Youn Jeong Kim

Epidemiology and risk factors for bacteremia in 144 consecutive living-donor liver transplant recipients.

Purpose Bacteremia is a major infectious complication associated with mortality in liver transplant recipients. The causative organisms and clinical courses differ between medical centers due to variations in regional bacterial epidemiology and posttransplant care. Further, living donors in Korea contribute to 83% of liver transplants, and individualized data are required to improve survival rates. Patients and Methods We retrospectively analyzed 104 subjects who had undergone living-donor liver transplant from 2005 to 2007. Results Among the 144 consecutive living-donor liver transplant recipients, 24% (34/144) developed bacteremia, 32% (46/144) developed non-bacteremic infections, and 44% (64/144) did not develop any infectious complications. Forty episodes of bacteremia occurred in 34 recipients. The major sources of bacteremia were intravascular catheter (30%; 12/40), biliary tract (30%; 12/40), and abdomen (22.5%; 9/40). Gram-positive cocci were more common (57.5%; 23/40) than Gram-negative rods (32.5 %; 13/40) and fungi (10%; 4/40). The data revealed that the following factors were significantly different between the bacteremia, non-bacteremic infection, and no infection groups: age (p = 0.024), posttransplant hemodialysis (p = 0.002), ICU stay (p = 0.012), posttransplant hospitalization (p < 0.0001), and duration of catheterization (p < 0.0001). The risk factors for bacteremia were older than 55 years (odds ratio, 6.1; p = 0.003), catheterization for more than 22 days (odds ratio, 4.0; p = 0.009), UNOS class IIA (odds ratio, 6.6; p = 0.039), and posttransplant hemodialysis (odds ratio, 23.1; p = 0.001). One-year survival rates in the bacteremic, non-bacteremic infection, and no infection groups were 73.2%, 91.3%, and 93.5%, respectively. Conclusion Early catheter removal and preservation of renal function should focus for improving survival after transplant.

Risk Factors for Mortality in Patients with Carbapenem-Resistant Acinetobacter baumannii Bacteremia: Impact of Appropriate Antimicrobial Therapy

This study investigated predictors associated with 14-day mortality, and focused especially on the impact of appropriate antimicrobial treatment among patients with carbapenem-resistant Acinetobacter baumannii (CRAB) bacteremia. This retrospective study was performed at a tertiary care hospital in Korea from June 2007 to June 2010. Antibiotic therapy was considered appropriate if the antibiotics were administered via an appropriate route within 24 hr after the result of blood culture, had in vitro sensitivity to isolated strains, and of an adequate dosage according to the current guidelines. Ninety-five patients with A. baumannii bacteremia were included; of these, 53 (55.8%) were infected with CRAB. The overall infection-related 14-day mortality was higher in patients receiving inappropriate antimicrobial therapy than in patients receiving appropriate therapy (59.5% [22/37] vs 13.8% [8/58], P < 0.05). Multivariate analysis showed that septic shock (OR 10.5, 95% CI, 1.93-57.4; P = 0.006), carbapenem-resistance (OR 7.29, 95% CI 1.57-33.8; P = 0.01), pneumonia as a source of bacteremia (OR 5.29, 95% CI 1.07-26.1; P = 0.04), and inappropriate antimicrobial therapy (OR 8.05, 95% CI 1.65-39.2; P = 0.009) were independent risk factors for 14-day mortality. Early definite antimicrobial therapy had an influence on favorable outcomes in patients with A. baumannii bacteremia.

