Outcome of patients over 80 years of age on prolonged suppressive antibiotic therapy for at least 6 months for prosthetic joint infection.

OBJECTIVES: To describe elderly patients treated with prolonged suppressive antibiotic therapy for a prosthetic joint infection (PJI) in cases where the infected prosthesis could not be removed. METHODS: All patients aged ≥80 years with a documented PJI and treated with prolonged suppressive antibiotic therapy for more than 6 months were included retrospectively in this study. The following events were noted: failure including persisting infection, relapse, new infection, treatment discontinuation due to severe adverse events, and related death, and also unrelated death. RESULTS: Thirty-eight patients with a median age of 84 years (80-95 years) were included; there were 24 hip infections, 13 knee infections, and one shoulder infection. The main causative organisms were Staphylococcus aureus (39%) and Streptococcus agalactiae (16%). The most commonly prescribed antibiotics as prolonged suppressive therapy were penicillins. The median follow-up duration was 24 months; 60% of the patients were event-free at 24 months and were still on prolonged suppressive antibiotic therapy. Fifteen events (six failures and nine unrelated deaths) were observed. Hypoalbuminaemia, the presence of a sinus tract, and a staphylococcal PJI were associated with an increased risk of an event. CONCLUSIONS: Prolonged suppressive antibiotic therapy is an alternative therapy in elderly patients with PJI when surgery is contraindicated and when the bacteria are susceptible to well-tolerated oral antimicrobial therapy such as beta-lactams.

One-stage exchange arthroplasty for chronic periprosthetic hip infection: results of a large prospective cohort study.

BACKGROUND: Exchange arthroplasty of one or two stages is required for the treatment of chronic periprosthetic joint infections. Two-stage exchange is costly and has high morbidity with limited patient mobility between procedures. One-stage exchange has been promoted by several European teams as the preferred alternative. The aim of this study was to prospectively analyze the outcome of patients with a periprosthetic hip infection treated with one-stage exchange arthroplasty. METHODS: We performed a prospective cohort study in a French referral center for osteoarticular infections including all periprosthetic hip infections treated with one-stage exchange arthroplasty from November 2002 to March 2010. Direct exchange was performed in chronic periprosthetic hip infection with no or minor bone loss and preoperative identification of a microorganism from joint fluid aspirate. No antibiotic-loaded bone cement was used. Antibiotic therapy was administered for twelve weeks: intravenously for four to six weeks, followed by an oral regimen for six to eight weeks. Follow-up was a minimum of two years. The following events were noted: relapse, new infection, joint revision for mechanical reasons, and periprosthetic hip infection-related and unrelated deaths. RESULTS: One hundred and fifty-seven patients with periprosthetic hip infections with a median infection duration of 258 days (interquartile range, 120 to 551 days) prior to our index surgical procedure for infection were included. Periprosthetic hip infection occurred in ninety-nine cases of primary hip arthroplasty, twenty-seven cases of revision arthroplasty, and thirty-one cases in which the periprosthetic hip infection had been treated previously. A difficult-to-treat organism was isolated in fifty-nine cases (38%). After a median follow-up of 41.6 months (interquartile range, 28.1 to 66.9 months), two relapses, six new infections, nine revisions for mechanical reasons, two related deaths, and nineteen unrelated deaths occurred. CONCLUSIONS: One-stage exchange arthroplasty is an effective surgical procedure in patients with periprosthetic hip infection who have good bone quality. Precise identification of the microorganism(s) and prolonged administration of appropriate intravenous antibiotic therapy are key factors for successful treatment.

Investigation into three dimensional hip anatomy in anterior dislocation after THA. Influence of the position of the hip rotation centre.

