Adult patients with occult bacteremia discharged from the emergency department: epidemiological and clinical characteristics

Safety of early oral ambulatory treatment of adult patients with bloodstream infections discharged from the emergency department

This study evaluates the safety of early oral ambulatory treatment of adult patients diagnosed with bacteremia after their discharge from the emergency department. A cohort of 206 febrile ambulatory patients was assessed. Bacteremic low-risk patients were recommended an oral treatment and were compared with matched febrile non-bacteremic outpatients. Rates of 14-day mortality and unplanned re-consultations were similar and below 5% in both cohorts, highlighting the safety of oral therapy of low-risk bacteremia, even from its onset.

A simplified scoring model for predicting bacteremia in the unscheduled emergency department revisits: The SADFUL score

BACKGROUND

Bacteremia is a severe complication of infectious disease. Patients with a high bacteremia risk in the emergency department (ED) but misidentified would lead to the unscheduled revisits. This study aimed to develop a simplified scoring model to predict bacteremia in patients with unscheduled ED revisits.

METHODS

Adult patients with unscheduled ED revisits within 72 h with a final diagnosis of infectious disease were retrospectively included. The development cohort included patients visiting the ED from January 1, 2019 to December 31, 2021. Internal validation was performed in patients visiting the ED from January 1, 2022 to March 31, 2022. Variables including demographics, pre-comorbidities, triage levels, vital signs, chief complaints, and laboratory data in the index visit were analyzed. Bacteremia was the primary outcome determined by blood culture in either index visits or revisits.

RESULTS

The SADFUL score for predicting bacteremia comprised the following predictors: "S"egmented neutrophil percentage (+3 points), "A"ge > 55 years (+1 point), "D"iabetes mellitus (+1 point), "F"ever (+2 points), "U"pper respiratory tract symptoms (-2 points), and "L"eukopenia (2 points). The area under receiver operating characteristic curve with 95% confidence interval in the development (1802 patients, 190 [11%] with bacteremia) and the validation cohort (134 patients, 17 [13%] with bacteremia) were 0.78 (0.74-0.81) and 0.79 (0.71-0.88), respectively.

CONCLUSIONS

The SADFUL score is a simplified useful tool for predicting bacteremia in patients with unscheduled ED revisits. The scoring model could help ED physicians decrease misidentification of patients at a high risk for bacteremia and potential complications.

Epidemiology and Factors Associated With Discharging Patients After Blood Culture Collection in the Emergency Department: A Case-Control Study in Japan

Background

Some patients receive the diagnosis of bloodstream infection (BSI) after discharge from the emergency room (ER). Because the safety of discharging patients after a blood culture collection is unknown, the present study aimed to investigate the prevalence, outcomes, and factors associated with BSI diagnosed after ER discharge.

Methods

This monocentric, case-control study compared patients who received a BSI diagnosis after ER discharge with those who were admitted for BSI. Factors associated with ER discharge after a blood culture collection were identified using multivariate logistic regression analysis.

Results

Between January 2014 and December 2020, 5.5% (142/2575) of patients with BSI visiting the ER were initially discharged. This occurred more commonly during the coronavirus disease 2019 (COVID-19) pandemic in 2020. On multivariate analysis, factors independently associated with the discharge of patients with BSI were the absence of hypotension (adjusted odds ratio [aOR], 15.71 [95% confidence interval {CI}, 3.45–71.63]), absence of altered mental status in the ER (aOR, 8.99 [95% CI, 3.49–23.14]), unknown origin at ER discharge (aOR, 4.60 [95% CI, 2.43–8.72]), and low C-reactive protein (aOR, 3.60 [95% CI, 2.19–5.93]). No difference in 28-day mortality was observed between the groups.

Conclusions

BSI is occasionally diagnosed after ER discharge. The prevalence of BSI diagnosed after ER discharge may have increased during the COVID-19 pandemic. Normal vital signs, unknown origin at ER discharge, and low C-reactive protein were important considerations leading to the discharge of these patients.