Risk factors for mortality in patients with Pseudomonas aeruginosa bacteremia; retrospective study of impact of combination antimicrobial therapy

BackgroundWhether the combination of antimicrobial therapy is a factor in mortality in Pseudomonas aeruginosa bacteremia remains to be elucidated. This study investigated the risk factors for mortality in P. aeruginosa bacteremia patients and the influence of adequate antimicrobial therapy and combination therapy on clinical outcomes.MethodsThis retrospective study analyzed data of 234 patients with P. aeruginosa bacteremia at a 1,200-bed tertiary teaching university hospital in South Korea between January 2010 and December 2012. Factors associated with mortality were determined. Mortality was compared in patients with adequate empirical and targeted combination therapy, and monotherapy, and inappropriate therapy.ResultsA total of 141 (60.3%) patients were given appropriate empirical antibiotic treatment (combination therapy in 38 and monotherapy in 103). Among 183 patients (78.2%) who finally received appropriate targeted treatment, 42 had combination therapy and 141 had monotherapy. The percentage of patients receiving empirical combination therapy was slightly, but not significantly higher, in the survivor group than in the nonsurvivor group (17.0% [31/182] vs. 13.5% [7/52], p = 0.74). A similar tendency was demonstrated for targeted combination therapy (19.8% [36/182] vs. 11.5% [6/52], respectively; p = 0.31). However, in a subgroup analysis of data from patients (n = 54) with an absolute neutrophil count less than 500/mm3, the patients who had appropriate empirical or targeted combination therapy showed better outcomes than those who underwent monotherapy or inappropriate therapy (p < 0.05). Mechanical ventilation (odds ratio [OR], 6.93; 95% confidence interval [CI], 2.64–18.11; p = 0.0001), the use of a central venous catheter (OR, 2.95; 95% CI, 1.35–6.43; p = 0.007), a high Acute Physiology and Chronic Health Evaluation II score (OR, 4.65; 95% CI, 1.95–11.04; p = 0.0001), and presence of septic shock (OR, 2.91; 95% CI, 1.33–6.38; p = 0.007) were independent risk factors for 14-day mortality.ConclusionsDisease severity was a critical factor for mortality in our patients with P. aeruginosa bacteremia. Overall, combination therapy had no significant effect on 14-day mortality compared with monotherapy. However, appropriate combination therapy showed a favorable effect on survival in patients with febrile neutropenia.

Risk factors for vancomycin-resistant enterococci infection and mortality in colonized patients on intensive care unit admission

This study examined the incidence of and risk factors for development of vancomycin-resistant enterococci (VRE) infection and death in VRE-colonized patients in a medical intensive care unit. VRE colonization was identified in 184 patients (17.6%) in whom VRE perianal swab cultures were obtained. Of these, 28 (11.9%) developed VRE infection. Control of infectious sources is crucial to decrease development of VRE infections and optimize the survival of VRE-colonized patients.

Liver abscess due to Klebsiella pneumoniae: Risk factors for metastatic infection

Abstract Introduction: Klebsiella pneumoniae-associated liver abscess (KPLA) is often accompanied by extrahepatic complications. We investigated the clinical features and outcomes of patients with and without metastatic infections and compared the 2 groups. Methods: We retrospectively reviewed the medical records of 161 patients with KPLA who were admitted to 2 tertiary referral hospitals in Korea. Results: In total, 9.9% had a metastatic infection. The most commonly involved distant sites were the eyes (n = 7) and the lungs (n = 6). In multivariate analysis, diabetes mellitus as an underlying disease (odds ratio (OR) 2.30, 95% confidence interval (CI) 1.05–9.51; p = 0.03) and a platelet count < 80,000/mm3 (OR 11.60, 95% CI 2.53–53.26; p = 0.002) were associated with metastatic infection. Extended-spectrum beta-lactamase (ESBL) production was not observed in K. pneumoniae from patients with metastatic infection, whereas 3.4% of the bacteria in patients without metastatic infection had ESBL production. However, this difference was not statistically significant (p = 0.45). The in-hospital mortality rate was not significantly different (0% vs. 2.8%; p = 0.52). By multivariate analysis, the Acute Physiology and Chronic Health Evaluation II (APACHE II) score was independently associated with mortality among patients with KPLA (OR 1.5, 95% CI 1.12–2.00; p = 0.006). Conclusions: Clinicians must be aware of potential metastatic infections in patients with KPLA, especially if they have diabetes mellitus and thrombocytopenia. The APACHE II score was predictive of mortality in patients with KPLA.

