Failure of Ciprofloxacin Therapy in the Treatment of Community-Acquired Acute Pyelonephritis caused by In-Vitro Susceptible Escherichia coli Strain Producing CTX-Type Extended-Spectrum β-Lactamase

While carbapenems are the drug of choice to treat extended-spectrum-β-lactamase (ESBL)-producing strains, some alternative carbapenem-sparing regimens are suggested for antibiotic stewardship. We experienced a case of ciprofloxacin treatment failure for acute pyelonephritis caused by an apparently susceptible Escherichia coli. A 71-year-old woman presented the emergency department with fever for 7 days and bilateral flank pain for 2 days. The laboratory results and abdominopelvic computed tomography finding were compatible with acute pyelonephritis. During 3-day ciprofloxacin therapy, the patient remained febrile with persistent bacteremia. After the change in antibiotics to ertapenem, the patient’s clinical course started to improve. ESBL-producing E. coli isolates were identified in all three consecutive blood samples. Pulsed-field gel electrophoresis (PFGE) patterns, serotypes, and sequence types showed the three isolates were derived from the identical strain. The isolates produced CTX-M-14 type ESBL belonging to the ST69 clonal group. Despite in vitro susceptibility, the failure was attributed to a gyrA point mutation encoding Ser83Leu within quinolone resistance-determining regions. This case suggests that ciprofloxacin should be used cautiously in the treatment of serious infections caused by ciprofloxacin-susceptible, ESBL-producing E. coli, even in acute pyelonephritis because in-vitro susceptibility tests could fail to detect certain genetic mutations.

Failure of Ciprofloxacin Therapy in the Treatment of Community-Acquired Acute Pyelonephritis caused by In-Vitro Susceptible Escherichia coli Strain Producing CTX-Type Extended-Spectrum β-Lactamase

While carbapenems are the drug of choice to treat extended-spectrum-β-lactamase (ESBL)-producing strains, some alternative carbapenem-sparing regimens are suggested for antibiotic stewardship. We experienced a case of ciprofloxacin treatment failure for acute pyelonephritis caused by an apparently susceptible Escherichia coli. A 71-year-old woman presented the emergency department with fever for 7 days and bilateral flank pain for 2 days. The laboratory results and abdominopelvic computed tomography finding were compatible with acute pyelonephritis. During 3-day ciprofloxacin therapy, the patient remained febrile with persistent bacteremia. After the change in antibiotics to ertapenem, the patient’s clinical course started to improve. ESBL-producing E. coli isolates were identified in all three consecutive blood samples. Pulsed-field gel electrophoresis (PFGE) patterns, serotypes, and sequence types showed the three isolates were derived from the identical strain. The isolates produced CTX-M-14 type ESBL belonging to the ST69 clonal group. Despite in vitro susceptibility, the failure was attributed to a gyrA point mutation encoding Ser83Leu within quinolone resistance-determining regions. This case suggests that ciprofloxacin should be used cautiously in the treatment of serious infections caused by ciprofloxacin-susceptible, ESBL-producing E. coli, even in acute pyelonephritis because in-vitro susceptibility tests could fail to detect certain genetic mutations.

Emergence of Community-Genotype Methicillin-Resistant Staphylococcus aureus in Korean Hospitals: Clinical Characteristics of Nosocomial Infections by Community-Genotype Strain

BACKGROUND: As community-genotype methicillin-resistant Staphylococcus aureus (MRSA) strains spread into hospitals, the genotypes of the MRSA strains causing hospital-acquired (HA) infections have become more diverse. We describe clinical characteristics of nosocomial MRSA infections by a community-genotype of sequence type (ST) 72. MATERIALS AND METHODS: A case-control study was designed among patients with HA-MRSA infections. Forty patients with infections caused by ST72-MRSA SCCmec type IV were selected as cases. Cases were matched to the controls with 106 patients infected with ST5/ST239 MRSA, which are representative hospital genotypes in Korea. RESULTS: Patients infected with ST72 isolates were younger than those with ST5/ST239 isolates. Female gender predominated among ST72 MRSA group compared to ST5/ST239 MRSA group. Solid tumor was a more frequent underlying disease in MRSA infections by ST72 isolates, whereas underlying renal, lung, heart, and neurologic diseases were more frequently found in those by ST5/ST239 isolates. The most common type of infection was pneumonia in both ST72 and ST5/ST239 groups (45.0% vs. 51.9%), followed by skin and soft tissue infection (SSTI). Female gender and underlying solid tumor were identified to be independent predictors for MRSA infections by ST72 isolates. All-cause mortality rates (20.0% vs. 30.2%) were not different between the groups. CONCLUSION: A community-genotype MRSA, ST72 isolate has emerged as a nosocomial pathogen presenting as hospital-acquired pneumonia and SSTI. Although differences in underlying disorders were found, the distribution of infection type and mortality rate did not differ between the groups.

