Genomic Insight into the Spread of Meropenem-Resistant Streptococcus pneumoniae Spain23F-ST81, Taiwan.

Incidence of invasive pneumococcal disease caused by antimicrobial-resistant Streptococcus pneumoniae types not included in pneumococcal conjugate vaccines has increased, including a penicillin- and meropenem-resistant serotype 15A-ST63 clone in Japan. During 2013-2017, we collected 206 invasive pneumococcal isolates in Taiwan for penicillin and meropenem susceptibility testing. We found serotypes 15B/C-ST83 and 15A-ST63 were the most prevalent penicillin- and meropenem-resistant clones. A transformation study confirmed that penicillin-binding protein (PBP) 2b was the primary meropenem resistance determinant, and PBP1a was essential for high-level resistance. The rate of serotype 15B/C-ST83 increased during the study. All 15B/C-ST83 isolates showed an ermB macrolide resistance genotype. Prediction analysis of recombination sites revealed 12 recombination regions in 15B/C-ST83 compared with the S. pneumoniae Spain23F-ST81 genome. Pneumococcal clones rapidly recombine to acquire survival advantages and undergo local expansion under the selective pressure exerted by vaccines and antimicrobial drugs. The spread of 15B/C-ST83 is alarming for countries with high antimicrobial pressure.

Diagnostic performance of the Sofia® influenza A+B fluorescent immunoassay in adult outpatients in Northern Taiwan.

To evaluate the diagnostic performance of the Sofia influenza A+B fluorescent immunoassay (Sofia FIA), we performed a prospective study at the Chang Gung Memorial Hospital in Taiwan from January 2012 to December 2013. Patients who presented at out-patient clinics or the emergency department with influenza-like illness were included. Upper respiratory tract specimens were collected from oropharynx or nasopharynx. Performance of the Sofia FIA was compared to that of the Formosa One Sure Flu A/B Rapid Test. A Real-time reverse transcriptase-polymerase chain reaction assay (RT-PCR) and/or virus culture were used as reference standards. Of the 109 enrolled patients, the sensitivity, specificity, positive, and negative predictive values of the Sofia FIA to detect influenza A virus were 82%, 89%, 77%, and 89%, respectively. These parameters were 100% when the samples were from nasopharynx. The positive predictive value for influenza B virus detection was 29%. The sensitivity of the Sofia FIA for detection of influenza A virus was 93% between days 2 and 4 after onset of symptoms. For specimens with low viral loads (RT-PCR cycle threshold between 30 and 34.9), the sensitivity of The Sofia FIA was 83% (10/12). The Sofia FIA performed effectively in detecting influenza A virus infection. With nasopharyngeal samples, the performance was comparable to RT-PCR. Although influenza viral load typically decreases with time, the Sofia FIA was sensitive enough to identify influenza infecting patients presenting after several days of illness. However, a high false positive rate limits the assay's usefulness to identify influenza B virus infection.

Development of carbapenem resistance in Pseudomonas aeruginosa is associated with OprD polymorphisms, particularly the amino acid substitution at codon 170.

Objectives: Pan-susceptible Pseudomonas aeruginosa (PSPA) clinical isolates carrying an OprD with loop 7 shortening (the group-1A allele) were found to rapidly develop carbapenem resistance under continuous selection pressure. We further studied whether OprD polymorphisms are associated with the potential to develop carbapenem resistance. Methods: OprD amino acid sequences of 126 PSPA clinical isolates were analysed to determine their STs using P. aeruginosa strain PAO1 as the control strain. Site-directed mutagenesis was performed in PAO1 to generate polymorphisms of interest. A disc diffusion method was used to select carbapenem-resistant variants from the mutant strains. Expression levels of oprD were determined by quantitative RT-PCR. MICs of carbapenems were determined by Etest. Results: Forty-eight (38.1%) of the tested isolates carried the group-1A allele. Another two major STs, C1 and C2, both of which harboured an F170L polymorphism, were found in 21 (16.7%) and 39 (31.0%) isolates, respectively. The PAO1 type was also found in 14 (11.1%) isolates. Under continuous selective pressure, isolates of most STs developed carbapenem resistance at different numbers of passaging events; only those belonging to the PAO1 type remained susceptible. However, PAO1 mutants carrying either the oprD group-1A allele or the OprD-F170L polymorphism were able to develop carbapenem resistance. Reduced oprD expression triggered by continuous imipenem challenge was found in PAO1 mutants, but not in the PAO1 WT strain. Conclusions: OprD polymorphisms, particularly the F170L substitution and the specific shortening in loop 7, appear to determine the potential for P. aeruginosa to develop carbapenem resistance.

