Has the epidemiology of nosocomial candidemia changed?

OBJECTIVE: To assess changes in the epidemiology of nosocomial candidemia in the post-fluconazole era among hospitalized patients using a case-control study design. DESIGN: Candidemia case-patients were matched 1:1 on diagnosis, age, and length of stay with control-patients. Conditional logistic regression was used to determine predictors and outcomes of candidemia. Treatment regimens and compliance with national practice guidelines were compared among case-patients. SETTING: Barnes-Jewish Hospital, a 1,278-bed, tertiary-care center affiliated with Washington University School of Medicine, St. Louis, Missouri. PARTICIPANTS: Patients admitted from January 1 to December 31, 2000. Case-patients were identified through the hospital microbiological surveillance system and matched with control-patients. RESULTS: Predictors of candidemia included Hickman catheters (odds ratio [OR], 9.53; 95% confidence interval [CI95], 1.34 to 68.01), gastric acid suppressants (OR, 6.38; CI95, 2.33 to 17.43), nasogastric tubes (OR, 3.69; CI95, 1.27 to 10.78), antibiotics (OR, 1.46; CI95, 1.15 to 1.86), and admission to the intensive care unit (OR, 6.40; CI95, 2.12 to 19.31). The crude case-fatality rate was 40%. Seventeen (15%) of the case-patients received the recommended treatment regimen according to recently published practice guidelines. CONCLUSIONS: The epidemiology of candidemia has changed little at our hospital during the past decade and remains a significant cause of mortality. Further studies on the benefits of preventive therapy will be essential to improve the outcome of this infection.     

Effect of nosocomial vancomycin-resistant enterococcal bacteremia on mortality, length of stay, and costs.

OBJECTIVE: To determine the impact of vancomycin-resistant enterococcal bacteremia on patient outcomes and costs by assessing mortality, excess length of stay, and charges attributable to it. DESIGN: A population-based, matched, historical cohort study. SETTING: A 1,025-bed, university-based teaching facility and referral hospital. PATIENTS: Two hundred seventy-seven vancomycin-resistant enterococcal bacteremia case-patients and 277 matched control-patients identified between 1993 and 2000. RESULTS: The crude mortality rate was 50.2% and 19.9% for case-patients and control-patients, respectively, yielding a mortality rate of 30.3% attributable to vancomycin-resistant enterococcal bacteremia. The excess length of hospital stay attributable to vancomycin-resistant enterococcal bacteremia was 17 days, of which 12 days were spent in intensive care units. On average, dollars 77,558 in extra charges was attributable to each vancomycin-resistant enterococcal bacteremia. To adjust for severity of illness, 159 pairs of case-patients and control-patients, who had the same severity of illness (All Patient Refined-Diagnosis Related Group complexity level), were further analyzed. When patients were stratified by severity of illness, the crude mortality rate was 50.3% among case-patients compared with 27.7% among control-patients, accounting for an attributable mortality rate of 22.6%. Attributable excess length of stay and charges were 17 days and dollars 81,208, respectively. CONCLUSION: Vancomycin-resistant enterococcal bacteremia contributes significantly to excess mortality and economic loss, once severity of illness is considered. Efforts to prevent these infections will likely be cost-effective.     

Impact of ventilator-associated pneumonia on resource utilization and patient outcome.

OBJECTIVE: To assess the effect of ventilator-associated pneumonia on resource utilization, morbidity, and mortality. DESIGN: Retrospective matched cohort study based on prospectively collected data. SETTING: Medical intensive care unit of a university teaching hospital. PATIENTS: Case-patients were all patients receiving mechanical ventilation for 48 hours or more who experienced an episode of ventilator-associated pneumonia. Control-patients were matched for number of discharge diagnoses, duration of mechanical support before the onset of pneumonia among case-patients, age, admission diagnosis, gender, and study period. RESULTS: One hundred six cases of ventilator-associated pneumonia were identified in 452 patients receiving mechanical ventilation. The matching procedure selected 97 pairs. Length of stay in the intensive care unit and duration of mechanical ventilation were greater among case-patients by a mean of 7.2 days (P< .001) and 5.1 days (P< .001), respectively. Median costs were $24,727 (interquartile range, $18,348 to $39,703) among case-patients and $17,438 (interquartile range, $12,261 to $24,226) among control-patients (P < .001). The attributable mortality rate was 7.3% (P = .26). The attributable extra hospital stay was 10 days with an extra cost of $15,986 per episode of pneumonia. CONCLUSION: Ventilator-associated pneumonia negatively affects patient outcome and represents a significant burden on intensive care unit and hospital resources.     

