Black and White Patients With Staphylococcus aureus Bacteremia Have Similar Outcomes but Different Risk Factors.

BACKGROUND: Staphylococcus aureus bacteremia (SAB) disproportionately affects Black patients. The reasons for this disparity are unclear. METHODS: We evaluated a prospectively ascertained cohort of patients with SAB from 1995 to 2020. Clinical characteristics, bacterial genotypes, and outcome were compared among Black and White patients with SAB. Multivariable logistic regression models were used to determine factors independently associated with the outcomes. RESULTS: Among 3068 patients with SAB, 1107 (36%) were Black. Black patients were younger (median, 56 years vs 63 years; P < .001) and had higher rates of diabetes (47.5% vs 34.5%, P < .001), hemodialysis dependence (40.0% vs 7.3%, P < .001), and human immunodeficiency virus (6.4% vs 0.6%, P < .001). Black patients had higher rates of methicillin-resistant S. aureus (49.3% vs 44.9%, P = .020), including the USA300 hypervirulent clone (11.5% vs 8.4%, P = .007). White patients had higher rates of corticosteroid use (22.4% vs 15.8%, P < .0001) and surgery in the preceding 30 days (28.1% vs 18.7%, P < .001). Although the median Acute Physiology Score (APS) at the time of initial SAB diagnosis was significantly higher in Black patients (median APS, 9; interquartile range [IQR], 5-14 vs median APS, 7; IQR, 4-12; P < .001), race was not associated with 90-day mortality (risk ratio, 1.02; 95% confidence interval, .93-1.12), and rates of metastatic infection were lower among Black patients (37.2% vs 41.3% White, P = .029). CONCLUSIONS: Despite differences in Black patients' higher APS on presentation and more risk factors, including a 5 times higher risk of hemodialysis dependence, 90-day mortality among Black and White patients with SAB was similar.

Healthcare-associated Staphylococcus aureus bacteraemia: time to reduce the harm caused by a largely preventable event.

Staphylococcus aureus disease is associated with significant morbidity and mortality and of concern, it disproportionally affects Maori and Pacific Peoples. New Zealand has high rates of skin and soft tissue infection caused by S. aureus. Healthcare-associated S. aureus bacteraemia (HA-SAB) accounts for a significant proportion of all S. aureus bacteraemia events. Measurement of HA-SAB has been reported in New Zealand for over 20 years but it has not been linked to quality improvement interventions to reduce the rate. It has been used as an outcome measure for the Hand Hygiene New Zealand programme; however, a recent review of submitted data questioned the accuracy of it. This has been addressed. National programmes such as the Health Quality & Safety Commissions Hand Hygiene New Zealand and the Surgical Site Infection Improvement programme have led to reduced harm from healthcare-associated infections. Interventions targeted at reducing the HA-SAB rate, such as bundles of care for insertion and maintenance of vascular access devices and skin and nasal decolonisation of staphylococci prior to surgery, are urgently required.

Development of a Clinical Prediction Model for Central Line-Associated Bloodstream Infection in Children Presenting to the Emergency Department.

OBJECTIVE: The majority of the children with a central line who present to the emergency department with fever or other signs of bacteremia do not have a central line-associated bloodstream infection (CLABSI). Our objective was to develop a clinical prediction model for CLABSI among this group of children in order to ultimately limit unnecessary hospital admissions and antibiotic use. METHODS: We performed a nested case-control study of children with a central line who presented to the emergency department of an urban, tertiary care children's hospital between January 2010 and March 2015 and were evaluated for CLABSI with a blood culture. RESULTS: The final multivariable model developed to predict CLABSI consisted of 12 factors: age younger than 5 years, black race, use of total parenteral nutrition, tunneled central venous catheter, double-lumen catheter, absence of other bacterial infection, absence of viral upper respiratory tract infection symptoms, diarrhea, emergency department temperature greater than 39.5°C, fever prior to presentation, neutropenia, and spring/summer season. The clinical prediction score had good discrimination for CLABSI with a c-statistic of 0.81 (confidence interval, 0.77-0.85). A cut point less than 6 was associated with a sensitivity of 98.5% and a negative predictive value of 99.2% for CLABSI. CONCLUSIONS: We were able to identify risk factors and develop a clinical prediction model for CLABSI in children presenting to the emergency department. Once validated in future study, this clinical prediction model could be used to assess the need for hospitalization and/or antibiotics among this group of patients.