Antimicrobial resistance in Mycobacterium abscessus complex isolated from patients with skin and soft tissue infections at a tertiary teaching hospital in Taiwan.

Background: Mycobacterium abscessus complex (MABC) is the most common non-tuberculous mycobacterium that causes complicated skin and soft tissue infections (cSSTIs). The selection of antimycobacterial agents for successful treatment of such infections is a critical issue. Objectives: To investigate the antimicrobial susceptibility patterns of MABC isolates from skin and soft tissue to a variety of antimycobacterial agents. Methods: Sixty-seven MABC isolates were collected and partial gene sequencing of secA1, rpoB and hsp65 was used to classify them into three subspecies: M. abscessus subsp. abscessus (MAB), M. abscessus subsp. massiliense (MMA) and M. abscessus subsp. bolletii (MBO). The MICs of 11 antimycobacterial agents for these 67 isolates were determined using a broth microdilution method and commercial Sensititre RAPMYCOI MIC plates, as recommended by CLSI. Results: In total, 28 MAB, 38 MMA and 1 MBO were isolated from patients with cSSTIs at our hospital. Most MABC strains were resistant to ciprofloxacin, doxycycline, imipenem, linezolid, minocycline, moxifloxacin and trimethoprim/sulfamethoxazole. In addition, most MABC strains were intermediately susceptible or resistant to cefoxitin. Eighteen of the 28 MABs and 1 MBO isolate harboured the T28 polymorphism in the erm(41) gene. Two of the 38 MMA isolates had an rrl A2059G point mutation. Most of the MABC strains were susceptible to amikacin and tigecycline. Conclusions: In Taiwan, amikacin, clarithromycin and tigecycline have good activity against MMA and MAB erm(41) C28 sequevar isolates, whereas amikacin and tigecycline, rather than clarithromycin, have good activity against both MBO and MAB erm(41) T28 sequevar isolates. Clinical trials are warranted to correlate these data with clinical outcomes.

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.

KPC-2-encoding plasmids from Escherichia coli and Klebsiella pneumoniae in Taiwan.

OBJECTIVES: Two plasmids carrying bla(KPC-2) isolated from carbapenem-resistant Escherichia coli (CR-EC) and carbapenem-resistant Klebsiella pneumoniae (CR-KP), respectively, were completely sequenced. The CR-KP strain was selected from an outbreak in 2012, and the CR-EC strain was the first blaKPC-2-carrying E. coli identified in the same carbapenem resistance monitoring programme in Taiwan. METHODS: Antimicrobial susceptibility tests, multilocus sequence typing (MLST) and the conjugal transfer of plasmids were performed. Complete sequencing of the plasmids was performed using a shotgun approach. RESULTS: The CR-EC and CR-KP strains in this study were determined to be ST410 and ST11, respectively, by MLST. From CR-EC, we identified a 145 kb conjugative plasmid that carries bla(KPC-2), bla(CMY-2), bla(CTX-M-3) and bla(TEM-1). The plasmid is a chimera composed of three regions related to IncI, IncN and RepFIC replicons. From CR-KP, we identified an 86.5 kb plasmid, pKPC-LK30, which carries bla(KPC-2) and bla(SHV-11). The plasmid is very similar to two bla(KPC-2)-carrying IncFII(K) plasmids, but lacks one of the replication origins and cannot conjugate. CONCLUSIONS: The differences in cross-species transferability of the two plasmids can be explained by genetic differences between their backbones and could have resulted in the confined bla(KPC-2)-carrying CR-KP outbreak in Taiwan. Plasmid pKPC-LKEc is the first bla(KPC-2)-carrying plasmid identified from CR-EC in Taiwan. With relatively high transferability it should be closely monitored.

