Nam Su Ku

RED BLOOD CELL DISTRIBUTION WIDTH IS AN INDEPENDENT PREDICTOR OF MORTALITY IN PATIENTS WITH GRAM-NEGATIVE BACTEREMIA

ABSTRACT Red blood cell distribution width (RDW) is known to be a predictor of severe morbidity and mortality in some chronic diseases such as congestive heart failure. However, to our knowledge, little is known about RDW as a predictor of mortality in patients with Gram-negative bacteremia, a major nosocomial cause of intra-abdominal infections, urinary tract infections, and primary bacteremia. Therefore, we investigated whether RDW is an independent predictor of mortality in patients with Gram-negative bacteremia. Clinical characteristics, laboratory parameters, and outcomes of 161 patients with Gram-negative bacteremia from November 2010 to March 2011 diagnosed at Severance Hospital, Yonsei University College of Medicine, Seoul, Korea, were retrospectively analyzed. The main outcome measure was 28-day all-cause mortality. The 28-day mortality rate was significantly higher in the increased RDW group compared with the normal RDW group (P < 0.001). According to multivariate Cox proportional hazard analysis, RDW levels at the onset of bacteremia (per 1% increase, P = 0.036), the Charlson index (per 1-point increase, P < 0.001), and the Sequential Organ Failure Assessment score (per 1-point increase, P = 0.001) were independent risk factors for 28-day mortality. Moreover, the nonsurvivor group had significantly higher RDW levels 72 h after the onset of bacteremia than did the survivor group (P = 0.001). In addition, the area under the curve of RDW at the onset of bacteremia, the 72-h RDW, and the Sequential Organ Failure Assessment score for 28-day mortality were 0.764 (P = 0.001), 0.802 (P < 0.001), and 0.703 (P = 0.008), respectively. Red blood cell distribution width at the onset of bacteremia was an independent predictor of mortality in patients with Gram-negative bacteremia. Also, 72-h RDW could be a predictor for all-cause mortality in patients with Gram-negative bacteremia.

Measurement of plasma sTREM-1 in patients with severe sepsis receiving early goal-directed therapy and evaluation of its usefulness.

ABSTRACT The plasma level of soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) has been shown to be helpful in identifying critically ill patients with infection. However, it remains unknown whether it can be used to predict prognosis in patients with severe sepsis. This study investigated whether various inflammatory mediators, including sTREM-1, could be used as reliable markers to predict the prognosis of patients receiving early goal-directed therapy (EGDT). We prospectively enrolled patients 18 years or older with severe sepsis from April 2009 to May 2010 at a 2,000-bed university hospital. Patients were eligible if the initial resuscitation according to EGDT protocol was immediately performed at the emergency department. Plasma sTREM-1, C-reactive protein, and procalcitonin concentrations were measured on days 0, 3, 7, and 14. Soluble TREM-1 concentrations were significantly higher at admission and pre-EGDT in nonsurvivors (n = 16) than in survivors (n = 47) (514.1 pg/mL [interquartile range, 412.7–1,749.5 pg/mL] vs. 182.4 pg/mL [interquartile range, 54.3–327.0 pg/mL]; P = 0.001). Procalcitonin and C-reactive protein levels did not significantly differ, whereas central venous oxygen saturation and lactate levels at admission were significantly different between the two groups. The only sTREM-1 level remained significantly higher in nonsurvivors until death. On multivariate regression analysis, log(sTREM-1) (P = 0.028), central venous oxygen saturation (P = 0.022), and Simplified Acute Physiology Score II (P = 0.048) values at admission were independently significant. These results suggest that plasma sTREM-1 level at admission could be used as a marker to identify patients with a poor prognosis despite complete initial resuscitation in severe sepsis.

Incidence and risk factors for carbapenem-and multidrug-resistant Acinetobacter baumannii bacteremia in hematopoietic stem cell transplantation recipients

Abstract Background: Bacteremia with multidrug-resistant (MDR) Acinetobacter baumannii with carbapenem resistance is an important healthcare-associated infection that increases morbidity and mortality in immunocompromised patients. The aim of this study was to assess the annual incidence and clinical characteristics of such bacteremia and to identify the risk factors for infection in hematopoietic stem cell transplantation (HSCT) recipients. Methods: A retrospective cohort and case–control study was conducted in 483 HSCT recipients between January 2005 and December 2011 at a single tertiary center. Thirty-eight control HSCT patients without evidence of post-transplant infection were matched with 19 patients with bacteremia due to MDR A. baumannii in a 2:1 ratio. Results: The total incidence of carbapenem-resistant–MDR A. baumannii bacteremia was 0.52 cases/10,000 patient-days. In most cases (17 of 19, 89.5%), bacteremia developed after engraftment. Pneumonia was the origin of bacteremia in all patients. Eighteen (94.7%) patients with bacteremia and 3 (8.3%) without bacteremia died. In multivariate regression analyses, the duration between admission and HSCT (odds ratio (OR) 2.19 per 1-day increase, p = 0.030) and a history of care in an intensive care unit after HSCT (OR 32.2, p = 0.021) were independent risk factors for the development of carbapenem-resistant–MDR A. baumannii bacteremia. Conclusions: We report that carbapenem-resistant–MDR A. baumannii bacteremia in HSCT recipients is a fatal infectious complication and mainly develops after engraftment.