BACKGROUND: The components position is a major factor under the surgeon's control in determining the risk of dislocation post total hip arthroplasty. The aim of this study was to investigate the proper three-dimensional components position including the centre of rotation in the case of anterior dislocation. METHODS: Among 1764 consecutive patients who underwent total hip arthroplasty using a direct anterior approach, 27 experienced anterior dislocation. The three-dimensional hip anatomy was investigated in 12 patients who were paired with 12 patients from the same initial cohort who did not experience dislocation and also with 36 control patients with osteoarthritis. A pelvic Cartesian referential was defined to perform the acetabular analysis. The coordinates were expressed as percentages of the pelvic width, height and depth. The anteversion angles were measured. FINDINGS: The hip centre of rotation was significantly shifted medially and posteriorly in the dislocation group when compared to the non-dislocation group and also to the control group. There was no significant difference in component angular position between the dislocation-group and the non-dislocation group. However, the stem anteversion in the dislocation group was increased in comparison to the mean natural femoral anteversion of the control group. INTERPRETATION: A medial and posterior displacement of the hip rotation centre was found to correlate to anterior dislocation post total hip arthoplasty. These results suggest the importance of an accurate restoration of the centre of rotation, whilst avoiding an excessive acetabular reaming which may induce a medial and a posterior displacement. LEVEL OF EVIDENCE: III comparative non randomised.

Monitoring the one year postoperative infection rate after primary total hip replacement.

PURPOSE: Infection of a total hip replacement is potentially a devastating complication. Statistical process control methods have been generating interest as a means of improving the quality of healthcare, and we report our experience with the implementation of such a method to monitor the one year infection rate after primary total hip replacement. METHOD: Infection was defined as the growth of the same organism in cultures of at least two aspirates or intra-operative specimens, or growth of one pathogen in a patient with local signs of infection such as erythema, abscess or draining sinus tract. The cumulative summation test (CUSUM test) was used to continuously monitor the one year postoperative infection rate. The target performance was 0.5% and the test was set to detect twice that rate. RESULTS: Over the three year study period, 2006 primary total hip replacements were performed. Infection developed within one year after surgery in eight (0.4%) hips. The CUSUM test generated no alarms during the study period, indicating that there was no evidence that the process was out of control. CONCLUSION: The one year infection rate after primary total hip replacement was in control. The CUSUM test is a useful method to continuously ensure that performance is maintained at an adequate level.

Osteomyelitis in adults: an underrecognized clinical entity in immunocompetent hosts. A report of six cases.

OBJECTIVE: Osteomyelitis is rare in adults and typically occurs in patients with risk factors such as sickle cell disease or immune deficiency. Cases in immunocompetent adults without sickle cell disease are extremely rare. The objective of this work was to describe the epidemiological, clinical, laboratory, and radiological features and the management of long-bone osteomyelitis in immunocompetent adults without sickle cell disease. METHODS: We conducted a retrospective descriptive study of all immunocompetent adults without sickle cell disease who were admitted to our center between November 2002 and November 2008 for long-bone osteomyelitis. In all patients, the clinical symptoms started in adulthood, in the absence of a childhood history of osteomyelitis. RESULTS: We identified six patients meeting our inclusion criteria over the 6-year study period. The causative microorganism was methicillin-susceptible Staphylococcus aureus in four patients and Salmonella in two patients (wild-type S. typhi and S. enterica, respectively). In each patient, there was a single focus of osteomyelitis and a single causative microorganism. The symptoms developed insidiously and lacked specificity. At presentation, the patients had moderate pain with or without a swelling. There was no fever initially in five patients, three of whom had major diagnostic delays as a result. Treatment associated antibiotics and surgery in all patients and the initial outcome was consistently favorable (median follow-up: 15 months; range: 8-72). CONCLUSION: Osteomyelitis can occur even in immunocompetent adults. The protracted course and atypical presentation of osteomyelitis in immunocompetent adults may lead to major diagnostic delays.

Arthrodesis with internal fixation of the infected ankle.