Outcomes of nosocomial bloodstream infections in adult neutropenic patients: a prospective cohort and matched case-control study.

OBJECTIVE: To examine the clinical and epidemiologic features, excess length of stay, extra costs, and mortality attributable to bloodstream infection (BSI) in neutropenic patients with hematologic malignancies. DESIGN: Prospective cohort and matched case-control study. PATIENTS: All adult neutropenic patients with hematologic malignancies admitted to Cologne University Hospital between May 1, 1997, and April 30, 1998, were prospectively observed. Case-patients were defined as patients with nosocomial BSI; control-patients were selected among patients without BSI. RESULTS: During the study period, the BSI rate in neutropenic patients was 14.3 per 100 neutropenic episodes. Eighty-four case-patients were included. Matching was successful for 96% of the cohort; 81 matched pairs were studied. The mean total length of stay was significantly longer for patients with BSI than for control-patients (37 vs 29 days; P = .002). Extra costs attributable to the infection averaged 3,200 dollars (U.S.) per patient. The crude mortality rates of case-patients and control-patients were 16% and 4%, respectively (P = .013), with an attributable mortality of 12% (odds ratio, 11). Eighty-seven percent of patients met the criteria for sepsis according to the American College of Chest Physicians/Society of Critical Care Medicine. Severe sepsis or septic shock occurred in 13% of patients and was correlated with mortality (55% vs 10% in patients without severe sepsis or septic shock; P = .01). CONCLUSIONS: Nosocomial BSI in neutropenic patients is significantly associated with an excess length of hospital stay, extra costs, and excess mortality. Severe sepsis and septic shock are closely correlated with an adverse outcome.     

Impact of severity of illness bias and control group misclassification bias in case-control studies of antimicrobial-resistant organisms.

BACKGROUND: Case-control studies often analyze risk factors for antibiotic resistance. Recently published articles have illustrated that randomly selected control-patients may be preferable to those with the susceptible phenotype of the organism. A possible methodologic problem with randomly selected control-patients is potential bias due to control group misclassification. This occurs if some control-patients did not have clinical cultures performed and thus might have been unidentified case-patients. If this bias exists, these studies might be expected to report lower odds ratios (ORs) because control-patients would be more like case-patients. OBJECTIVE: To analyze potential biases that might arise due to control group misclassification and potentially larger selection biases that may be introduced if control-patients are required to have at least one clinical culture. PATIENTS: One hundred twenty case-patients, 770 control-patients in group 1, and 510 control-patients in group 2. METHODS: Two case-control studies. Case-patients had clinical cultures positive for imipenem-resistant Pseudomonas aeruginosa. The first group of control-patients were random. The second group of control-patients were identical to those in group 1 except being required to have at least one clinical culture. RESULTS: Univariate analyses showed higher ORs for case-patients versus control-patients in group 1 (imipenem [OR, 12.5], piperacillin-tazobactam [OR, 3.7], and vancomycin [OR, 4.7]) as compared with case-patients versus control-patients in group 2 (imipenem [OR, 8.0], piperacillin-tazobactam [OR, 2.5], and vancomycin [OR, 3.0]). CONCLUSION: Requiring control-patients to have at least one clinical culture introduces a selection bias likely because it eliminates patients with less severe illness.     

A large outbreak of Clostridium difficile-associated disease with an unexpected proportion of deaths and colectomies at a teaching hospital following increased fluoroquinolone use.

