A Literature Review of Blood-Disseminated P. marneffei Infection and a Case Study of this Infection in an HIV-Negative Child with Comorbid Eosinophilia.

BACKGROUND: The typical manifestations of Penicillium marneffei (nowadays Talaromyces marneffei) infection in children without human immunodeficiency virus (HIV) remain unclear. The current work presents the case of a child without an underlying disease who was infected with P. marneffei comorbid with eosinophilia. CASE PRESENTATION: A 2-year-old male was infected with P. marneffei. A physical examination revealed a high-grade fever, ulcerated lesions in the oral mucosa, anemia, pruritic erythematous papules on the sac and thigh and watery diarrhea. A chest enhanced computed tomography scan showed multiple small, nodular, high-density shadows in the lungs, multiple lymphadenectasis in the hilum of the lungs and mediastinum, and liquid in the right pleural cavity. The patient's plasma was negative for HIV. Routine blood tests initially indicated that the patient had leucopenia; however, later tests indicated that he had leukocytosis. This peak was caused by a significant increase in eosinophils. The total IgE and specific allergen levels were normal. The stool was negative for parasite eggs. Aspergillus antigen (galactomannan, GM) levels were significantly increased and were present in the serum for a relatively long period. CONCLUSIONS: Eosinophilia can occur during P. marneffei infection, and this finding might provide additional information on the activity of this intracellular parasite. In addition, GM detection might be useful for monitoring the effect of antifungal treatments; however, this theory requires more data for verification.

Emergence and genomic analysis of MDR Laribacter hongkongensis strain HLGZ1 from Guangzhou, China.

Background: Laribacter hongkongensis is a facultative anaerobic, non-fermentative, Gram-negative bacillus associated with community-acquired gastroenteritis and traveller's diarrhoea. No clinical MDR L. hongkongensis isolate has been reported yet. Methods: We performed WGS (PacBio and Illumina) on a clinical L. hongkongensis strain HLGZ1 with an MDR phenotype. Results: HLGZ1 was resistant to eight classes of commonly used antibiotics. Its complete genome was a single circular chromosome of 3 424 272 bp with a G + C content of 62.29%. In comparison with the reference strain HLHK9, HLGZ1 had a higher abundance of genes associated with DNA metabolism and recombination. Several inserts including two acquired resistance gene clusters (RC1 and RC2) were also identified. RC1 carried two resistance gene cassette arrays, aac(6')-Ib-cr-aadA2-Δqac-Δsul1-floR-tetR-tetG and arr-3-dfrA32-ereA2-Δqac-sul1, which shared significant nucleotide sequence identities with the MDR region of Salmonella Genomic Island 1 from Salmonella enterica serovar Typhimurium DT104. There was also an integron-like structure, intl1-arr3-dfrA27-Δqac-sul1-aph(3')-Ic, and a tetR-tetA operon located on RC2. MLST analysis identified HLGZ1 as ST167, a novel ST clustered with two strains previously isolated from frogs. Conclusions: This study provides insight into the genomic characteristics of MDR L. hongkongensis and highlights the possibilities of horizontal resistance gene transfer in this bacterium with other pathogens.

Integron mediated bacterial resistance and virulence on clinical pathogens.

Integron was recognized as mobile elements responsible for the emergence and diffusion of antibiotic resistance, virulence and pathogenicity. The existence of resistant integron in pathogens may consequently lead to the increasing number of clinical failures in bacterial mediated diseases, as well as the expenses. In this study, a total of 22 clinical pathogens (including E. faecalis, S. aureus, K. pneumoniae, Enterobacter, P. aeruginosa and Acinetobacter) were subjected to the identification of class 1-class 3 integrons and drug resistant gene cassettes by high flux LAMP method. According to the results, the clinical isolates were screened as carrying class 1 integron with dfrA12-orfF-aadA2 cassette array, class 1 integron with dfrA17-aadA5 cassette array, class 1 integron with aadA2 cassette, class 1 integron with blaVIM2 cassette, class 1 and class 2 integron with dfrA1-sat1-aadA1 and dfrA12-orfF-aadA2 cassette arrays simultaneously, which was accordantly with the previous data. The optimized high flux LAMP assay was proceeded in water bath at 65 °C for 60 min and determined by naked eye, with the time consumption restricted within 2.5 h. Prior to conventional PCR method, the high flux LAMP assay was demonstrated as a highly-specific and highly-sensitive method. This study offered a valid LAMP method in resistance integrons detection for laboratory use, which was time-saving and easy-determination.