Non-typhoidal Salmonella bacteremia: comparison of adults and children in a single medical center

Introduction. Non-typhoidal Salmonella (NTS) bacteremia can cause significant morbidity and mortality. There is high incidence of Salmonellosis in the Middle East, including Israel, but there is a paucity of data on the clinical and epidemiological features of children in comparison to adults.Hypothesis/Gap Statement. Previous studies describing the differences between paediatric and adult populations with Salmonella bacteremia are sparse.Aim. This study's aim was to describe the differences between adults and children with NTS bacteremia.Methodology. All records of patients with NTS bacteremia between 1 January 1998 and 31 July 2020 were reviewed. Data regarding clinical manifestations and laboratory results were extracted from the medical records; records of children (aged <18 years) were compared with those of adults.Results. Records for 137 cases of Salmonella bacteremia (69 adults and 68 children, aged 2 days to 98 years) were reviewed. Seventy nine (58 %) patients had concomitant gastrointestinal symptoms. Fifty-eight (84 %) adults and 13 (19 %) children had underlying conditions (P<0.001). Eighteen patients died, none of whom was a child. Over the study period, most of the children (n=46, 67 %) but only five adults were discharged from the emergency department on their first visit to the ED.Conclusions. The main characteristics of NTS bacteremia in children compared to adults, are higher rates of prior discharge from emergency department, higher rate of gastrointestinal symptoms and better prognosis.

Epidemiology and outcome of occult bacteremia in patients discharged from emergency departments or ambulatory units: one-year study

Microbiological diagnosis of bloodstream infection (BSI) is made several hours after blood culture sampling. This delay could be critical in ambulatory clinics, emergency departments, and hospital day care units, as the patient may be discharged prior to blood culture positivity. Our aim was to evaluate the clinical outcome (including the number of readmissions) of patients diagnosed with BSI after discharge. We prospectively included all adult patients with positive blood culture for BSI that was confirmed after discharge from our center (Grenoble-Alpes University Hospital) in 2016. Patients were contacted about their blood culture results, and their clinical status was controlled via an external consultation or their family physician, with hospital readmission if necessary. Clinical outcome, accuracy of initial diagnosis, microbiological epidemiology, and antibiotic prescription were assessed. In 2016, 1433 episodes of positive blood culture were detected in our hospital, with 50 (3.5%) occurring after patient discharge. Clinically relevant bacteria were determined in 32/50 cases (64%), while other positive blood culture results were considered to be contaminants. Clinical reevaluation was performed in 45 patients (90%). The diagnosis was changed during the clinical reassessment of 24/49 patients (49%). Antibiotics were prescribed prior to discharge for 24/50 patients (48%), modified during follow-up for 15/45 (33%), and initiated for 13/45 (29%) at the reevaluation. Overall, 24/45 (53%) patients were readmitted to hospital units after reevaluation. The clinical follow-up of patients with positive blood culture after discharge led to diagnostic changes and hospital readmission in around half of patients.

Blood cultures of adult patients discharged from the emergency department-is the safety net reliable?

We investigated the clinical implications of the practice in our emergency department (ED) of discharging patients with pending blood cultures. We reviewed the medical records of adults discharged with positive blood cultures from the ED of a 330-bed university hospital during a five-year period. Clinical characteristics, laboratory data, and antibiotic treatment prescribed in the ED and at discharge were accessed. Antimicrobial susceptibility profiles were used to determine whether antibiotic treatment was adequate. The outcomes assessed for 90 days following discharge were return to the ED, hospitalization, modified diagnosis, and death. Of 220,681 visits to the ED, 1362 showed positive blood cultures; of these, 307 (22.5%) were from discharged patients. More than half the isolates (56.3%) were considered contaminants. Of 124 visits with true bacteremia, Enterobacteriaceae were the most common pathogens (67.0%). This is concordant with urinary tract infection (UTI) being the most common diagnosis (52.4%). With antibiotic treatment, 69.4% had been discharged with antibiotic treatment, which was adequate in two-thirds of them. Among the 77 who returned to the ED, 27.5% had persistent bacteremia. The diagnosis was changed in 44.2% of them, mostly with brucellosis or bone and joint infections, and 84.4% were subsequently hospitalized. Within three months, 5.6% of bacteremic patients died, all after hospitalization. Bacteremia in discharged patients occurred mainly in association with UTI. Outcomes were generally favorable, although only about half received appropriate antibiotic treatment. Diagnoses were changed in a relatively high proportion of patients following culture results.

Diagnostic performance of initial serum lactate for predicting bacteremia in female patients with acute pyelonephritis

OBJECTIVES

The purpose of the present study was to investigate the diagnostic value of lactate for predicting bacteremia in female patients with acute pyelonephritis (APN).