Genetic variants associated with phenytoin-related severe cutaneous adverse reactions.

IMPORTANCE: The antiepileptic drug phenytoin can cause cutaneous adverse reactions, ranging from maculopapular exanthema to severe cutaneous adverse reactions, which include drug reactions with eosinophilia and systemic symptoms, Stevens-Johnson syndrome, and toxic epidermal necrolysis. The pharmacogenomic basis of phenytoin-related severe cutaneous adverse reactions remains unknown. OBJECTIVE: To investigate the genetic factors associated with phenytoin-related severe cutaneous adverse reactions. DESIGN, SETTING, AND PARTICIPANTS: Case-control study conducted in 2002-2014 among 105 cases with phenytoin-related severe cutaneous adverse reactions (n=61 Stevens-Johnson syndrome/toxic epidermal necrolysis and n=44 drug reactions with eosinophilia and systemic symptoms), 78 cases with maculopapular exanthema, 130 phenytoin-tolerant control participants, and 3655 population controls from Taiwan, Japan, and Malaysia. A genome-wide association study (GWAS), direct sequencing of the associated loci, and replication analysis were conducted using the samples from Taiwan. The initial GWAS included samples of 60 cases with phenytoin-related severe cutaneous adverse reactions and 412 population controls from Taiwan. The results were validated in (1) 30 cases with severe cutaneous adverse reactions and 130 phenytoin-tolerant controls from Taiwan, (2) 9 patients with Stevens-Johnson syndrome/toxic epidermal necrolysis and 2869 population controls from Japan, and (3) 6 cases and 374 population controls from Malaysia. MAIN OUTCOMES AND MEASURES: Specific genetic factors associated with phenytoin-related severe cutaneous adverse reactions. RESULTS: The GWAS discovered a cluster of 16 single-nucleotide polymorphisms in CYP2C genes at 10q23.33 that reached genome-wide significance. Direct sequencing of CYP2C identified missense variant rs1057910 (CYP2C9*3) that showed significant association with phenytoin-related severe cutaneous adverse reactions (odds ratio, 12; 95% CI, 6.6-20; P=1.1 × 10(-17)). The statistically significant association between CYP2C9*3 and phenytoin-related severe cutaneous adverse reactions was observed in additional samples from Taiwan, Japan, and Malaysia. A meta-analysis using the data from the 3 populations showed an overall odds ratio of 11 (95% CI, 6.2-18; z=8.58; P < .00001) for CYP2C9*3 association with phenytoin-related severe cutaneous adverse reactions. Delayed clearance of plasma phenytoin was detected in patients with severe cutaneous adverse reactions, especially CYP2C9*3 carriers, providing a functional link of the associated variants to the disease. CONCLUSIONS AND RELEVANCE: This study identified CYP2C variants, including CYP2C9*3, known to reduce drug clearance, as important genetic factors associated with phenytoin-related severe cutaneous adverse reactions.

Updated molecular epidemiology of carbapenem-non-susceptible Escherichia coli in Taiwan: first identification of KPC-2 or NDM-1-producing E. coli in Taiwan.

