Acquisition and clearance of multidrug resistant Acinetobacter baumannii on healthy young adults concurrently burned in a dust explosion in Taiwan: the implication for antimicrobial stewardship.

BACKGROUND: Information is limited about the effect of restricted carbapenem use on clearance of multi-drug resistant Acinetobacter baumannii (MDRAB). We sought to determine the time effect of antibiotic exposure on multi-drug resistant Acinetobacter baumannii (MDRAB) acquisition and clearance. METHODS: We conducted a retrospective observational study at the intensive care units of a tertiary medical center. Forty-two of a cohort of previously healthy young adults who were concurrently burned by a dust explosion was included. Cases consisted of those from whom MDRAB was isolated during hospitalization. Controls consisted of patients from whom MDRAB was not isolated in the same period. Use of antimicrobial agents was compared based on days of therapy per 1,000 patient-days (DOT/1,000PD). A 2-state Markov multi-state model was used to estimate the risk of acquisition and clearance of MDRAB. RESULTS: MDRAB was discovered in 9/42 (21.4%) individuals. The cases had significantly higher use of carbapenem (652 DOT/1,000PD vs. 385 DOT/1,000PD, P < 0.001) before MDRAB isolation. For the cases, clearance of MDRAB was associated with lower use of carbapenem (469 DOT/1,000PD vs. 708 DOT/1,000PD, P = 0.003) and higher use of non-carbapenem beta-lactam (612 DOT/1,000PD vs. 246 DOT/1,000PD, P <0.001). In multi-state model, each additional DOT of carbapenem increased the hazard of acquiring MDRAB (hazard ratio (HR), 1.08; 95% confidence interval (CI) 1.01-1.16) and each additional DOT of non-carbapenem beta-lactam increased the protection of clearing MDRAB (HR, 1.25; 95% CI 1.07-1.46). CONCLUSIONS: Both acquisition and clearance of MDRAB were related to antibiotic exposure in a homogeneous population. Our findings suggest that early discontinuation of carbapenem could be an effective measure in antibiotic stewardship for the control of MDRAB spreading.

Influence of borderline cefepime MIC on the outcome of cefepime-susceptible Pseudomonas aeruginosa bacteremia treated with a maximal cefepime dose: a hospital-based retrospective study.

BACKGROUND: We assessed the influence of current cefepime minimal inhibitory concentration (MIC) breakpoints and the maximal cefepime dose on treatment outcomes in patients with bacteremia caused by cefepime-susceptible Pseudomonas aeruginosa. METHODS: Adult patients hospitalized between July 2010 and June 2014 with a positive blood culture for cefepime-susceptible P. aeruginosa and receipt of cefepime as the primary therapy throughout the course were reviewed. Cefepime Etest® MICs and clinical outcomes for P. aeruginosa bacteremia were reviewed to identify the MIC breakpoint influencing treatment outcomes. RESULTS: Of the 90 patients enrolled, 49 (54.4%) were male (mean age = 66.8 years). The mean Acute Physiology and Chronic Health Evaluation II score was 22.01. Sixty patients (66.7%) received a maximal cefepime dose, and the 30-day crude mortality rate was 36.7%. MIC90 of cefepime for P. aeruginosa was 8 mg/L. The cumulative survival rate at 30 days revealed that a lower cefepime MIC (<4 mg/L) for P. aeruginosa was associated with a higher survival rate than a higher MIC (≥4 mg/L) (72.6% vs. 23.5%, p < 0.0001). A cefepime MIC of ≥4 mg/L and age were independent risk factors for mortality, whereas the maximal cefepime dose was the independent protective factor. The use of a maximal cefepime dose did not improve the outcomes of patients with P. aeruginosa bacteremia at a MIC of ≥4 mg/L. CONCLUSIONS: A cefepime MIC of 4 mg/L may predict an unfavorable outcome among patients with serious infections caused by P. aeruginosa, even the MICs still within the CLSI susceptibility breakpoint.

Tigecycline-based versus sulbactam-based treatment for pneumonia involving multidrug-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii complex.

