A comparison of the clinical characteristics of elderly and non-elderly women with community-onset, non-obstructive acute pyelonephritis

BACKGROUND/AIMS

Acute pyelonephritis (APN) is the most common cause of community-onset bacteremia in hospitalized elderly patients. The objectives of this study were to investigate the differences in the clinical and microbiological data of hospitalized elderly and non-elderly women with community-onset APN.

METHODS

Women with community-onset APN as a discharge diagnosis were identified from January 2004 to December 2013 using an electronic medical records system. We compared the clinical and microbiologic data in elderly and non-elderly women with community-onset APN due to Enterobacteriaceae.

RESULTS

Of the 1,134 women with community-onset APN caused by Enterobacteriaceae, 443 were elderly and 691 were non-elderly women. The elderly group had a lower frequency of upper and lower urinary tract symptoms/signs than the non-elderly. The incidence of bacteremia, extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, patients with a C-reactive protein (CRP) level ≥ 15 mg/dL, and patients with a leukocyte count ≥ 15,000/mm(3) in the blood, were significantly higher in the elderly group than in the non-elderly group. The proportion of patients requiring hospitalization for 10 days or more was significantly higher in the elderly group compared to the non-elderly group (51.5% vs. 26.2%, p < 0.001). The clinical cure rates at 4 to 14 days after the end of therapy were 98.3% (338/344) and 97.4% (519/533) in the elderly and non-elderly groups, respectively (p = 0.393).

CONCLUSIONS

Elderly women with APN exhibit higher serum CRP levels, a higher frequency of bacteremia, a higher proportion of ESBL-producing uropathogens, and require a longer hospitalization than non-elderly women, although these patients may not complain of typical urinary symptoms.

Phase IV: randomized controlled trial to evaluate lot consistency of trivalent split influenza vaccines in healthy adults

Influenza vaccines are the primary method for preventing influenza and its complications. Considering the increasing demand for influenza vaccines, vaccine manufacturers are required to establish large-scale production systems. This phase IV randomized trial was conducted to evaluate the lot consistency of trivalent split influenza vaccines regarding immunogenicity and safety. A total of 1,023 healthy adults aged 18-64 y were enrolled in the study. Subjects were randomly assigned in a 1:1 ratio to receive the GC FLU® Prefilled Syringe or the GC FLU® Injection, and they were further randomized to one of 3 lots of each vaccine in a 1:1:1 ratio. In both GC FLU® Injection and GC FLU® Prefilled Syringe groups, immune responses were equivalent between lots for each of the 3 vaccine strains on day 21. The 2-sided 95% CI of GMT ratios between pairs of lots were between 0.67 and 1.5, meeting the equivalence criteria. After vaccination, all 3 criteria of the European Medicines Agency were met in both GC FLU® Injection and GC FLU® Prefilled Syringe groups. The vaccines showed tolerable safety profiles without serious adverse events. The demonstration of lot consistency, robust immunogenic responses and favorable safety profiles support the reliability of mass-manufacturing systems for the GC FLU® Injection and GC FLU® Prefilled Syringe.

Spontaneous Pneumomediastinum, Pneumopericardium, and Pneumothorax with Respiratory Failure in a Patient with AIDS and Pneumocystis jirovecii Pneumonia

Spontaneous pneumothorax occurs in up to 35% of patients with Pneumocystis jirovecii pneumonia. However, spontaneous pneumomediastinum and pneumopericardium are uncommon complications in patients infected with human immunodeficiency virus, with no reported incidence rates, even among patients with acquired immunodeficiency syndrome (AIDS) and P. jirovecii pneumonia. We report a case of spontaneous pneumomediastinum, pneumopericardium, and pneumothorax with respiratory failure during treatment of P. jirovecii pneumonia in a patient with AIDS; the P. jirovecii infection was confirmed by performing methenamine silver staining of bronchoalveolar lavage specimens. This case suggests that spontaneous pneumomediastinum and pneumopericardium should be considered in patients with AIDS and P. jirovecii pneumonia.

