Israel Medical Association Journal

Background: Gram-negative bloodstream infections (GN-BSI) are life threatening. Appropriate antimicrobial therapy and source control when indicated improve survival. Dementia is an independent risk factor for death and is associated with increased risk for infections, especially in advanced stages. Data about the best diagnostic and therapeutic approaches for patients with dementia and GN-BSI are lacking.

Objectives: To evaluate patients with dementia and GN-BSI and determine whether diagnostic imaging improves clinical outcomes.

Methods: We performed a retrospective cohort study of adult patients with GN-BSI, during 2019–2022. Patients with or without a diagnosis of dementia were compared. Outcomes were in-hospital mortality and recurrent bacteremia. Demographic, clinical, diagnostic, and therapeutic data were collected and analyzed.

Results: A total of 87 patients with dementia and 130 without were included. Patients with dementia received appropriate empirical antimicrobial therapy in 38% of cases compared to 62% of patients without dementia, P < 0.001. Imaging studies were performed in half of patients in both groups. In the dementia group, 17% had abnormal findings that required source control versus 30% in the control group (P = 0.049). Source control was performed in 15% of patients with dementia versus 28% of patients without dementia (P = 0.032). Mortality was 27.6% in the dementia group versus 22.3% in the control group (P = 0.42).

Conclusions: In patients with dementia and GN-BSI, imaging studies have lower effect on clinical outcomes. Imaging studies should be performed in selected cases only and not conducted routinely.

Coronavirus disease 2019 (COVID-19), first identified in 2019, constitutes a global major public health burden. Most of morbidity and mortality is derived by the severe inflammatory reaction (cytokine release syndrome) that ensues in later stages. Baricitinib, a selective JAK inhibitor primarily used for the treatment of rheumatoid arthritis (RA) [1], was shown to reduce mortality in COVID-19 hospitalized patients in combination with remdesivir [2].

A 70-year-old male arrived at the emergency department (ED) with symptoms of fever, shivering, and sweating for 3 days. A dry cough started a week before admission. There were no other referring symptoms. The patient, a farmer by occupation, denied any animal bite or exposure, travel abroad, consumption of uncooked meat, or drink of unpasteurized milk products. In the ED, his vital signs showed hypotension with blood pressure of 70/40 mmHg, pyrexia of 39.4°C, and tachycardia of 100 beats per minute. On physical examination, the patient shivered. On auscultation, fast heart sounds were heard.

Background: Antibiotic stewardship programs are necessary to test the appropriateness of local guidelines for empirical antibiotic treatment by audits.

Objectives: To assess whether compliance to local guidelines achieved a higher rate of appropriate antibiotic treatment and reduced morbidity and mortality, and whether infectious disease counseling improved the rate of appropriate treatment.

Methods: Our cohort comprised 294 patients with proven bacteremia. Data were retrieved from medical records including diagnosis, empiric antibiotic treatment, and outcomes.

Results: The empirical treatment was consistent with bacterial susceptibility in 227 patients (77%), and matched in 64% of the time to the first line, and another 24% to the second line of institutional guidelines. A strong correlation was found between appropriate empiric treatment according to bacterial susceptibility and reduced mortality (odds ratio [OR] 0.403, P = 0.007). A similar correlation was found with the choice of appropriate antibiotics according to local guidelines (OR 0.392, P = 0.005). Infectious disease consultation was related to an increase in the rate of appropriateness of treatment according to guidelines (85% vs.76%, P = 0.005). A tendency to increased appropriateness was related to microbial susceptibility (87% vs. 74%, P = 0.07).

Conclusions: In this study, initiation of appropriate empiric antibiotic therapy, according to the hospital's guidelines, was found associated with reduced mortality in patients with bacteremia.

Background: Recent data regarding polymicrobial bacteremia (PMB) are lacking.

Objectives: To characterize risk factors as well as clinical, microbiological, and prognostic patterns of patients with PMB in a modern hospital setting.