25-Hydroxycholesterol impairs endothelial function and vasodilation by uncoupling and inhibiting endothelial nitric oxide synthase.

Endothelial dysfunction is a key early step in atherosclerosis. 25-Hydroxycholesterol (25-OHC) is found in atherosclerotic lesions. However, whether 25-OHC promotes atherosclerosis is unclear. Here, we hypothesized that 25-OHC, a proinflammatory lipid, can impair endothelial function, which may play an important role in atherosclerosis. Bovine aortic endothelial cells were incubated with 25-OHC. Endothelial cell proliferation, migration, and tube formation were measured. Nitric oxide (NO) production and superoxide anion generation were determined. The expression and phosphorylation of endothelial NO synthase (eNOS) and Akt as well as the association of eNOS and heat shock protein (HSP)90 were detected by immunoblot analysis and immunoprecipitation. Endothelial cell apoptosis was monitored by TUNEL staining and caspase-3 activity, and expression of Bcl-2, Bax, cleaved caspase-9, and cleaved caspase-3 were detected by immunoblot analysis. Finally, aortic rings from Sprague-Dawley rats were isolated and treated with 25-OHC, and endothelium-dependent vasodilation was evaluated. 25-OHC significantly inhibited endothelial cell proliferation, migration, and tube formation. 25-OHC markedly decreased NO production and increased superoxide anion generation. 25-OHC reduced the phosphorylation of Akt and eNOS and the association of eNOS and HSP90. 25-OHC also enhanced endothelial cell apoptosis by decreasing Bcl-2 expression and increasing cleaved caspase-9 and cleaved caspase-3 expressions as well as caspase-3 activity. 25-OHC impaired endothelium-dependent vasodilation. These data demonstrated that 25-OHC could impair endothelial function by uncoupling and inhibiting eNOS activity as well as by inducing endothelial cell apoptosis. Our findings indicate that 25-OHC may play an important role in regulating atherosclerosis.

Emergence and Plasmid Analysis of Klebsiella pneumoniae KP01 Carrying blaGES-5 from Guangzhou, China.

Klebsiella pneumoniae strain KP01 carrying blaGES-5 was identified from a patient in Guangzhou, China. High-throughput sequencing assigned blaGES-5 to a 28.5-kb nonconjugative plasmid, pGES-GZ. A 13-kb plasmid backbone sequence on pGES-GZ was found to share high sequence identities with plasmids from Gram-negative nonfermenters. A novel class 1 integron carrying a gene cassette array of orf28-orf28-blaGES-5 was identified on pGES-GZ, within which orf28 encoded a hypothetical protein possibly correlated to fosfomycin resistance.

resistome analysis of Enterobacter cloacae CY01, an extensively drug-resistant strain producing VIM-1 metallo-ß-lactamase from China.

Resistome analysis of clinical VIM-1-producing Enterobacter cloacae strain CY01 from China revealed the presence of multiple resistance determinants. Two resistance plasmids were identified in CY01. The pCY-VIM plasmid was 14 kb in size and possessed a replicase gene (repA), a gene cluster encoding the partitioning function (parABC), and a carbapenemase gene (blaVIM-1). Another 5.9-kb plasmid, pCY-MdT, with an aac(6')-Ib gene, was very closely related (13 nucleotide differences) to pMdT1, a ColE1 plasmid carrying aac(6')-Ib-cr4.

Value of serum procalcitonin levels in predicting spontaneous bacterial peritonitis.