BACKGROUND: The treatment options for pneumonia involving multidrug-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii (MDR Acb) complex are limited, and the optimal treatment has not been established. METHODS: To compare the efficacy of tigecycline-based with sulbactam (or ampicillin/sulbactam)-based therapy for pneumonia involving MDR Acb complex, we conducted a retrospective study comparing 84 tigecycline-treated adult patients during the period August 2007 to March 2010 with 84 sulbactam or ampicillin/sulbactam-treated adult patients during the period September 2004 to July 2007. Both groups had the matched Acute Physiology and Chronic Health Evaluation (APACHE) II score and received treatment for at least 7 days. RESULTS: The mean APACHE II score was 20.1 for both groups. More patients in sulbactam group had ventilator use (89.3 % versus 69.0 %), bilateral pneumonia (79.8 % versus 60.7 %) and combination therapy (84.5 % versus 53.6 %), particularly with carbapenems (71.4 % versus 6.0 %), while more patients in tigecycline group had delayed treatment (41.7 % versus 26.2 %) (P <0.05). At the end of treatment, more patients in sulbactam group had airway MDR Acb complex eradication (63.5 % versus 33.3 %, P <0.05). The clinical resolution rate was 66.7 % for both groups. The mortality rate during treatment was 17.9 % in sulbactam group, and 25.0 % in tigecycline group (P = 0.259). The multivariate analysis showed that bilateral pneumonia was the only independent predictor for mortality during treatment (adjusted odds ratio, 2.717; 95 % confidence interval, 1.015 to 7.272). CONCLUSIONS: Patients treated with either tigecycline-based or sulbactam-based therapy had a similar clinical outcome, but tigecycline group had a lower microbiological eradiation rate.

Investigation of a cluster of Legionnaires' disease during the outbreak of coronavirus disease 2019 pandemic in northeastern Taiwan, June 2021.

PURPOSE: To describe the investigation and intervention of a cluster of Legionnaires' disease detected during the outbreak of coronavirus disease 2019 (COVID-19) pandemic. METHODS: From June 7 to 22, 2021, 15 cases in the neighborhood near our hospital were detected. Information about residence, workplace, hospital visit, and potential exposures was collected. Sampling and decontamination were performed for potential sources. RESULTS: All 15 patients had pneumonia when visiting the emergency room with negative COVID-19 test results. Most patients were male (73.3%) with the mean age of 65.7 years. The most common comorbidities were diabetes mellitus (40.0%) and hypertension (40%). The most common symptom was fever (93.3%). Two (13.3%) patients needed mechanical ventilators. Fever subsided within 2 days of treatment for most cases (85.7%). Five cases had exposure history at our hospital, and the other 10 lived or worked in the area within 2 km of our hospital, mostly in buildings A and B. Water sampling was carried out for our hospital, buildings A and B; one water sample from a cooling tower in our hospital cultured positive for Legionella bacteria. Early testing and treatment for suspected cases were carried out for the outbreak, and all cases were discharged with pneumonia resolution. CONCLUSION: This was a community outbreak of Legionnaires' disease near our hospital. COVID-19 tests were repeated frequently before testing for Legionnaires' disease during the COVID-19 pandemic. Early recognition of Legionnaires' disease and timely treatment improved outcome.

Neutralization Assessments Reveal High Cardiothoracic Ratio and Old Age as Independent Predictors of Low Neutralizing Antibody Titers in Hemodialysis Patients Receiving a Single Dose of COVID-19 Vaccine.