Methods: A single center retrospective study including all patients diagnosed with PMB during 2013 was conducted. PMB was defined as two or more organisms cultured from the blood of the same patient within 72 hours. Patients with monomicrobial infections served as controls.

Results: There were 135 episodes (2% of all bacteremia episodes) of true PMB among 123 patients during the study period. Recent invasive procedures (odds ratio [OR] 3.59, 95% confidence interval [95%CI] 1.41–9.12, P = 0.006) and foreign bodies (OR 1.88, 95%CI 1.06–3.33, P = 0.04) were risk factors for PMB when compared with 79 patients with monomicrobial bacteremia. Central-line-associated infections were the most common infection source among patients with PMB (n=34, 28%). Enterobacteriaceae were the most commonly implicated pathogen (n=95, 77%). Non-fermenting Gram-negative bacilli were significantly more common than previously reported (n=55, 45%). Although crude 30-day mortality was higher (48% vs. 33%) in PMB patients, adjusted mortality was comparable in the two groups.

Conclusions: PMB rate in our cohort was considerably lower than in previous reports. Central-line-associated infections were more common than classic PMB sources. Mortality remained high. Strategies for early identification and better care for these patients should be pursued.

Background: The introduction of pneumococcal conjugate vaccine-13 (PCV-13) has reduced the burden of invasive pneumococcal disease.

Objective: To characterize true positive blood cultures of children who presented to our hospital following implementation of the PCV-13 vaccine.

Methods: A retrospective study was conducted on positive blood cultures of children presenting with fever from 2010–2017. Subjects were divided into two age groups: a younger group 3–36 months and an older group 3–18 years. Patients were classified as either having or not having a focus of infection at the time of their bacteremia. Pneumococcal isolates were typed at Israel's Streptococcal Reference Laboratory.

Results: The samples included 94 true positive blood cultures. Focal infection with concomitant bacteremia was more common than bacteremia without a focus both overall: 67/94 (71%) vs. 27/94 (28.7%), P <0.001 as well as in the two groups: 32/48 (66%) vs. 16/48 (33%), P = 0.02 in the younger group and 35/46 (76%) vs. 11/46 (24%), P = 0.001 in the older group. Streptococcus pneumoniae was the most common pathogen overall, 27/94 (29%), and in the younger group, 21/48 (44%), but rare in the older group, 6/46 (13%). In the latter, Brucella species predominated, 12/46 (26%), along with Staphylococcus aureus 12/46 (26%).

Conclusions: Our findings are consistent with other studies reporting decreased pneumococcal bacteremia, bacteremia primarily accompanying focal infection, and changing etiological agents among PCV-13-vaccinated children. Brucella species was prominent in older children with osteoarticular infections. Ongoing surveillance is warranted to better understand the implications of PCV-13.

Background: Skin colonization of microorganisms in blood cultures (BCs) are generally considered clinically non-significant and can be the source of a true infection, particularly in immunosuppressed patients.

Objectives: To study the epidemiology and risk factors for bacteremia caused by contaminants.

Methods: This retrospective, descriptive study is based on adult BCs collected (2004–2013) and categorized as positive (True bacteremia [TrueB] or contamination) or negative. Clinical, demographic, and laboratory characteristics of BCs positive for the six most common potential contaminant pathogens (PCPs) that can cause TrueB and contamination (Coagulase-negative Staphylococcus [CoNS], Streptococcus viridans, Propionibacterium acnes, Corynebacterium spp., Bacillus spp., Clostridium spp.) were assessed. Ninety-two TrueB were identified vs. 196 contaminations (1:2 ratio).

Results: From 74,014 BCs, PCPs were found in 3735 samples, of which 3643 (97.5%) were contaminations and 92 (2.5%) were TrueB. The overall rate of BC contamination decreased during the study period from 6.7% to 3.8%. CoNS was the most common PCP. Bacillus spp. were only contaminants. Clostridium spp. and Streptococcus viridans were more often TrueB. In a multivariate model, predictors of TrueB included high creatinine levels, Streptococcus viridans in BC, and multiple positive BCs. A single culture of CoNS was strongly predictive of contamination.