Hospital-Onset MRSA Bacteremia Rates Are Significantly Correlated With Sociodemographic Factors: A Step Toward Risk Adjustment.

The correlations between census-derived sociodemographic variables and hospital-onset methicillin-resistant Staphylococcus aureus bacteremia (HO-MRSAB) rates were examined at the US state level. On multivariable analysis, only percent African American remained statistically significant. This finding highlights an important disparity and suggests that risk adjustment is needed when comparing HO-MRSAB rates among US states. Infect Control Hosp Epidemiol 2018;39:479-481.

Hematologic Manifestations of Brucellosis in Children.

BACKGROUND: Brucellosis is a common zoonosis in the Bedouin population of southern Israel. Limited data exist for the rate and risk factors of hematologic complication of brucellosis in children. We assessed anemia, leukopenia, thrombocytopenia and pancytopenia in childhood brucellosis in southern Israel. METHODS: Our medical center is the sole hospital in southern Israel. All medical files of brucellosis, 2005-2014, identified through positive blood cultures or International Classification of Diseases 9th revision coding with positive serology, were reviewed retrospectively. RESULTS: Overall, 511 brucellosis episodes were identified; 42% (N = 214) with ≥1 cytopenia, including 13% (N = 68) anemia, 28% (N = 144) leukopenia, 14% (N = 74) thrombocytopenia and 2% (N = 9) pancytopenia. Overall, 99.8% of episodes were in Bedouin children and 70% in males. In 79% of episodes, blood culture was positive for Brucella melitensis. Acute infections comprised 84% of all episodes. In univariate analysis, older age (10.49 ± 4.81 vs. 9.25 ± 4.89 years), fever (92% vs. 78%), positive blood culture (84% vs. 75%) and IgM ≥1:640 levels (50% vs. 39%) were associated with cytopenia. In contrast, arthralgia was associated with noncytopenic episodes. In multivariate analyses, older age (odds ratio = 1.063) and fever (odds ratio = 3.127) were associated with cytopenia. CONCLUSIONS: Brucellosis is commonly presented with cytopenia, especially in bacteremic episodes with fever. However, pancytopenia is uncommon and its finding should alert the physician to look for other possible etiologies.

African American Race Is a Newly Identified Risk Factor for Postengraftment Blood Stream Infections in Pediatric Allogeneic Blood and Marrow Transplantation.

Blood stream infections (BSI) are a major source of morbidity and mortality both in allogeneic blood and marrow transplant (BMT) recipients. Various risk factors for BSI in BMT have been identified. The impact of race and cytomegalovirus (CMV) viremia, a common complication after engraftment, however, has not been rigorously assessed. This is important because both CMV infection and ganciclovir, the mainstay of pre-emptive therapy, have myelosuppressive and immunosuppressive effects. We conducted a retrospective analysis to test the hypothesis that race and CMV viremia predispose allogeneic BMT patients to postengraftment BSI. We analyzed 278 allogeneic BMT performed at Children's Healthcare of Atlanta between January 1, 2005 and December 31, 2014 that met eligibility criteria. We performed a multivariate analysis to estimate the effect of CMV viremia on risk for BSI in the postengraftment period (days +30 to 100). Risk for BSI was associated with CMV viremia (hazard ratio [HR], 3.34; 95% confidence interval [CI], 1.51 to 7.36; P = .003); grade III and IV acute graft-versus-host disease (HR, 3.28; 95% CI, 1.55 to 6.92; P = .002), and African American race (HR, 2.22; 95% CI, 1.09 to 4.51; P = .027). The results of our study highlight the importance of a novel risk factor for postengraftment BSI, not previously considered-African American race.

