used in various procedures. For example, an endotracheal tube may be associated with sinusitis, tracheitis, and pneumonia; an intravascular catheter may be the source of phlebitis or line infection; and a Foley catheter may be associated with a urinary tract infection.

Patients with pneumonia may have fever, cough, purulent sputum and abnormal chest auscultatory findings such as decreased breath sounds, crackles or wheezes.

Patients with urinary tract infection may present with or without fever. Patients with cystitis can have suprapubic tenderness while those with pyelonephritis can have costovertebral tenderness. Upon inspection, their urine can be cloudy and foul-smelling.

Neonates on the other hand usually do not present with any of the above findings and may have very subtle and nonspecific signs of infection. Fever may or may not be present. Signs of infection can include temperature and/or blood pressure instability, apnea, bradycardia, lethargy, fussiness, and feeding intolerance.

Causes

In a survey done on 110,709 pediatric ICU patients, 6,290 healthcare-associated infections were noted.[27] The top 3 major sites of infections, accounting for 64% of all healthcare-associated infections, were bloodstream infections (28%), pneumonia (21%), and urinary tract infection (15%). Each of these infections was strongly associated with use of an invasive device.

The top 3 pathogens in bloodstream infections were coagulase-negative staphylococci (38%), Enterococcus (11%), and S aureus (9%). Candida albicans accounted for about 5.5% of bloodstream infections. The top 3 pathogens for pneumonia were P aeruginosa (22%), Saureus (17%), and Haemophilus influenzae (10%). The top 3 pathogens for urinary tract infections were Escherichia coli (19%), C albicans (14%), and P aeruginosa (13%). Gram-negative enteric organisms accounted for about 50% of all urinary tract infections. The top 3 pathogens for surgical site infections were S aureus (20%), P aeruginosa (15%), and coagulase-negative staphylococci (14%).

Methicillin-resistant staphylococcus aureus (MRSA) has become a prevalent cause of infections. Traditionally, community-associated MRSA infections have been associated with USA300 or USA400 strains and healthcare-associated infections with USA100 or USA200 strains. However this distinction is becoming less clear with USA300 strains now increasingly identified as a cause of HAI. A population-based study showed MRSA USA300 was not associated with mortality for either central line–associated bloodstream infections or community-onset pneumonia.[29]

Surgical site infections (SSI) occur within 30 days after the operative procedure or within 1 year if an implant was placed. Criteria for the diagnosis of SSI include purulent drainage at the site of incision, clinical symptoms of infection (such as pain, redness, swelling, etc), presence of an abscess, isolation of organism from the site culture, and clinical diagnosis of SSI by the surgeon.[30]

Rotavirus continues to be a cause of acute gastroenteritis in hospitalized children, with greatest susceptibility in children younger than 3 years. Aside from having nonbloody diarrhea, patients may present with fever, vomiting, and abdominal cramps. Other viruses that can cause hospital-associated gastroenteritis include norovirus and adenoviruses. Gastroenteritis due to adenovirus can be especially debilitating in immunocompromised patients.

Clostridium difficile is the most important bacterial cause of healthcare-associated gastroenteritis. Associated clinical conditions include asymptomatic carriage, diarrhea, and pseudomembranous colitis. Diagnosis is suspected in a patient with diarrhea and recent history of antibiotic use (especially cephalosporins and clindamycin).

 

DDx

 

Workup

Laboratory Studies

Laboratory investigations should be guided by the results of a detailed physical examination and review of systems.