Trend of CD4+ Cell Counts at Diagnosis and Initiation of Highly Active Antiretroviral Therapy (HAART): Korea HIV/AIDS Cohort Study, 1992-2015

Background CD4+ cell counts reflect immunologic status of human immunodeficiency virus (HIV) patients. Recommended CD4+ cell counts for the initiation of highly active antiretroviral therapy (HAART) has increased over the past several years in various HIV treatment guidelines. We investigated the trend of CD4+ cell counts at diagnosis and treatment start using data from the Korea HIV/acquired immune deficiency syndrome (AIDS) Cohort Study. Materials and Methods The Korea HIV/AIDS Cohort Study started in 2006 and enrolled HIV patients from 21 tertiary and secondary hospitals in South Korea. The data for CD4+ cell counts at diagnosis and HAART initiation from these HIV patients were analyzed by three-year time intervals and presented by number of CD4+ cells (≤100, 101-200, 201-350, 351-500 and >500 cells/mm3). The HIV-RNA titer at diagnosis and HAART initiation were presented by 3-year intervals by groups ≤50,000, 50,001-100,000, 100,001-200,000, 200,001-1,000,000, and >1,000,000 copies/mL. Results Median values of CD4+ cell count and HIV-RNA titer at initial HIV diagnosis were 247 cells/mm3 and 394,955 copies/mL, respectively. At time of initiating HAART, median values of CD4+ cell count and HIV-RNA were 181 cells/mm3 and 83,500 copies/mL, respectively. Patients with low CD4+ cell count (CD4+ cell count ≤200 cells/mm3) at diagnosis (31-51%) and initiation of HAART accounted for the largest proportion (30-65%) over the three-year time intervals. This proportion increased until 2010-2012. Conclusion CD4+ cell count at initiation of HAART was found to be very low, and the increase in late initiation of HAART in recent years is of concern. We think that this increase is primarily due to an increasing proportion of late presenters. We recommend early detection of HIV patients and earlier start of HAART in order to treat and prevent spread of HIV infection.

A Case-Control Study to Identify Risk Factors for Totally Implantable Central Venous Port-Related Bloodstream Infection

Purpose To date, the risk factors for central venous port-related bloodstream infection (CVPBSI) in solid cancer patients have not been fully elucidated. We conducted this study in order to determine the risk factors for CVP-BSI in patients with solid cancer. Materials and Methods A total of 1,642 patients with solid cancer received an implantable central venous port for delivery of chemotherapy between October 2008 and December 2011 in a single center. CVP-BSI was diagnosed in 66 patients (4%). We selected a control group of 130 patients, who were individually matched with respect to age, sex, and catheter insertion time. Results CVP-BSI occurred most frequently between September and November (37.9%). The most common pathogen was gram-positive cocci (n=35, 53.0%), followed by fungus (n=14, 21.2%). Multivariate analysis identified monthly catheter-stay as a risk factor for CVP-BSI (p=0.000), however, its risk was lower in primary gastrointestinal cancer than in other cancer (p=0.002). Initial metastatic disease and long catheter-stay were statistically significant factors affecting catheter life span (p=0.005 and p=0.000). Results of multivariate analysis showed that recent transfusion was a risk factor for mortality in patients with CVP-BSI (p=0.047). Conclusion In analysis of the results with respect to risk factors, prolonged catheter-stay should be avoided as much as possible. It is necessary to be cautious of CVP-BSI in metastatic solid cancer, especially non-gastrointestinal cancer. In addition, avoidance of unnecessary transfusion is essential in order to reduce the mortality of CVP-BSI. Finally, considering the fact that confounding factors may have affected the results, conduct of a well-designed prospective controlled study is warranted.