Streptococcus bovis Bacteremia: Association with Gastrointestinal and Liver Disease in a Predominantly Hispanic Population.

OBJECTIVES: Streptococcus bovis bacteremia has been associated with gastrointestinal diseases, especially colon cancer, neoplastic colon polyps, and other malignancies of the gastrointestinal tract. Studies have suggested an association with chronic liver parenchymal and biliary tract disorders. We report a series of patients with S. bovis bacteremia in a county hospital in a US city on the border of Mexico to examine the demographic and clinical associations. METHODS: We characterized the demographics, clinical features, and the endoscopic and histopathologic findings in all patients with blood cultures positive for S. bovis at University Medical Center in El Paso, Texas, between January 2000 and December 2010. Hospital records were systematically reviewed using a standardized protocol. RESULTS: A total of 21 episodes of S. bovis bacteremia were documented in 21 adult patients. The mean age was 61 (range 25-97), 12 were women, and 20 were Hispanic. Presenting illnesses in these patients were gastrointestinal bleed (4), sepsis (4), cholangitis (3), hepatic encephalopathy (2), altered mental status (2), spontaneous bacterial peritonitis (1), septic abortion (1), diarrhea (1), others (3). Chronic liver disease was present in 7 cases (33%), 6 of which were alcohol related (5 with concomitant hepatitis C infection). Infective endocarditis was found in 1 patient. Overall, 10 patients underwent either colonoscopy alone (3), upper endoscopy alone (3), or both (4), and 2 underwent endoscopic retrograde cholangiopancreatography. Of the 7 (33%) patients who had colonoscopy, pathology was identified in 4 of them, including colon polyps in 3 (43%) and colitis in 1 (14%). Mortality was 19% (4 patients). CONCLUSIONS: Our finding in a series of predominantly Hispanic patients with S. bovis bacteremia in a county hospital setting was consistent with the previously reported association with gastrointestinal disease. Findings on colonoscopy included colonic polyps and colitis, although no cases of colon cancer were found. Chronic liver disease was a common concurrent illness and cholangitis also occurred. There was a significant mortality rate in adults.

Demographic and clinical characteristics of Campylobacter bacteremia in children with and without predisposing factors.

BACKGROUND: Campylobacter, a common cause of childhood gastroenteritis, rarely causes bacteremia, which is reported mainly in immune-compromised children. Our aim was to compare demographic and clinical characteristics of childhood campylobacter bacteremia (CB) between children with and without risk factors for CB. METHODS: A retrospective, population-based study, conducted between 1989 and 2010. Risk factors were defined as immunodeficiency, malignancy, extreme prematurity or chronic diseases with malnutrition. RESULTS: Seventy-six CB episodes (1 per child/month) were identified in 14 children with risk factors (30 episodes) and 46 children without risk factors (46 episodes). Children with risk factors were older (mean age 120.0±72.8 vs. 16.2±27.6 months) with higher proportion of males (90.0% vs. 60.9%), less gastrointestinal symptoms (43.3% vs. 69.9%) and higher hospitalization rates (96.7% vs. 69.6%) compared with children without risk factors. Campylobacter jejuni and Campylobacter coli (46/47 of identified species) were the most common species in both groups. Positive campylobacter stool cultures were found only in children without risk factors (0% vs. 38.5%). No mortality cases were observed. All isolates tested for antibiotic susceptibility were sensitive to macrolides and carbapenems. CONCLUSIONS: Childhood CB is rare in southern Israel. The disease manifests as a single gastroenteritis complication in a previously healthy young child or as recurrent episodes in an older, immune-compromised child, usually without gastrointestinal symptoms. This disparity may reflect pathogenesis differences, with disease in the immune-competent being dependent on pathogen virulence, whereas disease in the immune-compromised being host dependent. Disease outcome is usually favorable, and macrolides remain the antibiotic treatment of choice.

