Is skin preparation effective in reducing the incidence of Cutibacterium in shoulder arthroplasty?

The efficacy of topical preparations in reducing the incidence of Cutibacterium acnes at the start and conclusion of total shoulder arthroplasty: a randomized controlled trial

These authors investigated whether preoperative application of topical antimicrobials to the skin reduced superficial colonization and deep tissue inoculation of Cutibacterium in patients undergoing total shoulder arthroplasty who were randomized to receive either topical 

pHisoHex (hexachlorophene (n = 35), 

5% BPO (n = 33), or 

5% BPO with 1% clindamycin (n = 33). 

The initial demographics are shown here. Of note the percentage of male patients was lower for the BPO-C group than for the other groups.

Skin swabs for culture were obtained 

prior to topical application and

before surgery after topical application 

3 intraoperative swabs were obtained at surgery

dermis after incision,

on joint capsule entry, and 

dermis at wound closure

The results are shown below - the three agents performed in a similar fashion. Of note, one of the groups (BPO) differed from the other two in respect to the percentage with colonization before any treatment was applied.

These data show that Cutibacterium can persist in the dermis despite 5 applications of topical skin preparation: 22% of cases had positive dermal cultures at the beginning of the case. 

A positive Cutibacterium skin culture finding prior to surgery was predictive of intraoperative wound contamination: all 24 cases that had a positive swab culture before starting the procedure had at least one positive culture intraoperatively; in most cases, all subsequent swabs showed positive results.

Thus, failure to eradicate Cutibacterium from the skin with topical preparations consistently was associated with deep tissue inoculation.

None of the 101 control sterile swabs were culture positive for Cutibacterium.

Comment: This study demonstrated that surface washes can reduce the percent of positive skin surface cultures. There were no untreated controls, so the effect of the washes on dermal cultures at incision, joint cultures, and  dermal cultures at closure is not known. While it is recognized that young male patients are at greatest risk for Cutibacterium periprosthetic infections, the study group consisted of older patients, one third of which were female.

The authors found that all control sterile swabs were culture negative for Cutibacterium and concluded that "There is, therefore, no need for control swabs to be included in future C acnes studies".  Actually, this is not the case. As pointed out in An Evidence-Based Approach to Managing Unexpected Positive Cultures in Shoulder Arthroplasty the pooled rate of positive control cultures (sterile gauze, sterile swabs, and sterile suture) reported in the literature was 20%. Cutibacterium represented 14 (48%) of the 29 total control positives. Thus, it seems important that each investigator assess the rate of sterile control culture positivity for Cutibacterium in their environment. 

In conclusion, evidence is lacking that skin preparations can reduce the rate of positive deep wound cultures for Cutibacterium in patients known to be at high risk for Cutibacterium periprosthetic infections. In high risk patients (i.e. young male patients with high loads of Cutibacterium on their skin prior to surgery) surgeons may wish to consider the intraoperative use of Betadine washes, topical Vancomycin, and a course of postoperative oral antibiotics.

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Here are some videos that are of shoulder interest

Shoulder arthritis - what you need to know (see this link).

How to x-ray the shoulder (see this link).

The ream and run procedure (see this link).

The total shoulder arthroplasty (see this link).

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

The smooth and move procedure for irreparable rotator cuff tears (see this link).

Shoulder rehabilitation exercises (see this link).

What antibiotic prophylaxis should be used against shoulder periprosthetic infection?

At a recent journal club (thanks, Ben, for organizing), we discussed antibiotic prophylaxis for periprosthetic infections (PJI). It is known that multiple different organisms can cause PJI, but - especially in young healthy males - Cutibacterium is most commonly the culprit. We can provide a bit of an update on some of the key questions

(1) What is the best IV prophylactic antibiotic?