Arthrodesis may be necessary to avoid amputation when treating an infected tibiotalar joint. In such cases, external or hybrid fixation is usually used. In this retrospective study, we report our experience in treating tibiotalar joint infection by arthrodesis with internal fixation. From March 1992 to October 2005 (13 years, 7 months), 20 patients underwent septic ankle arthrodesis with internal fixation. The mean duration of infection before fusion was 2.5 ± 6.7 years. Arthrodesis was performed with the Méary technique in 9 (45%) cases and with the Crawford-Adams technique in 11 (55%) cases. Internal fixation consisted of screw fixation, staple fixation, or a combination of both. The mean duration of antibiotic treatment was 97.5 ± 37.5 days, and the mean follow-up was 64 ± 36 months, with no patient lost to follow-up. Patients were considered cured if no clinical, biological, or radiologic signs of infection were present at a minimum of 2 years follow-up. The incidence of cure was 85.0% (91.0% with Crawford-Adams and 77.8% with Méary techniques). Radiographic fusion was identified in 89.5% of the cases (91.0% with Crawford-Adams and 87.5% with Méary techniques) at a mean of 4.8 ± 2.4 (range 3 to 11) months postoperative. Tibiotalar arthrodesis in the presence of sepsis can be performed with internal osteosynthesis only under certain conditions. In our experience, this treatment produced satisfactory fusion in 89.5% of patients and eradicated infection in 85.0% of cases.

Continuous clindamycin infusion, an innovative approach to treating bone and joint infections.

The feasibility, safety, and efficacy of prolonged, continuous, intravenous clindamycin therapy were retrospectively evaluated for 70 patients treated for bone and joint infections, 40% of whom were treated as outpatients. The median treatment duration was 40 days, the median daily clindamycin dose was 2,400 mg, and three moderate-grade adverse events occurred. The median serum clindamycin concentrations on days 3 to 14 and days 8 to 28 were 5 and 6.2 mg/liter, respectively; the median concentration was significantly lower (P < 0.02) in patients treated with rifampin (5.3 mg/liter) than in those not treated with rifampin (8.9 mg/liter). Among 53 patients with a median follow-up of 30 months (range, 24 to 53 months), 49 (92%) were considered cured (1 patient had a relapse, and 3 patients had reinfections).

Undetected fracture of an alumina ceramic on ceramic hip prosthesis.

An unusual case of undetected ceramic fracture was discovered by coincidence during total hip arthroplasty revision for sepsis. To our knowledge, this kind of fracture has never been described before. The cup liner was broken in 2 parts, consisting of a large outer annulus and a smaller round central piece that was detached from the superior and posterior part of the cup, creating a hole in the cup. The analysis of the retrievals suggests that the fracture occurred during walking at the contact point between the head and the cup. The ceramic breakage was asymptomatic with no mechanical disorder, suggesting that some ceramic fracture may be tolerated in vivo. However, any evidence of a fractured ceramic component should cause the surgeon to strongly consider revision.

Group B streptococcal prosthetic joint infections: a retrospective study of 30 cases.

OBJECTIVE: To describe the epidemiological, clinical, and laboratory characteristics of patients with group B streptococcal (GBS) prosthetic joint infections, their diagnoses, treatment, and long-term outcomes. METHODS: We conducted a retrospective cohort study including all patients hospitalized from January 1994 through May 2006 for a GBS prosthetic joint infection. RESULTS: The study included 30 patients, aged 35-87 (median 74) years with prosthetic hip (24) or knee (6) infections, 20 with at least one underlying disease. The route of infection was presumed to be hematogenous in 27 patients, and a portal of entry was identified in 9 (genitourinary tract 4, skin 2, gastrointestinal tract 2, oropharynx 1). All patients underwent surgery (6 debridement-synovectomy, 9 1-stage exchange arthroplasty, 8 2-stage exchange arthroplasty, 6 hip resection arthroplasty, and 1 knee arthrodesis) and received prolonged intravenous antibiotics. Four patients relapsed. One patient developed 2 other infections on her knee prosthesis. Two deaths were infection-related, and one was treatment-related. Nineteen patients followed for >/=2 years were cured. One patient was lost to follow-up and 3 died of causes unrelated to infection or treatment within 2 years. CONCLUSION: GBS prosthetic joint infections are mostly acute hematogenous infections that require prompt management for satisfactory outcome. Despite high antibiotic susceptibility, treatment failure is frequent because of the severity of the infection and patients' advanced age, underlying diseases, and relapses.