Differential Cell Count and CRP Level in Blood as Predictors for Middle East Respiratory Syndrome Coronavirus Infection in Acute Febrile Patients during Nosocomial Outbreak

A case-control study was performed to identify clinical predictors for Middle East respiratory syndrome coronavirus (MERS-CoV) infection among patients with acute febrile illness during the nosocomial outbreak. Patients with MERS-CoV were more likely to have monocytosis with normal white blood cell (WBC) count and lower C-reactive protein (CRP) level. Simple laboratory data such as complete blood counts (CBC) with differential count could be a useful marker for the prediction of MERS and triage at the initial presentation of acute febrile patients in outbreak setting.

Importance of Specimen Type and Quality in Diagnosing Middle East Respiratory Syndrome

No abstract available.

Diagnostic yield of computed tomography-guided bone biopsy and clinical outcomes of tuberculous and pyogenic spondylitis

BACKGROUND/AIMS: This study aimed to evaluate the efficacy of computed tomography (CT)-guided bone biopsy for the diagnosis of spinal infection and compared the clinical outcomes between tuberculous and pyogenic spinal infections. METHODS: The retrospective cohort study included patients who received CT-guided bone biopsy at a tertiary hospital over the 13 years. RESULTS: Among 100 patients, 67 had pyogenic spondylitis and 33 had tuberculous spondylitis. Pathogens were isolated from bone specimens obtained by CT-guided biopsy in 42 cases, with diagnostic yields of 61% (20/33) for tuberculous spondylitis and 33% (22/67) for pyogenic spondylitis. For 36 culture-proven pyogenic cases, Staphylococcus aureus was the most commonly isolated organism. Patients with pyogenic spondylitis more frequently presented with fever accompanied by an increase in inflammatory markers than did those with tuberculosis. Among all patients who underwent surgery, the incidence of late surgery performed one month after diagnosis was higher in patients with tuberculous infection (56.3%) than in those with pyogenic disease (23.3%, p = 0.026). CONCLUSIONS: Results obtained by CT-guided bone biopsy contributed to prompt diagnoses of spinal infections, especially those caused by tuberculosis. Despite administration of anti-tuberculous agents, patients with tuberculous spondylitis showed an increased tendency to undergo late surgery.

Possible Transfusion-Related Acute Lung Injury Following Convalescent Plasma Transfusion in a Patient With Middle East Respiratory Syndrome

No abstract available.

A Case of Bacteremia Caused by Dialister pneumosintes with Streptococcus anginosus / 대한임상미생물학회지

Dialister pneumosintes is a nonfermentative, gram-negative anaerobic rod which is considered as a commensal organism of the oral cavity. A 77-year-old man with a history of aortic stenosis was visited to ER for dyspnea and fever. D. pneumosintes and Streptococcus anginosus were isolated from blood culture, and also D. pneumosintes was identified by 16S rRNA-based gene sequencing. This case report is the first case of isolation of D. pneumosintes from blood in Korea, and highlights the usefulness of DNA sequencing to identify pathogens in organism which is difficult to identify by biochemical identification method.

Native valve endocarditis due to extended spectrum beta-lactamase producing Klebsiella pneumoniae

No abstract available.