Caution should be taken when interpreting laboratory results because not all bacterial or fungal growth on a culture are pathogenic. Growth on cultures may reflect simple microbial colonization. Consider the following:

  • Clinical presentation of the patient

  • Reason for obtaining the test

  • The process by which the specimen was obtained (eg, a urine culture obtained through a newly placed Foley catheter is less likely to be contaminated by microbial colonization)

  • The presence of other supporting evidence of infection (eg, the significance of bacterial growth on tracheal aspirate culture is strengthened by the presence of radiographic changes and clinical signs compatible with pneumonia)

By the same token, known "contaminant" skin organisms such as coagulase-negative staphylococcus, viridans streptococcus, Micrococcus, Corynebacterium, Propionibacterium, and Bacillus species should not easily be dismissed as contaminants if they grew on cultures of normally sterile body fluids (eg, blood, joint fluid, cerebrospinal fluid [CSF]), especially if the patient was at high risk for severe infections (eg, immunocompromised, neonates). Repeating cultures may help establish presence or absence of infection. Fungal growth on a blood culture should never be dismissed as "contamination."

Bloodstream infections

Among the different methods used to establish the catheter as the source of bloodstream infections (catheter-associated bloodstream infection), the differential time to positivity of paired blood cultures is the simplest.[8] The catheter is confirmed as the source of bloodstream infection if the blood culture from the catheter showed microbial growth 2 hours or more earlier than a peripheral blood culture obtained at the same time. The other methods include quantitative cultures of blood obtained from the catheter and peripheral vein and also, quantitative culture of catheter segment. Unfortunately, quantitative culture is not readily available in most laboratories and culture of the catheter requires pulling out the device.

Multiple blood cultures over 24 hours and appropriate volume of blood sample may increase the yield in cases of intermittent or low-inoculum bacteremia. Fungal cultures should be obtained if fungal infection is suspected. The laboratory should incubate cultures longer for fungus detection than for other pathogens.

Imaging studies such as echocardiography should be considered if thrombosis or vegetations is a concern. Candidate patients include those who have prolonged or persistent bacteremia or fungemia despite antimicrobial therapy or in patients with a new-onset murmur.

In immunocompromised patients, special studies are occasionally requested, such as cultures for nocardia and atypical mycobacteria, cytomegalovirus, and cytomegalovirus antigenemia detection.

Pneumonia

Acute phase reactants (peripheral WBC count, erythrocyte sedimentation rate, C-reactive protein) may be elevated but are not specific in distinguishing bacterial from viral pneumonia.

Decreasing oxygen saturation and worsening hemodynamic status are clues to the presence of pneumonia.

The presence of a new infiltrate on chest radiograph is supporting evidence of pneumonia; however, it may sometimes be difficult to differentiate from atelectasis.

Sputum gram stain and cultures may be useful. However, especially in the case of young children unable to effectively cough up phlegm, sputum samples maybe contaminated by saliva and upper respiratory tract organisms. An acceptable sample should have less than 10 squamous epithelial cells, more than 25 neutrophils per low-power field and culture growing a predominant organism.

As in the case of sputum samples, materials obtained via suctioning of endotracheal, nasotracheal, and tracheostomy tubes may not be reliable because these may be contaminated by upper respiratory tract organisms. Other methods to obtain specimens for microbiologic evaluation include bronchoalveolar lavage and thoracentesis.

Efforts to distinguish tracheobronchial colonization, ventilator-associated tracheobronchitis, and ventilator-associated pneumonia may help avoid inappropriate antibiotic use.[31]

Rapid diagnostic tests may be valuable in specific cases. Examples include the direct fluorescent antibody test for Legionella organisms; polymerase chain reaction tests for Bordetella pertussis, Mycoplasma pneumoniae, Chlamydophila pneumoniae; immunofluorescence tests for influenza, respiratory syncytial virus, and Pneumocystis jiroveci; and modified acid-fast stains for mycobacteria.

Urinary tract infection

Urinalysis and urine culture along with clinical findings are essential in differentiating asymptomatic bacteriuria, cystitis and pyelonephritis. The presence of pyuria, bacteria, nitrites and leukocyte esterase on urinalysis makes urinary tract infection likely.