BACKGROUND: Data are lacking regarding predictors of quantification of neutralizing antibodies (nAbs) based on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 50% neutralization titer (NT50) after a single dose of COVID-19 vaccine in hemodialysis (HD) patients. METHODS: This prospective single-center study enrolled 200 HD patients and 82 healthy subjects to estimate antibodies against the SARS-CoV-2 viral spike protein 1 and receptor-binding domain after a first dose of a COVID-19 vaccine (ChAdOx1 or mRNA-1273), measured by enzyme-linked immunosorbent assay and applied spline-based generalized additive model regression analysis to predict NT50 converted to international units. RESULTS: After the first dose of ChAdOx1, multiple linear regression showed that age (p = 0.011) and cardiothoracic ratio (p = 0.002) were negatively associated with NT50. Older age (OR = 0.958, p = 0.052) and higher cardiothoracic ratio (OR < 0.001, p = 0.037) could predict negative humoral response (NT50 < 35.13 IU/mL). NT50 was lower in HD patients compared with healthy controls receiving ChAdOx1 (10.68 vs. 43.01 IU/m, p < 0.001) or mRNA-1273 (36.39 vs. 262.2 IU/mL, p < 0.001). ChAdOx1 elicited lower GMTs than mRNA-1273 in the HD cohort (10.68 vs. 36.39 IU/mL, p < 0.001) and in healthy controls (43.01 vs. 262.22 IU/mL, p < 0.001). CONCLUSION: High cardiothoracic ratio and old age could independently predict a decline in nAb titers in an HD cohort vaccinated with a single dose of ChAdOx1.

Adequacy of Hemodialysis Serves as an Independent Predictor of Humoral Response to ChAdOx1 Prime-Boost Vaccination in Hemodialysis Patients.

Background: Immune response assessed by the quantification of neutralizing antibodies (nAbs) and predictors associated with immunogenicity after the prime-boost ChAdOx1 (Oxford−AstraZeneca) COVID-19 vaccine in hemodialysis (HD) patients remains unclear. Methods: This prospective study enrolled 174 HD patients and 67 healthy subjects to evaluate antibodies against the spike protein 1 and receptor-binding domain of severe acute respiratory syndrome coronavirus type 2 after prime-booster vaccination, by using enzyme-linked immunosorbent assay and applied spline-based generalized additive model regression analysis to predict 50% neutralization titer (NT50). The correlation between HD parameters and NT50 was analyzed. Results: NT50 was lower in HD patients compared with healthy controls after the prime-boost dose (p < 0.001). The geometric mean titer ratios were higher in first-dose seronegative than in the seropositive subgroup in HD patients and healthy controls (6.96 vs. 2.36, p = 0.002, and 9.28 vs. 1.26, p = 0.011, respectively). After two doses of ChAdOx1, one-way ANOVA showed that Ca × P was positively associated with NT50 (p trend = 0.043) and multiple linear regression showed the similar results (p = 0.021). Kt/V (a quantification of dialysis adequacy) (OR = 20.295, p = 0.005) could independently predict seroconversion (NT50 ≥ 35.13 IU/mL). Conclusion: Adequacy of hemodialysis could independently predict seroconversion in HD subjects vaccinated with prime-boost doses of ChAdOx1.

Nutrition Assessment and Adverse Outcomes in Hospitalized Patients with Tuberculosis.

BACKGROUND: Malnutrition in patients with tuberculosis (TB) is associated with poor outcomes. This study assessed the validity of the patient-generated subjective global assessment (PG-SGA) in adult TB patients and examined the association of the PG-SGA score with adverse outcomes. METHODS: This is a retrospective chart review study compared with the well-nourished and malnourished TB patients. The nutritional status was determined using the PG-SGA for adult patients (n = 128). Clinical outcomes included liver injury and mortality. Adverse outcomes included hepatitis during anti-tuberculosis therapy. RESULTS: By comparing nutritional status using global assessment, well-nourished patients had a significantly higher body weight index (p = 0.002), a lower PG-SGA score (p < 0.001), and lower diabetic rate (p = 0.029). Malnourishment was a risk factor (p = 0.022) for liver injury and fatal outcomes (p < 0.001). A higher PG-SGA score was a risk factor for liver injury (p = 0.002) and an independent risk factor for fatal outcomes (p = 0.031). ROC analysis for outcome prediction showed that a PG-SGA score of 5.5 points yielded the most appropriate sensitivity (61.5%) and specificity (64.7%). CONCLUSION: Both global assessment and the total PG-SGA score were related to tuberculosis outcome and liver injury during anti-TB treatment.

Effective Preventive Strategies to Prevent Secondary Transmission of COVID-19 in Hemodialysis Unit: The First Month of Community Outbreak in Taiwan.