Identification of Erysipelothrix rhusiopathiae by DNA Sequencing in a Culture-Negative Intra-Abdominal Abscess / 대한임상미생물학회지

Erysipelothrix rhusiopathiae is a Gram-positive bacillus that causes infections primarily in animals. In humans, the bacteria usually cause localized or generalized cutaneous infections. A 75-year-old man with chronic alcoholism presented with abdominal pain. Abdominal computed tomography and laboratory findings suggested an intra-abdominal abscess in the periaortic soft tissue. While no definitive infectious source was identified, E. rhusiopathiae was identified by 16S rRNA-based gene sequencing from culture-negative, periaortic necrotic tissue, subsequent to empiric antibiotic treatment. It is suggested that E. rhusiopathiae has the potential to cause intra-abdominal abscesses. This case report highlights the usefulness of DNA sequencing to identify pathogens in patients pretreated with antibiotics.

Infection Prevention in Transplant Recipients / 대한내과학회지

Opportunistic infections are major causes of morbidity and mortality in hematopoietic stem-cell transplant and solid organ transplant recipients. The epidemiology and incidence of opportunistic infections in those patients have been dramatically changed with use of potent immunosuppressive agents as well as routine prophylaxis against various microorganisms such as common bacterial pathogens, fungi, cytomegalovirus, Pneumocystis jirovecii, and so on. Because transplant recipients are at the greatest risk for infection during early phase (1-3 months) after transplant, safe and effective prevention strategies should be implemented in this period. Moreover, beyond early phase, recipients are often susceptible to infections due to prolonged immunosuppressive therapy for graft rejection or chronic graft-versus-host diseases. Therefore, clinicians should assess a recipient's risk of infection on the basis of concomitant graft function, intensity of immunosuppression, and other factors that may contribute to susceptibility to infections. We discussed infection prevention strategies among recipients of hematopoietic stem-cell and solid organ transplantation against various opportunistic pathogens. Vaccinations should also be recommended for pre-transplant candidates and post-transplant recipients for the best prevention of infections.

Clinical and Microbiological Characteristics of Healthcare-Associated Infections in Community-Onset Klebsiella pneumoniae Bacteremia

BACKGROUND: Although healthcare-associated (HCA) Klebsiella pneumoniae bacteremia constitutes a significant proportion of community-onset infection cases, its clinical and microbiologic characteristics have yet to be described in detail. In this study, we sought to delineate the clinical differences between community-associated (CA) and HCA K. pneumoniae bacteremia. MATERIALS AND METHODS: A total of 240 patients infected by community-onset K. pneumoniae bacteremia were included in this study, and the data from the patients with HCA K. pneumoniae bacteremia were compared to those with the CA bacteremia. Isolates were microbiologically characterized and serotyped using a PCR method. RESULTS: Of the total 240 patients infected with community-onset K. pneumoniae bacteremia, 140 (58.3%) were defined as HCA infection cases, and the remaining 100 patients were classified as CA infections. Multivariate analysis showed that use of percutaneous tubes, occurrence of a recent surgical operation, cases of pneumonia, neutropenia and solid tumor, and prior receipt of antibiotics were all significant factors associated with HCA bacteremia infection (all P<0.05). In terms of microbiologic characteristics, ciprofloxacin resistance (12.9% [18/140] vs. 4.0% [4/100], P=0.02) and extended-spectrum beta-lactamase production (12.1% [17/140] vs. 4.0% [4/100], P=0.03) were more common in HCA bacteremia than CA bacteremia, respectively. The K1 and K2 serotypes, which are considered virulent community strains, were observed to exist more frequently in CA bacteremia than in HCA bacteremia (34% [34/100] vs. 21.4% [30/140], P=0.03). The overall 30-day mortality of the study population was 17.5% (37/211), and there was a trend toward greater mortality in the HCA group than in the CA group (21.4% [27/126] vs. 11.8% [10/85]; P=0.07). CONCLUSIONS: Patients infected with HCA bacteremia accounted for a substantial proportion of all patients with community-onset K. pneumoniae bacteremia, and showed significantly different clinical and microbiological characteristics than those infected with CA bacteremia. HCA K. pneumoniae bacteremia represented a distinct subset of community-onset bacteremia characterized by antibiotic resistant pathogens, a finding which physicians should consider in providing optimal treatment of these cases.

