Bacteremia caused by Mycobacterium neoaurum.

An immunocompromised patient with an indwelling Hickman catheter developed Mycobacterium neoaurum bacteremia. This rapidly growing mycobacterium was previously isolated from soil, dust, and water but has not been described as a human pathogen. The infection responded to therapy with cefoxitin and gentamicin. It was not necessary to remove the Hickman catheter.     

Bacteremia caused by Vibrio hollisae.

Vibrio hollisae was recovered from the bloodstream of a 36-year-old man with chronic active hepatitis who was admitted to the hospital with signs of gastrointestinal illness. V. hollisae is an infrequent human pathogen associated with seafood ingestion. No etiologic link to seafood was demonstrated in this case report.     

Bacteremia caused by a strain of Desulfovibrio related to the provisionally named Desulfovibrio fairfieldensis

Eight isolates of Desulfovibrio spp. have been obtained over 5 years from abdominal or brain abscesses or blood. Seven isolates were part of a mixed flora [corrected]. One strain was isolated in pure culture from the blood of a patient with peritonitis of appendicular origin. According to the 16S rRNA gene sequences, this strain was close to Desulfovibrio fairfieldensis. The present report describes the fourth isolate of this recently described species to be isolated in pure culture or as a predominant part of the flora and to be associated with infectious processes. Thus, D. fairfieldensis may possess a higher pathogenic potential than other Desulfovibrio species.     

Bacteremia caused by a recently described novel Desulfovibrio species.

An obligately anaerobic, fastidious, slowly growing, spiral, gram-negative bacterium was isolated from the blood of a 75-year-old man with acute onset of pyrexia. The patient responded rapidly to appropriate antibiotic therapy. Extensive investigation failed to detect a focus for the infection. Phenotypically, the organism was consistent with Desulfovibrio species. Microscopic investigation revealed an organism with a vibrioid or spirillioid morphology with rapidly progressive motility by means of a single polar flagellum. Biochemically, the organism produced large amounts of H2S and contained desulfovirdin. The 16S rRNA gene sequence of the organism was found to be most similar to those of members of the genus Desulfovibrio, with identical sequence homology to the newly proposed species described by Tee et al. (W. Tee, M. Dyall-Smith, W. Woods, and D. Eisen, J. Clin. Microbiol. 34:1760-1764, 1996). This is a second unrelated isolation of this novel species from two widely different locations in Australia. The two isolates show some phenotypic differences, indicating that they are different strains of the same species.     

Development of metronidazole-resistant lines of Blastocystis sp.

Metronidazole (MTR) is frequently used for the treatment of Blastocystis infections, but with variable effectiveness, and often with treatment failures as a possible result of drug resistance. We have developed two Blastocystis MTR-resistant (MTR(R)) subtype 4 WR1 lines (WR1-M4 and WR1-M5), with variable susceptibility to a panel of anti-protozoal agents including various 5-nitroimidazoles, nitazoxanide and furazolidone. WR1-M4 and WR1-M5 were developed and assessed over an 18-month period and displayed persistent MTR resistance, being more than 2.5-fold less susceptible to MTR than the parent isolate. The MTR(R) lines grew with a similar g time to WR1, but were morphologically less consistent with a mixture of size. All Blastocystis isolates and the MTR(R) lines were most susceptible to the 5-nitroimidazole drug ronidazole. WR1-M5 was apparently cross-resistant to satranidazole and furazolidone, and WR1-M4 was cross-resistant to nitazoxanide. These MTR(R) lines now provide a valuable tool for the continued assessment of the efficacy and mechanism of action of new and established drugs against a range of Blastocystis sp. subtypes, in order to identify a universally effective drug and to facilitate understanding of the mechanisms of drug action and resistance in Blastocystis.     

Bacteremia caused by a lactose-fermenting, multiply resistant Salmonella typhi strain in a patient recovering from typhoid fever.

A female patient suffered a typical attack of typhoid fever due to a lactose-negative, fully susceptible Salmonella typhi strain. During convalescence she became febrile, and a lactose-fermenting S. typhi strain resistant to ampicillin, chloramphenicol, tetracycline, and trimethoprim was isolated from blood culture. This isolated was shown to harbor a plasmid which cotransferred lactose fermentation and antibiotic resistance.     

Treatment of infections caused by metronidazole-resistant Trichomonas vaginalis

Infections with the sexually transmitted protozoan Trichomonas vaginalis are usually treated with metronidazole, a 5-nitroimidazole drug derived from the antibiotic azomycin. Metronidazole treatment is generally efficient in eliminating T. vaginalis infection and has a low risk of serious side effects. However, studies have shown that at least 5% of clinical cases of trichomoniasis are caused by parasites resistant to the drug. The lack of approved alternative therapies for T. vaginalis treatment means that higher and sometimes toxic doses of metronidazole are the only option for patients with resistant disease. Clearly, studies of the treatment and prevention of refractory trichomoniasis are essential. This review describes the mechanisms of metronidazole resistance in T. vaginalis and provides a summary of trichomonicidal and vaccine candidate drugs.     

