Chia-Jui Yang

Excess Mortality Associated With Colistin-Tigecycline Compared With Colistin-Carbapenem Combination Therapy for Extensively Drug-Resistant Acinetobacter baumannii Bacteremia: A Multicenter Prospective Observational Study.

Objectives:Since few therapeutic options exist for extensively drug resistant Acinetobacter baumannii, an emerging threat in ICUs worldwide, and comparative prospective studies of colistin-based combination therapies are lacking, our objective was to compare the outcomes of patients with extensively drug-resistant A. baumannii bacteremia, treated with colistin-carbapenem and colistin-tigecycline combinations. Design:Prospective, observational, multicenter study. Setting, Patients, and Interventions:Adults with extensively drug-resistant A. baumannii bacteremia were prospectively followed from 2010 to 2013 at three hospitals in Taiwan. Extensively drug-resistant A. baumannii was defined as A. baumannii (genospecies 2) nonsusceptible to all drug classes except for colistin and tigecycline, and standard combination therapy as use of parenteral colistin-carbapenem or colistin-tigecycline for at least 48 hours after onset of bacteremia. Measurements and Main Results:Primary outcome measure was 14-day mortality. Of the 176 episodes of extensively drug-resistant A. baumannii bacteremia evaluated, 55 patients with a median (interquartile range) age of 62 years (44–79 yr) and Sequential Organ Failure Assessment score of 9 (5–13) points received standard combination therapy: colistin-tigecycline in 29 patients and colistin-carbapenem in 26. Crude 14-day and in-hospital mortality rates for patients receiving colistin-tigecycline versus patients receiving colistin-carbapenem were 35% versus 15% (p = 0.105) and 69% versus 50% (p = 0.152), respectively. Breakthrough extensively drug-resistant A. baumannii bacteremia under steady state concentrations of combination therapy for colistin-tigecycline group was 18% and for colistin-carbapenem group was 0% (p = 0.059). Eleven patients (20.0%) developed nephrotoxicity. After adjusting for age, sex, comorbidity, initial disease severity, loading colistin dose, polymicrobial infection, and primary infection site, excess 14-day mortality was associated with the use of colistin-tigecycline in the subgroup with tigecycline minimum inhibitory concentration greater than 2 mg/L compared with the use of colistin-carbapenem (hazard ratio, 6.93; 95% CI, 1.61–29.78; p = 0.009). Conclusions:Increased 14-day mortality was associated with colistin-tigecycline therapy given tigecycline minimum inhibitory concentration greater than 2 mg/L compared with colistin-carbapenem therapy for extensively drug-resistant A. baumannii bacteremia.

Evaluation of Macrolide Resistance and Enhanced Molecular Typing of Treponema pallidum in Patients with Syphilis in Taiwan: a Prospective Multicenter Study

ABSTRACT Studies of macrolide resistance mutations and molecular typing using the newly proposed enhanced typing system for Treponema pallidum isolates obtained from HIV-infected patients in the Asia-Pacific region are scarce. Between September 2009 and December 2011, we conducted a survey to detect T. pallidum using a PCR assay using clinical specimens from patients with syphilis at six major designated hospitals for HIV care in Taiwan. The T. pallidum strains were genotyped by following the enhanced molecular typing methodology, which analyzed the number of 60-bp repeats in the acidic repeat protein (arp) gene, T. pallidum repeat (tpr) polymorphism, and the sequence of base pairs 131 to 215 in the tp0548 open reading frame of T. pallidum. Detection of A2058G and A2059G point mutations in the T. pallidum 23S rRNA was performed with the use of restriction fragment length polymorphism (RFLP). During the 2-year study period, 211 clinical specimens were obtained from 136 patients with syphilis. T. pallidum DNA was isolated from 105 (49.8%) of the specimens, with swab specimens obtained from chancres having the highest yield rate (63.2%), followed by plasma (49.4%), serum (35.7%), and cerebrospinal fluid or vitreous fluid (18.2%) specimens. Among the 40 fully typed specimens, 11 subtypes of T. pallidum were identified. Subtype 14f/f (18 isolates) was the most common isolates, followed by 14f/c (3), 14b/c (3), and 14k/f (3). Among the isolates examined for macrolide resistance, none had the A2058G or A2059G mutation. In conclusion, we found that type 14 f/f was the most common T. pallidum strain in this multicenter study on syphilis in Taiwan and that none of the isolates exhibited 23S rRNA mutations causing resistance to macrolides.