Cephalosporins seem superior as reported in Antibiotic Prophylaxis with Cefazolin Is Associated with Lower Shoulder Periprosthetic Joint Infection Rates Than Non-Cefazolin Alternatives. Among 7,713 shoulder arthroplasties 101were classified as having PJIs. Cutibacterium was identified in 44%, Staph aureus in 19%, Coagulase-negative staph in 12%, and Strep in 5%.

Cefazolin had been administered in 6,879 procedures (89.2%) and non-cefazolin antibiotics (vancomycin, clindamycin, and alternative regimens were administered in 834 procedures (10.8%). 

PJI-free survivorship was greater in shoulder arthroplasties in which cefazolin was administered compared with those in which non-cefazolin antibiotics were administered. Cefazolin administration, compared with non-cefazolin administration, was associated with a 69% reduction in all-cause PJI risk and a 78% reduction in C. acnes PJI risk. 

A higher risk of PJI for both groups was observed with vancomycin; the hazard ratio [HR] was 2.32 for all-cause PJI and 2.94 for Cutibacterium PJI. A higher risk of PJI was also observed for both groups for clindamycin; the HR was 5.07 for all-cause PJI and 8.01 for Cutibacterium PJI. The latter may be due to the pervasive use of clindamycin as a treatment for acne - a practice that may select out clindamycin resistant Cutibacterium.

It is of interest that half of the periprosthetic infections were identified more than two years after the index arthroplasty - this complicates the analysis of antibiotic efficacy in studies with only a couple of years of followup.

(2) Is Clindamycin a good alternative for patients reporting penicillin allergy?

This question was addressed in Perioperative Clindamycin Use in Penicillin Allergic Patients Is Associated With a Higher Risk of Infection After Shoulder Arthroplasty. This study reviewed seven thousand one hundred forty primary shoulder arthroplasties comparing deep surgical site infection risk in 444 patients who received perioperative vancomycin alone or 508 receiving clindamycin alone because of penicillin allergy to 6188 patients who received cefazolin alone without penicillin allergy.

Seventy deep infections were observed; most common organism was Cutibacterium acnes (39.4%). 

Compared with patients treated with cefazolin, infection risk was not different for those treated with

vancomycin, but a higher risk of infection was identified for those treated with clindamycin alone. Thus in contrast to the first study above, these authors concluded that vancomycin is preferred over clindamycin for patients with penicillin allergy. Other studies have demonstrated that patients with multiple allergies have a poorer average prognosis after arthroplasty; one might also wonder whether patients with allergies to penicillin are more susceptible to infection independent of which antibiotic is used.

(3) How can we tell if patient-reported allergy should change the antibiotic choice?

This question was addressed in A Simple Algorithmic Approach Allows the Safe Use of Cephalosporin in “Penicillin-Allergic” Patients without the Need for Allergy Testing. These authors point out that patients who report a penicillin allergy are often given second-line antibiotic prophylaxis during total joint arthroplasty. As seen from the article above, the use of non-cephalosporin antibiotics exposes the patient to an increased risk of PJI. These authors assessed the effectiveness of a simple penicillin allergy screening program to guide the choice of antibiotic prophylaxis.

Basically patients were grouped into three groups

 "intolerance", 

"low risk allergy"

and "high risk allergy"

The "intolerance" and " low-risk"patients received cefazolin, and the high-risk cohort received non-cefazolin antibiotics.

The protocol group (n = 2,078) was propensity score matched 1:1 with a control group that included patients who underwent TJA in the same institution prior to implementation of the protocol, the "control" group.

A total of 357 patients (17.2%) reported a penicillin allergy in the protocol group compared with 310 patients (14.9%) with a recorded allergy in the control group (p = 0.052). 

The number of patients who received non-cephalosporin antibiotics was significantly lower in the protocol group (5.7% compared with 15.2% in the control group; p < 0.001),whereas there was no difference in the rate of total allergic reactions.

Of the 239 low-risk patients (66.9%) in the protocol group, only 3 (1.3%) experienced a mild cutaneous reaction following cefazolin administration. 