BACKGROUND: Dialyzed patients are vulnerable to coronavirus infection disease 2019 (COVID-19). The incidence and outcome of COVID-19 in hemodialysis (HD) patients in Taiwan remain unclear. A series of preventive measures were executed to combat COVID-19 transmission among HD patients. METHODS: We carried out a series of forward-looking and practical preventive strategies of COVID-19 control in our HD center. Incidences of COVID-19 of our HD unit were compared with those of national and local estimates from a community outbreak from 15 May to 30 June 2021. Prognostic factors associated with mortality were analyzed. RESULTS: The national incidence of COVID-19 was 0.062%; being highest in Taipei City (0.173%), followed by New Taipei City (0.161%) and Keelung (0.083%). The overall incidence in Keelung HD patients was 0.666%. One patient of our HD center contracted COVID-19 from the household; however, we have contained secondary transmission in our HD center by implementing strict preventive measures. The mortality rate of HD patients in Keelung was 66.6%. The median Ct value of HD patients was 17.53 (11.75-27.90) upon diagnosis. The deceased patients had a higher cardiac/thoracic ratio than alive (0.61 vs. 0.55, p = 0.036). CONCLUSIONS: Taking aggressive and proactive infection preventive measures impedes the secondary transmission of COVID-19 in HD facilities. COVID-19-associated mortality was high in HD patients, being the high cardiac-thoracic ratio, an important prognostic factor for clinical outcome of infected HD patients.

Colistin for pneumonia involving multidrug-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii complex.

OBJECTIVES: To investigate clinical and microbiological response, and 30-day mortality of pneumonia involving multidrug-resistant (MDR) Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) complex treated with colistin, and identify associated factors of these outcomes. METHODS: A retrospective study of 183 adult patients with colistin treatment for at least 7 days between January 2014 and October 2017. RESULTS: The mean age was 76.8 years, and mean Acute Physiology and Chronic Health Evaluation II score was 17.7. Eighteen (9.8%) and 128 (69.9%) patients had intravenous (IV) colistin alone and inhaled (IH) colistin alone, respectively. Thirty-seven patients had both IV and IH colistin, including 5 (2.7%) with concurrent, and 32 (17.5%) with non-concurrent use of IV and IH colistin. The 30-day mortality rate was 19.1% and 131 (71.6%) patients had clinical response. In the 175 patients with available data, 126 (72%) had microbiological eradication. The multivariate analyses revealed that IH colistin alone was an independent predictor for 30-day survival, clinical response, and microbiological eradication, and IV colistin alone was an independent predictor for clinical failure. Patients with IV colistin alone had a significantly higher nephrotoxicity rate than IH colistin alone (37.5% vs 6.1%, P = 0.001). Sub-group analysis of 52 patients with IV colistin for ≧ 4 days revealed that 14 (26.9%) patients had inappropriate dose, and inappropriate dose was an independent predictor for 30-day mortality. CONCLUSIONS: IH colistin provided good outcomes with few side effects, and appropriate dosing of IV colistin was important to avoid excess mortality.

Characteristics and factors influencing treatment outcome of renal and perinephric abscess--a 5-year experience at a tertiary teaching hospital in Taiwan.