Jarisch-Herxheimer Reaction after Penicillin Therapy among Patients with Syphilis in the Era of the HIV Infection Epidemic: Incidence and Risk Factors

The incidence of and risk factors for Jarisch-Herxheimer (JH) reaction were investigated prospectively among 240 human immunodeficiency virus (HIV)-infected and 115 HIV-uninfected patients with syphilis who received penicillin treatment. The overall rate of JH reaction was 31.5% (34.6% in HIV-infected patients and 25.2% in HIV-uninfected patients). In multivariate analysis, risk factors for JH reaction included high rapid plasma reagin (RPR) titers (per log(2) RPR increase, risk ratio [RR], 1.19; 95% confidence interval [CI], 1.04-1.37), early syphilis (RR, 8.59; 95% CI, 4.75-15.56), and prior penicillin treatment (RR, 0.39; 95% CI, 0.20-0.78).

Bacteremia caused by Pantoea agglomerans at a medical center in Taiwan, 2000–2010

BACKGROUND/PURPOSE There are only three case reports of adult patients with spontaneous Pantoea agglomerans bacteremia in the English literature. The aim of this study was to investigate clinical and microbiologic characteristics patients of P agglomerans bacteremia. METHODS We studied all adult patients with P agglomerans bacteremia at a medical center from 2000 to 2010. The isolates were identified using two commercial identification systems. RESULTS Of the 18 patients identified, 72% (n = 13) had active gastroesophageal disease treated with antacids. Two-thirds of patients had indwelling central lines and advanced cancers. None of the removed catheter tips yielded P agglomerans and line persistence was not associated with adverse outcomes. Initial disease severity was low, hypotension was uncommon and no patient died of bacteremia. Recurrence of bacteremia occurred in one patient with deep-seated infection. 16srRNA gene sequencing identified only half of the isolates as P agglomerans. The remaining nine isolates were Enterobacter species for six, Pantoea ananatis for two, and Exiguobacterium profundum for one. There were no significant differences between the characteristics of the subgroup molecularly identified as P agglomernas and the overall group characteristics. Eleven (61%) of the 18 isolates were susceptible to cefazolin, six (33%) susceptible to fosfomycin (MIC ≤ 64 mg/ml). Two isolates had colistin MICs ≥ 4 mg/ml. CONCLUSION Bacteremia caused by P agglomerans is associated with gastroesophageal reflux disease and receipt of antacids. 16srRNA gene sequencing should not be used as the sole basis for its identification and we have highlighted the need for another molecular-based technique to conclusively characterize P agglomerans.

Clinical characteristics and outcomes of patients with Burkholderia cepacia bacteremia in an intensive care unit

The purpose of this study was to investigate a cohort of patients with Burkholderia cepacia bacteremia in the intensive care unit (ICU) at our institution. A large outbreak of B. cepacia bacteremia involving 95 patients lasted for 4 years in an ICU in northern Taiwan. The clinical characteristics and antimicrobial treatment responses of these patients were analyzed. Minimal inhibitory concentrations were determined and pulse-field gel electrophoresis was performed for the 73 available isolates. Overall, the in-hospital mortality rate was 53.8% and the 14-day mortality rate was 16.8%. Most patients (95.6%) had several underlying diseases and all but 1 patient had tracheal intubation. Malignancy (37.5% versus 13.9%, P = 0.02) and higher Sequential Organ Failure Assessment (SOFA) scores at the onset of bacteremia (11.9 ± 4.7 versus 7.9 ± 3.6, P < 0.001) were significant risk factors for 14-day mortality. In contrast, treatment with ceftazidime (76.0% versus 43.7%, P = 0.02) and diabetes (51.9% versus 13.8%, P = 0.01) were associated with decreased mortality. In the multivariate analysis, malignancy and higher SOFA score were significant risk factors for mortality [odds ratio (OR) 12.45, 95% confidence interval (CI) 2.35-65.94; OR 1.20, 95% CI 1.00-1.45, respectively]. Meropenem, ceftazidime, and piperacillin-tazobactam were the most active agents (susceptible rate 100%, 97.3%, and 97.3%, respectively). Pulsed-field gel electrophoresis results indicated 49 of the 73 isolates could be classified as outbreak-related strains. There was no significant difference in the clinical characteristics and outcomes of patients with bacteremia due to outbreak-related and non-outbreak-related strains. In conclusion, malignancy and a higher SOFA score at onset of bacteremia predicted increased mortality, but the clinical presentation and outcome of patients with outbreak and non-outbreak strains were similar.