BACKGROUND AND OBJECTIVE: Fluoroquinolones have not been frequently implicated as a cause of Clostridium difficile outbreaks. Nosocomial C. difficile infections increased from 2.7 to 6.8 cases per 1000 discharges (P < .001). During the first 2 years of the outbreak, there were 253 nosocomial C. difficile infections; of these, 26 resulted in colectomy and 18 resulted in death. We conducted an investigation of a large C. difficile outbreak in our hospital to identify risk factors and characterize the outbreak. METHODS: A retrospective case-control study of case-patients with C. difficile infection from January 2000 through April 2001 and control-patients matched by date of hospital admission, type of medical service, and length of stay; an analysis of inpatient antibiotic use; and antibiotic susceptibility testing and molecular subtyping of isolates were performed. RESULTS: On logistic regression analysis, clindamycin (odds ratio [OR], 4.8; 95% confidence interval [CI95], 1.9-12.0), ceftriaxone (OR, 5.4; CI95, 1.8-15.8), and levofloxacin (OR, 2.0; CI95, 1.2-3.3) were independently associated with infection. The etiologic fractions for these three agents were 10.0%, 6.7%, and 30.8%, respectively. Fluoroquinolone use increased before the onset of the outbreak (P < .001); 59% of case-patients and 41% of control-patients had received this antibiotic class. The outbreak was polyclonal, although 52% of isolates belonged to two highly related molecular subtypes. CONCLUSIONS: Exposure to levofloxacin was an independent risk factor for C. difficile-associated diarrhea and appeared to contribute substantially to the outbreak. Restricted use of levofloxacin and the other implicated antibiotics may be required to control the outbreak     

Absence of excess mortality in critically ill patients with nosocomial Escherichia coli bacteremia.

OBJECTIVE: To evaluate excess mortality in critically ill patients with Escherichia coli bacteremia after adjustment for severity of illness. DESIGN: Retrospective (1992-2000), pairwise-matched (1:2), risk-adjusted cohort study. SETTING: Fifty-four-bed ICU in a university hospital including a medical and surgical ICU, a unit for care after cardiac surgery, and a burns unit. PATIENTS: ICU patients with nosocomial E. coli bacteremia (defined as cases; n = 64) and control-patients without nosocomial bloodstream infection (n = 128). METHODS: Case-patients were matched with control-patients on the basis of the Acute Physiology and Chronic Health Evaluation (APACHE) II system: an equal APACHE II score (+/- 2 points) and diagnostic category. In addition, control-patients were required to have an ICU stay at least as long as that of the respective case-patients prior to onset of the bacteremia. RESULTS: The overall rate of appropriate antibiotic therapy in patients with E. coli bacteremia was high (93%) and such therapy was initiated soon after onset of the bacteremia (0.6 +/- 1.0 day). ICU patients with E. coli bacteremia had more acute renal failure. No differences were noted between case-patients and control-patients in incidence of acute respiratory failure, hemodynamic instability, or age. No differences were observed in length of mechanical ventilation or length of ICU stay. In-hospital mortality rates for cases and controls were not different (43.8% and 45.3%, respectively; P = .959). CONCLUSION: After adjustment for disease severity and acute illness and in the presence of adequate antibiotic therapy, no excess mortality was found in ICU patients with E. coli bacteremia.     

Nosocomial methicillin-resistant and methicillin-susceptible Staphylococcus aureus primary bacteremia: at what costs?

OBJECTIVE: To determine the attributable hospital stay and costs for nosocomial methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) primary bloodstream infections (BSIs). DESIGN: Pairwise-matched (1:1) nested case-control study. SETTING: University-based tertiary-care medical center. PATIENTS: Patients admitted between December 1993 and March 1995 were eligible. Cases were defined as patients with a primary nosocomial S. aureus BSI; controls were selected according to a priori matching criteria. MEASUREMENTS: Length of hospital stay and total and variable direct costs of hospitalization. RESULTS: The median hospital stay attributable to primary nosocomial MSSA BSI was 4 days, compared with 12 days for MRSA (P=.023). Attributable median total cost for MSSA primary nosocomial BSIs was $9,661 versus $27,083 for MRSA nosocomial infections (P=.043). CONCLUSION: Nosocomial primary BSI due to S. aureus significantly prolongs the hospital stay. Primary nosocomial BSIs due to MRSA result in an approximate threefold increase in direct cost, compared with those due to MSSA.     

Influence of matching for exposure time on estimates of attributable mortality caused by nosocomial bacteremia in critically ill patients.