BACKGROUND/AIMS: Spontaneous bacterial peritonitis (SBP) is a life-threatening disease that poses a great diagnostic challenge to clinicians. We aimed to systemically and quantitatively summarize the current evidence on the diagnostic value of the procalcitonin (PCT) test in identifying SBP. METHODOLOGY: We searched EMBASE, MEDLINE, the Cochrane database and reference lists of relevant articles with no language restrictions through May 2012. We selected original research that reported the diagnostic performance of PCT alone or compared with other biomarkers to diagnose SBP. We summarized test performance characteristics using forest plots, summary receiver operating characteristic curves and bivariate random effects models. RESULTS: We found only three qualifying studies examining 181 episodes of suspected infection with 50 (27.6%) confirmed SBP episodes from 3 countries. Bivariate pooled sensitivity, specificity, positive likelihood ratios and negative likelihood ratios were 86% (95%CI: 73%-94%), 80% (95%CI: 72%-87%), 7.73 (95%CI: 0.91-65.64) and 0.14 (95%CI: 0.01-1.89), respectively. The global measures of accuracy, area under the receiver operating curve (AUROC) and diagnostic odds ratio (DOR), showed PCT has excellent discriminative capability and individual study showed serum PCT testing has better accuracy than ascitic PCT, serum CRP or IL-6 testing. There was evidence of significant heterogeneity but no evidence of publication bias. CONCLUSIONS: The existing literature suggests moderate to high accuracy for PCT as a diagnostic aid for SBP. However, larger, appropriately designed prospective studies are needed to conclusively address the value of serum PCT testing in SBP diagnosis.

[An analysis of resistance of nosocomial infection pathogens isolated from 13 teaching hospitals in 2011].

OBJECTIVE: To investigate the pathogen profile of nosocomial infection in China, and to survey the susceptibility rates of these pathogens to the clinical common antibiotics. METHODS: The non-repetitive nosocomial pathogens isolated from bloodstream infection (BSI), hospital acquired pneumonia (HAP) and intra-abdominal infection (IAI) and the case data were collected from 13 teaching hospitals in different areas of China and sent to a central laboratory for re-identification and susceptibility testing. The levels of minimal inhibitory concentration (MIC) of the common antibiotics were determined by agar dilution method. The data were analyzed by WHONET 5.6 software. RESULTS: A total of 2103 clinical isolates were collected from January to December 2011, of which gram positive cocci and gram negative organisms accounted for 23.2% and 76.8% respectively. The top three pathogens of BSI were E. coli (31.0%, 243/784), K. pneumoniae (14.8%, 116/784) and S. aureus (10.6%, 83/784). The top three pathogens of HAP were A. baumannii (24.2%, 158/652), P. aeruginosa (23.0%, 150/652) and K. pneumoniae (16.4%, 107/652). The top three pathogens of IAI were E. coli (34.3%, 229/667), E. faecium (13.3%, 89/667) and K. pneumoniae (9.6%, 64/667). Methicillin-resistant S. aureus (MRSA) and coagulase negative Staphylococcus (MRCNS) accounted for 64.4% and 78.1% respectively. The susceptibility rates of Staphylococcus species to tigecycline, vancomycin, teicoplanin and linezolid were all 100%. The prevalence of MRSA in HAP was significantly higher than that in BSI or IAI. The susceptibility rates of Enterococcus species to tigecycline, teicoplanin and linezolid were all 100%. The prevalence of extended-spectrum ß-lactamases (ESBL) was 64.3% in E. coli and 38.3% in K. pneumonia. Against Enterobacteriaceae, the most active agents were as following in order: tigecycline (92.3% - 100%) [except P.mirabilis], meropenem (87.5% - 100%), imipenem (87.5% - 100%) [except M. morganii], amikacin (87.5% - 100%), polymyxin B (75% - 100%) [except S. marcescens, P. mirabilis and M morganii], cefepime (67.8% - 100%), cefoperazone-sulbactam (66.6% - 100%), piperacillin-tazobactam (61.5% - 100%). Carbapenem-resistance Enterobacteriaceae strains emerged. The susceptibility rates of P. aeruginosa to imipenem and meropenem were 66.2% and 72.2%, respectively. The susceptibility rates of A. baumannii to imipenem and meropenem were 27.7% and 25.9%, respectively. The most active agents against A. baumannii were polymyxin B (100%), followed by tigecycline (79.8%) and minocycline (50.4%). The susceptibility rates of P.aeruginosa to antibiotics in BSI were higher than those in HAP and IAI. Susceptibility rates of S. maltophilia to trimethoprim-sulfamethoxazole, minocycline and levofloxacin were about 90% or above. Susceptibility rates of B. cepacia to trimethoprim-sulfamethoxazole, ceftazidime and meropenem were all 100%. Several P.aeruginosa and A. baumannii strains were resistant to all tested antibiotics except polymyxin B. CONCLUSIONS: The pathogen profile is different in different types of infection. The prevalence of multi-drug resistant A. baumannii is high, which is still a key problem of nosocomial infection. Tigecycline remains relatively high activity against gram-positive cocci and gram-negative bacteria (except P. aeruginosa and P. mirabilis) in vitro.