There were no differences in the rates of superficial wound, deep periprosthetic, or Clostridioides difficile infections between the protocol and control groups.

(4) Is there evidence that topical Vancomycin is effective against Cutibacterium?

Vancomycin is effective in preventing Cutibacterium acnes growth in a mimetic shoulder arthroplasty

Cutibacterium loves to form biofilms on titanium alloy - one of the most common materials used in shoulder arthroplasty. We recognize that in spite of all available prophylactic measures (skin prep, IV antibiotics), arthroplasty wounds are likely to be inoculated with Cutibacterium. This is especially an issue with patients at high risk (young, healthy males, with high skin surface loads of Cutibacterium and with high serum testosterone levels) as well as those patients truly allergic to cephalosporin antibiotics.

Topical vancomycin powder is a strategy for managing Cutibacterium inoculation at the time of shoulder arthroplasty. Its efficacy is difficult to test through clinical research.

These authors investigated the efficacy of vancomycin as prophylaxis for Cutibacterium growth in vitro using a mimetic shoulder arthroplasty.

Cutibacterium strains were applied to titanium alloy foil and embedded beneath multiple layers of collagen-impregnated cellulose scaffold strips containing human shoulder joint capsular fibroblasts, facilitating the development of an oxygen gradient with an anaerobic environment around the foil and inner layers. Agar plates inoculated with extracts from untreated constructs consistently resulted in the growth of large numbers of C acnes colonies

Ten milligrams of vancomycin powder was applied between the C acnes layer and the human cell–containing scaffold strips to model direct antibiotic application.

Intravenous vancomycin prophylaxis was modeled by adding vancomycin in media at 5 or 20 mg/mL. Treatments with vancomycin powder or vancomycin in media at 20-mg/mL dilution effectively prevented the recovery of any C acnes colonies. However, the lowest vancomycin dilution tested (5 mg/mL) was insufficient to prevent the recovery of C acnes colonies.

Vancomycin powder had no discernible short-term impact on shoulder capsule cell morphology, and the presence of these cells had no discernible impact on vancomycin degradation over time.

The authors concluded that topical vancomycin powder and high levels of vanancomycin in the media effectively prevented C acnes growth in a mimetic model of the shoulder arthroplasty environment. 

In our practice we use topical vancomycin powder in the medullary canal and in the wounds of shoulder arthroplasties, noting that the topical application avoids the risks and inconvenience of systematic vancomycin. 

You can support cutting edge shoulder research that is leading to better care for patients with shoulder problems, click on this link.

Follow on twitter: https://twitter.com/shoulderarth

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Here are some videos that are of shoulder interest

Shoulder arthritis - what you need to know (see this link).

How to x-ray the shoulder (see this link).

The ream and run procedure (see this link).

The total shoulder arthroplasty (see this link).

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

The smooth and move procedure for irreparable rotator cuff tears (see this link).

Shoulder rehabilitation exercises (see this link).

Total shoulder arthroplasty: is Clindamycin a reasonable antibiotic in the penicillin allergic patient?

Perioperative Clindamycin Use in Penicillin Allergic Patients Is Associated With a Higher Risk of Infection After Shoulder Arthroplasty

These authors sought to determine whether infection rates differ between prophylactic antibiotic use for patients with or without penicillin allergy before shoulder arthroplasty surgery.

In 7140 primary shoulder arthroplasties operated between 2005 and 2016 they compared deep surgical site infection risk of patients who received perioperative vancomycin alone (6.2%,N= 444) or clindamycin alone (7.1%, N = 508) for penicillin allergy versus patients who received cefazolin alone without penicillin allergy (86.7%, N = 6,188).

Infections were identified using a comprehensive electronic screening algorithm of electronic medical records and administrative claims of the institution using International Classification of Disease, Clinical Modification, Ninth Revision (ICD-CM-9). They included all positive cultures with preoperative findings consistent with infection and negative cultures with positive surgeon findings for infection.The screening algorithm had a 97.8% sensitivity and 91.5% specificity.

