Chun-Wen Cheng

Clinical significance and outcomes of Clostridium perfringens bacteremia—a 10-year experience at a tertiary care hospital

BACKGROUND The mortality rate of patients with Clostridium perfringens bacteremia is 27-44%. Typically, the clinical characteristics of this infection are non-specific, which leads to considerable difficulty with the diagnosis and early initiation of appropriate therapy. METHODS A retrospective cohort study of patients who were hospitalized between August 2002 and July 2011 with C. perfringens bacteremia was conducted within a 3715-bed teaching hospital in northern Taiwan. The patients identified in this search were included when they had fever or other clinical features suggestive of systemic infection. Multiple logistic regression analysis was applied to determine the independent risk factors of 30-day mortality. RESULTS A total of 93 patients were identified. Elderly patients with comorbid illnesses, especially renal insufficiency or malignancy, were at risk of developing C. perfringens bacteremia, and 23 patients (24.7%) had nosocomial bacteremia. The 30-day and attributed mortalities were 26.9% (25/93) and 8.6% (8/93), respectively. Nosocomial infection was a significant predictor for mortality within 30 days (odds ratio 19.378, 95% confidence interval 2.12-176.99; p=0.009), independent of other disease parameters. Other independent risk factors included the Charlson weighted index of comorbidity, length of hospitalization, and stay in the intensive care unit. CONCLUSIONS Early recognition of this critical infection and early initiation of appropriate antibiotic treatment by surgical intervention or drainage is essential.

Clinical experience and microbiologic characteristics of invasive Staphylococcus lugdunensis infection in a tertiary center in northern Taiwan

BACKGROUND/PURPOSE Staphylococcus lugdunensis is a coagulase-negative staphylococcus that cannot be ignored. This study is a comprehensive analysis of the clinical and microbiological characteristics of S. lugdunensis bacteremia and sterile site infection during hospitalization. METHODS This retrospective study included 48 patients with invasive S. lugdunensis infection. During the period of March 2002 to July 2012, they had been hospitalized in a tertiary center of northern Taiwan. Demographics, clinical characteristics, and risk factors of mortality were analyzed. All isolates were tested for antimicrobial susceptibility. We identified the staphylococcal cassette chromosome mec (SCCmec) gene for oxacillin nonsusceptible isolates. RESULTS The incidence of S. lugdunensis in coagulase-negative staphylococci bacteremia was 0.87%. Forty-eight patients were enrolled: S. lugdunensis was present in 41 patients with bacteremia, in the ascites of three patients, in the synovial fluid of two patients, in the pleural effusion of one patient, and in the amniotic fluid of one patient. The three most common sources of infection were primary bacteremia (43.8%), catheter-related infection (18.8%), and vascular graft infection (12.5%). All-cause mortality during hospitalization was 20.8% (10/48). All deceased patients were bacteremic. Risk factors associated with in-hospital mortality included a Pittsburgh bacteremia score of 2 or greater, infective endocarditis, and end-stage renal disease. Ten (20.8%) isolates were resistant to oxacillin, and 8 isolates were classified as SCCmec type V. CONCLUSION The clinical significance of S. lugdunensis should not be ignored, especially in patients with severe comorbidities. An aggressive search for endocarditis is strongly suggested in S. lugdunensis bacteremic cases.

Characteristics and outcomes of Fusobacterium nucleatum bacteremia—a 6-year experience at a tertiary care hospital in northern Taiwan

Fusobacterium nucleatum bacteremia is critical and not well defined. To identify the clinical characteristics and outcomes, we conducted a retrospective review of hospitalized patients from January 2004 to December 2009 at a tertiary center in northern Taiwan. Fifty-seven patients were enrolled. The mean age was 58.1 years, and the mean Pitt bacteremia score was 4.7. Males predominated (59.6%), and the overall 30-day mortality rate was up to 47.4%. Malignancy was the major comorbidity (26/57, 45.6%), especially oropharyngeal and gastrointestinal cancers (19/26, 73.1%). Pneumonia (17/57, 29.8%) was the most common presentation with high rates of respiratory failure (15/17, 88.2%) and mortality (11/17, 64.7%), followed by intra-abdominal infections (7/57, 12.3%). In multivariate analysis, higher Pitt bacteremia score, nosocomial infection, anemia, and intensive care unit stay were the independent factors for 30-day mortality. Nosocomial F. nucleatum bacteremia was a significant mortality predictor independent to other parameters of disease severities.