Outcome of group B streptococcal prosthetic hip infections compared to that of other bacterial infections.

BACKGROUND: Outcome of streptococcal prosthetic hip infection is often thought to be better than that caused by other pathogens. That supposition was not confirmed in our experience with group B streptococcal prosthetic joint infection. OBJECTIVE: We compared outcomes of group B streptococcal and other-pathogen prosthetic hip infections. METHODS: One hundred and thirty nine patients, 24 with group B streptococcal and 115 other-pathogen prosthetic hip infections, were included. The primary outcome was the time from surgical treatment to treatment failure, defined as relapse, infection- or treatment-related death. Secondary outcomes were the times from surgical treatment to relapse or any event (event-free survival). The cumulative incidence estimator was used to model primary and secondary outcomes. Multivariable regression analysis was used to determine a set of independent predictors of treatment failure. RESULTS: With a median follow-up of 22 months, treatment failed more frequently in patients with group B streptococcal prosthetic hip infections (hazard ratio, 4.88 [95% CI, 1.4-17], P=.012). Multivariable analysis retained the American Society of Anesthesiologist score and group B streptococcal infection as independent risk factors of treatment failure; event-free survival was lower for these patients (hazard ratio, 2.64 [95% CI, 1.2-6], P=.02). CONCLUSION: Despite high antibiotic susceptibility, outcomes of group B streptococcal and other-pathogen prosthetic hip infection differ.

Continuous cefazolin infusion to treat bone and joint infections: clinical efficacy, feasibility, safety, and serum and bone concentrations.

Cefazolin has been used for many years to treat bone and joint infections. Because of its time-dependent antimicrobial activity, continuous infusion would potentially be beneficial. We report on the feasibility, safety, and efficacy of prolonged continuous intravenous cefazolin therapy in a cohort of 100 patients, their serum cefazolin levels, and the concomitant bone cefazolin concentrations in 8 of them. This retrospective cohort study included all the patients treated for bone or joint infection with a continuous cefazolin infusion administered over a 12-h period twice daily for >or=2 weeks. Drug monitoring was performed at least twice for all the patients. Serum and bone cefazolin concentrations were determined by standardized disk diffusion microbiological assays. The absence of clinical, biological, and radiological signs of infection after 2 years of follow-up and the same criteria after 1 year of follow-up defined cures and probable cures, respectively. The median treatment duration was 42 days, and the median daily cefazolin dose was 6 g. Half of the patients received parenteral antibiotic therapy on an outpatient basis. Two moderate-grade adverse events were observed. The median serum cefazolin concentrations were 63 microg/ml (range, 13 to 203 microg/ml) and 57 microg/ml (range, 29 to 128 microg/ml) on days 2 to 10 and days 11 to 21, respectively. The median bone cefazolin concentration reached 13.5 microg/g (range, 3.5 to 29 microg/g). The median bone concentration/serum concentration ratio was 0.25 (range, 0.06 to 0.41). Among 88 patients with a median follow-up of 25 months (range, 12 to 53 months), 52 were considered cured and 29 were considered probably cured. Thus, the treatment of bone and joint infections with a prolonged continuous intravenous cefazolin infusion was feasible, effective, well-tolerated, safe, and convenient, making it a strong candidate for home therapy.

Dislocation after total hip arthroplasty using Hueter anterior approach.