Seventy deep infections (1.2% 5-year cumulative incidence) were observed. 

The most common organism was Cutibacterium (39.4%, N = 27). 

Compared with patients treated with cefazolin, infection risk was not different for those treated with vancomycin (hazard ratio = 1.17, 95% confidence interval 0.42 to 3.30, P = 0.8), but a higher risk of infection was identified for those treated with clindamycin alone (hazard ratio = 3.45, 95% confidence interval 1.84 to 6.47, P , 0.001).

They concluded that a four times higher risk of postoperative infection is found after prophylactic use of intravenous clindamycin antibiotic after shoulder arthroplasty and that Vancomycin is preferred over clindamycin for patients with penicillin allergy.

Comment: This important study gives us "news we can use" and demonstrates the great value of the Kaiser registry.

See related post What if my total shoulder patient says she's allergic to penicillin?

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Can topical agents eliminate Cutibacterium from the skin?

Cutibacterium acnes persists despite topical clindamycin and benzoyl peroxide

These authors examined the effectiveness of topical antimicrobials such as benzoyl peroxide and clindamycin to reduce the levels of Cutibacterium in the skin of the upper backs of 12 volunteers (10 men and 2 women). The upper back of each subject was randomized into 4 treatment quadrants: topical benzoyl peroxide, topical clindamycin, combination topical benzoyl peroxide and clindamycin, and a negative control. The corresponding topical agents were applied to each site twice daily for 3 days.

A 3-mm dermal punch biopsy specimen was obtained from each site and cultured for 14 days to assess for C acnes growth. Positive cultures were assessed for the hemolytic phenotype. 

C acnes grew in 4 of 12 control sites (33.3%), 1 of 12 benzoyl peroxide sites (8.3%), 2 of 12 clindamycin sites (16.7%), and 2 of 12 combination benzoyl peroxide–clindamycin sites (16.7%).

The C acnes hemolytic phenotype was present in 2 of 12 control specimens (16.7%) compared with 0 (0.0%) in the benzoyl peroxide group, 2 of 12 (16.7%) in the clindamycin group, and 2 of 12 (16.7%) in the combination benzoyl peroxide–clindamycin group. There were no statistically significant differences between treatment arms.

Comment:  The lack of statistically significant differences between the treatment groups results from the small number of subjects leading to a lack of statistical power. For example, a post hoc comparison of control vs BPO has a statistical power of only 31%, rather than the desired 80%. A sample size calculation indicates that a study with 40 subjects would show a significant difference.

While this study shows that topical agents did not always eliminate Cutibacterium from the dermis, the apparent reduction in the number of positive cultures may be of clinical interest and importance. Of note, the authors noted no adverse reactions to any of the topical agents.

It seems that the role of topical agents in reducing levels of Cutibacterium merits further study.

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Shoulder arthroplasty - what antibiotic to use in the penicillin allergic patient?

Perioperative Clindamycin Use in Penicillin Allergic Patients Is Associated With a Higher Risk of Infection After Shoulder Arthroplasty

These authors sought to determine whether infection rates differ between prophylactic antibiotic use for patients with or without penicillin allergy before shoulder arthroplasty surgery.
They identified 7140 primary shoulder arthroplasties operated between 2005 and 2016. They compared deep surgical site infection risk of patients who received perioperative vancomycin alone (6.2%,N= 444) or clindamycin alone (7.1%, N = 508) for penicillin allergy versus patients who received cefazolin alone without penicillin allergy (86.7%, N = 6,188).

70 deep infections (1.2% 5-year cumulative incidence)were observed. The most common organism was Cutibacterium acnes.

Compared with patients treated with cefazolin, infection risk was not different for those treated with vancomycin (hazard ratio = 1.17, 95% confidence interval 0.42 to 3.30, P = 0.8), but a higher risk of infection was identified for those treated with clindamycin alone (hazard ratio = 3.45, 95% confidence interval 1.84 to 6.47, P , 0.001).