OBJECTIVE: To evaluate the influence of matching on exposure time on estimates of attributable mortality of nosocomial bacteremia as assessed by matched cohort studies. DESIGN: Two retrospective, pairwise-matched (1:2) cohort studies. SETTING: A 54-bed intensive care unit (ICU) in a university hospital. PATIENTS: Patients with nosocomial Escherichia coli bacteremia (n = 68) and control-patients without nosocomial bacteremia (n = 136 for each matched cohort study). INTERVENTION: In both matched cohort studies, the same set of bacteremic patients was matched with control-patients using the APACHE II system. In the first study, control-patients were required to have an ICU stay at least as long as the respective bacteremic patient prior to onset of bacteremia (matching on exposure time). In the second study, control-patients were required to have an ICU stay shorter than the stay prior to the development of bacteremia in the respective bacteremic patient (no matching on exposure time). RESULTS: For bacteremic patients, the mean ICU stay before onset of the bacteremia was 9 days (median, 6 days). In the first matched cohort study, hospital mortality was not different between bacteremic patients and control-patients (44.1% vs 43.4%; P = .999). In the second study, mortality of bacteremic patients and control-patients was also not different (44.1% vs 47.8%; P = .657). Mortality rates between control groups were not different (43.4% vs 47.8%; P = .543). CONCLUSION: Matching or not matching on exposure time did not alter the estimate of attributable mortality for ICU patients with E. coli bacteremia.     

Health costs of air pollution: a study of hospitalization costs.

This study of the hospitalization costs of exposure to air pollution in Allegheny County, Pennsylvania was conducted to determine whether persons exposed to air pollution incurred higher hospital utilization rates and additional costs for treatment. A hospitalization data-base comprising 37,818 total admissions for respiratory, suspect circulatory diseases, and comparison circulatory diseases was tested in a cross-section type analysis for relationships between rates of hospitalization, length of stay, and levels of air quality in the neighborhoods of patients' residence. Air quality was identified using data from 49 monitoring stations. Corrections were made for race, age, sex, smoking habits, median income, and occupation. The results show that hospitalization rates, length of stay, and costs of respiratory and suspect circulatory system diseases were significantly greater among populations residing in the more polluted zones of the County. At average costs for hospitalization in this area in 1972, the total increased cost for the 1.6 million persons in the County was estimated at $9.8 million ($9.1 million for increased hospitalization rates and $0.7 million for increased length of stay). The total health costs resulting from air pollution exposure in this area would be much greater when non-hospitalization costs are also included.     

The impact of methicillin resistance in Staphylococcus aureus bacteremia on patient outcomes: mortality, length of stay, and hospital charges.

OBJECTIVE: To evaluate the impact of methicillin resistance in Staphylococcus aureus on mortality, length of hospitalization, and hospital charges. DESIGN: A cohort study of patients admitted to the hospital between July 1, 1997, and June 1, 2000, who had clinically significant S. aureus bloodstream infections. SETTING: A 630-bed, urban, tertiary-care teaching hospital in Boston, Massachusetts. PATIENTS: Three hundred forty-eight patients with S. aureus bacteremia were studied; 96 patients had methicillin-resistant S. aureus (MRSA). Patients with methicillin-susceptible S. aureus (MSSA) and MRSA were similar regarding gender, percentage of nosocomial acquisition, length of hospitalization, ICU admission, and surgery before S. aureus bacteremia. They differed regarding age, comorbidities, and illness severity score. RESULTS: Similar numbers of MRSA and MSSA patients died (22.9% vs 19.8%; P = .53). Both the median length of hospitalization after S. aureus bacteremia for patients who survived and the median hospital charges after S. aureus bacteremia were significantly increased in MRSA patients (7 vs 9 days, P = .045; 19,212 dollars vs 26,424 dollars, P = .008). After multivariable analysis, compared with MSSA bacteremia, MRSA bacteremia remained associated with increased length of hospitalization (1.29 fold; P = .016) and hospital charges (1.36 fold; P = .017). MRSA bacteremia had a median attributable length of stay of 2 days and a median attributable hospital charge of 6916 dollars. CONCLUSION: Methicillin resistance in S. aureus bacteremia is associated with significant increases in length of hospitalization and hospital charges.     

Impact of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species on clinical outcomes and hospital costs: a matched cohort study.