METHODS

We conducted a retrospective study of female patients with APN who visited the study hospital emergency department. The demographics, comorbidities, physiologies, and laboratory variables including white blood cell count and segmented neutrophil count, C-reactive protein, and initial serum lactate levels were collected and analyzed to identify associations with the presence of bacteremia.

RESULTS

During the study period, a total of 314 patients were enrolled. One hundred twenty-three patients (39.2%) had bacteremia. Escherichia coli was the most frequent pathogen. Logistic regression analysis demonstrated that the lactate level was independently associated with the presence of bacteremia (odds ratio, 1.39 [95% confidence interval, 1.08-1.78]). The C-statistic of the lactate level was 0.67 (95% CI, 0.60-0.73). At a cutoff value of 1.4mmol/L, the lactate level predicted bacteremia with a sensitivity (53.7%), specificity (72.3%), positive predictive value (55.5%), negative predictive value (70.8%), positive likelihood ratio (1.93), and negative likelihood ratio (0.64).

CONCLUSION

The initial serum lactate level showed poor discriminative performance for predicting bacteremia in female patients with APN.

A cross-sectional study of blood cultures and antibiotic use in patients admitted from the Emergency Department: missed opportunities for antimicrobial stewardship

Background

Early review of antimicrobial prescribing decisions within 48 h is recommended to reduce the overall use of unnecessary antibiotics, and in particular the use of broad-spectrum antibiotics. When parenteral antibiotics are used, blood culture results provide valuable information to help decide whether to continue, alter or stop antibiotics at 48 h. The objective of this study was to investigate the frequency of parenteral antibiotic use, broad spectrum antibiotic use and use of blood cultures when parenteral antibiotics are initiated in patients admitted via the Emergency Department.

Methods

We used electronic health records from patients admitted from the Emergency Department at University Hospital Birmingham in 2014.

Results

Six percent (4562/72939) of patients attending the Emergency department and one-fifth (4357/19034) of those patients admitted to hospital were prescribed a parenteral antimicrobial. More than half of parenteral antibiotics used were either co-amoxiclav or piperacillin-tazobactam. Blood cultures were obtained in less than one-third of patients who were treated with a parenteral antibiotic.

Conclusions

Parenteral antibiotics are frequently used in those admitted from the Emergency Department; they are usually broad spectrum and are usually initiated without first obtaining cultures. Blood cultures may have limited value to support prescribing review as part of antimicrobial stewardship initiatives.

Procalcitonin-based indication of bacterial infection identifies high risk acute heart failure patients

BACKGROUND

Bacterial infections in patients hospitalized with acute heart failure are related to worse prognosis, but they can be difficult to diagnose. In this study we evaluated the prevalence, clinical correlates and association with outcomes of significantly elevated procalcitonin levels in patients hospitalized for acute heart failure without clear signs of bacterial infection.

METHODS

1781 patients from the PROTECT trial were included. Patients with a body temperature >38°C, sepsis or active infection requiring IV antibiotics were excluded. Significant elevation of procalcitonin was considered present when levels exceeded 0.20 ng/mL. In-hospital and post-discharge outcomes were compared between groups of patients with and without elevated procalcitonin levels.

RESULTS

Procalcitonin ≥ 0.20 ng/mL was seen in 6.0% of patients (N=104). This group of patients had lower serum albumin, lower hemoglobin, higher leukocyte count, higher C-reactive protein, higher blood urea nitrogen, higher heart rate and more pulmonary rales. Interestingly, no significant differences were observed between the two groups in terms of severity of heart failure evidenced by left ventricular ejection fraction (LVEF) or B-type natriuretic peptide (BNP) levels. Patients with significantly elevated procalcitonin levels were more often classified as treatment failure or unchanged status, and had an increased risk of 30-day all-cause mortality even after adjustment for established prognosticators; HR=2.3 (95% CI, 1.3-4.2), (P=0.005).

CONCLUSION

Patients with acute heart failure and significantly elevated procalcitonin levels, indicating probable undiagnosed/untreated bacterial infection, had poorer in-hospital and post-discharge outcomes, despite similar severity of heart failure.

Occult Klebsiella pneumoniae bacteremia at emergency department: A single center experience

BACKGROUND/PURPOSE

Patients with undetected bacteremia when discharged from a hospital are considered to have occult bacteremia. Klebsiella pneumoniae bacteremia (KPB) is endemic to Taiwan. Our purpose was to study the impact of occult KPB.