Molecular Characteristics of Disease-Causing and Commensal Staphylococcus lugdunensis Isolates from 2003 to 2013 at a Tertiary Hospital in Taiwan

Objectives Staphylococcus lugdunensis can cause community- and healthcare-associated infections. This study investigated the molecular characteristics of S. lugdunensis isolates collected at our hospital and compared the characteristics of the infectious and commensal isolates. Methods We collected the S. lugdunensis isolates between 2003 and 2013. The antimicrobial resistance test, SCCmec typing, accessory gene regulator (agr) typing, pulsed-field gel electrophoresis (PFGE), and δ-like hemolysin activity were performed. Results In total, 118 S. lugdunensis isolates were collected, of which 67 (56.8%) were classified into the infection group and 51 (43.2%) into the commensal group. The oxacillin resistance rate was 36.4%. The most common SCCmec types were SCCmec types V (51.4%) and II (32.6%). In total, 34 pulsotypes were identified. The PFGE typing revealed five clones (pulsotypes A, J, M, N, and P) at our hospital. Pulsotypes A and N caused the spread of high oxacillin resistance. In total, 10.2% (12 of 118) of the isolates lacked δ-like hemolysin activity. Compared with the infection group, the commensal group showed a higher percentage of multiple drug resistance and carried a higher percentage of SCCmec type II (11 of 22, 50% and 3 of 21, 14.3%) and a lower percentage of SCCmec type V (8 of 22, 36.4% and 14 of 21, 66.7%). The commensal group (27 PFGE types) showed higher genetic diversity than did the infection group (20 PFGE types). No difference was observed in the distribution of the five main pulsotypes, agr typing, and the presence of δ-like hemolysin activity between the two groups. Conclusions Five main clones were identified at our hospital. The commensal group showed higher genetic diversity, had a higher percentage of multidrug resistance, and carried a higher percentage of SCCmec type II and a lower percentage of SCCmec type V than did the infection group.

Sulbactam treatment for pneumonia involving multidrug-resistant Acinetobacter calcoaceticus–Acinetobacter baumannii complex

Abstract Background: Multidrug-resistant (MDR) Acinetobacter calcoaceticus–Acinetobacter baumannii (Acb) complex has become an important cause of nosocomial pneumonia. Sulbactam is a β-lactamase inhibitor with antimicrobial activity against MDR Acb complex. Methods: To investigate outcomes of pneumonia involving MDR Acb complex treated with sulbactam or ampicillin/sulbactam for at least 7 days, we conducted a retrospective study of 173 adult patients over a 34 month period. Results: Of 173 patients, 138 (79.8%) received combination therapy, mainly with carbapenems (119/138, 86.2%). The clinical response rate was 67.6% and the 30 day mortality rate was 31.2%. The independent predictors of clinical failure were malignancy, bilateral pneumonia and shorter duration of treatment. In patients with sulbactam-susceptible strains, there was no difference in clinical and microbiological outcome between combination therapy and monotherapy. Compared to the sulbactam-susceptible group, the sulbactam-resistant group had a lower rate of airway eradication, a longer duration of treatment and a higher rate of combination therapy with predominantly carbapenems (p < 0.05). There was no significant difference between the two groups in clinical resolution and 30 day mortality rates. Conclusions: Sulbactam could be a treatment option for pneumonia involving MDR Acb complex, and combination therapy with carbapenems could be considered for sulbactam-resistant cases.

Clinical Features, Outcomes, and Molecular Characteristics of Community- and Health Care-Associated Staphylococcus lugdunensis Infections

ABSTRACT Staphylococcus lugdunensis is a major cause of aggressive endocarditis, but it is also responsible for a broad spectrum of infections. The differences in clinical and molecular characteristics between community-associated (CA) and health care-associated (HA) S. lugdunensis infections have remained unclear. We performed a retrospective study of S. lugdunensis infections between 2003 and 2014 to compare the clinical and molecular characteristics of CA and HA isolates. We collected 129 S. lugdunensis isolates in total: 81 (62.8%) HA isolates and 48 (37.2%) CA isolates. HA infections were more frequent than CA infections in children (16.0% versus 4.2%, respectively; P = 0.041) and the elderly (38.3% versus 14.6%, respectively; P = 0.004). The CA isolates were more likely to cause skin and soft tissue infections (85.4% versus 19.8%, respectively; P < 0.001). HA isolates were more frequently responsible for bacteremia of unknown origin (34.6% versus 4.2%, respectively; P < 0.001) and for catheter-related bacteremia (12.3% versus 0%, respectively; P = 0.011) than CA isolates. Fourteen-day mortality was higher for HA infections than for CA infections (11.1% versus 0%, respectively). A higher proportion of the HA isolates than of the CA isolates were resistant to penicillin (76.5% versus 52.1%, respectively; P = 0.004) and oxacillin (32.1% versus 2.1%, respectively; P < 0.001). Two major clonal complexes (CC1 and CC3) were identified. Sequence type 41 (ST41) was the most common sequence type identified (29.5%). The proportion of ST38 isolates was higher for HA than for CA infections (33.3% versus 12.5%, respectively; P = 0.009). These isolates were of staphylococcal cassette chromosome mec element (SCCmec)type IV, V, or Vt. HA and CA S. lugdunensis infections differ in terms of their clinical features, outcome, antibiotic susceptibilities, and molecular characteristics.