Urinary tract infection is highly likely when the urine culture (obtained by transurethral catheterization) is growing more than 100,000 colony-forming units/mL of a single organism. Urine culture interpretation should be taken with caution as this may lead to overdiagnosis and subsequent unnecessary evaluation and treatment. The following factors should be kept in mind when interpreting urine cultures:

  • Number of colonies and species isolated

  • Method of sample collection

  • Time from collection to laboratory processing

  • Sex of the patient

  • Previous antibiotic use

Although imaging studies are controversial, they are recommended by most experts in evaluating children with first-time urinary tract infection. Renal ultrasonography and voiding cystourethrography are the 2 most commonly used modalities to evaluate for anatomical abnormalities. Renal ultrasonography may also help detect abscesses or phlegmons in patients unresponsive to antibiotic therapy.

Other healthcare-associated infections

Cultures of specimen from the surgical site infection may reveal pathogens and help tailor antibiotic therapy.

Identification of etiologic agents of gastroenteritis was traditionally done with either stool culture or antigen testing. However, the advent of multiplex PCRs able to detect multiple pathogens (bacteria, virus, and even parasites) in a single specimen with short turnaround time are now commercially available and are increasingly used in practice.

Available tests to detect Clostridium difficile include stool culture, enzyme immunoassay for toxin detection, and polymerase chain reaction tests.

Imaging Studies

Special imaging techniques (eg, ultrasonography, CT scan, MRI) may be helpful in evaluating obscure-site infections.

 

Treatment

Medical Care

Symptomatic treatment of shock, hypoventilation, and other complications should be provided, along with administration of empiric broad-spectrum antimicrobial therapy.

Bloodstream infections

Line removal should be considered if the line is no longer needed; if the infection is caused by S aureus, Candida species, or mycobacteria; if the patient is critically ill; if the patient fails to clear bacteremia in 48-72 hours; if symptoms of bloodstream infection persist beyond 48-72 hours; and if noninfectious valvular heart disease, endocarditis, metastatic infection, or septic thrombophlebitis is present.[8]

Antibiotics with coverage against gram-positive and gram-negative organisms, including Pseudomonas, should be empirically started and then tailored according to susceptibility pattern of isolated organisms.

Antifungal therapy (eg, fluconazole, caspofungin, voriconazole, amphotericin B) in some cases are added to empiric antibiotic coverage. Antiviral therapy (eg, ganciclovir, acyclovir) can be used in the treatment of suspected disseminated viral infections.

Duration of therapy depends on several factors, including isolated pathogen, retention of catheter, or presence of complications (endocarditis, sepsis). For most bacterial organisms, the duration of therapy is 10-14 days after blood cultures become negative.

Pneumonia

Initial empiric antibiotic therapy should be broad and later on streamlined based on results of examination and cultures of sputum, endotracheal suction material and bronchial lavage wash. The choice of empiric antibiotic coverage should take into consideration the risk for multidrug-resistant (MDR) pathogens. Risk factors for MDR include antimicrobial therapy over the past 90 days, current hospitalization of 5 days or more, high frequency of antibiotic resistance in the community, or hospital and immunosuppression.[32]

No clear consensus has been reached as to the duration of antimicrobial therapy for ventilator-associated pneumonia (VAP). Many experts treat for 14-21 days. However, shorter course of antibiotic therapy (about 1 wk) may be adequate therapy for some cases.[33]

Antiviral medications against influenza have been used to treat symptomatic patients and patients with immunodeficiency or chronic lung diseases to limit morbidity and mortality.

Urinary tract infection

Indwelling catheters should be removed if possible, to avoid persistence and recurrence of infection. In some cases, removal of catheter may result in spontaneous resolution of bacteriuria or asymptomatic cystitis.

Empiric antibiotic and antifungal therapy should be considered to avoid major complications, including pyelonephritis, renal damage, and bloodstream infections. Duration of therapy is controversial. Most experts recommend at least 10-14 days of therapy for children with sepsis, pyelonephritis, or urinary tract abnormalities.