METHODS

We retrospectively reviewed the records of patients who were discharged from our emergency department (ED) and subsequently diagnosed with KPB (occult bacteremia), from January 2008 to March 2014. All patients are followed for at least 3 months after the index ED visit. The study group was compared to KPB patients who were directly hospitalized (DH) from ED in 2008. Thirty-day mortality was the primary endpoint.

RESULTS

A total of 913 patients were admitted to our ED with KPB, and 88 of these patients (9.6%) had occult KPB. Among them, 43 had second ED visit and 41 were admitted. The overall 30-day mortality was 2.3%. Relative to patients with occult KPB, DH patients had more respiratory tract infections (p < 0.001) but fewer other intra-abdominal infections (p = 0.015). Liver abscess was the major diagnosis for the second ED visit (37.2%). DH patients had significantly greater 30-day mortality than that of overall patients with KPB (19.2% vs.2.3%, p < 0.001).

CONCLUSION

Most patients with occult KPB had favorable outcomes, but about half of them required a second ED visit. Clinicians should aggressively follow patients with occult KPB and should seek to identify the focus of infection in this endemic area.

[Results of an early intervention program for patients with bacteremia discharged from the Emergency Department]

BACKGROUND AND OBJECTIVE

Occult bacteremia represents 3% of blood cultures drawn in the Emergency Department. In most cases, the evolution is unknown. The aim of the study is to analyze the results obtained after implementation of an intervention program for these patients.

PATIENTS AND METHODS

We describe the results of an early intervention program for patients with bacteremia in the Emergency Department discharged at home, which was implemented in daily clinical activity in Costa del Sol Hospital in Marbella (Malaga). We analyze the epidemiological, microbiological, Charlson comorbidity index, Pitt bacteremia index and 30-day mortality.

RESULTS

During 15 months, 90 patients were located. The median age was 67 years. There was a predominance of males with 54 of cases (60%). The acquisition place was predominantly the community with 51 cases (56.6%), being the most frequent microorganism Escherichia coli with 31 cases (34.4%). The median Charlson index and the bacteremia Pitt index were 1. Thirty-eight of the cases required hospitalization (42.2%). Pitt bacteremia index>1 and exchange antibiotic treatment were the related variables with need for admission. One patient died (1.2%) and 6 patients could not be located (6.6%).

CONCLUSIONS

The implementation of programs of early identification and management of patients with bacteremia in Emergency Department discharged al home allows early recovery of patients who require hospital admission and antibiotic treatment optimization. In our series, mortality after early intervention was low (1.2%).

Isolated pathogens and clinical outcomes of adult bacteremia in the emergency department: a retrospective study in a tertiary Referral Center

BACKGROUND

Approximately two-thirds of the patients with severe sepsis or septic shock are first encountered in the emergency departments (EDs) of western countries, in which bacteremia is present in about 50% of patients with severe sepsis. The situation of bacteremia presenting to the EDs in Taiwan is not well documented. The objective of this study was to examine the epidemiology and microbiology of bacteremia in adult patients who visited the ED of a medical center in southern Taiwan.

METHODS

A retrospective observational study of the epidemiology and microbiology of bacteremia was conducted in the ED of a medical center involving 6,137 adult patients and 13,903 blood cultures.

RESULTS

A total of 831 consecutive patients with 890 episodes of bacteremia were obtained from January 1 to December 31, 2004, indicating a positive culture rate of 13.5% (1,872/13,903). Among these episodes, 525 (59%) were defined as true community-acquired infections followed by 263 (29.5%) as health care-associated infections and 102 (11.5%) as nosocomial infections. Of the 972 isolates, 289 (29.7%) were gram-positive species and 683 (70.3%) were gram-negative species. Urinary tract infections (32.2%, 287/890) were most common in these patients, with Escherichia coli (30.8%, 299/972) being the most common pathogen. Bacteremia caused by Staphylococcus aureus was more common in nosocomial than true community-acquired infections (31.3% vs. 12%) and had significantly higher possibility of resistance to methicillin in infections not purely acquired from community (odds ratio = 24.92; 95% confidence interval, 9.88-62.87). The overall crude mortality rate was 21% and nearly half of the mortalities occurred within 3 days of visiting the ED. All patients discharged inadvertently were uneventful (n = 65, two lost at follow-up).