The clinical outcomes of oldest old patients with tuberculosis treated by regimens containing rifampicin, isoniazid, and pyrazinamide

Objectives To investigate the clinical characteristics, adverse drug reactions, and outcomes of the oldest old patients (aged ≥80 years) with tuberculosis (TB) treated with rifampicin, isoniazid, and pyrazinamide (RIP)-containing regimens. Design A retrospective chart review study. Setting A 1,200-bed tertiary teaching hospital in southwest Taiwan. Participants We conducted a retrospective observational study between January 1, 2005 and December 31, 2011. Seven hundred adult patients (aged ≥18 years) with TB treated with RIP-containing anti-TB regimens were reviewed, including 161 oldest old patients. Outcome measures Clinical outcomes included clinical responsiveness and microbiological eradication. Adverse outcomes included drug-induced hepatitis, and other symptoms included gastrointestinal upset (eg, abdominal pain, vomiting, diarrhea, or dyspepsia), skin rash, joint pain, and hyperuricemia. Results Compared with the non-oldest old adult patients, the oldest old patients more frequently had hepatitis (P=0.014), gastrointestinal upset (P=0.029), and unfavorable outcomes (P<0.001). In a multivariate analysis, hepatitis during treatment (adjusted odds ratio: 3.482, 95% confidence interval: 1.537–7.885; P<0.003) and oldest old age (adjusted odds ratio: 5.161, 95% confidence interval: 2.294–11.613; P<0.010) were independent risk factors for unfavorable outcomes. In the oldest old patients with hepatitis, rifampicin use was more common in the favorable outcome group than in the unfavorable outcome group (100% vs 37.5%; P=0.001). Conclusion The oldest old age and hepatitis during RIP treatment were associated with unfavorable outcomes. For the oldest old patients with TB having hepatitis during treatment, rifampicin rechallenge and use might benefit the treatment outcome.

Persistence of a major endemic clone of oxacillin-resistant Staphylococcus lugdunensis sequence type 6 at a tertiary medical centre in northern Taiwan.

OBJECTIVES The aim of this study was to investigate the molecular epidemiology and clinical characteristics of a major clone of oxacillin-resistant Staphylococcus lugdunensis in a tertiary hospital. METHODS All S. lugdunensis isolated from sterile sites between June 2003 and May 2013 were collected for analysis. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed to study their genetic relationships. RESULTS A total of 118 S. lugdunensis isolates were analysed by PFGE. Three major PFGE pulsotypes were found: A, H, and L. Most of the pulsotype A isolates were oxacillin-resistant, and SCCmec type V and type VT. Isolates from another major clonal group that consisted primarily of pulsotype L were oxacillin-resistant and SCCmec type II. These 14 SCCmec type II S. lugdunensis isolates demonstrated high PFGE similarity and were obtained in the study hospital over a period of 40 months. Three of these 14 patients had clinically significant bacteraemia, and all three cases were in the intensive care unit. Further MLST analysis of the isolates identified an endemic S. lugdunensis strain of sequence type 6, clonal complex 1. CONCLUSIONS This study identified a major endemic clone of S. lugdunensis that is oxacillin-resistant, SCCmec type II, ST6, and capable of long-term persistence in the hospital. Continuous infection control surveillance and monitoring of S. lugdunensis should be considered in endemic areas.

Coexistence of fatal disseminated invasive aspergillosis and pyoderma gangrenosum: a case report.

Objective: To report an unusual case of disseminated aspergillosis involving the lymph nodes, lungs, and skin in a patient with pyoderma gangrenosum (PG) and myelodysplastic syndrome (MDS). Case Presentation and Intervention: A 46-year-old man presented with productive cough of 2 weeks’ duration. Besides, several painless, fixed lymph nodes were palpated at his left neck. He had PG and MDS diagnosed in June 2004 with regular use of oral dapsone and prednisolone. His skin lesions healed with scar formation and no purulent discharge. A computed tomography scan of the head, neck and chest showed bilateral lung consolidation and abscesses at the left neck, right upper lung and right pleura. The neck abscess culture grew Aspergillus species. Dark reddish macules developed over the right arm, chest and abdominal wall, and the left lower limb 2 weeks after initiation of amphotericin B. The histology of the right arm skin biopsy showed invasive aspergillosis. Caspofungin was started then for suspicion of poor response to amphotericin B. He expired despite 35 days of antifungal therapy. Conclusion: This report highlights the rarity of coexistence of disseminated aspergillosis and PG, and should alert physicians to the possibility of invasive fungal infection superimposed on a chronic skin lesion.