Risk factors for the acquisition of carbapenem-resistant Escherichia coli at a tertiary care center in South Korea: A matched case-control study

BACKGROUND Carbapenem resistance among gram-negative bacilli is an emerging threat worldwide. The objective of this study was to identify risk factors for the acquisition of carbapenem-resistant Escherichia coli (CRE). METHODS We conducted a matched case-control study comprising 57 cases of acquisition of CRE and 114 controls (1:2 matched) selected from patients with a culture of carbapenem-susceptible E coli between January 2006 and December 2010 at a 2000-bed tertiary care center in South Korea. RESULTS On univariate analysis, previous use of carbapenem (P < .01), fluoroquinolone (P < .01), and glycopeptide (P < .01), as well as length of hospital stay (P < .05), were significantly associated with CRE acquisition. On multivariate analysis, previous use of carbapenem (odds ratio [OR], 4.56; 95% confidence interval [CI] 1.44-14.46; P = .01) and previous use of fluoroquinolone (OR, 2.81; 95% CI, 1.14-6.99; P = .03) were independent risk factors. CONCLUSIONS At this institute, the antibiotic selective pressure of carbapenems and fluoroquinolones was shown to be an important risk factor for the acquisition of CRE.

The C-Reactive Protein/Albumin Ratio as an Independent Predictor of Mortality in Patients with Severe Sepsis or Septic Shock Treated with Early Goal-Directed Therapy

Background Sepsis, including severe sepsis and septic shock, is a major cause of morbidity and mortality. Albumin and C-reactive protein (CRP) are considered as good diagnostic markers for sepsis. Thus, initial CRP and albumin levels were combined to ascertain their value as an independent predictor of 180-day mortality in patients with severe sepsis and septic shock. Materials and Methods We conducted a retrospective cohort study involving 670 patients (>18 years old) who were admitted to the emergency department and who had received a standardized resuscitation algorithm (early goal-directed therapy) for severe sepsis and septic shock, from November 2007 to February 2013, at a tertiary hospital in Seoul, Korea. The outcome measured was 180-day all-cause mortality. A multivariate Cox proportional hazard model was used to identify the independent risk factors for mortality. A receiver operating characteristic (ROC) curve analysis was conducted to compare the predictive accuracy of the CRP/albumin ratio at admission. Results The 180-day mortality was 28.35% (190/670). Based on the multivariate Cox proportional hazard analysis, age, the CRP/albumin ratio at admission (adjusted HR 1.06, 95% CI 1.03–1.10, p<0.001), lactate level at admission (adjusted HR 1.10, 95% CI 1.05–1.14, p<0.001), and the Sequential Organ Failure Assessment (SOFA) score at admission (adjusted HR 1.12, 95% CI 1.07–1.18, p<0.001) were independent predictors of 180-day mortality. The area under the curve of CRP alone and the CRP/albumin ratio at admission for 180-day mortality were 0.5620 (P<0.001) and 0.6211 (P<0.001), respectively. Conclusion The CRP/albumin ratio was an independent predictor of mortality in patients with severe sepsis or septic shock.

HIV‐associated neurocognitive disorder in HIV‐infected Koreans: the Korean NeuroAIDS Project

HIV‐associated neurocognitive disorder (HAND) is an independent predictor of early mortality and is associated with many difficulties in activities of daily living. We sought to determine the prevalence of and risk factors for HAND in HIV‐infected Koreans. In addition, we investigated the performance of screening tools and components of neuropsychological (NP) tests for diagnosing HAND.

Diagnostic value of the serum galactomannan assay for invasive aspergillosis: It is less useful in non-haematological patients

Abstract Background: The serum galactomannan assay (GMA) has been widely used for the diagnosis of invasive aspergillosis (IA). GMA is mainly used in patients with haematological malignancies or in those who have undergone haematopoietic stem cell transplantation (HSCT). However, there are few data from non-haematological patients. We evaluated whether GMA is useful for the diagnosis of IA in non-haematological patients.Methods: Patients who were subjected to serum GMA testing from January 2007 to December 2009 were evaluated retrospectively. Patients with haematological diseases or who underwent HSCT were excluded from our analysis. According to the criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group revised in 2008, the patients were categorized as proven, probable, possible, or non-IA. Proven and probable cases were defined as IA in this study.Results: Out of 778 patients, 13 (1.6%) had proven (n =9) or probable (n =4) IA. The sensitivity of the GMA was 23.1% (95% confidence interval (CI) 6.1–54.0%) and the specificity was 76.1% (95% CI 72.9–79.0%). The positive predictive value was 1.6% (95% CI 0.4–5.0%) and the negative predictive value was 98.3% (95% CI 96.8–99.1%). The likelihood ratios of a positive and negative test were 0.96 (95% CI 0.35–2.62) and 1.01 (95% CI 0.75–1.36), respectively.Conclusions: In this study, the sensitivity of the GMA for the diagnosis of IA was very low in non-haematological patients. Although the GMA test is considered useful for the diagnosis of IA in haematological patients, it had low diagnostic value for IA in non-haematological patients.