CONCLUSIONS

Categories of bacteremia acquisition was associated with different distribution of pathogens, antimicrobial resistance, and clinical outcome. Traditional classification might overestimate the problem of drug resistance in community-acquired infections. The concept of health care-associated infection should be introduced to avoid overemphasis of drug-resistant problem in true community-acquired infection.

Characteristics and outcomes of polymicrobial bloodstream infections in the emergency department: A matched case-control study

OBJECTIVES

Polymicrobial bloodstream infection (BSI) is a critical condition and has been increasingly reported; however, the authors were unable to find an emergency department (ED) patient-based study in the literature.

METHODS

A retrospective matched case-control study with a ratio of 1:3 among patients with polymicrobial BSIs in an ED was conducted. The case group was patients aged > 16 years with polymicrobial BSIs. Patients matched for age and sex with monomicrobial BSIs were sampled as the control group. Demographic information, underlying conditions, microbiologic data, and outcomes were collected for further analysis.

RESULTS

From January 2005 to December 2007, a total of 112 episodes of polymicrobial BSIs among 109 patients were included. Two pathogens were isolated among 87 (77.7%) episodes and three were found among 25 (22.3%) episodes. A history of hospitalization within 90 days was an independent risk factor for polymicrobial BSIs (p = 0.003). Intraabdominal infection (p < 0.001) and respiratory tract infection (p = 0.017) were more likely to be associated with polymicrobial BSIs. Gram-negative and Gram-positive bacteria were documented in 95.5 and 46.4% episodes of polymicrobial BSIs, respectively. Inappropriate antimicrobial treatment was observed in 53.6% of polymicrobial BSIs, but only accounted for 23.8% of monomicrobial BSIs (p < 0.001). The overall 30-day mortality rate of the polymicrobial group was significantly higher than those with monomicrobial BSIs (30.3 and 11.6%, respectively; p < 0.001).

CONCLUSIONS

Patients with polymicrobial BSIs had a high mortality rate. Acknowledgment of the clinical and microbiologic characteristics and recognition of patients at risk for polymicrobial BSIs are critical in EDs.

Bacterial pathogens in ambulances: results of unannounced sample collection

The concern that the health care environment may harbor a substantial reservoir of infectious agents has been vigorously examined by microbiology and infectious disease experts. Although universal precautions and disposable equipment reduces risks to patients and providers, the ambulance remains vulnerable to bacterial contamination from biological secretions. Additionally, the nature of emergency medical services creates pressures on prehospital care providers.

OBJECTIVE

We hypothesized that a discrepancy exists between the expectation of disinfection of reusable equipment in emergency medical services (EMS) and the cleaning that actually occurs.

METHODS

We chose five areas within the ambulance for specimen collection for their reasoned propensity to yield a large spectrum of bacteria. Four first-due ambulances were selected for culturing. The crews did not have advance knowledge of the study or sample collection. Specific identifications with antibiotic susceptibility were completed, identifying three multidrug resistant organisms.

RESULTS

Specimens from all four ambulances grew moderate-to-large quantities of environmental and skin flora. Newer, automated microbiological techniques and concerns regarding multiple-drug-resistant organism prevalence as well as the potential for biological warfare make complete identification more important.

CONCLUSIONS

This study examined the bacterial pathogens found in EMS vehicles. Four of the seven species isolated were substantial nosocomial pathogens, and three of these four possess formidable antibiotic resistance patterns. All of the organisms detected are susceptible to the disinfectant agents currently in common use by EMS agencies.

Diagnostic use of C-reactive protein in bacteraemic emergency department patients

OBJECTIVE

To assess C-reactive protein (CRP) as a marker of bacteraemia in ED patients.

METHODS

A retrospective review of a convenience sample of adult patients was conducted at an urban, tertiary care, academic ED. Patients were included in the present study if they had CRP and blood cultures taken during their ED assessment. Neutropenic patients were excluded. Sensitivity, specificity, predictive values and likelihood ratios for CRP in the detection of bacteraemia were calculated.

RESULTS

Over a 12 month period 1214 patients were included in the present study. Blood cultures were positive in 77 (6.3%, 95% confidence interval [CI] 5.0-7.6%), and contaminated in 33 (2.7%, 95% CI 1.8-3.6%). An elevated CRP was 94% sensitive (95% CI 86-98%) and 18% specific (95% CI 16-20%) for concurrent bacteraemia. The positive likelihood ratio for bacteraemia with an elevated CRP was 1.15 (95% CI 1.07-1.23), and the negative likelihood ratio was 0.33 (95% CI 0.23-0.49).