Bacteremia caused by Arcobacter cryaerophilus 1B.

Arcobacter cryaerophilus group 1B, a gram-negative, curved or helical bacillus primarily known as a bovine and porcine pathogen, was isolated from the blood of a uremic patient with hematogenous pneumonia. The patient was treated successfully with ceftizoxime and tobramycin.     

Bacteremia caused by Clostridium intestinale

We describe a case of Clostridium intestinale bacteremia in a previously healthy adolescent female presenting with fever and abdominal pain. The bacterium was definitively identified via 16S rRNA gene sequencing. This is the first report, in the world literature, of human infection caused by this microorganism.     

Bacteremia caused by Janibacter melonis

We report a case of bacteremia caused by Janibacter melonis, a recently described aerobic actinomycete originally isolated from a spoiled oriental melon. Our patient's blood culture isolate was identified by partial 16S rRNA gene sequencing. This is the first report of the recovery of Janibacter species from humans.     

Bacteremia caused by Clostridium symbiosum

We describe a fatal case of Clostridium symbiosum bacteremia in a 70-year-old man with metastatic colon cancer. Our report is the first, in the world literature, of human infection caused by this microorganism.     

Bacteremia caused by a novel species of Sphingobacterium

A Gram-negative rod was isolated from the blood cultures of an 84-year-old man with foot cellulitis. The bacterium was first identified as Sphingobacterium spiritivorum on the basis of standard assimilation tests. However, sequencing analysis of its 16S rRNA genes and whole genome hybridization studies with other related bacteria showed that this isolate belongs to a so far undescribed species of Sphingobacterium , close to S. mizutae . This bacterium was susceptible to most of the antibiotics tested, including glycopeptides, but was resistant to aminoglycosides and polymyxins. Treatment with amoxicillin–clavulanate cured the infection.     

Bacteremia and infection of a hip prosthesis caused by Bacillus alvei.

Of the 34 Bacillus species described, 10 have been reported to cause infection in humans and 6 are insect pathogens. We report a case of an infected prosthetic hip caused by Bacillus alvei, only the third documented case of human infection with this organism.     

Bacteremia caused by Salmonella enterica serotype Choleraesuis in Taiwan.

Since 1995, there has been a steady increase in the number of reported cases of Salmonella enterica serotype Choleraesuis (S. Choleraesuis) sepsis in Taiwan. Representative Taiwanese survey data from 1996 to 2004 revealed that these adult patients with S. Choleraesuis bacteremia presented with primary bacteremia (57%, especially immunocompromised hosts), mycotic aneurysm (16%), and fever (86%) predominantly. S. Choleraesuis septicemia demonstrated a higher invasion index (with secondary involved sites) than other Salmonella spp. In swine experiments, the inoculation dose of 10(3) colony forming units S. Choleraesuis was cleared without apparent sequelae. Transmission of specific strains (with mutations of GyrA and parC, subsequently resistance to fluoroquinolones) from swine, and the acquisition of genes (CMY-2, AmpC complex) encoding beta-lactamases (with resistance to extended-spectrum cephalosporins) have been implicated in the evolution of multiresistant phenotypes of S. Choleraesuis. The virulence plasmid of S. Choleraesuis (pSCV), and other genes mediating adhesion to the epithelial cell membrane of the gastrointestinal tract, were considered important pathogenic factors for S. Choleraesuis. Vaccines for domestic animals combined with effective controls on antibiotic use offer the greatest potential to control the increasing impact of S. Choleraesuis on humans.     

Bacteremia and subcutaneous abscess caused by Proteus penneri in a neutropenic host.

Proteus penneri bacteremia and concomitant subcutaneous infection developed in a neutropenic patient with acute lymphocytic leukemia. The skin infection occurred while the patient was being treated empirically with cefoperazone and metronidazole. This case demonstrates the invasive potential of this microorganism in the proper setting.     

Bacteremia caused by Achromobacter species in an immunocompromised host.

A case of bacteremia caused by Achromobacter species in an immunocompromised patient is described. The patient responded to antibiotic therapy. Detailed antibiotic susceptibility data are presented.     

Bacteremia and infective endocarditis caused by a non-daptomycin-susceptible, vancomycin-intermediate, and methicillin-resistant Staphylococcus aureus strain in Taiwan

We describe the development of nonsusceptibility to daptomycin and vancomycin during treatment for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia associated with infective endocarditis and probable septic thrombophlebitis in a uremic patient. MRSA bacteremia persisted during glycopeptide and subsequent daptomycin treatment but cleared after 5 days' treatment with linezolid and fusidic acid.