A prospective study including 1764 hips has been carried out to evaluate the frequency of dislocation while using the Hueter anterior approach and the correlated factors. The dislocation group was compared with the patients without dislocation. We observed 27 dislocations (1.5%). The dislocation rate when using 28 mm head diameter was 0.5%. Two patients underwent a revision for recurrent dislocations. Correlated factors for dislocation were male sex, high body mass index, etiology of osteonecrosis, low head diameter, high bleeding, and low postoperative ROM. Dislocation risk while using Hueter approach is one of the lowest in the literature. The main disadvantages are the necessity for a specific orthopedic table and a more difficult exposure of the femur.

Propionibacterium acnes: an agent of prosthetic joint infection and colonization.

BACKGROUND: Prosthetic joint infection (PJI) can present a diagnostic challenge, especially with slow-growing and poorly virulent bacteria. OBJECTIVE: To describe the epidemiological, clinical and biological characteristics of Propionibacterium acnes PJI, their treatments and outcomes and compare 2 clinical pictures (according to the time PJI symptoms appeared after the index operation: < or = 2 years, > 2 years). METHODS: We conducted a cohort study on P. acnes PJI. Diagnosis was based on > or = 2 positive cultures of intraoperative specimens taken during revision arthroplasties for infection or presumed aseptic loosening. RESULTS: Fifty patients with prosthetic hip (34), knee (10) or shoulder (6) infections were included and analyzed according to their symptom-free interval: < or = 2 years for 35 and > 2 years for 15 (mean interval: 11+/-6 years). The numbers of previous prostheses (p=0.04) were higher for the shorter-interval group, which had more frequent signs of infection (p=0.004). These findings suggest infection in most of the patients whose PJI symptoms appeared: < or = 2 years after the index operation, and colonization in the majority of those whose symptoms appeared > 2 years after index surgery. Treatment combining exchange arthroplasty with prolonged intravenous antibiotics was successful for 92% of the patients. CONCLUSION: P. acnes can cause different types of PJI: late chronic infections, colonization of loosened prostheses and, exceptionally, acute postoperative infections.

Arthritis due to Mycobacterium xenopi: a retrospective study of 7 cases in France.

BACKGROUND: Mycobacterium xenopi is a nontuberculous mycobacterium responsible for opportunistic and nosocomial infections, chiefly of the lung; few cases of bone and joint infection have been reported. From July 1989 through May 1993, an outbreak of 58 cases of nosocomial discitis due to M. xenopi infection following percutaneous nucleotomy occurred in a French hospital. Peripheral M. xenopi arthritis seems exceedingly rare. We conducted a study to assess the epidemiological and clinical patterns of M. xenopi arthritis. METHODS: We retrospectively reviewed cases of M. xenopi arthritis reported from May 1993 through October 2004. RESULTS: We identified 7 cases, all of which occurred after invasive surgical procedures were performed on the affected joint, suggesting a nosocomial pattern of infection. Two patients may have been contaminated at the hospital where the M. xenopi discitis outbreak occurred. No source was identified in the other 5 patients. Despite the probable nosocomial nature of the infections, the diagnosis was delayed (mean time until diagnosis, 50 months). Repeated collection of deep tissue specimens for bacteriological analysis seemed crucial to the diagnosis. The treatment relied on combination antimicrobial therapy and surgery. Among 11 cases of M. xenopi osteoarticular infection reported in the literature from 1975 to 2005, (arthritis in 9 cases and osteitis in 2), none were nosocomial. CONCLUSION: A high index of suspicion should be maintained to ensure the diagnosis of M. xenopi arthritis before chronic monoarthritis and before the development of irreversible joint damage.

Hip arthroplasty infection with heterogeneous vancomycin-resistant Staphylococcus aureus.

We report a case of heterogeneous vancomycin-resistant Staphylococcus aureus hip arthroplasty infection. Apparent cure was obtained by excision of infected tissues and removal of prosthetic material combined with optimal and closely monitored prolonged intravenous antibiotic therapy including continuous high-dose vancomycin.