CONCLUSION

Although the present study has limitations, it appears to show that CRP has limited diagnostic utility for the detection of bacteraemia in ED patients.

Non-Typhi Salmonella gastroenteritis in children presenting to the emergency department: characteristics of patients with associated bacteraemia

The records of children with Salmonella gastroenteritis only (n = 97), and those with associated bacteraemia (n = 64), seen in one medical centre during a 12-year period, were analysed retrospectively. Mean patient age was 2.24 +/- 2.8 years (range, 0.05-16 years), and 49% were male. Children with bacteraemia presented after a longer duration of symptoms (7.0 +/- 6.9 vs. 3.9 +/- 4.6 days, p 0.0002), and had higher erythrocyte sedimentation rates (45 +/- 22 vs. 33 +/- 22 mm/h, p < 0.02) and lactate dehydrogenase values (924 +/- 113 vs. 685 +/- 165 IU/L, p 0.001). There was a trend in bacteraemic children towards immunosuppression (6.3% vs. 1.0%, p 0.08) and a lower number of siblings (2.9 +/- 1.9 vs. 3.8 +/- 2.7, p 0.063). Non-bacteraemic children had a more severe clinical appearance, and a higher percentage had a moderate to bad general appearance (51.5 vs. 29.7%, p < 0.01), with dehydration (37.1 vs. 18.8%, p 0.02) and vomiting (58.8 vs. 39.0%, p 0.02). Laboratory dehydration indicators were also markedly worse in non-bacteraemic children, with urine specific gravity of 1020 +/- 9.4 vs. 1013 +/- 9.0 (p 0.0002), base excess of - 4.2 +/- 3.0 vs. - 2.5 +/- 3.4 mEq/L (p 0.01), and blood urea nitrogen of 10.1 +/- 7.0 vs. 7.4 +/- 4.5 mg% (p 0.002). Thus, the clinical presentation of bacteraemic children was more gradual, and associated gastroenteritis and dehydration was less pronounced. These findings may contribute in part to the inadvertent discharge of bacteraemic children from the emergency department.

Blood cultures in ambulatory outpatients

Background

Blood cultures are a gold standard specific test for diagnosing many infections. However, the low yield may limit their usefulness, particularly in low-risk populations. This study was conducted to assess the utility of blood cultures drawn from ambulatory outpatients.

Methods

Blood cultures drawn at community-based collection sites in the Calgary Health Region (population 1 million) in 2001 and 2002 were included in this study. These patients were analyzed by linkages to acute care health care databases for utilization of acute care facilities within 2 weeks of blood culture draw.

Results

3102 sets of cultures were drawn from 1732 ambulatory outpatients (annual rate = 89.4 per 100,000 population). Significant isolates were identified from 73 (2.4%) sets of cultures from 51 patients, including Escherichia coli in 18 (35%) and seven (14%) each of Staphylococcus aureus and Streptococcus pneumoniae. Compared to patients with negative cultures, those with positive cultures were older (mean 49.6 vs. 40.1 years, p < 0.01), and more likely to subsequently receive care at a regional emergency department, outpatient antibiotic clinic, or hospital (35/51 vs. 296/1681, p < 0.0001). Of the 331 (19%) patients who received acute care treatment, those with positive cultures presented sooner after community culture draw (median 2 vs. 3 days, p < 0.01) and had longer median treatment duration (6 vs. 2 days, p < 0.01).

Conclusion

Blood cultures drawn in outpatient settings are uncommonly positive, but may define patients for increased intensity of therapy. Strategies to reduce utilization without excluding patients with positive cultures need to be developed for this patient population.

Hemocultivos en el servicio de urgencias

INTRODUCTION

Culture of emergency room blood samples is common practice, but open to controversy. As compared to other emergency tests, blood collection requires twice as much time and needs a refined technique to avoid contamination, and the study has no immediate diagnostic utility.

METHODS

This prospective study includes consecutive adult patients with positive emergency room blood cultures. We analyzed the diagnostic sensitivity and contamination rate of the cultures and the etiology, clinical features and prognosis of the bacteremias encountered.