A study by Mullin et al implemented interventions aimed at reducing catheter-associated urinary tract infection (CAUTI) rates. The intervention included following CDC protocols for positioning, maintenance, and removal of catheters as well as following the American College of Critical Care Medicine (ACCCM) and Infectious Disease Society of America (IDSA) guidelines that recommend that when evaluating fever in the critically ill, urine culture testing should only be indicated for patients who are at high risk for invasive infections. The interventions resulted in a decrease in the CAUTI rate from 3.0 per 1,000 catheter days in 2013 to 1.9 in 2014.[34, 35]

Surgical-site infection

Surgical-site infections (SSIs) should be managed with a combination of surgical care and antibiotic therapy. Antibiotic coverage should be modified once culture results are available.

Severe infections such as streptococcal gangrene and extensive tissue necrosis need aggressive surgical intervention. For these kinds of infections, antibiotics alone may not work.

Other healthcare-associated infections

Rotavirus gastroenteritis is a self-limited disease and only needs supportive care. Medical management should focus on preventing dehydration.

Treatment is not necessary for asymptomatic carriers of Clostridium difficile. For those who have mild symptoms, discontinuance of antibiotics alone may result in resolution of symptoms. For those who have more severe diarrhea, oral metronidazole is the preferred treatment. Oral vancomycin is reserved for treatment failure with metronidazole. Clinical improvement is usually seen within 2 days of initiating therapy, and duration of treatment is usually 10 days.

Surgical Care

Surgical debridement is an integral part of management of surgical-site infections or superinfected decubitus ulcers. Tissue sample should be processed using appropriate stains and cultures to identify the pathogen and its susceptibility.

Consultations

Infectious disease specialists, burn care specialists, and surgical teams are usually involved in the care of complicated cases. Patients with complicated and severe healthcare-associated infections may require expert care from an ICU team.

 

Medication

Medication Summary

Pharmacologic treatment depends on the underlying etiology. Due to increasing antimicrobial resistance patterns, antimicrobial agents should be used judiciously. This includes tapering antimicrobial coverage based on susceptibility tests and clinical response, as well as determining the optimal duration of antibiotic therapy.

 

Follow-up

Deterrence/Prevention

The Healthcare Infection Control Practices Advisory Committee (HICPAC) has developed a guideline for isolation precautions to prevent transmission of infectious agents in healthcare settings.[36, 37]

Standard precautions are to be applied to the care of all patients in all healthcare settings regardless of the suspected or confirmed presence of an infectious agent. This is the primary strategy in preventing transmission of infectious agents among patients and healthcare personnel.

Transmission-based precautions are used in addition to standard precautions when caring for patients who are infected or colonized with pathogens transmitted by airborne, droplet, or contact routes.

Airborne precautions are used to prevent transmission of airborne droplet nuclei–containing microorganisms. These droplet nuclei remain suspended in air. Precautions include use of single-patient rooms, negative air-pressure ventilation, and N95 respirator masks or higher. Organisms transmitted by airborne route include Mycobacterium tuberculosis, rubeola (measles) virus, and the varicella-zoster virus. Droplet precautions are used to prevent transmission of droplets containing microorganisms propelled less than 3 feet by coughing or sneezing by an infected person. Precautions include use of mask in the room and use of single-patient room or, if not feasible, cohorting of patients separated at least 3 feet apart.

Conditions/pathogens for which droplet precautions should be used include adenovirus, diphtheria, H influenzae type b, hemorrhagic fever viruses, influenza, mumps, M pneumoniae, Neisseria meningitidis, parvovirus B19, pertussis, plague (pneumonic), rubella, severe acute respiratory syndrome (SARS), streptococcal pharyngitis, pneumonia, or scarlet fever.

Contact precautions are used to prevent transmission of microorganisms via direct or indirect contact with infected or colonized persons. Precautions include use of single-patient room (if not feasible, cohort patients infected with the same organism), use of gowns and gloves, and hand hygiene after glove removal.