Susceptibility of Escherichia coli from community-acquired urinary tract infection to fosfomycin, nitrofurantoin, and temocillin in Korea

With increase of multi-drug resistant Escherichia coli in community-acquired urinary tract infections (CA-UTI), other treatment option with a therapeutic efficacy and a low antibiotic selective pressure is necessary. In this study, we evaluated in vitro susceptibility of E. coli isolates from CA-UTI to fosfomycin (FM), nitrofurantoin (NI), temocillin (TMO) as well as trimethoprim-sulfamethoxazole (SMX), ciprofloxacin (CIP) and cefepime (FEP). The minimal inhibitory concentrations were determined by E-test or agar dilution method according to the Clinical and Laboratory Standards Institute guidelines, using 346 E. coli collected in 12 Korean hospitals from March 2010 to February 2011. FM, NI and TMO showed an excellent susceptibility profile; FM 100% (346/346), TMO 96.8% (335/346), and NI 99.4% (344/346). Conversely, resistance rates of CIP and SMX were 22% (76/346) and 29.2% (101/349), respectively. FEP still retained an activity of 98.5%. In Korea, NI and TMO in addition to FM are a good therapeutic option for uncomplicated CA-UTI, especially for lower UTI.

Comparison of the clinical characteristics of diabetic and non-diabetic women with community-acquired acute pyelonephritis: a multicenter study

OBJECTIVES

Purpose of this study was to compare clinical characteristics and treatment outcomes in diabetic and non-diabetic women with community-acquired APN (CA-APN).

METHODS

We prospectively collected and analyzed clinical data of women with CA-APN who attended 11 hospitals in South Korea from March 2010 to February 2012.

RESULTS

Of a total of 775 patients, 246 (31.7%) were diabetic and 529 (68.3%) non-diabetic. Fewer of the diabetic patients had flank pain (27.6% vs. 37.2% P = 0.009), symptoms of lower urinary tract infection (57.3% vs. 69.6% P = 0.001) and costovertebral angle tenderness (54.9% vs. 72.2% P < 0.001). However, more of them had C-reactive protein ≥20 mg/dL (40.7% vs. 27.4% P < 0.001), azotemia (29.3% vs. 13.4% P < 0.001) and bacteremia (53.7% vs. 38.2% P < 0.001). Final clinical failure rates and deaths did not differ between the two groups: 6.9% vs. 4.5%, P = 0.169; 2.0% vs. 1.7%, P = 0.747. However, hospitalization was longer in the diabetics than the non-diabetics (median 9.0 days vs. 7.0 days, P < 0.001). In logistic regression, diabetes was independently associated with longer hospitalization (OR 1.7, CI 1.1-2.7, P = 0.011), together with nausea/vomiting, history of admission within 1 year, bacteremia, azotemia, and dementia, as well as extended-spectrum β-lactamase (ESBL)-positivity and fluoroquinolone resistance of uropathogens.

CONCLUSIONS

CA-APN patients with diabetes have more severe disease manifestations and require longer hospitalization than non-diabetic patients although their clinical findings are less clear than those of non-diabetic patients.

Age- and influenza activity-stratified case definitions of influenza-like illness: experience from hospital-based influenza surveillance in South Korea

OBJECTIVES

This study aims to identify clinical case definitions of influenza with higher accuracy in patients stratified by age group and influenza activity using hospital-based surveillance system.

METHODS

In seven tertiary hospitals across South Korea during 2011-2012 influenza season, respiratory specimens were obtained from patients presenting an influenza-like illness (ILI), defined as having fever plus at least one of following symptoms: cough, sore throat or rhinorrhea. Influenza was confirmed by reverse transcriptase-polymerase chain reaction. We performed multivariate logistic regression analyses to identify clinical variables with better relation with laboratory-confirmed influenza, and compared the accuracy of combinations.

RESULTS

Over the study period, we enrolled 1417 patients, of which 647 had laboratory-confirmed influenza. Patients with cough, rhinorrhea, sore throat or headache were more likely to have influenza (p<0.05). The most accurate criterion across the study population was the combination of cough, rhinorrhea, sore throat and headache (sensitivity 71.3%, specificity 60.1% and AUROC 0.66). The combination of rhinorrhea, sore throat and sputum during the peak influenza activity period in the young age group showed higher accuracy than that using the whole population (sensitivity 89.3%, specificity 72.1%, and AUROC 0.81).

CONCLUSIONS

The accuracy of clinical case definitions of influenza differed across age groups and influenza activity periods. Categorizing the entire population into subgroups would improve the detection of influenza patients in the hospital-based surveillance system.