RESULTS

During the study period, 5.2 blood cultures were indicated per 1000 patients attended in the emergency room. The diagnostic yield (positive blood cultures/total cultures) was 20% and the contamination rate (contaminated blood cultures/total cultures) was 1%. The incidence of bacteriemia was 0.99 episodes per 1000 patients attended in the emergency room and 10.3 episode per 1000 hospitalized patients. Gram-negative bacteria predominated (57%). Sepsis was the most frequent clinical manifestation (50%), followed by severe sepsis (40%) and septic shock (10%). Mortality was 22%. Diabetes mellitus and severe sepsis/septic shock were independent factors associated with mortality.

CONCLUSIONS

Diagnostic performance and quality of emergency room blood cultures was high. The predominant etiology was gram-negative bacteria. Patients had a severe clinical presentation. Diabetes mellitus and severe sepsis and/or septic shock were independent prognostic factors of mortality.

Demographic and clinical characteristics of patients admitted to medical departments

INTRODUCTION

The significant changes, which have affected departments of medicine over the last two decades, have been much editorialized. Surprisingly few data have been published that document these changes. We describe the demographic and clinical characteristics of patients admitted to one hospital's departments of internal medicine.

METHODS

During a 3 months prospective study, 1039 patients (46% of all 2277 new admissions to the departments of medicine, consisting of +/- 175 beds) were randomized for inclusion. Information was extracted from the medical records regarding demography; functional capacity; clinical data and outcome.

RESULTS

The mean age of the patients was 72 +/- 16 years (mean +/- SD); 51% were male, 56% were married, and 83% lived at home. Although 293 patients (28%) were defined as dependent, the majority lived at home (170, 58%). Cognition was normal in only 74%. The four most common disease categories leading to admission were infections (383 patients, 37%), cardiovascular disorders (372, 36%), respiratory conditions (284, 27%) and genito-urinary problems (90, 9%). Overall, 98 persons died (9%). Independent risk factors for death were: mechanical ventilation; a 'do not resuscitate' order; a high APACHE-II score; a low serum albumin level; higher age; and not being married (P < 0.01).

CONCLUSIONS

Geriatric patients occupy a central position in our medical wards. These data are relevant for allocation of special resources for departments with high proportions of geriatric patients; for the design of employment conditions that ascertains continuing job satisfaction; as well as for the planning of teaching opportunities for residents and students.

Epidemiological and clinical characteristics of occult bacteremia in an adult emergency department in Spain: influence of blood culture results on changes in initial diagnosis and empiric antibiotic treatment

A prospective study was carried out to analyze the usefulness of blood culture results for adult patients who were discharged from the emergency department with bacteremia. Over a 29-month period, 110 patients with significant bacteremia who were seen in the emergency department and discharged home were studied. The mean age of the patients was 61.8 years. The most frequent initial major diagnosis was urinary tract infection (UTI) (n=63; 57.3%). Gram-negative organisms were isolated in 79 (71.8%) cases. A change in diagnosis (44.5% cases) was more common when the initial diagnosis was something other than UTI or when empiric antimicrobial therapy was ineffective or was not given (P<0.001). The significant predictors of modification of the initial empiric antibiotic therapy were ineffective empiric antimicrobial therapy and transfer of the patient from the emergency department to an infectious diseases outpatient clinic (P=0.01). Blood culture results may be useful for achieving the correct diagnosis in adult patients with bacteremia and for guiding treatment in the subsequent management of outpatients.

Failure of macrolide antibiotic treatment in patients with bacteremia due to erythromycin-resistant Streptococcus pneumoniae

The rate of macrolide resistance among Streptococcus pneumoniae is increasing, but some investigators have questioned its clinical relevance. We conducted a matched case-control study of patients with bacteremic pneumococcal infection at 4 hospitals to determine whether development of breakthrough bacteremia during macrolide treatment was related to macrolide susceptibility of the pneumococcal isolate. Case patients (n=86) were patients who had pneumococcal bacteremia and an isolate that was either resistant or intermediately resistant to erythromycin. Controls (n=141) were patients matched for age, sex, location, and year that bacteremia developed who had an erythromycin-susceptible pneumococcus isolated. Excluding patients with meningitis, 18 (24%) of 76 case patients and none of 136 matched controls were taking a macrolide when blood was obtained for culture (P=.00000012). Moreover, 5 (24%) of 21 case patients with the low-level-resistant M phenotype and none of 40 controls were taking a macrolide (P=.00157). These data show that development of breakthrough bacteremia during macrolide or azalide therapy is more likely to occur among patients infected with an erythromycin-resistant pneumococcus, and they also indicate that in vitro macrolide resistance resulting from both the efflux and methylase mechanisms is clinically relevant.