Relative prevalence and antimicrobial susceptibility of clinical isolates of Elizabethkingia species based on 16S rRNA gene sequencing.

ABSTRACT Some of the previously reported clinical isolates of Elizabethkingia meningoseptica may be later named species of Elizabethkingia. We determined the accuracy of species identification (with two matrix-assisted laser desorption ionization–time of flight mass spectrometry [MALDI-TOF MS] systems and the Vitek 2 GN card), relative prevalence of three Elizabethkingia spp. in clinical specimens, and antimicrobial susceptibility of the species identified by 16S rRNA gene sequencing. Specimens for culture were collected from patients in a university hospital in Seoul, South Korea, between 2009 and 2015. All 3 Elizabethkingia spp. were detected in patients; among the 86 isolates identified by 16S rRNA gene sequencing, 17 (19.8%) were E. meningoseptica, 18 (20.9%) were Elizabethkingiamiricola, and 51 (59.3%) were Elizabethkingiaanophelis. Only the MALDI-TOF Vitek MS system with an amended database correctly identified all of the isolates. The majority (76.7%) of the isolates were from the lower respiratory tract, and 8 (9.3%) were from blood. Over 90% of E. meningoseptica and E. anophelis isolates were susceptible to piperacillin-tazobactam and rifampin. In contrast, all E. miricola isolates were susceptible to fluoroquinolones except ciprofloxacin. Further studies are urgently needed to determine the optimal antimicrobial agents for the treatment of infections due to each individual Elizabethkingia species.

Delta Neutrophil Index as a Prognostic Marker of Early Mortality in Gram Negative Bacteremia

Background Sepsis is a syndrome that results in high morbidity and mortality. We investigated the delta neutrophil index (DN) as a predictive marker of early mortality in patients with gram-negative bacteremia. Materials and Methods We conducted a retrospective study at a tertiary referral hospital in South Korea from November 2010 to March 2011. The DN was measured at onset of bacteremia and 24 hours and 72 hours later. The DN was calculated using an automatic hematology analyzer. Factors associated with 10-day mortality were assessed using logistic regression. Results A total of 172 patients with gram-negative bacteremia were included in the analysis; of these, 17 patients died within 10 days of bacteremia onset. In multivariate analysis, Sequental organ failure assessment scores (odds ratio [OR]: 2.24, 95% confidence interval [CI]: 1.31 to 3.84; P = 0.003), DN-day 1 ≥ 7.6% (OR: 305.18, 95% CI: 1.73 to 53983.52; P = 0.030) and DN-day 3 ≥ DN-day 1 (OR: 77.77, 95% CI: 1.90 to 3188.05; P = 0.022) were independent factors associated with early mortality in gram-negative bacteremia. Of four multivariate models developed and tested using various factors, the model using both DN-day 1 ≥ 7.6% and DN-day 3 ≥ DN-day 1 was most predictive early mortality. Conclusions DN may be a useful marker of early mortality in patients with gram-negative bacteremia. We found both DN-day 1 and DN trend to be significantly associated with early mortality.

Predictive factors for indeterminate result on the QuantiFERON test in an intermediate tuberculosis-burden country

OBJECTIVES The QuantiFERON-TB Gold In-Tube (QFT-G IT) test is based on the cellular immune response, and this assay can result in indeterminate results for the diagnosis of tuberculosis. The occurrence of indeterminate results may decrease the clinical usefulness of this test. Therefore, we investigated possible predictive factors that can influence the occurrence of indeterminate results from the QFT-G IT test. METHODS We conducted a case-control study with 162 case patients who had indeterminate results from a QFT-G IT test at a tertiary hospital in South Korea, from September 2006 to September 2009. RESULTS Of the 1276 patients, 162 (12.7%) cases that underwent QFT-G IT testing were reported as indeterminate results. Severe lymphopenia (odds ratio [OR] = 8.839; p < 0.001), chronic renal disease (OR = 2.838; p = 0.007), autoimmune disease (OR = 2.527; p = 0.017) and chronic lung disease (OR = 3.169; p = 0.007) were independent predictive factors for indeterminate results from a QFT-G IT test. CONCLUSION The patients with lower lymphocyte counts or immunosuppressive conditions showed a higher probability of indeterminate results from the QFT-G IT test. Careful attention to the pre-analytical conditions may be able to minimize this proportion.