Conditions/pathogens for which contact precautions should be used include multidrug-resistant bacteria (eg, vancomycin-resistant enterococci, methicillin-resistant S aureus [MRSA], multidrug-resistant gram negative bacilli), C difficile, diphtheria, enteroviruses, E coli O157:H7 and other Shiga toxin-producing E coli, hepatitis A virus, herpes simplex virus (neonatal, mucocutaneous, or cutaneous), herpes zoster in a normal host (localized with no evidence of dissemination), impetigo, noncontained abscess, cellulitis or decubitus ulcer, parainfluenza virus, pediculosis, respiratory syncytial virus, rotavirus, scabies, Shigella, S aureus (cutaneous or draining wounds), and viral hemorrhagic fevers (eg, Ebola, Lassa, Marburg).

Prevention of intravascular catheter-associated infections includes avoidance of unnecessary catheter placement, removal of catheter as soon as possible, aseptic technique during catheter insertion, and minimal manipulation of catheter. CDC guidelines address specific strategies in preventing intravascular catheter-associated infections.[38]

Over the years, increasing evidence is showing potential benefit of using antimicrobial-impregnated catheters, antimicrobial-impregnated dressings, and antimicrobial and ethanol locks in at-risk populations to decrease recurrences of catheter-related bloodstream infections.[39, 40] In addition, reduction in lumen contamination, organism density, and catheter-related bloodstream infections has been shown by scrubbing the catheter hub with devices containing isopropyl alcohol.[41, 42, 43]

Prevention of healthcare-associated bacterial pneumonia includes several category IA recommendations, including education of healthcare workers about infection control procedures, thorough cleaning of devices for sterilization or disinfection, changing the breathing circuit only when it is visibly soiled, hand hygiene, and change of soiled gloves.[44]

Prevention of catheter-associated urinary tract infections includes several category I recommendations, including education of personnel in proper techniques of catheter insertion and care, catheterizing only when necessary, emphasizing handwashing, using aseptic technique for catheter insertion, securing catheter properly, maintaining closed sterile drainage, obtaining urine samples aseptically, and maintaining unobstructed urine flow.[45]

CDC highly recommends handwashing with either a nonantimicrobial soap and water or an antimicrobial soap and water when hands are visibly dirty or soiled with blood and other body fluids. If hands are not visibly soiled, alcohol-based hand rub may be used for routine decontamination of hands.[36]

Disinfection of hospital rooms with hydrogen peroxide vapor in addition to standard cleaning reduces environmental contamination and the risk of infection with multidrug-resistant organisms. In a 30-month prospective cohort intervention study in 6 high-risk units in a 994-bed tertiary care hospital, room decontamination with hydrogen peroxide vapor reduced the risk of acquiring any multidrug-resistant organism by 64% and the risk of acquiring vancomycin-resistant enterococci by 80%.[46, 47]

In an open, prospective study, Maziade et al reported a decrease in hospital-acquired infections with the bacterial species C difficile when probiotics were added to standard preventive measures against C difficile infection in patients taking antibiotics. In the final phase of the study, over 25,000 patients on antibiotics received standard preventive care against C difficile along with a daily oral dose of a probiotic formula containing Lactobacillus acidophilus and L casei. Over a 6-year period, the rate of C difficile infections at the hospital performing the study averaged 2.7 cases per 10,000 patient-days, while the rate at similar hospitals averaged 8.5 cases per 10,000 patient-days.[48]

In a retrospective study, rates of hospital-acquired infections caused by multidrug-resistant organisms (MDRO) or C difficile decreased when an ultraviolet environmental disinfection (UVD) system was used after routine discharge cleaning of contact precautions rooms and other high-risk hospital areas. A 20% decrease in hospital-acquired MDRO and C difficile rates was observed during the 22-month period of UVD use as compared with the 30-month pre-UVD period (2.14 vs 2.67 cases per 1000 patient-days).[49, 50]