Clinical courses and outcomes of hospitalized adult patients with seasonal influenza in Korea, 2011-2012: Hospital-based Influenza Morbidity & Mortality (HIMM) surveillance

Influenza is an acute respiratory illness, which can be accompanied by complications such as pneumonia. This study was conducted to survey the clinical courses and outcomes of hospitalized adult patients with laboratory-confirmed seasonal influenza. A prospective case-control study was performed in adult influenza patients who were admitted to hospitals participating in the Hospital-based Influenza Morbidity and Mortality (HIMM) surveillance system in Korea from October 2011 to May 2012. Cases with complicated influenza were compared to those without complications. A total of 123 (5.6%) patients among 2184 laboratory-confirmed adult influenza patients were hospitalized during the 2011-2012 influenza epidemic season. Forty (32.5%) experienced 50 complication episodes. Age older than 60 years (P < 0.01), male sex (P = 0.04), diabetes (P < 0.01), chronic cardiovascular disease (P < 0.01) and neuromuscular disease (P = 0.02) were significantly related to development of complications in univariate analysis. Multivariate logistic regression analysis revealed that diabetes (odds ratio [OR] 3.63, 95% confidence interval [CI] 1.15-11.51, P = 0.02) was an independent risk factor for complicated seasonal influenza. C-reactive protein (CRP) was discriminative between complicated and uncomplicated influenza (cutoff value 13 mg/L, sensitivity 70%, specificity 74%). Complicated patients received antibiotics more frequently (P < 0.01) with longer hospital stays (P = 0.01). In conclusion, diabetic patients are at great risk for complicated influenza, and CRP would be useful to predicting complication. Therefore, early interventions such as antiviral therapy should be considered for high risk patients with diabetes, especially those with increased serum CRP level.

Hospital-based influenza morbidity and mortality surveillance system for influenza-like illnesses: a comparison with national influenza surveillance systems

The Hospital-based Influenza Morbidity and Mortality (HIMM) surveillance system is an emergency room (ER)-based influenza surveillance system in Korea that was established in 2011. The system was established under the assumption that integrated clinical and virologic surveillance could be performed rapidly and easily at seven tertiary hospitals' ER. Here, we assessed the correlation between data generated from the HIMM surveillance system and the Korean national influenza surveillance systems during the 2011-2012 influenza season using cross-correlation analysis and found strong correlations. Rapid antigen-test-based HIMM surveillance would predict the start of influenza epidemic earlier than pre-existing influenza-like-illness-based surveillance.

Hospital-based influenza surveillance in Korea: hospital-based influenza morbidity and mortality study group

Influenza epidemics occur annually with variations in size and severity. Hospital-based Influenza Morbidity & Mortality was established to monitor influenza epidemics and their severity, which is composed of two surveillance systems: emergency room-based and inpatient-based surveillance. Regarding emergency room-based surveillance, influenza-like illness index (influenza-like illness cases per 1,000 emergency room-visiting subjects), number of laboratory-confirmed cases and the distribution of influenza types were estimated weekly. Inpatient-based surveillance included monitoring for hospitalization, complications, and mortality. The emergency room influenza-like illness index correlated well with the number of laboratory-confirmed influenza cases, and showed a bimodal peak at Week 4 (179.2/1,000 emergency room visits) and Weeks 13-14 (169.6/1,000 emergency room visits) of 2012. Influenza A was the predominant strain during the first epidemic peak, while influenza B was isolated exclusively during the second peak. In 2011-2012 season, the mean admission rate of emergency room-visiting patients with influenza-like illness was 16.3% without any increase over the epidemic period. Among the hospitalized patients with influenza, 33.6% (41 out of 122 patients) were accompanied by complications, and pneumonia (28.7%, 35 out of 122 patients) was the most common. Most fatal cases were caused by influenza A (96.2%) after the first epidemic peak. In conclusion, Hospital-based Influenza Morbidity & Mortality was effective for monitoring the trends in circulating influenza activity concurrently with its severity. In the 2011-2012 season, the influenza epidemic persisted for a ≥ 5-month period, with a bimodal peak of influenza A and B in sequence. Overall, influenza A was more severe than influenza B.