Acute psychosis related to use of trimethoprim/sulfamethoxazole in the treatment of HIV-infected patients with Pneumocystis jirovecii pneumonia: a multicentre, retrospective study

OBJECTIVES A recent study reported that trimethoprim/sulfamethoxazole caused acute psychosis in four renal transplant patients with Pneumocystis jirovecii pneumonia. We aimed to investigate the incidence of and factors associated with trimethoprim/sulfamethoxazole-related acute psychosis in HIV-infected patients with P. jirovecii pneumonia. METHODS We reviewed the medical records of HIV-infected patients who presented with P. jirovecii pneumonia and received trimethoprim/sulfamethoxazole at six major hospitals in Taiwan from July 2009 to May 2011. Acute psychosis was defined as the occurrence of hallucinations or delusions following the initiation of trimethoprim/sulfamethoxazole during hospitalization. RESULTS During the study period, 135 patients receiving trimethoprim/sulfamethoxazole for P. jirovecii pneumonia were enrolled and 16 (11.9%; 95% CI, 6.3%-17.4%) developed acute psychosis after a median duration of 5 days of trimethoprim/sulfamethoxazole treatment (range, 3-11 days). The incidence increased from 0% (0/16) in patients who received a daily trimethoprim dose of ≤12 mg/kg to 23.5% (4/17) in those who received a daily trimethoprim dose of >18 mg/kg. In multivariate logistic regression analysis, a higher daily dose of trimethoprim/sulfamethoxazole (OR, per 1 mg increase of trimethoprim, 1.40; 95% CI, 1.12-1.76; P = 0.0035) and use of adjunctive steroids (OR, 4.43; 95% CI, 1.14-17.15; P = 0.031) were associated with acute psychosis. CONCLUSIONS In this case series, 11.9% of HIV-infected patients developed acute psychosis while receiving trimethoprim/sulfamethoxazole for P. jirovecii pneumonia. While the study was limited by its retrospective design, the risk appeared to increase with increasing daily dose of trimethoprim/sulfamethoxazole in those vulnerable patients with multiple risks for acute psychosis.

Multicenter Study of Trimethoprim/Sulfamethoxazole-Related Hepatotoxicity: Incidence and Associated Factors among HIV-Infected Patients Treated for Pneumocystis jirovecii Pneumonia

The incidence of hepatotoxicity related to trimethoprim/sulfamethoxazole (TMP/SMX) administered at a therapeutic dose may vary among study populations of different ethnicities and hepatotoxic metabolites of TMP/SMX may be decreased by drug-drug interaction with fluconazole. We aimed to investigate the incidence of hepatotoxicity and the role of concomitant use of fluconazole in HIV-infected patients receiving TMP/SMX for Pneumocystis jirovecii pneumonia. We reviewed medical records to collect clinical characteristics and laboratory data of HIV-infected patients who received TMP/SMX for treatment of P. jirovecii pneumonia at 6 hospitals around Taiwan between September 2009 and February 2013. Hepatotoxicity was defined as 2-fold or greater increase of aminotransferase or total bilirubin level from baselines. Roussel UCLAF Causality Assessment Method (RUCAM) was used to analyze the causality of drug-induced liver injuries. NAT1 and NAT2 acetylator types were determined with the use of polymerase-chain-reaction (PCR) restriction fragment length polymorphism to differentiate common single-nucleotide polymorphisms (SNPs) predictive of the acetylator phenotypes in a subgroup of patients. During the study period, 286 courses of TMP/SMX treatment administered to 284 patients were analyzed. One hundred and fifty-two patients (53.1%) developed hepatotoxicity, and TMP/SMX was considered causative in 47 (16.4%) who had a RUCAM score of 6 or greater. In multivariate analysis, concomitant use of fluconazole for candidiasis was the only factor associated with reduced risk for hepatotoxicity (adjusted odds ratio, 0.372; 95% confidence interval, 0.145–0.957), while serostatus of hepatitis B or C virus, NAT1 and NAT2 acetylator types, or receipt of combination antiretroviral therapy was not. The incidence of hepatotoxicity decreased with an increasing daily dose of fluconazole up to 4.0 mg/kg. We conclude that the incidence of TMP/SMX-related hepatotoxicity was 16.4% in HIV-infected Taiwanese patients who received TMP/SMX for pneumocystosis. Concomitant use of fluconazole was associated with decreased risk for TMP/SMX-related hepatotoxicity.

