A Case of Bordetella brochiseptica at a Military Medical Facility in Hawai'i: Phenotypic and Molecular Testing of an Uncommon Human Pathogen.

Bordetella bronchiseptica (B. bronchiseptica) is rarely implicated in human disease. Human infections typically occur in the context of immunosuppression and while human infection has been sporadically reported in the literature, the majority of these reports are largely descriptive and do not explore the molecular and phenotypic properties of the isolates in question. Here we report the isolation and characterization of a B. bronchiseptica isolate derived from an HIV positive patient at Tripler Army Medical Center on O'ahu. This case represents the first published report of human infection of B. bronchiseptica in the state of Hawai'i and the most detailed description of the biochemical and molecular features of a Hawaiian isolate to date.

Mouth in Foot Disease.

Toothpicks are commonly used household items that rarely cause serious injury or infection. Toothpick-related injuries often occur due to ingestion with subsequent trauma/infection at distal sites within the gastrointestinal tract; however, cardiovascular, pleural, and soft tissue infections have been reported. Eikenella corrodens is a gram-negative, facultative anaerobic bacillus found in oral flora associated with bite wound infections. A few case reports describe E. corrodens osteomyelitis from toothpick puncture wounds. We report a case of foot cellulitis and abscess in an elderly diabetic after toothpick puncture injury that was unresponsive to empiric antibiotics. Wound cultures grew E. corrodens and rare Peptostreptococcus species. E. corrodens is resistant to first-generation cephalosporins, macrolides, aminoglycosides, clindamycin, and metronidazole. This case highlights the insidious nature of E. corrodens infections and the need to tailor empiric antibiotics for skin and soft tissue infections based on the mechanism of injury. In addition, this case stresses the importance of protective footwear in diabetics and serves as a cautionary tale regarding the use of seemingly innocuous toothpicks.

An analysis of Staphylococcus aureus infections at a military medical center using the PLEX-ID combined polymerase chain reaction-mass spectrometry system.

Staphylococcus aureus (S. aureus) is a major cause of morbidity in the military health care setting. Culture-based methods are the most common means of identifying infections caused by this agent. However, culture-based methods lack sensitivity and specificity. The Abbott PLEX-ID instrument uses a combination of the polymerase chain reaction and mass spectrometry for the identification of bacterial isolates. We investigated whether the Abbott PLEX-ID system could identify S. aureus in clinical material and facilitate the epidemiological analysis of individual isolates. The PLEX-ID system positively identified 100% of isolates previously found to be methicillin resistant S. aureus by culture. In addition, analysis using the PLEX-ID software revealed that the majority of S. aureus isolates at Tripler Army Medical Center derive from clonal complex 8 and nearly 100% of these strains express the R-variant of the Panton-Valentine leukocidin virulence factor. These results demonstrate the utility of the PLEX-ID system in identifying clinical isolates and reveal an unexpected level of homogeneity among clinical S. aureus isolates recovered at Tripler Army Medical Center. These results also demonstrate the utility of the PLEX-ID system in identifying the resistance patterns, predicting the virulence properties, and tracking the migration of bacterial pathogens in the clinical setting.

A temperature-regulated Campylobacter jejuni gluconate dehydrogenase is involved in respiration-dependent energy conservation and chicken colonization.

Campylobacter jejuni is a gastrointestinal pathogen of humans but can asymptomatically colonize the avian gut. C. jejuni therefore grows at both 37 degrees C and 42 degrees C, the internal temperatures of humans and birds respectively. Microarray and proteomic studies on temperature regulation in C. jejuni strain 81-176 revealed the upregulation at 42 degrees C of two proteins, Cj0414 and Cj0415, orthologous to gluconate dehydrogenase (GADH) from Pectobacterium cypripedii. 81-176 demonstrated GADH activity, converting d-gluconate to 2-keto-d-gluconate, that was higher at 42 degrees C than at 37 degrees C. In contrast, cj0414 and cj0415 mutants lacked GADH activity. Wild-type but not cj0415 mutant bacteria exhibited gluconate-dependent respiration. Neither strain grew in defined media with d-gluconate or 2-keto-d-gluconate as a sole carbon source, revealing that gluconate was used as an electron donor rather than as a carbon source. When administered to chicks individually or in competition with wild-type, the cj0415 mutant was impaired in establishing colonization. In contrast, there were few significant differences in colonization of BALB/c-ByJ mice in single or mixed infections. These results suggest that the ability of C. jejuni to use gluconate as an electron donor via GADH activity is an important metabolic characteristic that is required for full colonization of avian but not mammalian hosts.