HIV downregulates interferon-stimulated genes in primary macrophages

HIV is able to outpace the innate immune response, including that mediated by interferon (IFN), to establish a productive infection. Primary macrophages, however, may be protected from HIV infection by treatment with type I IFN before virus exposure. The ability of HIV to modulate the type I IFN-mediated innate immune response when it encounters a cell that has already been exposed to IFN remains poorly defined. The optimal pretreatment time (12 h) and the most potent HIV-inhibitors (e.g., IFN-α2 and -ω) were identified to investigate the ability of HIV to modulate an established type I IFN response. Gene expression at the level of the entire transcriptome was then compared between primary macrophages treated with type I IFNs, as opposed to treated with IFNs and then infected with HIV. Although HIV was not able to establish a robust infection, the virus was able to downregulate a number of IFN-stimulated genes (ISGs) with a fold change greater than 1.5 (i.e., AXL, IFI27, IFI44, IFI44L, ISG15, OAS1, OAS3, and XAF1). The downregulation of OAS1 by the presence of HIV was confirmed by real-time quantitative polymerase chain reaction. In conclusion, even though HIV replication is significantly inhibited by IFN pretreatment, the virus is able to downregulate the transcription of known antiviral ISGs (e.g., IFI44, ISG15, and OAS1).

Fluoroquinolone resistance in uncomplicated acute pyelonephritis: epidemiology and clinical impact

The objectives of this study were to investigate antibiotic resistance in urinary pathogens from Korean patients with uncomplicated acute pyelonephritis (UAPN), and to determine the effect of fluoroquinolone (FQ) resistance on clinical outcome in those patients with UAPN initially treated with FQ. Clinical and microbiologic data for all the APN patients attending 14 hospitals in South Korea in 2008 were collected retrospectively. Urinary pathogens were identified in 719 cases, and Escherichia coli was the most common pathogen (661/719, 91.9%). Antibiotic susceptibilities to several E. coli antibiotics were as follows: ciprofloxacin, 84.1%; trimethoprim-sulfamethoxazola (TMP-SMX), 67.2%; and extended-spectrum beta-lactamase-negative, 92.4%. FQ was the most frequent antibiotic prescribed for UAPN (45.3% intravenously and 53.9% by mouth). We compared clinical outcomes and hospital days in patients with FQ-resistant (32) and FQ-sensitive E. coli (173) who received FQ as initial empirical therapy. Clinical cure was higher in the FQ-sensitive group (78% vs. 91%, p=0.027), and hospital days were longer in the FQ-resistant group (9.6±5.5 days vs. 7±3.5 days, p=0.001). In conclusion, FQ-sensitivity of E. coli from UAPN was 84.1%. FQ treatment of UAPN caused by FQ-resistant E. coli has a lower cure rate and involves longer hospital stay than FQ treatment of cases caused by FQ-sensitive E. coli.

Immunogenicity and safety of trivalent inactivated influenza vaccine: a randomized, double-blind, multi-center, phase 3 clinical trial in a vaccine-limited country

Influenza vaccines are the primary method for controlling influenza and its complications. This study was conducted as a phase 3, randomized, double-blind, controlled, multi-center trial at seven university hospitals to evaluate the immunogenicity and safety of an inactivated, split, trivalent influenza vaccine (GC501, Green Cross Corporation, Yongin, Korea), which was newly manufactured in Korea in 2008. Between September 21 and 26, a total of 329 healthy subjects were recruited for the immunogenicity analysis, while 976 subjects were enrolled for the safety analysis. The GC501 vaccine met both FDA and EMEA criteria with ≥ 80% of subjects achieving post-vaccination titers ≥ 40 for all three subtypes, even in the elderly. The vaccine was well tolerated with only mild systemic and local adverse events. In summary, GC501 showed excellent immunogenicity and a good safety profile in both young adults and the elderly. The licensure of GC501 might be an important basis in preparation for the future influenza pandemic.

