Activity of an Antimicrobial Hydrocephalus Shunt Catheter against Propionibacterium acnes

Abstract

Shunt infection is a major complication affecting approximately 10% of procedures. Propionibacterium acnes, an anaerobic skin bacterium, is increasingly recognized as a shunt pathogen, causing up to 14% of infections. Though susceptible to penicillin and cephalosporins, P. acnes shunt infections are not preventable by means of perioperative prophylaxis, due to poor cerebrospinal fluid penetration. Antimicrobial shunts with activity against staphylococci are available, but their activity against P. acnes is unknown, and the study was designed to determine this. Three methods of evaluation were used in order to determine the emergence of resistance when exposure is to high inocula for long periods, the time taken to kill 100% of the bacteria attached to the shunt, and the duration of activity under constant flow conditions with repeated bacterial challenge. Despite repeated exposure to high bacterial inocula over 70 days, no resistance was seen. The time taken to kill all attached bacteria, 96 h, was twice that taken to kill attached staphylococci. Nevertheless, under constant flow conditions with repeated challenges, the antimicrobial catheters resisted colonization by P. acnes for 56 days. Using tests that were designed to be clinically predictive when done together, the results suggest that the antimicrobial catheters will be able to prevent colonization of hydrocephalus shunts by P. acnes.Hydrocephalus is the pathological accumulation of cerebrospinal fluid (CSF) in the cerebral ventricles and is caused by a variety of factors, such as intrauterine infection, meningitis, hemorrhage, and tumors. The standard treatment is surgical insertion of a shunt, a silicone tubular device that drains CSF from the cerebral ventricles to another body site, usually the peritoneal cavity. Infection is a serious complication of shunting, the incidence ranging from less than 1% to over 15%, with an overall incidence of about 10% (13,18). Shunt infection in the United States has been estimated to account for more than $100 million in national health care expenditure annually (29). The causative bacteria are usually of skin origin, and coagulase-negative staphylococci (CoNS) predominate. However, a proportion of shunt infections, reported to be approximately 14%, is caused by Propionibacterium acnes, also a normal skin inhabitant (1,4,30). This organism is anaerobic and slow growing and often fails to be detected. Like CoNS, P. acnes adheres to the inner surfaces of the shunt catheters and develops a biofilm (4, 11), leading to antibiotic treatment failure and necessitating shunt removal.Although antimicrobial prophylaxis is almost universally used, its role in reducing the incidence of shunt infections remains controversial. Systemic antibiotics penetrate the blood-cerebrospinal fluid barrier poorly in the absence of inflammation (2,17,20,21,22). The use of intraventricular antibiotics to overcome this has not been successful (6, 32), with the possible exception of the combination of intraventricular gentamicin and vancomycin, wh...

Propionibacterium acnes: infection beyond the skin

“…• Cerebrospinal shunts [13,99] • Dental infections [16][17][18][19] • Elbow joint infection [100] • Endocarditis (native, prosthetic valves) [21,25] • Neurosurgical infections and CNS infections [26,28] • Ocular infections (endophthalmitis, microbial keratitis) [33,36] • Postoperative discitis, spondylodiscitis and spinal infections [38,39,101,102] • Prosthetic joint/orthopedic device-related infections [42,[103][104][105] Review also differ in the production of exocellular proteins [5] and the ability to induce an immune response in sebocytes [51].…”

A Janus-Faced Bacterium: Host-Beneficial and -Detrimental Roles of Cutibacterium acnes

“…acnes is considered an emerging opportunistic pathogen in neurosurgery procedures (Nisbet et al, 2007). It may be responsible for ∼15% of infections associated with shunt tubular devices, that drain cerebrospinal fluid (CSF) from cerebral ventricles to other body sites, usually the peritoneum (Conen et al, 2008;Bayston et al, 2010). Clinical symptoms in shunt infections are non-specific; the absence of fever is common (Aubin et al, 2014).…”

Hydrocephalus in Sudan; Types, Management and Outcome

“…Propionibacterium acnes is believed to be the causative agent and was also found to be very difficult to eradicate even with prolonged antibiotics therapy and also requires shunt removal [5]. Bayston R. suggested that the antibiotic impregnated shunts use may prevent this later type of shunt infections [6].…”