OBJECTIVES: To evaluate the economic and clinical impact of infection with extended-spectrum beta -lactamase (ESBL)-producing Escherichia coli and Klebsiella species (ESBL-EK). DESIGN: A matched-cohort analysis of the cost of illness. SETTING: An 810-bed, urban, community hospital in Hartford, Connecticut. PATIENTS: Twenty-one case patients infected with ESBL-EK at a site other than the urinary tract were matched with 21 control subjects infected with a non-ESBL-producing organism on the basis of pathogen species, age, anatomic site of infection, hospitalization in the intensive care unit (ICU) during the time of infection, date of hospitalization, and initial antibiotics received. RESULTS: Mean infection-related costs per patient were significantly greater for case patients than for control patients ($41,353 vs $24,902; P=.034). Infection-related length of stay was the main driver of cost, which was prolonged for case patients, compared with control patients (21 vs 11 days; mean difference, 9.7 days [95% confidence interval {CI}, 3.2-14.6 days]; P=.006). The additional cost attributed to the presence of an ESBL-EK infection was $16,450 per patient (95% CI, $965-$31,937). Case patients were more likely than control patients to have clinical failure (P=.027), and the rate of treatment success for case patients whose initial treatment involved antibiotics other than carbapenems was lower than that for their matched control patients (39% vs 83%; P=.013). Treatment was successful in patients for whom initial treatment was with a carbapenem, regardless of the ESBL status of the pathogen. CONCLUSION: The cost of non-urinary tract infections caused by ESBL-EK was 1.7 times the cost of non-urinary tract infections caused by non-ESBL producers. Prompt recognition and appropriate antimicrobial selection may minimize this ESBL-related impact on hospital costs.     

Importance of control group selection for evaluating antimicrobial use as a risk factor for methicillin-resistant Staphylococcus aureus bacteremia.

OBJECTIVE: We investigated the importance of control group selection during an evaluation of antimicrobial use as a risk factor for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia at our institution. METHODS: We performed a case-control study. A case was defined as any patient admitted between January 1997 and May 2001 who developed nosocomial MRSA bacteremia. We used two control groups; control group I consisted of patients with nosocomial methicillin-susceptible S. aureus (MSSA) bacteremia and control group II included only patients without bacteremia. We matched control-patients to case-patients using age, gender, time at risk, and hospital ward. Data collected on all patients included demographics, comorbidities, antibiotic use, time at risk, length of stay, severity of illness, and outcome. RESULTS: We evaluated 63 patients (21 in each group). The three groups were well matched regarding age, gender, underlying diseases, and severity of illness. Patients in the MRSA group were more likely to have received a fluoroquinolone and had a higher mean number of days of fluoroquinolone use than did patients in the MSSA group (P = .027 and P = .015, respectively). However, all measures of fluoroquinolone use were similar for case-patients and for control-patients who did not have nosocomial bloodstream infection. CONCLUSIONS: Control group selection is important in evaluating antimicrobial use as a risk factor for MRSA bacteremia. Using control-patients infected with MSSA, rather than uninfected control-patients, may overestimate the association between antimicrobial use and MRSA infection.     

Active surveillance for candidemia, Australia

Population-based surveillance for candidemia in Australia from 2001 to 2004 identified 1,095 cases. Annual overall and hospital-specific incidences were 1.81/100,000 and 0.21/1,000 separations (completed admissions), respectively. Predisposing factors included malignancy (32.1%), indwelling vascular catheters (72.6%), use of antimicrobial agents (77%), and surgery (37.1%). Of 919 episodes, 81.5% were inpatient healthcare associated (IHCA), 11.6% were outpatient healthcare associated (OHCA), and 6.9% were community acquired (CA). Concomitant illnesses and risk factors were similar in IHCA and OHCA candidemia. IHCA candidemia was associated with sepsis at diagnosis (p<0.001), death <30 days after infection (p<0.001), and prolonged hospital admission (p<0.001). Non-Candida albicans species (52.7%) caused 60.5% of cases acquired outside hospitals and 49.9% of IHCA candidemia (p = 0.02). The 30-day death rate was 27.7% in those > or =65 years of age. Adult critical care stay, sepsis syndrome, and corticosteroid therapy were associated with the greatest risk for death. Systematic epidemiologic studies that use standardized definitions for IHCA, OHCA, and CA candidemia are indicated.     

The economic impact of methicillin-resistant Staphylococcus aureus in Canadian hospitals.