BACKGROUND: The global spread and increasing incidence of carbapenem-resistant Enterobacteriaceae have resulted in treatment and public health concerns. Here, we present an investigation of the molecular mechanisms and clonality of carbapenem-non-susceptible Escherichia coli (CnSEC) based on a nationwide survey in Taiwan. METHODS: We collected 32 and 43 carbapenem-non-susceptible E. coli isolates in 2010 and 2012, respectively. The genes encoding cabapenemases and plasmidic AmpC-type and extended-spectrum ß-lactamases (EBSLs) were analyzed by polymerase chain reaction (PCR). The major porin channels OmpF and OmpC were evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Molecular typing was performed with pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). RESULTS: The resistance rates of CnSEC isolates to cefazolin, cefotaxime, cefoxitin, ceftazidime, and ertapenem were all 100%, and most (94.7%) isolates were CMY producers. The main mechanism of CnSEC in Taiwan is via plasmidic AmpC ß-lactamase CMY-2 and DHA-1 in combination with the loss of OmpC/F. In 2010, one isolate was confirmed to harbor blaIMP-8; a KPC-2 producer and an NDM-1 producer were detected in 2012. No isolate had VIM- or OXA-carbapenemases. ST131 was the predominant ST type (33.3%). PFGE revealed no large cluster in CnSEC isolates in Taiwan. CONCLUSIONS: The co-existence of plasmidic AmpC ß-lactamase and outer membrane protein loss is the main mechanism for CnSEC in Taiwan. The emergence of KPC-2 and NDM-1 in 2012 and the predominance of ST131 warrant close monitoring and infection control.

Association and prognostic value of serum inflammation markers in patients with leukoplakia and oral cavity cancer.

BACKGROUND: Oral cavity cancer ranks as the fourth leading cancer in men in Taiwan. The development of a serum biomarker panel for early detection and disease monitoring is, therefore, warranted. METHODS: Nine inflammation-associated markers were investigated in 46 patients with leukoplakia, 151 patients with untreated oral cavity squamous cell carcinoma (OSCC), and 111 age- and gender-matched healthy controls using enzyme-linked immunosorbent assay. During a subsequent 28-month surveillance of OSCC patients, serum samples were prospectively collected at predetermined intervals following the completion of therapy. RESULTS: Logistic regression analysis showed matrix metalloproteases (MMP)-2, MMP-9, C-reactive protein (CRP), transforming growth factor-ß1 (TGF-ß1), and E-selectin having the best discrimination power between groups and significant elevation trends of those five markers were noted from control to OSCC. By combining those five markers, a 0.888 and 0.938 area under curve by ROC curve analysis with 67.4% and 80% overall sensitivity and fixed 90% specificity for leukoplakia and OSCC groups were demonstrated. In the follow-up period, 25 OSCC patients developed recurring or secondary tumors. All examined markers had decreased in relapse-free patients following treatment. However, in patients with relapse, interleukin-6, CRP, and serum amyloid A remained at elevated levels. Statistical analysis showed that patients with CRP ≧2 mg/L and E-selectin ≧85 ng/mL at baseline had highest probability of relapse (odds ratio=3.029, p<0.05). CONCLUSIONS: The results indicate that inflammation plays a crucial role in the pathogenesis process of OSCC. By examining the inflammation markers, physicians could potentially identify patients at risk of cancer transformation or relapse.

Influence of teicoplanin MICs on treatment outcomes among patients with teicoplanin-treated methicillin-resistant Staphylococcus aureus bacteraemia: a hospital-based retrospective study.

