Isolation of Vibrio alginolyticus from blood cultures in a leukaemic patient after consumption of oysters

[Post nearly Drowning Vibrio alginolyticus Septicemia Acquired in Reunion (Indian Ocean)]

AbstractWe report the first case of Vibrio alginolyticus septicemia in the Indian Ocean (Reunion Island), in a patient (70-year-old-man) with multiple underlying conditions, following a nearly drowning in the lagoon of Reunion. From now on, V. alginolyticus should be considered as a possible agent of septicemia in the Indian Ocean, particularly following marine activities.

Two superoxide dismutase (SOD) with different subcellular localizations involved in innate immunity in Crassostrea hongkongensis

SODs are ubiquitous metalloenzymes that can scavenge superoxides in response to various stresses. In the present study, full-length cDNAs of two SOD genes were isolated from Crassostrea hongkongensis (designated ChMnSOD and ChCuZnSOD). The cDNAs are 997 and 918 bp in length with ORFs of 675 and 468 bp (encoding 225 and 156 amino acids), respectively. Sequence analysis revealed a conserved Sod_Fe domain in ChMnSOD, and a Sod_Cu_Zn domain in ChCuZnSOD. Subcellular localization of ChMnSOD is mitochondrial while intracellular expression of ChCuZnSOD is detected. Although their expression overlaps in a wide range of tissues, ChMnSOD mRNA expression is high in gonad while ChCuZnSOD's is strong in adductor muscle. After infection by Vibrio alginolyticus, ChMnSOD mRNA was up-regulated 5 fold (p < 0.05) at 4 h, but returned to normal level 6 h post-infection. The expression of ChCuZnSOD gene showed a slight delay to the infection challenge and was elevated roughly 4 fold after 8 h (p < 0.05), returning to normal at 12 h post-infection. The elevated transcript levels of the two SOD genes in response to V. alginolyticus infection highlights their important functions in eliminating toxic reactive oxygen species (ROS) and protecting organisms from bacterial invasion in C. hongkongensis.

Unusual marine pathogens causing cellulitis and bacteremia in hemodialysis patients: report of two cases and review of the literature

Cellulitis in immunocompetent hosts is usually caused by skin organisms and responds to oral antibiotics. In immunocompromised hosts, such as end-stage renal disease (ESRD) patients, unusual organisms with unpredictable pathogenicity can cause infections. We present two cases with isolates that are usually encountered in coastal waters. The first case describes a 71-year-old African-American ESRD patient who presented with bacteremia secondary to a wound infection after exposure to flood waters in a tropical storm. The second case describes a 70-year-old Caucasian male ESRD patient who developed septic shock after a trivial wound inflicted while on a shrimp boat. Both patients were successfully treated with appropriate antibiotics and supportive measures. The infective agents in both cases belong to the halophilic Vibrio species. The causative agent of cellulitis and bacteremia in the first hemodialysis patient was identified as Vibrio alginolyticus, a non-lactose-fermenting gram-negative bacillus that is rarely isolated from blood. The second patient presented with septic shock owing to Vibrio vulnificus, which is a lactose-fermenting bacillus known to produce severe localized or systemic illness. In both cases, the common features were ESRD-related immunocompromised state and exposure to marine environments. These two cases of life-threatening cellulitis and bacteremia are presented as examples of environmental pathogens common to a marine environment in coastal areas and the imperative need of rapid identification and prompt initiation of treatment in immunocompromised hosts.

Complicated suppurative otitis media in a Greek diver due to a marine halophilic Vibrio sp

Halophilic vibrios are distinct from non-cholera vibrios and have been recognized increasingly as potentially pathogenic bacteria in extraintestinal infections. A case of suppurative chronic otitis media in a Greek diver with Vibrio alginolyticus recovered from an ear drainage culture, is reported. The patient received appropriate antimicrobial therapy and her hearing improved significantly after a tympanoplasty type I was performed. The association of halophilic Vibrio spp. infections with prolonged seawater contact, particularly in subtropical climates, is discussed. In swimmers with extensive exposure to salt water, individual preventive measures and aetiological treatment of ear infections seems to be required in order to reduce the severity of possible Vibrio spp. ear infections.