Etiology and outcome of iliopsoas muscle abscess in Korea; changes over a decade

OBJECTIVES Iliopsoas muscle abscess (IPA) is considered a rare disease whose etiology has changed depending on the country and antibiotic selection pressure. This study evaluates the changes in etiology, clinical outcome, and risk factors for mortality for IPA. METHODS We reviewed the medical records of a total of 116 patients with IPA who were admitted to 4 university hospitals in Korea over the 11 years, and compared the etiology between 2001-2006 (period 1, n=44) and 2007-2012 (period 2, n=72). RESULTS Among 75 cases with a definitive microbial diagnosis, the predominant etiological organisms were S.aureus(45.3%), followed by M. tuberculosis(14.7%) and K.pneumoniae(9.3%). The percentage of MRSA in period 2 increased remarkably compared to period 1, from 25 % to 44.4%, and incidence of M.tuberculosis from 7.1% to 19.1, although these were not statistically significant. The overall mortality was 6.8% in period 1, and 13.9% in period 2, and sepsis as an initial manifestation (OR 293.5, CI 7.1 - 12034.4, P=0.003) and serum creatinine level (OR 0.43, CI 0.23 - 0.80, P=0.008) were independent predictors of mortality. Invasive procedure improved the prognosis in cases with microbiologic confirmed pyogenic psoas abscess (46/50 [92%] vs. 9/14 [64.3%], p=0.008). CONCLUSION The incidence of MRSA as a cause of IPA is on the increase. Although the overall prevalence of tuberculosis is decreasing, tuberculosis is still an important cause of IPA. Initial clinical status and invasive intervention can lead to favorable outcomes.

Clinical impact of body mass index on bactibilia and bacteremia.

BackgroundThe aim of this study was to evaluate the association between obesity and infected bile or bacteremia in patients with acute calculous cholecystitis.MethodsAuthors analyzed the medical records of 139 patients who had undergone cholecystectomy for the treatment of acute calculous cholecystitis from January 2007 to June 2013 in a single teaching hospital. Association of body mass index (BMI) with bactibilia and bacteremia was assessed using univariate and multivariate analysis. Clinical findings and biliary infection related data were recorded for the following variables: gender, age, alcohol and smoking history, the results of blood and bile cultures, cholesterolosis, diabetes, hypertension, and duration of the hospital stay.ResultsThe microbial culture rate of bactibilia and bacteremia were 50.4% and 21.6%, respectively. In the univariate analysis, bacteremia was associated with bactibilia (OR: 4.33, p = 0.002). In the multivariate analysis for the risk factors of bactibilia, BMI and bacteremia were related with bactibilia (OR: 0.59, 95% CI: 0.42-0.84, p = 0.003) (OR: 3.32, 95% CI: 1.22-9, p = 0.02). In the multivariate analysis for the risk factors of bacteremia, BMI, bactibilia and age were related with bacteremia (OR: 0.76, 95% CI: 0.59-0.99, p = 0.04) (OR: 3.46, 95% CI: 1.27-9.45, p = 0.02) (OR: 1.05, 95% CI: 1.01-1.09, p = 0.02).ConclusionIn this retrospective study, BMI was inversely correlated with bacteremia or bactibilia, which means obese or overweight patients are less likely to be associated with bacteremia or bactibilia in patients with acute calculous cholecystitis.

Two cases of scrub typhus presenting with Guillain-Barre syndrome with respiratory failure.