OBJECTIVES: Higher vancomycin MIC values (≥1.5 mg/L via Etest) may be associated with vancomycin treatment failure among patients with serious methicillin-resistant Staphylococcus aureus (MRSA) infections. As there were limited similar data for teicoplanin, this retrospective cohort study intended to determine the predictive value of teicoplanin MICs for treatment failure among patients with MRSA bacteraemia. PATIENTS AND METHODS: All patients with at least one blood culture positive for MRSA admitted to the hospital between January 2010 and January 2011 were reviewed. Patients with an age ≥18 years and receipt of teicoplanin therapy throughout the course or receipt of <72 h of vancomycin therapy and then teicoplanin for >3 days were enrolled. Teicoplanin Etest(®) MICs and treatment outcomes for MRSA bacteraemia were reviewed to identify the breakpoint of teicoplanin MICs influencing treatment outcomes. RESULTS: Of the 101 patients enrolled, 56 had a lower teicoplanin MIC (≤1.5 mg/L) for MRSA and 45 had a higher MIC (>1.5 mg/L) for MRSA. A lower teicoplanin MIC was associated with a favourable outcome [37 (66.1%) versus 13 (28.9%); P<0.001] and a lower rate of bloodstream infection-related mortality [15 (26.8%) versus 22 (48.9%); P=0.022]. Patients with chronic obstructive pulmonary disease, bacteraemic pneumonia or higher Pittsburgh bacteraemia score had an unfavourable outcome (P=0.028, 0.022 and <0.001, respectively). Multivariate analysis showed that teicoplanin MIC >1.5 mg/L, higher Pittsburgh bacteraemia score and bacteraemic pneumonia were independent risk factors for unfavourable outcome. CONCLUSIONS: A higher teicoplanin MIC value (>1.5 mg/L) may predict an unfavourable outcome and higher mortality rate among teicoplanin-treated MRSA bacteraemic patients.

Impact on Macrolide Resistance of Genetic Diversity of Mycobacterium abscessus Species.

Our previous study identified that the Mycobacterium abscessus subsp. abscessus T28 sequevar does not fully represent inducible macrolide resistance. Thus, we initiated a correlation study between genotypes and phenotypes. In total, 75 isolates from patients with skin and soft tissue infections were enrolled in the study. These strains were tested against 11 antimycobacterial agents using Sensitire RAPMYCO plates and the CLSI-recommended broth microdilution method. In order to analyze erm(41) and partial hsp65, rpoB, secA1, and rrl genes, bacterial genomic DNA was extracted from bacteria. The MEGA X software was used for phylogenetic analyses. The most active agents against most M. abscessus species were amikacin and tigecycline. Clarithromycin was effective toward M. abscessus subsp. massiliense and nearly all M. abscessus subsp. abscessus C28 sequevars. Two varieties of M. abscessus subsp. abscessus T28 sequevars did not represent inducible macrolide resistance. Most M. abscessus species showed intermediate susceptibility to cefoxitin and imipenem. Six additional agents were less effective against M. abscessus species. Following phylogenetic analyses, two outliers of M. abscessus subsp. abscessus T28 sequevars seem to represent no inducible macrolide resistance. In addition, we discovered genetic mosaicism of hsp65, rpoB, and secA1 in M. abscessus species was common. T28 sequevars of M. abscessus subsp. abscessus do not fully represent inducible macrolide resistance. The outlier of erm(41) phylogeny of the M. abscessus subsp. abscessus T28 sequevar is possibly due to macrolide susceptibility. Evaluation of the antimicrobial susceptibility of M. abscessus species is a reliable tool for assisting physicians in selecting the most effective antimycobacterial agent(s). IMPORTANCE Macrolides are the mainstays of the antimycobacterial regimens against Mycobacterium abscessus species (formerly Mycobacterium abscessus complex). erm(41) confers inducible macrolide resistance for M. abscessus subsp. bolletii strains, and the majority of M. abscessus subsp. abscessus T28 sequevars. Furthermore, the acquired macrolide resistance of M. abscessus species is due to a point mutation in rrl. However, not all M. abscessus subsp. abscessus T28 sequevars have inducible macrolide resistance. Exploration of the mechanism of macrolide resistance requires an understanding of genetic diversity. The genetic mosaicism of the erm(41), rpoB, hsp65, and secA1 genes within three subspecies of M. abscessus species is not uncommon. The T28 sequevar of erm(41) confers inducible macrolide resistance to the genetic mosaic strain. The development of new anti-M. abscessus species infection overcoming inducible macrolide resistance and/or acquired macrolide resistance is a crucial issue.

Increasing ceftriaxone resistance in Salmonellae, Taiwan.