BACKGROUND AND PURPOSE: Diagnosis of renal or perinephric abscess is still a challenge for physicians. This study investigated the effect of location and size of abscess and the time of diagnosis on treatment outcomes. METHODS: This retrospective analysis enrolled 159 adult patients with renal, perinephric or mixed-type (renal plus perinephric) abscess hospitalized between June 2001 and June 2006. The outcomes of these patients were classified into "poor" and "success" in order to elucidate associated risk factors. 106 patients had clear information of the timing of diagnosis and were categorized into "early" and "delayed" diagnosis groups, depending on whether the diagnosis was made within or after 5 days of admission. RESULTS: Compared with the early diagnosis group (n = 78), the delayed diagnosis group (n = 28) were older (59.9 +/- 15.9 vs 50.9 +/- 14.9 years, p=0.005) and had less costovertebral angle knocking pain (85.7% vs 51.3%, p=0.021), a higher rate of renal insufficiency (57.1% vs 15.4%, p<0.001) and hospital stay over 22 days (71.4% vs 24.4%, p<0.001). There was no significant difference between these two groups in clinical outcomes. Compared with renal abscess, both perinephric and mixed-type abscess had higher rates of larger abscess (>5 cm in diameter) [84.1% vs 25.6%, p<0.001; and 55.6% vs 25.6%, p=0.012, respectively] and lower rates of Escherichia coli infection (24.4% vs 59.4%, p<0.001; and 26.7% vs 59.4%, p=0.021, respectively). Among all culture-positive patients, the proportion of Klebsiella pneumoniae was 25.6%. Perinephric abscess had higher rates of percutaneous (56.3% vs 31.5%; p=0.005) and surgical drainage (29.2% vs 7.6%; p=0.001) than renal abscess. In multivariate analysis, age > or =65 years (p=0.006; odds ratio [OR], 7.008; 95% confidence interval [CI], 1.75-28.141), thrombocytopenia (p=0.002; OR [95% CI], 10.434 [2.344-46.444]), and abscess without drainage (p=0.001; OR [95% CI], 9.984 [2.640-37.758]) were independent factors for poor outcome (mortality or nephrectomy). CONCLUSION: Old age, renal insufficiency and lack of costovertebral angle knocking pain may contribute to delayed diagnosis of renal or perinephric abscess, and prolonged hospital stay. The location and size of abscess did not affect clinical outcome in this study, which might be due to adequate abscess drainage. K. pneumoniae is not uncommon in renal or perinephric abscess in Taiwan.

Clinical characteristics and treatment outcomes of vancomycin-resistant Enterococcus faecium bacteremia.

BACKGROUND: Vancomycin-resistant Enterococcus faecium (VRE-fm) bacteremia causes significant mortality in hospitalized patients. We sought to investigate clinical characteristics, treatment outcomes, and microbiological eradication associated with VRE-fm bacteremia. METHODS: A retrospective cohort study was conducted and included 210 adult patients admitted between January 1, 2011 and December 31, 2015. RESULTS: The mean Pitt bacteremia score was 4.7. ICU stay (48.6%) and mechanical ventilation (46.2%) were common. Diabetes mellitus was the most common concomitant disease (43.3%), followed by malignancies, including hematologic malignancies (14.3%) and solid cancers (28.1%). The 14-day and 28-day mortality rates were 37.1% and 50.5%, respectively. Linezolid or daptomycin treatment for at least 10 days and higher Pitt bacteremia scores were independently associated with 14-day and 28-day mortality. Longer treatment duration of linezolid or daptomycin predicted microbiological eradication independently. Daptomycin-treated patients tended to have higher 14-day and 28-day mortality, and lower microbial eradication rates (20.8% versus 8.7%; 40.6% versus 26.1%; 14.1% versus 26.1%; respectively) than linezolid-treated patients, and cumulative survival rates at 14 and 28 days tended to be lower in patients who received low-dose daptomycin (<10 mg/kg/day) than that in those who received linezolid and high-dose daptomycin (≥10 mg/kg/day); however, the differences were not statistically significant. CONCLUSION: Higher disease severity and inappropriate treatment were associated with increased mortality and longer treatment duration of linezolid or daptomycin was associated with microbial eradication for the patient with VRE-fm bacteremia.

Risk factors and outcomes of candidemia caused by Candida parapsilosis complex in a medical center in northern Taiwan.