An investigation of the frequency of bacteraemia following dental extraction, tooth brushing and chewing.

We conducted a study to determine the frequency of bacteraemias following dental extraction and common oral procedures, namely tooth brushing and chewing, and the relationship between bacteraemia and oral health in black patients. Positive blood cultures were detected in 29.6% of patients after dental extraction, in 10.8% of patients after tooth brushing and in no patients after chewing. No relationship between the state of oral health, which was assessed using the plaque and gingival indices, and the incidence of bacteraemia was found. The duration of bacteraemia was less than 15 minutes. One patient had a positive blood culture prior to dental extraction; his oral health status was poor. Our study confirmed that bacteraemia occurs after tooth brushing.

Maternal sepsis: a Scottish population-based case-control study.

OBJECTIVE: To describe the risk of maternal sepsis associated with obesity and other understudied risk factors such as operative vaginal delivery. DESIGN: Population-based, case-control study. SETTING: North NHS region of Scotland. POPULATION: All cases of pregnant, intrapartum and postpartum women with International Classification of Disease-9 codes for sepsis or severe sepsis recorded in the Aberdeen Maternal and Neonatal Databank (AMND) from 1986 to 2009. Four controls per case selected from the AMND were frequency matched on year-of-delivery. METHODS: Cases and controls were compared; significant variables from univariable regression were adjusted in a multivariable logistic regression model. MAIN OUTCOME MEASURES: Dependent variables were uncomplicated sepsis or severe ('near-miss') sepsis. Independent variables were demographic, medical and clinical delivery characteristics. Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals (95% CI) are reported. RESULTS: Controlling for mode of delivery and demographic and clinical factors, obese women had twice the odds of uncomplicated sepsis (OR 2.12; 95% CI 1.14-3.89) compared with women of normal weight. Age <25 years (OR 5.15; 95% CI 2.43-10.90) and operative vaginal delivery (OR 2.20; 95% CI 1.02-4.87) were also significant predictors of sepsis. Known risk factors for maternal sepsis were also significant in this study (OR for uncomplicated and severe sepsis respectively): multiparity (OR 6.29, 12.04), anaemia (OR 3.43, 18.49), labour induction (OR 3.92 severe only), caesarean section (OR 3.23, 13.35), and preterm birth (OR 2.46 uncomplicated only). CONCLUSIONS: Obesity, operative vaginal delivery and age <25 years are significant risk factors for sepsis and should be considered in clinical obstetric care.

Staphylococcus aureus bacteraemia at Alice Springs Hospital, Central Australia, 2003-2006.

BACKGROUND: Infectious diseases remain the leading cause of death at Alice Springs Hospital (ASH) and Staphylococcus aureus bacteraemia (SAB) is the second most common bloodstream infection. Non-multidrug-resistant, methicillin-resistant S. aureus (nmMRSA) is endemic to the region. AIMS: To determine whether differences exist between racial groups and resistance phenotypes in the clinical manifestations and outcomes of SAB at ASH. METHODS: A retrospective review of medical and pathology records for inpatients with SAB between 1 January 2003 and 31 December 2006. RESULTS: A total of 125 patients (indigenous, 111; non-indigenous, 14) presented with SAB during the study period. Among indigenous patients, there were 95 adults and 16 children. No non-indigenous child was admitted with SAB. The mean annual incidence rate was 160.7/100 000 indigenous population and 8.1/100 000 non-indigenous population (incidence rate ratio 19.9) (P = 0.010). Isolates were predominantly methicillin-susceptible S. aureus (indigenous, 85; non-indigenous, 13). Twenty of 27 MRSA isolates were non-multidrug-resistant. Indigenous adults were more likely to present with an infective focus (indigenous, 75; non-indigenous, 6) (P = 0.004). These were most often skin infections (skin abscesses, 31; scabies, 4). Twenty-seven indigenous adults self-discharged after receiving a median of only 5 days (inter-quartile range (IQR), 3-9) of antibiotic therapy. Ninety-day mortality rates for indigenous and non-indigenous adults were 14.7% and 14.3% respectively. The median age of death for indigenous adults was 50 years (IQR, 37-68). CONCLUSIONS: Indigenous Australians have the highest reported incidence rate of SAB worldwide. This reflects the socioeconomic disadvantage experienced by indigenous Australians whose living conditions predispose to pathogen transmission and limits opportunities to maintain adequate skin hygiene.