In Taiwan, despite a substantial decline of Salmonella enterica serotype Choleraesuis infections, strains resistant to ciprofloxacin and ceftriaxone persist. A self-transferable bla(CMY-2)-harboring IncI1 plasmid was identified in S. enterica serotypes Choleraesuis, Typhimurium, Agona, and Enteritidis and contributed to the overall increase of ceftriaxone resistance in salmonellae.

A 7-year surveillance for ESBL-producing Escherichia coli and Klebsiella pneumoniae at a university hospital in Taiwan: the increase of CTX-M-15 in the ICU.

To monitor the changing trend of extended-spectrum beta-lactamase (ESBL)-producing bacteria, a 7-year continuous study was launched in 2001 at the largest tertiary hospital in Taiwan. A significant increase over the study period was evident for ESBL-producing isolates of Escherichia coli (4.8-10.0%) and Klebsiella pneumoniae (15.0-23.4%). Molecular investigation conducted in three separate periods revealed the prevalent ESBL types and their genetic relatedness. CTX-M-producing isolates (73.8%) were more prevalent than SHV-type ESBLs (37.0%), the most frequent being CTX-M-14 (34.3%), CTX-M-3 (25.9%), and SHV-12 (25.7%). However, a marked increase of CTX-M-15-producing isolates from 2.1% in 2002 to 29.6% in 2007 was also noted. The increase of ESBL-producing isolates in both species may be mainly due to the horizontal transmission of resistance plasmids, while clonal expansion of some epidemic strains further added to the dispersion of ESBL-producing K. pneumoniae.

Non-typeable Streptococcus pneumoniae infection in a medical center in Taiwan after wide use of pneumococcal conjugate vaccine.

BACKGROUND: Streptococcus pneumoniae is one of the most common pathogens to cause mucosal and invasive infection in humans. Most of the infection could be prevented through immunization by vaccines containing capsular polysaccharides but some infection may be caused by unencapsulated strains. METHODS: Clinical isolates of S.pneumoniae from January 2012 to December 2015 at Chang Gung Memorial Hospital, Taiwan. Serotyping by PCR method was performed. Clinical and laboratory information of patients infected by non-typeable pneumococci (NTP) were collected and analyzed. RESULTS: During the study period, 39 NTP isolates were identified. Most (21 of 39, 53.9%) were collected from purulent upper respiratory tract secretion. Others were from corneal abscess, sputum, and one from blood of a newborn. We recorded a 3.6-fold increase in the rate of isolation from 1.4% in 2012 to 5.0% in 2015 (p = 0.063). Co-infection was found in 24 cases; the major co-infecting pathogens included non-typeable Hemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus. Most (39 of 40, 97.5%) of the isolates were susceptible to both penicillin and ceftriaxone. The dominant sequence type ST1106 and an emerging sequence type ST7502 were recognized. CONCLUSIONS: A gradual increase of NTP infection was found in northern Taiwan in the pneumococcal conjugate vaccine era. Non-typeable pneumococci can cause respiratory and ophthalmological mucosal infection. Invasive infection can occur in newborns or young infants. Most of the isolates remained susceptible to penicillin and ceftriaxone.

Immunologic analysis of HIV-uninfected Taiwanese children with BCG-induced disease.