A Case of an Infected Pseudoaneurysm with Complications Due to A Non-Typhoidal Salmonella Species / 대한내과학회지

Non-typhoidal Salmonella infections, which rarely present with multiple complications, are predominantly seen in immunocompromised patients. In particular, non-typhoidal Salmonella infections presenting with more than two complications are extremely rare. Here, we report a case of an infected pseudoaneurysm in the aortic arch caused by a non-typhoidal Salmonella species complicated by pleural empyema, pericarditis, pericardial empyema, and mediastinitis. To our knowledge, this is the first such case report in Korea.

Post-influenza Pneumonia Caused by the USA300 Community-Associated Methicillin-Resistant Staphylococcus aureus in Korea

Panton-Valentine leukocidin (PVL)-positive USA300 clone has been the most successful community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) clone spreading in North America. In contrast, PVL-negative ST72-CA-MRSA has been predominant in Korea, and there has been no report of infections by the USA300 strain except only one case report of perianal infection. Here, we describe the first case of pneumonia caused by the USA300 strain following pandemic influenza A (H1N1) in Korea. A 50-year-old man was admitted with fever and cough and chest radiograph showed pneumonic consolidation at the right lower lung zone. He received a ventilator support because of respiratory failure. PCR for pandemic influenza A (H1N1) in nasopharyngeal swab was positive, and culture of sputum and endotracheal aspirate grew MRSA. Typing of the isolate revealed that it was PVL-positive, ST 8-MRSA-SCCmec type IV. The analysis of the PFGE patterns showed that this isolate was the same pulsotype as the USA300 strain.

Septicemic Melioidosis Presenting as Head and Neck Abscesses

Melioidosis is a life-threatening disease caused by Burkholderia pseudomallei , which is endemic in Southeast Asia and Northern Australia. It may manifest as a pulmonary lesion, osteomyelitis, septicemia, or abscesses of soft tissue or various organs. However, soft tissue abscess associated with bacteremia, especially those found in the head and neck, are rarely reported. We report a case of disseminated septicemia due to Burkholderia pseudomallei presenting as head and neck abscesses in a 55-year-old Korean man with a history of working in Malaysia. This is the first report of fatal melioidosis presenting as a complicated skin and soft tissue infection, in Korea.

A Case of Intra-Abdominal Kikuchi's Disease with Increased FDG Uptake on PET-CT that Mimicked Intra-Abdominal Lymphoma

Kikuchi's disease is a benign disease characterized mainly by fever and cervical lymphadenitis. We report a case of Kikuchi's disease that manifested as intra-abdominal lymphadenitis. A 39 year old woman presented with fever that had persisted for one week. Her history and physical examination were unremarkable. The laboratory findings revealed mild leukopenia and increased C-reactive protein. Abdominal CT revealed multiple lymph node enlargements in the mesenteric root and around the ileocecal valve. Positron emission tomography-computed tomography (PET-CT) revealed increased 18-fluoro-deoxyglucose(FDG) uptake in the lymph nodes observed by abdominal CT. A laparoscopic excisional biopsy of the lymph node was performed for a confirmatory diagnosis and the pathology findings were compatible with Kikuchi's disease. Although intra-abdominal Kikuchi's disease is a rare disease, it should be considered in a differential diagnosis of intra-abdominal lymphadenopathy with increased FDG uptake on PET-CT.

Epidemiology of Ciprofloxacin Resistance and Its Relationship to Extended-Spectrum beta-Lactamase Production in Proteus mirabilis Bacteremia

BACKGROUND/AIMS: We evaluated the clinical features of ciprofloxacin-resistant Proteus mirabilis bacteremia and risk factors for ciprofloxacin resistance. METHODS: From October 2000 to July 2009, 37 patients with clinically significant P. mirabilis bacteremia were identified and data from patients with ciprofloxacin-resistant and ciprofloxacin-susceptible P. mirabilis bacteremia were compared. RESULTS: The most common underlying diseases were neurologic disease (37.8%) and solid tumors (29.7%). The most common site of infection was the urinary tract (35.1%). Ten of the 37 patients (27.0%) were infected with ciprofloxacin-resistant isolates, and univariate analysis revealed a significant relationship between ciprofloxacin-resistant P. mirabilis bacteremia and neurologic disease, recent operation, L-tube insertion, percutaneous tube use, and extended-spectrum beta-lactamase (ESBL) production (all p < 0.05). ESBL was detected in six of 10 (60%) ciprofloxacin-resistant isolates, while only three of 27 (11%) ciprofloxacin-susceptible isolates produced ESBL (p = 0.005). In a logistic regression analysis, ESBL production remained a significant factor associated with ciprofloxacin resistance, after adjusting for other variables. CONCLUSIONS: These data indicate a close association between ciprofloxacin resistance and ESBL-production in P. mirabilis bacteremia. This association is particularly troublesome because the therapeutic options for serious infections caused by ESBL-producing P. mirabilis are severely restricted.