To investigate the risk factors and outcomes associated with Candida parapsilosis candidemia, a retrospective study was conducted at a tertiary medical center in northern Taiwan. Patients with C. parapsilosis candidemia and corresponding controls with C. albicans candidemia were chosen and their demographics, comorbidities, risk factors, and clinical outcomes were reviewed. Antifungal susceptibility tests were performed using the Sensititre YeastOne colorimetric system. Matrix-assisted laser desorption ionization-time of flight mass spectrometry was used to classify the genomic species. Of the 270 candidemias found in 253 patients, C. albicans was the most common Candida species isolated (43.0%), followed by C. parapsilosis (22.6%), C. tropicalis (17.4%), and C. glabrata (10.0%). The 30-day mortality of C. parapsilosis candidemia was significantly lower than that of C. albicans candidemia (21.7% vs. 53.9%, P<0.001). C. parapsilosis was positively associated with antifungal agent exposure [OR 7.261 (95% CI, 1.603-32.879), P=0.010], but negatively associated with Candida colonization [OR 0.303 (95% CI, 0.123-0.745), P=0.009], and immunosuppressant use [OR 0.264 (95% CI, 0.099-0.705), P=0.008]. In-hospital mortality was associated with the Sequential Organ Failure Assessment Score [OR 1.255 (95% CI, 1.002-1.573), P=0.048]. The clinical outcomes did not differ across genomic species and in the minimum inhibitory concentrations of fluconazole.

Factors that affect sputum conversion and treatment outcome in patients with Mycobacterium avium-intracellulare complex pulmonary disease.

BACKGROUND AND PURPOSE: To investigate factors that might affect the sputum conversion and treatment outcome of Mycobacterium avium-intracellulare complex (MAC) pulmonary disease. METHODS: This retrospective study reviewed 46 patients diagnosed with MAC pulmonary disease at the Chang Gung Memorial Hospital at Linkou between July 1998 and February 2005. The diagnosis was based on the American Thoracic Society criteria for diagnosis of disease due to non-tuberculous mycobacteria of 1997. RESULTS: Of the 46 patients reviewed, 30 were men and 16 women, with a mean age of 64.39 years (range, 28-87 years). Thirty one patients had preexisting lung diseases, including history of pulmonary tuberculosis in 23 patients. Follow-up of sputum cultures could be traced in 28 patients, and sputum conversion was found in 17 patients. Of the 28 patients, 9 were treated with anti-MAC drugs for <5 months or with a regimen not containing at least 2 anti-MAC drugs. These treatment regimens were significantly associated with failure of sputum conversion to culture negativity (adjusted odds ratio [OR], 16.83; 95% confidence interval [CI], 1.16-245.06; p=0.039). Eleven of the remaining 19 patients were treated with an anti-MAC regimen containing clarithromycin for >5 months. However, there was no statistically significant association between sputum conversion and clarithromycin-containing anti-MAC regimens (OR, 0.42; 95% CI, 0.08-2.16; p=0.435). CONCLUSIONS: MAC pulmonary disease often occurs in the context of preexisting lung disease, especially pulmonary tuberculosis. Patients tend to be older. Inappropriate treatment might lead to failure of sputum conversion. Treatment with rational combination regimens for at least 5 months could be necessary for sputum conversion.

Risk factors and clinical significance of bacteremia caused by Pseudomonas aeruginosa resistant only to carbapenems.

BACKGROUND/PURPOSE: Carbapenem-resistant Pseudomonas aeruginosa infections have been a challenge and issue in hospital settings. However, the clinical impact of P. aeruginosa blood isolates resistant only to carbapenems has never been discussed previously. METHODS: To assess the risk factors and clinical significance of bacteremia caused by carbapenem resistance only P. aeruginosa (CROPA), a 6-year retrospective case-control study was conducted. The CROPA strains were defined as isolates susceptible to ciprofloxacin, antipseudomonal penicillins and cephalosporins, and aminoglycosides but resistant to one antipseudomonal carbapenem (imipenem or meropenem) or both. The controls were selected among patients with bacteremia due to P. aeruginosa susceptible to all above classes of antipseudomonal antibiotics, which was defined as all-susceptible P. aeruginosa. RESULTS: Twenty-five patients had at least one blood culture positive for CROPA, and 50 controls had all-susceptible P. aeruginosa bacteremia. CROPA bacteremia had a high 30-day mortality rate (72.0%), as compared to 26.0% for the controls (p < 0.001). Through multivariate analysis, carbapenem exposure was the only risk factor for developing CROPA bacteremia (p = 0.002). A comparison between the surviving and deceased patients with CROPA bacteremia showed that nine (50%) of those who died, but none of the survivors, received carbapenems as the initial empirical therapy (p = 0.027). CONCLUSION: Carbapenem exposure was associated with emergence of CROPA infections. Repeated carbapenem use in such patients might increase rates of inappropriate initial empirical treatment and mortality. Prudent carbapenem use is important to reduce the emergence of CROPA.