OBJECTIVES: To determine the costs associated with the management of hospitalized patients with methicillin-resistant Staphylococcus aureus (MRSA), and to estimate the economic burden associated with MRSA in Canadian hospitals. DESIGN: Patient-specific costs were used to determine the attributable cost of MRSA associated with excess hospitalization and concurrent treatment. Excess hospitalization for infected patients was identified using the Appropriateness Evaluation Protocol, a criterion-based chart review process to determine the need for each day of hospitalization. Concurrent treatment costs were identified through chart review for days in isolation, antimicrobial therapy, and MRSA screening tests. The economic burden to Canadian hospitals was estimated based on 3,167,521 hospital discharges for 1996 and 1997 and an incidence of 4.12 MRSA cases per 1,000 admissions. SETtING: A tertiary-care, university-affiliated teaching hospital in Toronto, Ontario, Canada. PATIENTS: Inpatients with at least one culture yielding MRSA between April 1996 and March 1998. RESULTS: A total of 20 patients with MRSA infections and 79 colonized patients (with 94 admissions) were identified. This represented a rate of 2.9 MRSA cases per 1,000 admissions. The mean number of additional hospital days attributable to MRSA infection was 14, with 11 admissions having at least 1 attributable day. The total attributable cost to treat MRSA infections was $287,200, or $14,360 per patient The cost for isolation and management of colonized patients was $128,095, or $1,363 per admission. Costs for MRSA screening in the hospital were $109,813. Assuming an infection rate of 10% to 20%, we determined the costs associated with MRSA in Canadian hospitals to be $42 million to $59 million annually. CONCLUSIONS: These results indicate that there is a substantial economic burden associated with MRSA in Canadian hospitals. These costs will continue to rise if the incidence of MRSA increases further.     

The impact of surgical-site infections in the 1990s: attributable mortality, excess length of hospitalization, and extra costs.

OBJECTIVE: To determine mortality, morbidity, and costs attributable to surgical-site infections (SSIs) in the 1990s. DESIGN: A matched follow-up study of a cohort of patients with SSI, matched one-to-one with patients without SSI. SETTING: A 415-bed community hospital. STUDY POPULATION: 255 pairs of patients with and without SSI were matched on age, procedure, National Nosocomial Infection Surveillance System risk index, date of surgery, and surgeon. OUTCOME MEASURES: Mortality, excess length of hospitalization, and extra direct costs attributable to SSI; relative risk for intensive care unit (ICU) admission and for readmission to the hospital. RESULTS: Of the 255 pairs, 20 infected patients (7.8%) and 9 uninfected patients (3.5%) died during the postoperative hospitalization (relative risk [RR], 2.2; 95% confidence interval [CI95], 1.1-4.5). Seventy-four infected patients (29%) and 46 uninfected patients (18%) required ICU admission (RR, 1.6; CI95, 1.3-2.0). The median length of hospitalization was 11 days for infected patients and 6 days for uninfected patients. The extra hospital stay attributable to SSI was 6.5 days (CI95, 5-8 days). The median direct costs of hospitalization were $7,531 for infected patients and $3,844 for uninfected patients. The excess direct costs attributable to SSI were $3,089 (CI95, $2,139-$4,163). Among the 229 pairs who survived the initial hospitalization, 94 infected patients (41%) and 17 uninfected patients (7%) required readmission to the hospital within 30 days of discharge (RR, 5.5; CI95, 4.0-7.7). When the second hospitalization was included, the total excess hospitalization and direct costs attributable to SSI were 12 days and $5,038, respectively. CONCLUSIONS: In the 1990s, patients who develop SSI have longer and costlier hospitalizations than patients who do not develop such infections. They are twice as likely to die, 60% more likely to spend time in an ICU, and more than five times more likely to be readmitted to the hospital. Programs that reduce the incidence of SSI can substantially decrease morbidity and mortality and reduce the economic burden for patients and hospitals.     

Surgical-site infection due to Staphylococcus aureus among elderly patients: mortality, duration of hospitalization, and cost.