Salmonella typhi osteitis can mimic tuberculosis. A report of three cases.

We report three cases of Salmonella typhi osteitis. One patient was an immunocompetent woman with a single focus of osteitis, another had heterozygous sickle cell disease with multifocal osteitis, and the remaining patient had acute discitis. Tuberculosis was considered in all three patients, based on origin from an endemic area (sub-Saharan Africa), a chronic course in the first two patients, and granulomas in a biopsy specimen from one patient.

Contribution of routine joint aspiration to the diagnosis of infection before hip revision surgery.

OBJECTIVES: To define the sensitivity and specificity of routine preoperative hip aspiration for diagnosing hip prosthesis infection (HPI) and to separately analyze subgroups with and without a clinical suspicion of HPI before aspiration. METHODS: From June 1994 to June 1997, all patients scheduled for hip revision surgery underwent aspiration of the hip under image intensifier guidance. Microbiological results were compared between these preoperative specimens and the intraoperative specimens. The reason for surgery was either a clinical suspicion of HPI or pain suggesting loosening. RESULTS: The study patients had had multiple surgical procedures. HPI was suspected clinically in 39.4% of cases. Of the 109 patients who underwent aspiration, 54 had true-negative results, nine had false-negative results, and 44 had true-positive results (there were no false-positive results), yielding a sensitivity of 83% and a specificity of 100%. Diagnostic efficiency was 91.6%, positive predictive value was 100%, and negative predictive value was 85.7%. In the subset of 43 patients with a clinical suspicion of HPI, aspiration identified all the causative organisms in 60.5% of cases. Of the 66 patients with no clinical suspicion of HPI, 12 had HPI, and aspiration provided the diagnosis preoperatively in seven of these patients, radically changing their management plans. Restricting routine aspiration to patients whose prosthesis had been implanted within the last 5 years or whose erythrocyte sedimentation rate (ESR) was above 30 mm/h would not have modified our findings. CONCLUSIONS: Hip aspiration before revision surgery for pain is effective in detecting HPI, which can simulate aseptic loosening. However, this investigation may be noncontributive in patients who have had their prosthesis for more than 5 years and whose ESR is less than 30 mm/h.

[Postoperative osteitis of the pubis: diagnosis, treatment and results]. / Ostéites du pubis postopératoires: prise en charge diagnostique, thérapeutique et résultats.

OBJECTIVE: Osteomyelitis of the pubis is a possible complication of urological and gynaecological surgery. This article reviews this disease which is still a source of controversy. MATERIAL AND METHODS: Between 1984 and 1997, five patients with osteomyelitis of the pubis, following complementary investigations, underwent resection of the symphysis pubis with histological and bacteriological examination, combined with antibiotic therapy. The follow-up was 1.5 months to 4 years. RESULTS: The time to onset of first symptoms was 2 weeks to 5 years. Pain initially presented inflammatory features during the early postoperative period and subsequently became mechanical as the disease became chronic, with intermittent acute episodes in 3 cases. Radiation of the pain and the abnormalities observed on imaging were predominantly unilateral in all patients. Fever and laboratory signs of inflammation were inconstant. Bacteria were identified in 4 cases in the absence of antibiotics and lesions of chronic osteomyelitis were observed in every case. Antibiotics were administered by intravenous injection for 3 to 7 weeks, then orally for 1.5 to 3 months. Good functional and infectious results were obtained in 4 patients, while the remaining patient presented posterior instability. CONCLUSION: Postoperative pubic osteomyelitis is an infectious disease. Acute osteomyelitis, which can be treated by antibiotics in the absence of a collection and bone sequestrum, is distinguished from chronic osteomyelitis, in which every effort must be made to identify the bacteria responsible. Infected tissues must be widely excised in combination with prolonged antibiotic therapy. Posterior instability is the main complication.