To the Editor, Scrub typhus is an acute febrile disease caused by Rickettsia, and traditionally occurs in autumn. Orientia tsutsugamushi is an obligate intracellular Gram-negative bacterium that proliferates in vascular endothelial cells; this characteristic enables the involvement of multiple organs. The most common clinical features are conjunctival injection, high fever, and lymphadenopathy. Neurological complications, such as meningitis and hearing impairment with suspected cranial nerve (VIII) invasion, were reported in 12.5% cases [1,2]. However, involvement of brain parenchyma or peripheral nerves is rare. Only three cases of Guillain-Barre syndrome (GBS) related to scrub typhus have been reported [3-5]. We experienced two cases of scrub typhus-related GBS that presented with severe respiratory failure and were managed with mechanical ventilation, doxycycline, and immunoglobulin. A 60 year-old male visited the emergency department after suffering weakness of the lower extremities for two days. Ten days before the visit, he had visited a local private clinic for headache and chills. After being diagnosed with scrub typhus, he was treated with doxycycline. His symptoms marginally improved, but weakness in both lower extremities developed. He had no other medical history except pulmonary tuberculosis 10 years previously. Vital signs were stable (blood pressure 120/70 mmHg, pulse rate 68/min, body temperature 36.6℃). A physical examination revealed lymphadenopathy in the right inguinal area, a maculopapular rash on the chest wall, and eschar on the right knee. He showed an alert mental status, and a manual muscle test (MMT) revealed lower extremity weakness (upper extremity, grade V; lower extremity, grade IV). Laboratory results showed a WBC count of 9,020/mm3 (neutrophils 51.9%, lymphocytes 35.7%); hemoglobin (Hb), 12.2 g/dL; platelets, 269,000/mm3; alanine aminotransferase (AST), 100 IU/L; alanine aminotransferase (ALT), 110 IU/L; blood urea nitrogen (BUN), 10 mg/dL; creatinine, 0.52 mg/dL; total protein, 6.5 mg/dL; albumin, 3.3 mg/dL; and C-reactive protein, 2.10 mg/dL. Lumbar puncture revealed a glucose level of 74 mg/dL, a total protein level 210 mg/dL, and white blood cell (WBC) count of 20/mm3 (lymphocytes 90%). Serum O. tsutsugamushi antibody titer was positive (1:320). There was no serologic evidence of Epstein-Barr virus (EBV) or cytomegalovirus (CMV) infection or reactivation (VCA-IgG/IgM +/-, EADR-IgG -/±, EBNA IgG +/-, CMV IgG/IgM +/-). A human immunodeficiency virus (HIV) test was negative. Two days after admission, weakness in both extremities progressed (upper, grade II; lower, grade II), and he developed a mild disturbance of consciousness. Serum anti-ganglioside antibodies, GD1b IgG and GM1 IgG, and anti-myelin-associated glycoprotein antibody were negative, but GM1 IgM and GD1b IgM antibodies were positive (Table 1). An electromyography showed diffuse demyelinated neuropathy, which was prominent in the lower extremities. The brain magnetic resonance diffusion image was normal. Intravenous immunoglobulins were administered for five days (22 g, 400 mg/kg/day), and doxycycline was maintained at 100 mg/12 hr (PO). On day 4 after admission, the patient complained of dysphagia and dyspnea. The patient required mechanical ventilation due to respiratory muscle weakness. Eleven days after admission, he recovered spontaneous breathing, and the ventilator was removed. At 48 days after admission, his MMT grade recovered to normal, and he was discharged without complications. Table 1 Comparison of clinical characteristics In the second case, a 46 year-old female without any prior medical history, presented at an emergency department having suffered decreased mental status for 12 hours. Before admission, she had visited the local clinic complaining of fever and myalgia for the previous seven days. After diagnosis with type II diabetes mellitus and ketoacidosis, intravenous fluid replacement and glycemic control were initiated. During management of ketoacidosis, an unexplained decrease in mental status and hypoxemia were noticed. After intubation, she was transferred to our hospital. Initial vital signs were unstable (blood pressure 70/50 mmHg, pulse rate 127/min, respiration 12 times/min, and body temperature 38.6℃). Chest examination revealed rale sounds in the lower right lung field. A maculopapular rash on the entire body and eschar on the posterior site of the left knee were also noticed. MMT revealed weakness in both extremities (upper, grade III; lower, grade III). Laboratory results showed a WBC count of 12,560/mm3 (neutrophils, 77%; lymphocytes, 