OBJECTIVES: To examine the impact of surgical-site infection (SSI) due to Staphylococcus aureus on mortality, duration of hospitalization, and hospital charges among elderly surgical patients and the impact of older age on these outcomes by comparing older and younger patients with S. aureus SSI. DESIGN: A nested cohort study. SETTING: A 750-bed, tertiary-care hospital and a 350-bed community hospital. PATIENTS: Ninety-six elderly patients (70 years and older) with S. aureus SSI were compared with 2 reference groups: 59 uninfected elderly patients and 131 younger patients with S. aureus SSI. RESULTS: Compared with uninfected elderly patients, elderly patients with S. aureus SSI were at risk for increased mortality (odds ratio [OR], 5.4; 95% confidence interval [CI95], 1.5-20.1), postoperative hospital-days (2.5-fold increase; CI95, 2.0-3.1), and hospital charges (2.0-fold increase; CI95, 1.7-2.4; dollar 41,117 mean attributable charges per SSI). Compared with younger patients with S. aureus SSI, elderly patients had increased mortality (adjusted OR, 2.9; CI95, 1.1-7.6), hospital-days (9 vs 13 days; P = .001), and median hospital charges (dollar 45,767 vs dollar 85,648; P < .001). CONCLUSIONS: Among elderly surgical patients, S. aureus SSI was independently associated with increased mortality, hospital-days, and cost. In addition, being at least 70 years old was a predictor of death in patients with S. aureus SSI.     

Hospital costs for patients with lower extremity cellulitis: a retrospective population-based study

Objectives: Hospital admissions for non-purulent lower extremity cellulitis (NLEC) are common and can be prolonged and costly. Newer treatment options and preventive strategies are expected to result in cost savings before implementation, but few studies have quantified the cost of conventional treatment.

Methods: Using the Rochester Epidemiology Project, the incidence of NLEC in Olmsted County, MN in 2013 was 176.6 per 100,000 persons. The subset of patients who required hospitalization for NLEC in 2013 was determined. Hospital admissions were analyzed retrospectively using standardized cost analysis within several relevant categories.

Results: Thirty-four patients had an average hospital length of stay of 4.7 days. The median total inpatient cost was $7,341. The median cost per day was $2,087, with 49% due to room and board. Antibiotics administered for treatment of NLEC contributed a median cost of $75 per day of hospitalization, and laboratory and imaging test costs were $73 and $44, respectively, per day of hospitalization.

Conclusion: Hospitalizations for NLEC can be costly and prolonged with room and board accounting for much of the cost. Therefore, newer management strategies should seek to reduce hospital length of stay and/or avoid inpatient admission to reduce cost.     

Hospital charges for colorectal cancer patients first admitted through an emergency department

Some 11,023 colorectal cancer patients diagnosed in 1992-96 in Connecticut first were admitted to a hospital through a hospital emergency department. The average hospital inpatient charges and average length of stay were about 60 percent higher for emergency department versus nonemergency department first admissions. Emergency department status was an important predictor of charges independent of age at diagnosis and length of stay. Applying these data to the approximately 131,000 colorectal cancers diagnosed in 1998 in the U.S., estimated excess hospital costs due to emergency department versus nonemergency department first admissions for colorectal cancer were about $328 million.     

Quinolone use as a risk factor for nosocomial Clostridium difficile-associated diarrhea.

OBJECTIVE: To determine modifiable risk factors for nosocomial Clostridium difficile-associated diarrhea (CDAD). DESIGN: Case-control study. SETTING: 300-bed tertiary-care hospital. PARTICIPANTS: Hospital inpatients present during the 3-month study period. METHODS: Case-patients identified with nosocomial CDAD over the study period were compared to two sets of control patients: inpatients matched by age, gender, and date of admission; and inpatients matched by duration of hospital stay. Variables including demographic data, comorbid illnesses, antibiotic exposure, and use of gastrointestinal medications were assessed for case- and control-patients. Conditional logistic regression was performed to identify risk factors for nosocomial CDAD. RESULTS: 27 case-patients were identified and were compared to the two sets of controls (1:1 match for each comparison set). For the first set of controls, use of ciprofloxacin (odds ratio [OR], 5.5; 95% confidence interval [CI 95], 1.2-24.8; P=.03) was the only variable that remained significant in the multivariable model. For the second set of controls, prior exposure to cephalosporins (OR, 6.7; CI 95, 1.3-33.7; P=.02) and to ciprofloxacin (OR, 9.5; CI 95, 1.01-88.4; P=.05) were kept in the final model. CONCLUSIONS: Along with cephalosporins, prior quinolone use predisposed hospitalized patients to nosocomial CDAD. Quinolones should be used judiciously in acute-care hospitals, particularly in those where CDAD is endemic.