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.

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

BACKGROUND: Multidrug-resistant (MDR) Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) complex has become an important cause of nosocomial pneumonia. Sulbactam is a ß-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 characteristics and risk factors for mortality in cefepime-resistant Pseudomonas aeruginosa bacteremia.

BACKGROUND: To identify the clinical characteristics and risk factors for mortality of patients with cefepime-resistant Pseudomonas aeruginosa (FRPa) bacteremia. METHODS: This retrospective study analyzed adult patients with FRPa bacteremia hospitalized between January 2006 and December 2011. RESULTS: Seventy eight patients (46 male, 32 female; mean age: 72.2 ± 14.1 years) were included. Of them, 46 (59.0%) had ventilator use and 45 (57.7%) had intensive care unit stay. All the bacteremia episodes were health-care associated or hospital acquired, and 55.1% of FRPa blood isolates were multidrug resistant. The sources of bacteremia were identified in 42 patients (53.8%), with pneumonia being the most common one (28/42; 66.7%). The mean interval between admission and the sample date of the first FRPa-positive blood culture was 45.8 ± 52.6 days. The mean Pittsburgh bacteremia score was 5.0 ± 3.4. The 15-day and 30-day mortality rates were 50.0% and 65.4%, respectively. Patients (41; 52.6%) on appropriate antibiotic therapy within 72 hours of the first FRPa-positive blood culture had a higher 30-day survival rate than those without (48.8% vs. 18.9%, p = 0.011 by log-rank test). Multivariate analyses revealed that a higher Pittsburgh bacteremia score was an independent risk factor for either 15-day (p = 0.002) or 30-day mortality (p = 0.010), and appropriate antibiotic therapy within 72 hours was an independent protecting factor for either 15-day (p = 0.049) or 30-day mortality (p = 0.017). CONCLUSION: FRPa bacteremia had a high mortality rate. The disease severity and appropriate antimicrobial therapy within 72 hours of positive blood culture were related to the patients' outcome.

Derivation of a clinical prediction rule for bloodstream infection mortality of patients visiting the emergency department based on predisposition, infection, response, and organ dysfunction concept.

BACKGROUND/PURPOSE: Bloodstream infection (BSI) is a serious infection with a high mortality. We aimed to construct a predictive scoring system to stratify the severity of patients with BSI visiting the emergency department (ED). METHODS: We conducted a retrospective cohort study consisting of patients who visited the ED of a tertiary hospital with documented BSI in 2010. The potential predictors of mortality were obtained via chart review. Multivariate logistic regression was utilized to identify predictors of mortality. Penalized maximum likelihood estimation (PMLE) was applied for score development. RESULTS: There were 1063 patients with bacteremia included, with an overall 28-day mortality rate of 13.2% (n = 140). In multiple logistic regression with penalization, the independent predictors of death were "predisposition": malignancy (ß-coefficient, 0.65; +2 points); "infection": Staphylococcus aureus (S. aureus) bacteremia (0.69; +2 points), pneumonia (1.32; +4 points), and bacteremia with an unknown focus (0.70; +2 points); "response": body temperature <36 °C (1.17; +3 points), band form >5% (1.00; +3 points), and red blood cell distribution width (RDW) >15% (0.63; +2 points); and "organ dysfunction": pulse oximeter oxygen saturation <90% (0.72; +2 points) and creatinine >2 mg/dL (0.69; +2 points). The area under receiver operating characteristic curve (AUROC) for the model was 0.881 [95% confidence interval (CI), 0.848-0.913], with a better performance than the Pitt bacteremia score (AUROC: 0.750; 95% CI 0.699-0.800, p < 0.001). The patients were stratified into four risk groups: (1) low, 0-3 points, mortality rate: 1.5%; (2) moderate, 4-6 points, mortality rate: 10.5%; (3) high, 7-8 points, mortality rate: 28.6%; and (4) very high, ≥ 9 points, mortality rate: 65.5%. CONCLUSION: The new scoring system for bacteremia could facilitate the prediction of the risk of 28-day mortality for patients visiting the ED with BSI.