OBJECTIVES: The aim of this study was to evaluate immunity in HIV-uninfected children with bacille Calmette-Guerin-induced disease (BCG-ID) over an 8-year period, with particular emphasis on underlying diseases. METHODS: Patient afflicted with BCG-ID proven by clinical courses, dermatologic features, pathology, specific polymerase chain reaction, and/or spoligotyping were enrolled between 2000 and 2007. Lymphocyte proliferation, polymorphonuclear function, interleukin (IL)-12/23-interferons (IFN)-gamma circuit, and Toll-like receptor 2-associated signaling were investigated. RESULTS: Of the 271,618 total live births who received the BCG vaccine, eight patients (seven males) with BCG-ID were enrolled during an 8-year period and presented as three disseminated, two distant, and three regional BCG-ID. Their age at onset ranged from 1 to 28 months. All had a vaccine-injection scar except for one with lower CD3 and natural killer cells, compatible with severe combined immunodeficiency (SCID) identified by IL-2 receptor common gamma chain (IL2RG) mutation (Arg226Lys). The other SCID patient with de novo IL2RG mutation (Trp74Gly) had more recurrent infections. The third patient with primary autoimmune neutropenia had disseminated BCG-ID extending to abdominal wall. The fourth patient with chronic mucocutaneous candidiasis had regional BCG-ID and impaired lymphocyte proliferation to Candida and BCG antigens. No defective evidence of polymorphonuclear functions, IL-12/23-IFN-gamma circuit, and Toll-like receptor 2-associated signaling was detected in the remaining four patients. CONCLUSION: Immunologic analysis in HIV-uninfected patients with BCG-ID reveals primary immunodeficiency diseases, especially in those with deficiencies in T-cell and neutrophil functions observed in our cohort, including primary autoimmune neutropenia and chronic mucocutaneous candidiasis.

Antimicrobial susceptibility of Streptococcus pneumoniae at a university hospital in Taiwan, 2000-07: impact of modified non-meningeal penicillin breakpoints in CLSI M100-S18.

OBJECTIVES: In 2008, a new set of penicillin breakpoints was published in the CLSI revised guideline, M100-S18, to define the susceptibility of non-meningeal isolates of Streptococcus pneumoniae. The impact of the change is studied and discussed. METHODS: Laboratory data on pneumococcal isolates collected from Chang Gung Memorial Hospital during 2000-07 were analysed using the original and modified penicillin CLSI breakpoints. RESULTS: A total of 3729 non-duplicate isolates were identifed, including 43 (1.2%) meningeal isolates showing high rates of penicillin (79.1%) and ceftriaxone (34.9%) resistance. For non-meningeal isolates, penicillin non-susceptibility was reduced significantly from 75.1% (72.4% in 2000-03 increasing to 77.4% in 2004-07) to 16% (28.6% in 2000 decreasing to 2.4% in 2007) if the modified breakpoints were applied. However, isolates for which penicillin MICs were 1-2 mg/L increased significantly from 34.2% in 2000 to 59.8% in 2007. Ceftriaxone non-susceptibility also increased significantly from 2.8% before 2005 to 18.4% thereafter. A quarter (25.7%) of the pneumococcal isolates were recovered from patients <10 years old. Higher resistance to penicillin (89.8% versus 70.4%; or 19.1% versus 13.2% by the modified breakpoints) or ceftriaxone (11.1% versus 5.8%) was found among these isolates, compared with those from older patients. CONCLUSIONS: With the implementation of the new breakpoints, clinicians may continue to use penicillin for the treatment of non-meningeal pneumococcal infections in preference to other drug classes. However, as isolates with borderline penicillin MICs are increasing, continued surveillance of pneumococcal susceptibility to penicillin will be needed.

Clinical manifestations, antibiotic susceptibility and molecular analysis of Mycobacterium kansasii isolates from a university hospital in Taiwan.

OBJECTIVES: Mycobacterium kansasii causes a variety of infections. Although previous reports on the prognosis of antimicrobial therapy have been mostly satisfactory, problems involving treatment failure or relapse have been encountered. The purpose of this study was to establish a relationship between the clinical treatment outcomes of M. kansasii infections and bacterial drug susceptibility, and their clonality. METHODS: A total of 37 M. kansasii clinical isolates and clinical information on 34 patients were retrospectively collected in a tertiary medical centre in Taiwan. Bacterial drug susceptibility was determined by the microdilution method. The phylogenetic relationship was analysed by PFGE analysis. RESULTS: Results of PFGE typing revealed a major cluster (cluster I) and eight other divergent patterns. Two/three strains leading to treatment failure were also multidrug resistant and belonged to cluster I. CONCLUSIONS: A relationship between high drug resistance and genetic relatedness of some M. kansasii strains was established. This was associated with clinical treatment failure.