A national survey on fungal infection diagnostic capacity in the clinical mycology laboratories of tertiary care hospitals in China.

BACKGROUND/PURPOSE: As the incidence of fungal infections in China increases, the demand for rapid and accurate diagnosis of mycoses is growing. Yet, information on current diagnostic capacity is scarce. METHODS: An online survey was conducted in February 2018 to collect information on mycology testing from tertiary care hospitals across China. Responses from 348 hospitals were analyzed, and a scoring system was designed and employed to assess the overall diagnostic capacity. RESULTS: Most of the surveyed hospitals did not have separate laboratory space, manpower, or equipment dedicated for fungal testing. Conventional staining methods were widely available (>70%), whereas GMS and fluorescent staining were less common. Fungal identification services were offered mostly with chromogenic medium, morphological characterization or automated identification systems, other than more advanced methods such as MALDI-TOF MS and DNA sequencing. Fungal serology testing was available in 81.1%, with G test being the most often used. Though 91.8% of the respondents had the ability to perform antifungal susceptibility testing for yeasts, less than 13% conducted such testing for molds. The percentage of laboratories participating in External Quality Assessment programs and research was 57.5% and 32.5%, respectively. The average score for the 348 surveyed hospitals was 37.2 (out of a maximum of 89 points), with only 15 hospitals scoring >60, suggesting a general lack of high-quality mycology laboratories. CONCLUSIONS: The overall clinical testing capacity for fungal infection in China is insufficient. More investment and training efforts are warranted to establish centers of excellence and promote access to high-quality diagnostic services.

[Distribution and drug-resistance of 3 500 gram-negative bacteria in Guangzhou].

OBJECTIVE: To investigate the distribution and drug-resistance of the common gram-negative bacteria in Guangzhou. METHODS: From July 2001 to August 2003, the resistance of 3 500 strains of common gram-negative bacteria isolated from 13 hospitals in Guangzhou to 15 to 21 antibiotics was determined by standard Kirby-Bauer method according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS, 2000). WHONET-5 software was used to analyze the data. RESULTS: Totally 3 500 gram-negative bacterial strains were isolated from 13 hospitals in Guangzhou in the past two years, and the top 3 most common pathogens of them were Escherichia coli (1 244 strains, 35.5%), Klebsiella pneumoniae (900 strains, 25.7%), and Pseudomonas aeruginosa (547 strains, 15.6 %). The total prevalence of extended-spectrum beta-lactamases (ESBLs)-producing strains was 31.0% (1 084/3 500). The prevalences of ESBLs-producing strains in the Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter cloacae, Acinetobacter SP., other Enterobacter SP., Stenotrophomonas maltophilia, and Proteus SP. in Guangzhou were 38.7%, 37.9%, 5.3%, 55.2%, 8.2%, 27.7%, 33.3% and 9.2%, respectively. Among them, 1 463 (41.8%) strains was isolated from the respiratory tract and 943 (26.9%) from the urinary tract. According to our surveillance, the clinical antibacterial drug with the lowest total drug-resistance rates of Gram-negative bacteria was imipenem (8.7%) followed by Cefoperazone/sulbactam (13.3%), while that with the highest resistance was ampicillin (90.9%) followed by nalidixic acid (69.3%). Imipenem was the most effective agents against Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Acinetobacter SP., other Enterobacter SP., and Proteus SP. isolated from 13 hospitals in Guangzhou, with drug-resistant rates of 1.1%, 0.5%, 0.6%, 3.2%, 0.8% and 0%, respectively, whereas the most effective agents against Pseudomonas aeruginosa and Stenotrophomonas maltophilia was cefoperazone/sulbactam, with the drug-resistance rates of 10.8% and 15.9%, respectively. Most of the isolates were multi-drug resistant. The resistance rates of ESBLs-producing strains to 15 to 21 antimicrobial agents were much higher than those of non-ESBLs-producing strains (P<0.05). CONCLUSIONS: Drug resistance of the clinical isolates is a serious problem in Guangzhou, and the increasing prevalence of ESBLs-producing strains of other bacteria should be given full attention. An unanimous and effective strategy for controlling this problem is urgently needed. Imipenem and cefoperazone/sulbactam are the most effective antibiotics against the gram-negative bacteria isolated from the 13 hospitals in Guangzhou.