Investigation of an apparent outbreak of Rhodococcus equi bacteremia

During January to April 2007, hospital staff reported 3 patients with Rhodococcus equi bloodstream infections. Isolates were analyzed at the Centers for Disease Control and Prevention, Atlanta, GA, to confirm identification and to assess strain relatedness; 2 were R. equi but genetically distinct, and 1 was identified as Gordonia polyisoprenivorans. Rapid reference laboratory support prevented an unnecessary outbreak investigation.     

Fatal disseminated Scedosporium prolificans infection initiated by ophthalmic involvement in a patient with acute myeloblastic leukemia

Scedosporium prolificans is an opportunistic saprophytic fungus that rapidly disseminates and is intrinsically resistant to currently available antifungal drugs. We report a fatal case of disseminated S. prolificans infection that started with orbital and ocular involvement in a patient with secondary acute myeloblastic leukemia.     

Mycobacterium simiae pulmonary infection unmasked during immune reconstitution in an HIV patient

Highly active antiretroviral therapy in human immunodeficiency virus (HIV) patients may trigger the onset of immune reconstitution inflammatory syndrome (IRIS). Among HIV patients with IRIS, infections are commonly due to Mycobacterium tuberculosis and nontuberculous mycobacteria. We report the first case in Spain and the second in Europe of Mycobacterium simiae pulmonary infection unmasked during immune reconstitution in an HIV patient.     

Muscular abscess caused by Cupriavidus gilardii in a renal transplant recipient

Cupriavidus gilardii is a rare cause of human infection. We report a muscular abscess on the right thigh caused by this organism in a renal transplant recipient, who had suffered a septic shock associated with an extensive cellulitis caused by Streptococcus pyogenes. The patient was successfully treated with surgical drainage and intravenous ciprofloxacin for 13 days. This is the first time that C. gilardii is isolated from a human abscess. C. gilardii should be considered as a cause of human infection, especially in immunocompromised patients. Infection caused by this organism may be underdiagnosed because the identification is very difficult.     

Pulmonary infection due to Pseudozyma aphidis in a patient with burkitt lymphoma: first case report

Fungal infections are being increasingly reported in patients with malignancies. Pseudozyma aphidis is an opportunistic yeast usually isolated from plants and rarely from human samples. In this study, we report the first case of pulmonary infection due to P. aphidis in a Burkitt lymphoma patient.     

Molecular identification of Mycobacterium chimaera as a cause of infection in a patient with chronic obstructive pulmonary disease

This report describes a case of Mycobacterium chimaera infection in a patient with a history of chronic obstructive pulmonary disease where the organism was identified by using molecular methods. M. chimaera was identified from fresh lung tissue and from an instrument-negative mycobacterial growth indicator tube broth culture. The utility of using sequence analysis of the internal transcribed spacer region for the rapid identification of a slow-growing nontuberculous Mycobacterium spp. where conventional culture methods were not successful was shown.     

Co-colonization of vanA and vanB Enterococcus faecium of clonal complex 17 in a patient with bacteremia due to vanA E. faecium

A 53-year-old Vietnamese man with liver cirrhosis was transferred from a Vietnamese hospital to our tertiary care hospital in Korea in order to undergo a liver transplantation. Bacteremia due to vanA Enterococcus faecium was diagnosed, and stool surveillance cultures for vancomycin-resistant enterococci (VRE) were positive for both vanA and vanB E. faecium. Pulsed-field gel electrophoresis analysis revealed that the 2 vanA VRE isolates from the blood and stool were clonal, but the vanB VRE was unrelated to the vanA VRE. vanA and vanB VRE were ST64 and ST18, single-allele variations of clonal complex 17, respectively. This is the first case report of vanA VRE bacteremia in a Vietnamese patient and demonstrates the reemergence of vanB VRE since a single outbreak occurred 15 years ago in Korea. The reemergence of vanB VRE emphasizes the importance of VRE genotyping to prevent the spread of new VRE strains.     

First case of breakthrough pulmonary Aspergillus niveus infection in a patient after allogeneic hematopoietic stem cell transplantation

Aspergillus niveus is a species uncommon in clinical samples, and to date, invasive fungal infections caused by this fungal pathogen have not been described. This is the 1st report on a pulmonary breakthrough aspergillosis caused by A. niveus in a 21-year-old woman after allogeneic hematopoietic stem cell transplantation for Fanconi anemia.     