Comment: Cutibacterium is developing an increased resistance to Clindamycin (see this link and this link). Clindamycin has the additional issue of an increased risk of Clostridium difficile bowel infections.

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We have a new set of shoulder youtubes about the shoulder, check them out at this link.

Be sure to visit "Ream and Run - the state of the art" regarding this radically conservative approach to shoulder arthritis at this link and this link

Use the "Search" box to the right to find other topics of interest to you.

How you can support progress in shoulder surgery

You may be interested in some of our most visited web pages  arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

Propionibacterium - resistance to clindamycin

Propionibacterium acnes Susceptibility and Correlation with Hemolytic Phenotype

These authors tested the antibiotic susceptibility and hemolytic activity of 106 P. acnes strains from sterile body sites (i.e. not from infections) collected at their medical center.

14 were hemolytic and 83 were not.
 

 They found that 9% of the strains were resistant to clindamycin and that there was an association between those phenotypes that were hemolytic on Brucella Blood Agar and clindamycin resistance.

Comment: This study again points out that all Propionibacterium are not the same. Some strains are hemolytic and some are clindamycin resistant. In shoulder arthroplasty prophylaxis and in the treatment of shoulder arthroplasty infections, antibiotics other than clindamycin may be preferable.

This article should be contrasted with

Hemolytic strains of Propionibacterium acnes do not demonstrate greater pathogenicity in periprosthetic shoulder infections

in which patients with at least 1 positive culture growth for P acnes at the time of revision surgery were identified with P acnes isolates available for hemolysis testing. Patients were grouped into
those with P acnes isolates positive (n = 20) and negative (n = 19) for hemolysis. The groups were retrospectively compared based on objective perioperative findings around the time of revision surgery and the postoperative clinical course, including the need for revision surgery. All cases were classified into categories of infection (definite infection, probable infection, and probable contaminant) based on objective perioperative criteria.

In this study the presence of hemolysis was not significantly associated with an increased likelihood of infection (P = .968). Hemolysis demonstrated a 75% sensitivity and 26% specificity for determining infection (definite infection and probable infection categories). The hemolytic and nonhemolytic groups showed no difference regarding preoperative serum erythrocyte sedimentation rate and/or C-reactive protein level (P = .70), number of positive cultures (P = .395), time to positive culture (P = .302), and presence of positive frozen section findings (P = .501). Postoperatively, clindamycin resistance, shoulder function, and the rate of reoperation were not significantly different between the hemolytic and nonhemolytic groups.

These authors concluded that presence of hemolysis was not associated with increased pathogenicity in patients with P acnes–positive cultures following revision shoulder arthroplasty, when assessed by objective perioperative criteria and the postoperative clinical course.

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The reader may also be interested in these posts:

Healing through joint replacement

Supporting progress in shoulder surgery

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Click here to see the new Rotator Cuff Book

Information about shoulder exercises can be found at this link.

Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

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Propionibacterium, benzoyl peroxide and clindamycin

Benzoyl peroxide and clindamycin topical skin preparation decreases Propionibacterium acnes colonization in shoulder arthroscopy

These authors enrolled 65 patients  in a study to investigate whether a benzoyl peroxide and clindamycin preoperative skin preparation reduces the incidence of P. acnes colonization in shoulder arthroscopy. A skin culture specimen was taken at the preoperative visit from standard arthroscopic portal sites. Topical benzoyl peroxide 5% and clindamycin 1.2% (BPO/C) gel was applied to the shoulder every night before surgery. Skin culture was repeated in the operating room before preparation with chlorhexidine gluconate. Final cultures were obtained from within the shoulder after the arthroscopic procedure.

All culture specimens were plated for a full 21 days on Brucella blood agar medium and reported to 21 days.

Initial culture specimens taken before treatment with topical BPO/C were positive for P. acnes in 31 of 65 patients (47.7%). Men (80.6%, 25 of 31 patients) were more often colonized than women (19.4%, 6 of 31 patients) (P = .001).