Methicillin-resistant Staphylococcus aureus nasal carriage in international medical conference attendees.

BACKGROUND: Carriage of methicillin-resistant Staphylococcus aureus (MRSA) is associated with its transmission. International travels and massive gatherings may accelerate such transmission. MRSA carriage was surveyed among the attendees of two international medical conferences held in Taipei in 2010. METHODS: A total of 209 attendees from 23 countries were recruited. Nasal specimens were collected from each volunteer and subjected to polymerase chain reaction (PCR) detection for MRSA. Molecular analysis, including pulsed-field gel electrophoresis, multilocus sequence typing (MLST), typing of staphylococcal cassette chromosome mec (SCCmec) and staphylococcal protein A (spa) genes, and detection of Panton-Valentine leukocidin (PVL) and sasX genes, was performed. RESULTS: MRSA carriage was detected in 10 (4.8%) attendees from Vietnam (3/8, 37.5%), Korea (2/6, 33.3%), Japan (2/41, 4.9%), Philippines (2/52, 3.8%), and Bangladesh (1/4, 25.0%). The proportion of MRSA colonizers was significantly higher in the local hospital group compared to those from the other groups (3/17 vs. 7/192, p < 0.05). Six MRSA isolates were available for molecular analysis. They all carried a type IV SCCmec gene. Five pulsotypes were identified; four genotypes, respectively, were identified by MLST and spa typing. None of the isolates carried either PVL or sasX genes. None of common molecular characteristics was shared by isolates from different countries. Most of these isolates were local endemic community clone in each country. CONCLUSIONS: As healthcare workers, a certain proportion of international medical conference attendees harbored MRSA in their nares, mostly local endemic community clones in each country, which has the potential of spread among attendees.

Resistance mechanisms and molecular epidemiology of carbapenem-nonsusceptible Escherichia coli in Taiwan, 2012-2015.

PURPOSE: This study aimed to investigate the resistance mechanisms and molecular epidemiology of carbapenem-nonsusceptible Escherichia coli (CnsEC) in Taiwan. PATIENTS AND METHODS: From 2012 to 2015, 237 E. coli isolates with minimum inhibitory concentrations of imipenem or meropenem >1 µg/mL were collected in a nationwide surveillance and subjected to polymerase chain reaction (PCR) for carbapenemase, AmpC-type ß-lactamase, and extended spectrum ß-lactamase (ESBL) genes. We evaluated outer membrane proteins (OmpF and OmpC) loss and conducted multilocus sequence typing and pulsed-field gel electrophoresis (PFGE). Isolates that were resistant to all carbapenems were designated as pan-carbapenem-resistant E. coli (pCREC) in this study. RESULTS: The predominant resistance mechanism of CnsEC in Taiwan was the CMY-2 ß-lactamase in combination with OmpF and OmpC loss. Sequence type 131 was the most prevalent type (29.2%). Among 237 CnsEC isolates, 106 (44.7%) isolates were pCREC and 18 (7.59%) produced carbapenemase. The prevalence of carbapenemases increased from 6% in 2012 to 11.36% in 2015. Various carbapenemases including KPC-2, IMP-8, NDM-1, NDM-5, VIM-1, OXA-48, and OXA-181 were identified, with NDM-1 being the most common (38.9%) carbapenemase. Comparison between pCREC and non-pCREC among the non-carbapenemase-producing CnsEC isolates revealed SHV, CMY, co-carriage of SHV and CTX-M and concurrent loss of both OmpF and OmpC were more commonly detected in the pCREC group. PFGE revealed no nationwide clonal spread of carbapenemase-producing E. coli. CONCLUSION: NDM-1 was the most common carbapenemase and combination of CMY-2 and concurrent OmpF and OmpC porin loss was the most prevalent resistance mechanism in CnsEC in Taiwan.