Nasal carriage of Staphylococcus aureus in healthy Aucklanders.

BACKGROUND: Studies have reported higher rates of diseases caused by Staphylococcus aureus (S. aureus) amongst Maori and Pacific people, compared with people of other ethnicities. AIM: We aimed to estimate the prevalence of nasal carriage and to explore demographic differences between S. aureus carriers and non-carriers in Auckland, New Zealand. MATERIALS AND METHODS: Nasal swab specimens were obtained from healthy population volunteers, who did not have recent healthcare contact. Each participant completed a short questionnaire. RESULTS: 78/424 (18%; 95%CI, 15-22) S. aureus carriers were identified. Female participants were less likely to be S. aureus carriers than males; but there were no differences in the ages or ethnic groups between S. aureus carriers and non-carriers. Socioeconomic deprivation, recent non-hospital healthcare contact and past history of S. aureus infection were not associated with S. aureus carriage. CONCLUSION: Ethnic variation in the prevalence of S. aureus nasal carriage does not contribute to an increased risk of disease caused by S. aureus.

Bacteraemia caused by beta-haemolytic streptococci in North Queensland: changing trends over a 14-year period.

Group A streptococci (GAS) are usually the predominant species in cases of bacteraemia caused by ß haemolytic streptococci (BHS). An increasing worldwide incidence of invasive disease from non-group A BHS has been reported. Little is known about the changing trends in invasive disease caused by BHS in Australia. North Queensland has a relatively large indigenous population, who experience significantly higher rates of group A-related disease than the non-indigenous population. This prospective study examined changing trends of disease from large colony BHS that group with A, B, C and G antisera over a 14-year period at the single large tertiary referral hospital in the area. We identified 392 bacteraemic episodes caused by BHS. GAS were most commonly isolated (49%), with adjusted rates remaining stable over the period. There was a significant increase in the incidence of non-neonatal bacteraemia caused by group B streptococci (GBS) over the study period (r = 0.58; p 0.030), largely driven by infection in older, non-indigenous women. Rates of bacteraemia caused by group C streptococci also experienced a modest, but significant, increase over time (r = 0.67; p 0.009). GAS, which had no predominant emm type, were seen most commonly in indigenous subjects (52%). Mortality rates ranged from 3.2% (group G) to 10.3% (group C), with a rate of 7.9% associated with group A disease. The marked rise in GBS disease has been noted worldwide, but the relatively low incidence in indigenous Australian patients has not been described before, despite the burden of well-recognized risk factors for GBS disease within this group.

Bacteremia and septicemia in diabetic patients in Western Saudi Arabia.

OBJECTIVE: The present study aims to define the pattern of bacteremia with clinical sepsis in diabetic patients at King Abdul-Aziz University Hospital (KAUH), Jeddah, Kingdom of Saudi Arabia (KSA), in relation to the type of infection, microbial pattern, source, complication, outcome, and the risk factors associated with high mortality. METHODS: Retrospective study of adult diabetic patients with bacteremia and septicemia admitted to KAUH during a 2 years period between January 2000 through to December 2002 was carried out. RESULTS: A total of 4850 blood culture were submitted to the Microbiology Laboratory of KAUH over a 2 years period. Two hundred and ninety (6%) cases had positive blood cultures, 70 were diabetic patients with an incidence rate of 24% with p-value of 0.043 which is statically significant. Urinary tract infection was the most common source of bacteremia in our study group with Escherichia coli as the most frequent organism in 62%. Mortality rate was 44%. Old age was an important risk factors for high mortality with p-value 0.011, which is statically significant. Other risk factors included comorbidity associated with diabetes, septic shock, mechanical ventilation and disseminated intravascular coagulation. CONCLUSION: Increase age was one of the important risk factors for high mortality rate in our study group. Good empiric antibiotics coverage should be instituted early in high risk groups.