With 1 application of BPO/C,  4 of 12 (33%) patients were culture positive in the OR prior to skin preparation with chlorhexidine gluconate. 

4 of 19 (21%) patients having >1 application of BPO/C were culture positive in the OR prior to skin preparation with chlorhexidine gluconate. 

The positivity  of the deep cultures were associated with the number of applications; 0% of patients with 2 or more applications had a positive deep culture. 

The two patients had a positive deep culture had fewer than 2 applications of BPO/C . Interestingly, 4 patients who initially had negative skin cultures for P. acnes demonstrated positive skin cultures after topical BPO/C was used. These patients all had negative deep cultures.

Clinical follow-up was documented for all 65 patients for a minimum of 3 months and mean of 6 months postoperatively. There were no signs or symptoms of a clinical infection. Patients with positive deep P. acnes cultures were provided oral antibiotic treatment with doxycycline 100 mg daily for 3 weeks. The topical skin preparation was safe, with only 1 skin reaction (1.5% of patients.) There was no erythema or desquamation in this patient but rather a mild dermatitis. The reaction resolved promptly without treatment, and surgical timing did not need to be altered.

In a prior study, these authors reported on the prevalence of deep colonization of P. acnes in patients undergoing shoulder arthroscopy finding a 72.5% superficial culture rate and 19.6% deep inoculation rate. All positive deep cultures had positive superficial skin cultures.

Comment:  In their discussion, the authors state that "benzoyl peroxide is a powerful topical antimicrobial agent destroying both surface and ductal bacterial organisms and yeasts. Its lipophilic properties permit penetration of the pilosebaceous duct. Once applied to the skin, benzoyl peroxide decomposes to release free oxygen radicals, which have potent bactericidal activity in the sebaceous follicles and an antiinflammatory action. Treatment with BPO/C has demonstrated the added benefit of inhibiting the emergence of antibioticresistant strains of P. acnes."

There may be a downside to the use of BPO/C; the authors point out that "The application of the antibiotic gel in our study revealed positive skin cultures for P. acnes in 3 patients who initially had negative skin cultures. This may be secondary to the dual functions that benzoyl peroxide possesses. Benzoyl peroxide is a direct topical bactericidal agent that is also lipophilic. It penetrates pilosebaceous follicles to break down to benzoic acid and hydrogen peroxide, which releases free oxygen radicals that can oxidize proteins in bacterial cell membranes. Benzoyl peroxide is also known to act as a comedolytic and it is likely that this chemical exfoliating action on the epidermal layer of skin exposes the pathogen for culture."

This study would have been stronger if concurrent rather than historical controls were used (note the apparent difference in superficial culture results for the historical controls (72.5%) vs 47.7% in this study. "Because of changes in contracts, the laboratory used for the cultures had to be changed midway through the study for 16 patients. The second laboratory had a lower overall P. acnes –positive superficial culture incidence (6.3%) than expected from previous studies."

Nevertheless, the article is of interest in its proposal of a prophylactic regimen with BPO/C  as well as a proposal for using post operative doxclyline for patients with positive deep cultures (although these culture results were not finalized until 3 weeks after surgery so it appears that the antibiotics would not be started until these results were known). 

We are left with the thought that some patients may benefit from BPO/C prophylaxis before shoulder surgery. The questions that remain are (1) which patients are appropriate for BPO/C  treatment? (2) how many BPO/C  treatments are indicated? (3) if a patient has a skin reaction to BPO/C, how should that affect proceeding with elective surgery and  (4) when cultures are obtained before and at surgery, how should the results of these cultures inform the use of extraordinary antibiotic prophylaxis? 

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See the essentials of the ream and run.

The reader may also be interested in these posts:

Healing through joint replacement

Supporting progress in shoulder surgery

Consultation for those who live a distance away from Seattle.