Immunogenicity and safety of influenza A (H1N1) 2009 monovalent inactivated split vaccine in Korea

In a pandemic, the development of an effective influenza vaccine is the most important subject from the view of public health. This study was performed to evaluate the immunogenicity and safety of inactivated, monovalent H1N1 2009 vaccine (Green Cross Corporation, Yongin, Korea) among healthy adults aged 19-64 years (Group 1) and the elderly aged ≥ 65 years (Group 2) in a two-dose regimen, 21 days apart. At baseline, 28 of 454 participants (6.1%) had hemagglutination-inhibition titers of ≥ 1:40 with no significant difference between age groups (p=0.27). There was an apparent dose-dependent antibody response; participants receiving the dose of 30 μg hemagglutinin (HA) showed higher geometric mean titers (GMTs) than the 15 μg HA group in both age groups. Despite the rates of seroprotection and seroconversion were significantly higher with 30 μg HA formulation than 15 μg HA formula in Group 2, there was no definite difference in Group 1 irrespective of vaccine formula. Significant GMT elevation after the second dose was not noted in either age group, regardless vaccine formulations. No deaths, vaccine-related serious adverse events, or immediate unsolicited adverse reactions occurred during the study periods.

Infectious complications in living-donor liver transplant recipients: a 9-year single-center experience

BACKGROUND

Infectious complications following living-donor liver transplantation (LDLT) remain a major cause of morbidity and mortality. We analyzed the frequency and type of infectious complications according to the post-transplantation period, and their risk factors with regard to morbidity and mortality.

METHODS

We retrospectively analyzed 208 subjects who had undergone LDLT during a 9-year period.

RESULTS

The rate of infection was 1.69 per patient during the study period. The predominant infections were intra-abdominal infections (37.6%), primary bacteremia (17.4%), and pneumonia (14.5%). Within the first post-transplant month, 140 (39.9%) infections were detected, and catheter-related coagulase-negative staphylococci (44) were the most common infectious agents. During the 2-6-month post-transplant period, 109 infectious episodes occurred (31.1%), and Enterococcus sp. (n=16) related to biliary infection was the most frequent isolate. After the sixth month, 96 infectious episodes (29%) occurred, and biliary tract-related Escherichia coli (n=19) was the major causative organism. The overall mortality was 24.5% (51/208); 1-year survival rate was 88% (196/208). Post-transplant infection-related mortality was 52.9% (27/51). Biliary tract complications, such as biliary stenosis or leakage, significantly increased the mortality (P=0.01); however, reoperation (retransplantation or resurgery for biliary tract obstruction/leakage or to control bleeding) significantly reduced the mortality (P=0.01).

CONCLUSIONS

Our data showed that early catheter removal would mainly aid in reducing infectious complications in the 1-month post-transplantation period. Aggressive management, including reoperation, would lower the mortality in the LDLT recipients.

Comparison of the MicroScan system and the agar dilution assay for Quinupristin/Dalfopristin susceptibility of Enterococcus faecium

We compared the results of Quinupristin/Dalfopristin (Q/D) susceptibility tests by the Positive Combo Panel (Type 11) of the MicroScan Walk Away 96 analyzer (Dade Behring, Inc.) with those obtained by the reference agar dilution method. From September 2003 to August 2004, a total of 410 E. faecium isolates were obtained from clinical samples. Of these, 65 (15.9%) strains were non-susceptible, and 345 (84.1%) strains were susceptible to Q/D. We collected consecutively 65 Q/D non-susceptible E. faecium isolates (42 resistant, 23 intermediate), and randomly selected 32 Q/D susceptible E. faecium isolates using the MicroScan system. The minimal inhibitory concentrations (MICs) of Q/D, vancomycin, and teicoplanin were determined by the agar dilution method according to CLSI guidelines. The agreement rates between the two methods were 100% for Q/D-susceptible strains, 85.7% for Q/D-resistant strains, and 26.1% for Q/D-intermediate strains of E. faecium. The major error rate (S-->R) was 11.9%, and the minor error rate (S-->I) was 13.0%. No very major errors were found. We conclude that for MicroScan 'non-susceptible' test results for Q/D, it is necessary to confirm the result using a reference method. The Q/D-resistance rate was higher in glycopeptide-susceptible (78.0% for vancomycin, 82.0% for teicoplanin) than glycopeptide-resistant E. faecium (22.0% for vancomycin, 16.0% for teicoplanin). Further studies are needed to determine whether Q/D use in hospitals or virginiamycin use in animals, or other factors, are responsible for the high rates of glycopeptide-susceptible and Q/D-resistant E. faecium strains in Korea.