A fatal case with disseminated Myceliophthora thermophila infection in a lymphoma patient

We report a lethal Myceliophthora thermophila infection in an immunocompromised patient. Based upon the clinical and mycological presentation, an initial diagnosis of invasive aspergillosis was made, possibly delaying optimal management in the patient. Melanized fungi are emerging pathogens that require early identification to improve their unfavorable prognosis.     

A case of catheter-related bloodstream infection caused by Mycobacterium phocaicum

We present a patient with double hit Burkitt's like lymphoma who developed a catheter-related bloodstream infection due to Mycobacterium phocaicum that was identified by rpoB gene sequencing. His infection resolved with 7 weeks of antibiotics and port-a-cath removal.     

Corynebacterium bovis shoulder prosthetic joint infection: the first reported case

We report the first case of Corynebacterium bovis shoulder prosthetic joint infection. The organism was isolated from intraoperative tissue culture and from the removed prosthesis using sonication. A 2-stage exchange and 3 months of antibiotic therapy were performed. C. bovis may cause implant-associated infections, which can manifest as low-grade infection.     

Aeromonas aquariorum septicemia and enterocolitis in a cirrhotic patient

Aeromonas aquariorum is a recently described Aeromonas species. We present a cirrhotic patient with septicemia and bloody diarrhea in whom A. aquariorum was isolated from the blood and stool. The species identification was based on sequence analysis of the partial rpoB and rpoD genes. The A. aquariorum isolates carried genes encoding hemolysin, aerolysin, and the cytotonic enterotoxin Alt. Significant A. aquariorum–induced cytotoxicity in intestinal epithelial cells was also demonstrated.     

Acanthamoeba encephalitis in a patient with systemic lupus treated with rituximab

Acanthamoeba species are free-living protozoa that can infect humans and animals. Acanthamoeba can cause serious central nervous system infections in immunocompromised hosts. Here we report a case of Acanthamoeba encephalitis in a patient with lupus nephritis, 1 month after completing a course of rituximab, an anti-CD20 chimeric antibody.     

KRAS and PIK3CA but not BRAF genes are frequently mutated in Chinese cholangiocarcinoma patients

Cholangiocarcinoma (CCA) is a rare but lethal malignancy arising from the biliary tract epithelium. It has a poor prognosis largely due to the difficulties of early diagnosis and the lack of effective therapies. It is thus imperative to develop new and effective treatments for CCA, which depends heavily on the mechanistic understanding of the disease. Previous studies have suggested that somatic mutations in KRAS, BRAF, and PIK3CA genes are frequently found in several types of human cancers including colon, breast, and lung carcinomas as well as CCA. Yet, the frequency and the involvement of these oncogenic mutations in CCA in Chinese population have not been investigated. In this study, we evaluated the hotspot mutations of KRAS, BRAF, and PIK3CA genes in 34 Chinese CCA patients. Sequencing analysis revealed 13 (38.2%) and 11 (32.4%) patients bearing KRAS and PIK3CA mutations, in which two (5.9%) of them harbored both KRAS and PIK3CA mutations. Surprisingly, no BRAF mutation was detected in all 34 CCA samples. Our findings indicate that somatic mutations in KRAS and PIK3CA but not BRAF oncogenes are closely associated with the development of CCA in Chinese population and provide new potential targets for future therapeutic treatments of the disease.     

Epidemiology and molecular characterization of a clone of Burkholderia cenocepacia responsible for nosocomial pulmonary tract infections in a French intensive care unit

Clustered cases of nosocomial pulmonary infections were observed in a French intensive care unit. Biochemical tests showed the etiologic agents to be part of the Bcc (Bcc). recA polymerase chain reaction-restriction fragment length polymorphism analysis and molecular phylogeny positioned the isolates into Burkholderia cenocepacia. Their recA sequences were found identical to those of ET12 strains responsible of necrotic pneumonia in cystic fibrosis patients. Analyses of a multi locus sequence typing genes set confirmed this proximity and suggested a wide distribution among occidental countries but could not resolve their phylogenetic position unambiguously. A novel marker, ecfB, indicated a significant phylogenetic divergence from ET12 strains. Pulse field gel electrophoresis analysis of SpeI-restricted total genomic DNA of the strains showed a unique profile indicative of a clonal outbreak. Environmental hospital screenings indicated cross-contamination between staff and patients. Bcc strains from outdoor environments were not related to this clone but indicated the presence of Burkholderia multivorans and Burkholderia vietnamiensis.     