17%); Hb, 14 g/dL; platelets, 144,000/mm3; AST, 40 IU/L; ALT, 29 IU/L; BUN, 45.1 mg/dL; creatinine, 1.06 mg/dL; total protein, 5.5 mg/dL; albumin, 2.3 mg/dL; and C-reactive protein, 3.17 mg/dL. Sodium, potassium, chloride, and glucose levels of 150 mEq/L, 3.8 mEq/L, 116 mEq/L, and 196 mg/dL, respectively, were also detected. HbA1C was 12.3%, and D-dimer, fibrin degradation product, and fibrinogen were 14 mg/mL, 52 mg/mL, and 137 g/L, respectively. An arterial blood gas test before intubation showed metabolic acidosis and hypoxemia (pH 7.122; PCO2, 58.0 mmHg; PaO2, 53.1 mmHg; HCO3-, 15.3 mmol/L; SpO2, 75.6%). Chest X-ray revealed ground glass opacity on both the lower lung fields. Serum O. tsutsugamushi antibody titer was positive at 1:320. There was no serologic evidence of EBV and CMV infection or reactivation, and an HIV test was negative. Bacterial growth was not detected on blood, urine, and sputum cultures. Serum Mycoplasma pneumoniae IgM and IgG, and Streptococcus pneumoniae and Legionella urinary antigens were also negative. Due to the diagnosis of diabetic ketoacidosis, nosocomial pneumonia, and septic shock with pulmonary edema, empirical antibiotics were administered (meropenem 1 g/8 hr, teicoplanin 400 mg/24 hr). Intravenous insulin injection and doxycycline 100 mg/12 hr (PO) were maintained for seven days. Five days after admission, her vital signs were stable, and her mental status was alert. Although her chest X-ray markedly improved after 13 days, muscle weakness in the extremities (upper, grade IV; lower, grade III) remained, and a low respiration rate (7-8/min) was detected. A brain computed tomography scan was normal, and electromyography showed acute sensoriomotor polyneuropathy, which may have been due to GBS. Spinal tapping revealed a WBC count of 1/m3; RBC, 0/mm3; protein, 118 mg/dL; and glucose, 64 mg/dL. Serum anti-ganglioside antibodies GD1b IgG/IgM and GM1 IgG/IgM and anti-myelin-associated glycoprotein antibody were all negative (Table 1). After recovery from intubation, rehabilitation maintenance was required. Two months after admission, MMT revealed normal muscle power, and she was discharged without complications. GBS is known to be associated with several infections, such as Campylobacter jejuni, CMV, EBV, and M. pneumoniae. Our first case was diagnosed as scrub typhus based on maculopapular rash, eschar, and an O. tsutsugamushi antibody test. Additionally, we could diagnose GBS based on neurological examination, electromyography, and the presence of anti-ganglioside antibodies. We excluded EBV, CMV, Mycoplasma, and other bacteria. Involvement of the respiratory system is observed in 10-30% GBS patients [3]; however, there is no evidence of respiratory failure requiring mechanical ventilation among the reported cases of scrub typhus-related GBS [3-5]. Typical electromyography findings of demyelinated neuropathy and lower extremity weakness were detected, and GD1b and GM1 IgM antibody results were also positive. A positive result for the anti-ganglioside antibody had not been observed in the reported cases [3-5]. GBS mortality rates are usually 3-7%, but mortality in patients requiring respiratory support can be as high as 20% [2]. Our cases required mechanical ventilation, but both recovered completely. The second case was combined with pneumonia, diabetic ketoacidosis, and scrub typhus, and was treated with a broad spectrum of empirical antibiotics and fluid replacement. After laboratory and radiologic findings improved, ongoing dyspnea, progressive respiratory failure, and extremity weakness were observed. We diagnosed GBS based on neurological examination and electromyography, and excluded other GBS-related infections, such as CMV, EBV, and other bacteria. Mimicry involves the sharing of antigens between the host and an infecting microorganism, and is a type of cross-reactivity similar to an autoimmune disease. It is enabled by the activation of receptors on B- or T-lymphocytes by both the host and microorganism [5]. Scrub typhusrelated GBS is suspected to undergo a similar phenomenon. Gangliosides are important glycolipids associated with cell growth and signal transduction, and more than 100 subtypes exist [1]. O. tsutsugamushi antibody or antigens presented on infected cells are suspected to activate mimicry on myelin cells or peripheral nerve axons, which elicits immune reactions similar to autoimmune diseases. A positive result for the anti-ganglioside antibodies GD1b and GM1 IgM supports the conclusion that mimicry between pathogenic antigens and the myelin of peripheral nerves caused the immune reaction and GBS.