Click here to see the new Shoulder Arthritis Book

Click here to see the new Rotator Cuff Book

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery

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Use the "Search" box to the right to find other topics of interest to you.

Propionibacterium - resistance to tetracyclines

Propionibacterium acnes is developing gradual increase in resistance to oral tetracyclines

These authors point out that, while tetracylines are often used to treat Propionibacterium infections,  many tetracycline-resistant P. acnes strains have been isolated in part due to the frequent use of oral tetracycline is frequently used as an acne treatment.

They report a novel tetracycline resistance mechanism in P. acnes. They isolated three doxycycline-resistant strains and six strains that had reduced susceptibility compared to susceptible strains.

All doxycycline-resistant strains had a G1058C mutation in the 16S rRNA gene in addition to an amino acid substitution in the ribosomal S10 protein encoded by rpsJ. Their results show that the S10 protein amino acid substitution contributes to reduced doxycycline susceptibility in P. acnes and suggests that tetracyclines resistance is acquired through a 16S rRNA mutation after the S10 protein amino acid substitution.

Comment: There is no question that Propionibacterium are acquire resistance to Clindamycin and to tetracyclines. Currently, it is not common practice to obtain sensitivities on Propi cultures, but it may be time for this practice to change.

Of note is another recent article:
Antimicrobial activity of topical agents against Propionibacterium acnes: an in vitro study of clinical isolates from a hospital in Shanghai, China

These authors determined the susceptibilities of Propionibacterium to clindamycin and erythromycin The resistance rates to neomycin sulfate, erythromycin, and clindamycin were 11.7%, 49.3%, and 33.4%, respectively. 

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Use the "Search" box to the right to find other topics of interest to you.

You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'

See from which cities our patients come.

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What what are the antibiotic sensitivities of Propionibacterium acnes isolated from orthopaedic implant-associated infections?

Antibiotic susceptibility of Propionibacterium acnes isolated from orthopaedic implant-associated infections

These authors investigated the susceptibility of 55 clinical isolates of P. acnes, obtained from orthopaedic implant-associated infections of the knee joint (n = 5), hip joint (n = 17), and shoulder joint (n = 33), to eight antimicrobial agents: benzylpenicillin, clindamycin, metronidazole, fusidic acid, doxycycline, moxifloxacin, linezolid and rifampicin. Synergy testing was also conducted, in which rifampicin was combined with each of the remaining seven antibiotics.

Phylogenetic typing based on tly sequence analysis showed that 31 isolates were type IA, 13 isolates type IB, and 11 isolates type II.

All isolates (n = 55) were susceptible to most of the antibiotics tested, with the exception of 100% resistance to metronidazole, five (9.1%) isolates displaying decreased susceptibility to clindamycin, and one (1.8%) to moxifloxacin.

None of the antimicrobial agents investigated were synergistic with each other when combined and nine isolates were antagonistic for various antimicrobial combinations. The majority of the antimicrobial combinations had an indifferent effect on the isolates of P. acnes. However, the combination of rifampicin and benzylpenicillin showed an additive effect on nearly half of the isolates.

Comment: This article is very interesting from a number of standpoints:

(1) 22 of the 55 isolates came from hip and knee infections - Propionibacterium is not just a shoulder issue
(2) Clindamycin is not universally effective against Propionibacterium. This is important in that many surgeons use this antibiotic for prophylaxis.
(3) Rifampin appears to be a useful adjunct against Propionibacterium.

Here is another important presentation regarding antibiotics and Propionibacterium. It makes the important observation that a significant percentage of the bacteria isolated from acne patients are now resistant to the most common antibiotics used in acne treatment: Clindamycin, Erythromycin, Tetracycline, Doxycycline and Minocycline. We can only assume that the same is true for the Propionibacterium found in failed arthroplasty.

As our infectious disease experts point out, we seeing two worrisome trends: (1) there are fewer antibiotics available to us for the prevention and management of infections and (2) the bacteria are becoming increasingly resistant to the antibiotics that we do have.

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You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'