Clinical and epidemiological features of group A streptococcal bacteraemia in a region with hyperendemic superficial streptococcal infection.

Reports of increasing incidence and severity of invasive group A streptococcal (GAS) infections come mainly from affluent populations where exposure to GAS is relatively infrequent. We conducted a 6-year retrospective review of GAS bacteraemia in the Northern Territory of Australia, comparing the Aboriginal population (24% of the study population), who have high rates of other streptococcal infections and sequelae, to the non-Aboriginal population. Of 72 episodes, 44 (61%) were in Aboriginal patients. All 12 cases in children were Aboriginal. Risk factors were implicated in 82% of episodes (91% in adults) and there was no significant difference in the proportion of Aboriginal compared to non-Aboriginal patients with at least one risk factor. Genetic typing of isolates revealed no dominant strains and no evidence of a clone which has been a common cause of these infections elsewhere.

Risk factors for invasive disease caused by Streptococcus pneumoniae among Alaska native children younger than two years of age.

Streptococcus pneumoniae causes a significant amount of illness and death from pneumonia, bacteremia and meningitis among children < 2 years of age. No currently available effective vaccine exists to prevent pneumococcal disease in this age group. To identify modifiable risk factors we conducted a retrospective case-control study of 29 Alaska Native residents of Bethel, AK, < 2 years of age who had invasive pneumococcal illness from 1983 to 1992 and 85 controls matched for race, city of residence and date of birth. Data were collected through reviews of medical records and telephone interviews. In matched univariate analysis the following variables were associated with illness at P < or = 0.25 and were included in the multivariate model: at least one prior episode of pneumonia; at least one prior hospitalization; group child care center attendance; at least one tobacco smoker in the household; at least one tobacco chewer in the household; and lack of breast-feeding. Using a conditional multiple logistic regression analysis, we found that group child care center attendance (odds ratio, 98.6; 95% confidence interval, 5.1 to 1920.6) and the presence in the household of at least one person who chewed tobacco (odds ratio, 20.6; 95% confidence interval, 1.4 to 294.5) were independently associated with illness while breast-feeding was protective (odds ratio, 0.1; 95% confidence interval, 0.0 to 1.0). These data suggest that breast-feeding may prevent invasive pneumococcal disease and that strategies for decreasing risks should target children in group child care settings. Further studies are needed to evaluate the interaction of tobacco and pneumococcal illness.

The epidemiology of invasive pneumococcal disease in Alaska, 1986-1990--ethnic differences and opportunities for prevention.

To assess prevention strategies for pneumococcal disease in Alaska, prospective surveillance during 1986-1990 identified 672 invasive pneumococcal infections, including 315 among Alaska Natives. Age-adjusted annual incidence was 74 per 100,000 for Alaska Natives and 16 per 100,000 for nonnatives. The annual incidence in Alaska Native children < 2 years old was 624 per 100,000; rates of 84 per 100,000 for meningitis and 290 per 100,000 for bacteremic pneumonia were 8-10 times higher than for other US groups. By age 75, cumulative incidence (7%) and mortality (1%) in Alaska Natives were almost 4 times higher than for nonnatives. Only 17% of Alaska Native adults with predisposing conditions and invasive infections previously received pneumococcal vaccine. For Alaska Natives, a proposed heptavalent conjugate pneumococcal vaccine will include serotypes responsible for 85% of invasive isolates from children < 2 years but only 32% of those from adults. The 23-valent polysaccharide pneumococcal vaccine, which contains > 94% of serotypes identified in Alaska Native toddlers and adults, should be used more widely.