Conclusions: Ten years of data on BCs, focusing on six PCPs, demonstrates a significant, yet insufficient reduction in the rate of contamination. High creatinine level, isolation of Streptococcus viridans, and multiple positive BCs were predictors of TrueB, while growth of CoNS was strongly predictive of contamination. This model could assist in diagnostic and therapeutic decision making.

Background: Increasing antibiotic resistance in the community results in greater use of empiric broad spectrum antibiotics for patients at hospital admission. As a measure of antibiotic stewardship it is important to identify a patient population that can receive narrow spectrum antibiotics.

Objectives: To evaluate resistance patterns of Escherichia coli bloodstream infection (BSI) from strictly community-acquired infection and the impact of recent antibiotic use on this resistance.

Methods: This single center, historical cohort study of adult patients with E. coli BSI was conducted from January 2007 to December 2011. Patients had no exposure to any healthcare facility and no chronic catheters or chronic ulcers. Data on antibiotic use during the previous 90 days was collected and relation to resistance patterns was assessed.

Results: Of the total number of patients, 267 BSI cases met the entry criteria; 153 patients (57%) had bacteria sensitive to all antibiotics. Among 189 patients with no antibiotic exposure, 61% of isolates (116) were pan-sensitive. Resistance to any antibiotic appeared in 114 patients and 12 were extended-spectrum beta-lactamase (ESBL) producers. Quinolone use was the main driver of resistance to any antibiotic and to ESBL resistance patterns. In a multivariate analysis, older age (odds ratio 1.1) and quinolone use (odds ratio 7) were independently correlated to ESBL.

Conclusions: At admission, stratification by patient characteristics and recent antibiotic use can help personalize primary empirical therapy.

Background: Once a well-recognized entity, occult bacteremia (OB) is no longer a significant or serious bacterial infection. First following the introduction of the Haemophilus influenzae type B vaccine and now with the implementation of the conjugate pneumococcal vaccine (PCV), the number of cases has declined significantly. This has led to a change in many published guidelines to avoid taking blood cultures in fully vaccinated children presenting with fever. In Israel, the introduction of the PCV13 is now widespread. 

Objectives: To assess the incidence and outcome of OB, specifically by Streptococcus pneumoniae, in a single large pediatric medical center. 

Methods: We conducted a retrospective review of all cases of pneumococcal bacteremias in the years 2008–2013 and specifically those considered occult. 

Results: Of 355 cases of bacteremia diagnosed during the study period, 164 were caused by S. pneumoniae and 20 (12.8%) were considered occult. None of the OB cases had any complications. OB was not found in children over the age of 36 months. There was a change in the serotypes involving pneumococcal OB. 

Conclusions: OB is uncommon in the PCV-vaccinated population and the serotypes involved have changed.

 

Objectives: To add new cases of septicemia after rotavirus to the literature, review the few cases of septicemia after rotavirus that have been reported, calculate the incidence of septicemia in children hospitalized for rotavirus gastroenteritis, and discuss the characteristics of septicemia after rotavirus infection and implications for current pediatric practice.

Methods: We identified children whose illness was complicated by septicemia from among all hospitalizations at our facility for rotavirus gastroenteritis from May 1999 through May 2010. We also review the few cases reported in the English literature. 

Results: We identified two cases of septicemia from among 632 hospitalizations for rotavirus gastroenteritis in this time period, for an incidence rate of 0.32%, which is comparable to other estimates in the English literature. The typical course for cases of bacterial superinfection involves a second peak of high fever; other clinical signs are variable.

Conclusions: Septicemia after rotavirus gastroenteritis is a rare but dangerous entity. Early identification of a child developing bacterial superinfection after rotavirus, as in any case of sepsis, is of the utmost importance, as is obtaining blood cultures in a child with a rotavirus infection and a second fever spike.