amoxicillin-potassium-clavulanate-combination and Brain-Diseases

Gardnerella vaginalis is a facultative anaerobic bacterium that inhabits the genitourinary tract of both healthy women and those with bacterial vaginosis. We report a case of G. vaginalis bacteremia associated with severe toxic encephalopathy in a young woman. Anaerobic blood cultures yielded pure growth of small gram-variable rods later identified as G. vaginalis by both rapid biochemical tests and 16S rRNA gene sequencing. The patient recovered after treatment with amoxicillin-clavulanate according to the in vitro susceptibility testing. The complete genome of G. vaginalis isolate from blood cultures was determined. In vitro G. vaginalis isolate produced elevated amounts of a pore-forming toxin vaginolysin compared to control G. vaginalis isolates. We hypothesize that this toxin, if produced in high amounts in blood, is able to disrupt the blood-brain barrier and exert a toxic activity on brain cells.

Topics: Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Bacteremia; Bacterial Proteins; Bacterial Toxins; Bacterial Typing Techniques; Brain Diseases; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Female; Gardnerella vaginalis; Gram-Positive Bacterial Infections; Humans; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Treatment Outcome; Young Adult

Two regimens of antibiotic prophylaxis are in use at our institution. These protocols consist in perioperative administration of a single dose of amoxicillin-clavulanic acid of 2.2 g at induction and 8 h later and irrigation of the surgical wound with rifamycin before closure. In cases of dirty surgery, placement of external shunts or foreign bodies, we administer vancomycin 1.5 g/die and ceftazidime 6 g/die for 72 h. A retrospective study of all the clean operations we performed in the last 2 years yielded a total of 793 consecutive procedures with three postoperative wound infections. These results are in agreement with the majority of series reported in literature, although different prophylactic protocols are applied and in some cases no prophylactic antibiotics are administered at all. The use of these agents in clean neurosurgery remains, as a matter of fact, controversial. In order to further investigate this issue we took three or more intraoperative samples for culture in 40 clean cases. Only in 2% of these samples were cultures positive. Although lacking statistical significance, these results are interesting indications of the appropriateness of antimicrobial prophylaxis in clean neurosurgery and invite further investigation in that direction.

Topics: Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Antibiotic Prophylaxis; Brain Diseases; Drug Therapy, Combination; Humans; Neurosurgical Procedures; Retrospective Studies; Surgical Wound Infection; Vancomycin