Rapid detection of coinfections by Trichomonas vaginalis, Mycoplasma hominis, and Ureaplasma urealyticum by a new multiplex polymerase chain reaction

We developed a multiplex polymerase chain reaction (M-PCR) assay to simultaneously detect Trichomonas vaginalis, Mycoplasma hominis, and Ureaplasma urealyticum. The test is extremely specific and has a sensitivity of 10 cells for T. vaginalis and U. urealyticum and of 1 cell for M. hominis. The technique was validated on vaginal swabs from 240 women presenting symptoms of vaginitis, and results were compared with data obtained using microscopic and culture techniques on the same patients. The M-PCR revealed to be greatly more sensitive and specific than traditional techniques. It has been well demonstrated, in vitro, that T. vaginalis can establish a symbiosis with M. hominis; our data confirm in vivo this strict association: in fact, M. hominis has been detected in 78.6% of all samples positive for T. vaginalis, as compared to only 4.8% of women without trichomoniasis. The species specificity of this association has been confirmed by the absence of any significant correlation between T. vaginalis and U. urealyticum.     

Karyopherin alpha 2 (KPNA2) is associated with the natural resistance to Schistosoma japanicum infection in Microtus fortis

Microtus fortis is a naturally vertebrate host resistant to Schistosoma japonicum infection. In order to understand the molecular mechanism and identify the molecules related to the natural resistance to S. japanicum infection of M. fortis, we screened a gene pool named gE76 by expression cloning and proved it to have high anti-schistosomula effects in our previous work. In this study we identified a clone named gE76.44. We found that the conditioned medium of pcDNA1.1-gE76.44 caused 14.0% schistosomula death rate in 96 h, which was significantly higher than that of negative control (P < 0.05). The gE76.44 was sequenced and the full-length cDNA was 2008 bp with ORF of 1590 bp encoding a polypeptide of 529 amino acid residues. Bioinformatics analysis indicated it was the homologue of karyopherin alpha 2 (KPNA2). To further confirm its anti-schistosome activity, we inserted full length of Mf-KPNA2 (KPNA2 of M. fortis) gene into a retroviral expression vector pLXSN and packaged the recombinant virus with PA317 cells. Mice infected with S. japanicum cercariae were administrated by intravenous injection through tail vein and treated with pLXSN-KPNA2. Adult worms and egg reduction were counted after heart perfusion of mice 42 d after infection. We found that compared with the control, mice injected with Mf-KPNA2 had 39.42% worm burden reduction and 76.50% reduction in LEPG (liver eggs per gram) (P < 0.01), indicating its anti-schistosome effect of Mf-KPNA2 in vivo. Taken together, the results suggested Mf-KPNA2 as a novel anti-schistosome molecule in vitro and in vivo.     

Acinetobacter pittii and Acinetobacter nosocomialis among clinical isolates of the Acinetobacter calcoaceticus-baumannii complex in Sichuan,China

Among 82 clinical isolates of the Acinetobacter calcoaceticus-baumannii complex recovered in 13 hospitals of Sichuan, China, in 2011, 13 were Acinetobacter pittii and 2 were Acinetobacter nosocomialis. Multilocus sequence typing revealed a novel sequence type (ST) of A. nosocomialis and 7 novel STs of A. pittii. Most isolates were hospital-acquired and colonized in the respiratory tract, while 6 cases with pneumonia due to A. pittii were identified. This study provided a snapshot of the local incidence of A. pittii and A. nosocomialis.     

Relapsing Rhodococcus equi infection in a heart transplant recipient successfully treated with long-term linezolid

We report a heart transplant recipient with Rhodococcus equi and Cryptococcus neoformans infection. Despite an initially relapsing course and the acquisition of resistance in vivo, the patient responded to 5 months of linezolid and 6 months of fluconazole. This is the 1st R. equi infection to be cured with linezolid in a heart transplant recipient.     

First report of Paenibacillus cineris from a patient with cystic fibrosis

We describe the recovery of Paenibacillus cineris from a Brazilian cystic fibrosis (CF) patient. Paenibacillus spp. are mainly environmental organisms. Although the role that these species play in lung disease is not known, we highlight the importance of careful attention to unusual bacteria from respiratory secretions of CF patients.