Native Valve Infective Endocarditis due to Staphylococcus lugdunensis Confirmed by 16S Ribosomal RNA Sequencing

Staphylococcus lugdunensis is a Gram-positive, coagulase-negative Staphylococcus (CNS) species that is found as a skin commensal and has been implicated in fulminant invasive diseases such as infective endocarditis. S. lugudunensis infections resemble Staphylococcus aureus infections in terms of virulence, tissue destruction and clinical course. Although correct identification and determination of the susceptibility profile are important, some commercial systems may misidentify S. lugdunensis. We report a case of native valve infective endocarditis caused by S. lugdunensis, which was misidentified by the Vitek 2 system but identified correctly by 16S ribosomal RNA (rRNA) gene sequencing in a 72-year-old male patient. The patient had multiple vegetations on his mitral valve, and the largest one was found on the posterior mitral valve leaflet. It was 2.5 cm in size and hypermobile. Diffuse valvular abscess was also observed. He had persistent bacteremia for appoximately 8 days, which was resolved after immediate surgery and antibiotic therapy. When a patient with severe sepsis syndrome grows S. aureus or CNS other than S. lugdunensis on a commercial automatic culture system, the possibility of S. lugdunensis should be considered and further confirmatory testing such as 16S rRNA sequencing may be very useful.

Usefulness of C-Reactive Protein for Evaluating Clinical Outcomes in Cirrhotic Patients with Bacteremia

BACKGROUND/AIMS: The purpose of this study was to evaluate the value of initial C-reactive protein (CRP) as a predictor of clinical outcome and to investigate whether follow-up CRP measurement is useful for the prediction of the clinical outcome of bloodstream infections in patients with liver cirrhosis (LC), whose CRP production in response to infection may be attenuated. METHODS: A retrospective, observational study including 202 LC patients with Escherichia coli or Klebsiella pneumoniae bacteremia was conducted to assess the usefulness of serial CRP measurements in predicting clinical outcome in LC patients. The CRP ratio was defined as the ratio of the follow-up CRP level to the initial CRP level. RESULTS: The overall 30-day mortality rate of the study population was 23.8% (48/202). In the multivariate analysis, advanced age (> or = 70 years), healthcare-associated or nosocomial infections, model for end-stage liver disease (MELD) score of > or = 30, and initial body temperature of or = 0.7 was found to be a significant factor associated with mortality (odds ratio, 19.12; 95% confidence interval, 1.32 to 276.86; p = 0.043) after adjusting for other confounding variables. CONCLUSIONS: Initial CRP level did not predict mortality of sepsis in LC patients. However, serial CRP measurements during the first week of antimicrobial therapy may be useful as a prognostic factor for mortality in LC patients.

An Adult Case of Chronic Active Epstein-Barr Virus Infection with Interstitial Pneumonitis

Chronic active Epstein-Barr virus (CAEBV) infection is characterized by persistent infectious mononucleosis-like symptoms, an unusual pattern of Epstein-Barr virus (EBV) antibodies, detection of the EBV genome in affected tissues or peripheral blood, and chronic illness that cannot be attributed to any other known disease. This is the first reported Korean case of an immunocompetent adult with CAEBV-associated interstitial pneumonitis. A 28-year-old female was admitted with a fever that persisted for 3 weeks. She had multiple lymphadenopathy, hepatosplenomegaly, pancytopenia, and elevated serum aminotransferase levels. Serology for antibodies was positive and chest computed tomography showed diffuse ground glass opacities in both lungs. Histopathology of the lung tissue showed lymphocyte infiltration, and EBV DNA was detected in those lymphocytes using in situ hybridization with an EBV-encoded RNA probe. After 1 month of hospitalization, she improved without specific treatment.