Synergy of imipenem/colistin methanesulfonate combinations against imipenem-nonsusceptible multidrug-resistant Acinetobacter baumannii.

BACKGROUND: The optimal combination ratio of imipenem to colistin methanesulfonate (CMS) against imipenem-nonsusceptible multidrug-resistant Acinetobacter baumannii (INS-MDRAB) has not been determined in previous studies. To provide an alternative therapeutic option for clinical INS-MDRAB isolates, we investigated whether clinically achievable serum concentrations of CMS in combination with imipenem enhance the in vitro activity of imipenem against the INS-MDRAB isolates. MATERIALS AND METHODS: Fifty-nine INS-MDRAB isolates with imipenem minimal inhibitory concentration (MIC) values of ≥8 mg/L were selected randomly from the Clinical Microbiology Laboratory at a university-affiliated medical center between July 1998 and May 2005. The in vitro activity of imipenem among these 59 clinical isolates was explored via serial two-fold dilutions containing a range of imipenem concentration from 0.125 mg/L to 256 mg/L, in combination with two fixed CMS concentrations at 0.5 mg/L and 1 mg/L. Genotype classification was performed using the pulsed-field gel electrophoresis method and infrequent-restriction-site polymerase chain reaction. RESULTS: A significant reversal of imipenem resistance (i.e., MICs ≤ 4 mg/L) was observed in 34 (57.6%) isolates and 44 (74.6%) isolates with the tests of CMS concentrations at 0.5 mg/L and 1 mg/L, respectively (p = 0.041). Genotype 1 was predominant (43 isolates, 72.9%) with imipenem resistance reversal rates of 51.2% and 79.1% (p = 0.004) in the tests of CMS at 0.5 mg/L and 1 mg/L, respectively. CONCLUSION: The synergy of imipenem/CMS against INS-MDRAB was significantly better for the CMS concentration at 1 mg/L than that at 0.5 mg/L, especially in our predominant clone. Our results provided insightful information for treating INS-MDRAB infections in clinical practice.

Serratia marcescens meningitis: epidemiology, prognostic factors and treatment outcomes.

BACKGROUND/PURPOSE: Serratia marcescens is a rare pathogen of central nervous system infections. This study was to investigate the epidemiology, prognostic factors, and treatment outcomes of S. marcescens meningitis. METHODS: This retrospective analysis included 33 patients with culture-proven S. marcescens meningitis hospitalized between January 2000 and June 2011. RESULTS: Of the 33 patients enrolled, only one did not receive neurosurgery before the onset of S. marcescens meningitis. Patients with S. marcescens meningitis had higher ratios of brain solid tumors (54.5%) and neurosurgery (97.0%) with a mortality rate of 15.2%. The mean interval between the first neurosurgical procedure and the diagnosis of meningitis was 17.1 days (range, 4-51 days). Only one third-generation cephalosporin-resistant S. marcescens isolate was recovered from the patients' cerebrospinal fluid (CSF) specimens. Compared with the favorable outcome group (n = 20), the unfavorable outcome group (n = 13) had a higher percentage of brain solid tumors, more intensive care unit stays, and higher Sequential Organ Failure Assessment score, CSF lactate and serum C-reactive protein concentrations at diagnosis of meningitis. Under the multiple regression analysis, CSF lactate concentration ≥2-fold the upper limit of normal (ULN) was independently associated with unfavorable outcomes (odds ratio, 7.20; 95% confidence interval, 1.08-47.96; p = 0.041). CONCLUSION: S. marcescens meningitis is highly associated with neurosurgical procedures for brain solid tumors. CSF lactate concentration ≥2x ULN may predict an unfavorable outcome. Its mortality is not high and empiric treatment with parenteral third-generation cephalosporins may have a satisfactory clinical response.