Patients Infected with CRF07_BC Have Significantly Lower Viral Loads than Patients with HIV-1 Subtype B: Mechanism and Impact on Disease Progression

The circulating recombinant form (CRF) 07_BC is the most prevalent HIV-1 strain among injection drug users (IDUs) in Taiwan. It contains a 7 amino-acid deletion in its p6gag. We conducted a cohort study to compare viral loads and CD4 cell count changes between patients infected with subtype B and CRF07_BC and to elucidate its mechanism. Twenty-one patients infected with CRF07_BC and 59 patients with subtype B were selected from a cohort of 667 HIV-1/AIDS patients whom have been followed up for 3 years. Generalized estimated equation was used to analyze their clinical data and the results showed that patients infected with CRF07_BC had significantly lower viral loads (about 58,000 copies per ml less) than patients with subtype B infection (p = 0.002). The replicative capacity of nine CRF07_BC and four subtype B isolates were compared and the results showed that the former had significantly lower replicative capacity than the latter although all of them were CCR5- tropic and non-syncytium inducing viruses. An HIV-1-NL4-3 mutant virus which contains a 7 amino-acid deletion in p6gag (designated as 7d virus) was generated and its live cycle was investigated. The results showed that 7d virus had significantly lower replication capacity, poorer protease-mediated processing and viral proteins production. Electron microscopic examination of cells infected with wild-type or 7d virus demonstrated that the 7d virus had poorer and slower viral maturation processes: more viruses attached to the cell membrane and higher proportion of immature virions outside the cells. The interaction between p6gag and Alix protein was less efficient in cells infected with 7d virus. In conclusion, patients infected with CRF07_BC had significantly lower viral loads than patients infected with subtype B and it may due to the deletion of 7 amino acids which overlaps with Alix protein-binding domain of the p6gag.

Hepatitis B Virus (HBV) Coinfection Accelerates Immunologic Progression in Patients With Primary HIV Infection in an Area of Hyperendemicity for HBV Infection

TO THE EDITOR—We read with interest the article by Chun et al [1]. They demonstrated the negative impact of chronic hepatitis B virus (HBV) coinfection on HIV progression by increasing the risk for AIDS-defining illness and death (adjusted hazard ratio [aHR], 1.80; 95% confidence interval [CI], 1.20–2.69) among 2352 HIV-infected active duty military personnel and other beneficiaries in whom the HIV diagnosis seroconversion window was estimated at ≤3 years and the prevalence of chronic HBV infection was 3%. The negative impact, we believe, would be also observed by using immunologic progression as a study end point in patients with primary HIV infection in areas of higher endemicity for HBV infection. Between January 1997 and December 2011, we conducted a prospective observational study in patients with primary HIV infection at 2 major medical centers for HIV care in Taiwan where HIV care, including combination antiretroviral therapy (cART) and HIV monitoring, is provided free of charge. In Taiwan, most HBV infections occurred in the perinatal period and childhood, and the prevalence of chronic HBV infection was 18%–20% among adults born before nationwide HBV vaccination was implemented in 1986 [2]. We identified patients aged ≥18 years who did not start antiretroviral treatment during the first 3 months after the diagnosis of primary HIV infection. Primary HIV infection was defined as an interval of ≤6 months between negative and positive HIV serologic tests with enzyme-linked immunosorbent assay; an incomplete Western blot finding; or a negative HIV serologic test in the presence of HIV viremia demonstrated by real-time polymerase chain reaction (PCR). Immunologic progression was defined as the occurrence of a CD4 count <350 cells/μL ≥3 months after diagnosis of primary HIV infection. We performed HIV-1 V3 genotyping testing to determine the HIV tropism of the HIV-1 strains in the study subjects [3]. In brief, viral RNA was extracted using the QIAamp Viral RNA Mini Kit (Qiagen). The purified RNA was subjected to 1-step reverse-transcription PCR. The partial HIV-1 env gene containing the V3 fragment was PCR amplified, sequenced, and analyzed. Populationbased nucleotide sequence analysis of the PCR fragments was conducted by using an automatic sequencer (3100 Avent Genetic Analyzer; ABI). The geno2pheno

Listeriosis, Taiwan, 1996–2008

During 1996–2008, a total of 48 patients with listeriosis were identified at a Taiwan hospital. Average annual incidence increased from 0.029 to 0.118 cases per 1,000 admissions before and after January 2005. Serotype 1/2b predominated; serotype 4b emerged since 2004. Food monitoring and disease surveillance systems could help control listeriosis in Taiwan.