[Prosthetic joint infection by Candida spp.]

INTRODUCTION

Fungal periprosthetic infectionis a rare entity. The aim of this report was to review our experience in two different educational hospitals.

MATERIAL AND METHODS

patients with documented prosthetic joint infection due to Candida spp. from February 2002 to October 2010 were retrospectively reviewed. Demographics, microbiological data, treatment and outcome of each patient was recorded.

RESULTS

Ten patients, 8 women and 2 men, with a meanage of 77.7 (range 66-92) years were identified. Nine patients had previous bacterial infection, received antibiotic treatment for more than 15 days and required multiple surgeries. The most frequent species was C. albicans with 6 cases. All patients received fluconazole and surgical treatment consisted of debridement without removing the implant in 3 cases and 2-stage exchange with a spacer in 7. The first surgical and antifungal approach failed in all cases and a second debridement was necessary in one case, a resection arthroplasty in 8 and chronic suppressive treatment with fluconazol in one. After a mean follow-up of 31 (range 2-67) months, two patients were free of infection.

CONCLUSION

Prosthetic joint infection was associated with long-term antibiotic treatment and multiples previous surgeries. Treatment with fluconazol and debridement or two stage replacement with a spacer was associated with a high failure rate.

[Epidemiology and clinical presentation of Panton-Valentin leukocidin positive methicillin-resistant Staphylococcus aureus]

INTRODUCTION

the aim of our study was to review the epidemiology and clinical manifestations of infections due to Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus (PVL-MRSA).

MATERIAL AND METHODS

Medical history of patients infected by MRSA-PVL admitted to our hospital from January 2007 to July 2009 was reviewed. PVL and the type of cromosomic cassette were determined in all strains by PCR.

RESULTS

A total of 37 cases were included. Seventy percent were males and the median age was 39 years. Sixtytwo percent were Spanish, 14 (37.8%) were HIV-positive and 11 (29.7%) were homosexual. The source of the infection was the skin and soft tissue in 36 cases and pneumonia in 1. Sixteen patients were hospitalized, 5 had bacteremia and 5 developed septic metastasis. The relapse rate was 24% (9 cases). The prevalence during the study period was 11.2% of all MRSA isolated (37 out of 329). All the strains had a cromosomic cassette type IV and were susceptible to cotrimoxazole, rifampin, vancomyin, daptomycin and linezolid. The MIC of vancomycin, measured by E-test, was ≥ 1.5 mg/L in 28 out of 34 cases (82.3%).

CONCLUSIONS

Eleven percent of the MRSA strains isolated in our hospital are PVL positive. In general, skin and soft tissue infections are the most common and bacteremia or septic metastasis are frequent. In contrast to previous Spanish studies, more cases are observed in patients born in Spain and the infections are more severe.

Hepatocellular carcinoma and liver transplantation: a 12-year experience

BACKGROUND

Orthotopic liver transplantation (OLT) for patients with cirrhosis and concomitant hepatocellular carcinoma (HCC) in early stages is the treatment of choice, with an acceptable recurrence rate and excellent survival.

AIM

We sought to evaluate (1) the accuracy of preoperative imaging; (2) the impact of pre-OLT treatments on survival and recurrence; and (3) the influence of beyond Milan criteria selection on global outcomes.

METHODS

We studied a cohort of 65 patients with HCC among 300 consecutive OLTs over a single 12-year experience. We analyzed the overall outcomes of survival and recurrence, the accuracy of preoperative diagnosis and staging the influence of neoadjuvant treatment prior to OLT, and the effect on overall outcomes beyond the Milan criteria in our series.

RESULTS

The 65 transplants were performed for HCC, mostly in association with hepatitis C virus and alcoholic cirrhosis with HTP. At a mean follow-up of 40.32 months, the recurrence rate was 5.7% among the 61 HCC confirmed by histopathology. The overall survival was 30.07. Actuarial survivals at 1, 5, and 10 years were 82%, 77%, and 62%, respectively. Six retransplants occurred among the seven graft losses albeit with poor survival after the second graft. Most explants showed low pTNM stages with favorable microscopic features. Preoperative imaging tests failed to achieve an accurate diagnosis in 15.38% of the series. The role of alpha-fetoprotein (AFP) and hepatic biopsy was irrelevant. Unfavorable histopathologic factors predicted a greater recurrence rate, but had no influence on survival. Neither recurrence nor survival were modified by pre-OLT therapy.

CONCLUSIONS

In our series, AFP, hepatic biopsy, and pre-OLT treatment had limited roles. Radiological imaging techniques underestimated HCC staging and lead to a misdiagnosis to an expected degree. Despite these findings, this single institution experience with OLT for HCC showed excellent survivals with a low recurrence rate including cases of patients beyond the Milan criteria.

Atypical sarcoidosis: case reports and review of the literature

Sarcoidosis is a granulomatous disease of unknown origin, with pulmonary findings in more than 90% of patients. Extrapulmonary involvement is common and all organs can be involved (especially lymph nodes, eyes, joints, central nervous system) but it is rare to find an isolated extrapulmonary disease (less than 10% of patients). Granulomatous inflammation of the spleen and the liver is common in patients with systemic sarcoidosis, while hepatosplenic enlargement is unusual and splenic involvement rare. We report two cases of systemic sarcoidosis, that onset with splenic and hepatosplenic disease, and one case with splenic sarcoidosis without pulmonary involvement. In the first case a 53-year-old woman with mild abdominal pain underwent sonography and CT, which revealed one hypoechoic/hypodense splenic lesion. Laboratory tests were normal. In order to exclude a lymphoma, splenectomy was performed: histology revealed a sarcoid granuloma. After surgery the patient was asymptomatic and now, after two years, disease is silent. The second case is a 66-year-old woman with a recent weight loss (8 kg in two months) and alterated liver function tests (AST 61 U/l, ALT 72 U/l, Alkaline phosphatase 748 U/l, g-GT 381 U/l). Since she had a familiar history of colon cancer, abdominal US scan, abdominal CT scan and MRI were performed and showed inter-aorto-caval lymphadenopathies and discreet multiple bilobar hepatic and splenic substitutive lesions, with no signs of primary tumor. Upper and lower GI endoscopy, full gynecological workup, complete set of tumor markers, bone marrow biopsy were performed. All resulted negative for neoplasia. Small pulmonary infiltrations were observed on chest-CT scan but cytology on BAL was normal. Infections were also excluded. An exploratory laparotomy showed whitish peritoneal, hepatic and splenic nodules. The histological exam revealed chronic granulomatous lesions typical for sarcoidosis. During a two-year follow-up after the splenectomy the patient feels well without any treatment. The third patient is a 32-year-old woman with mild epigastric pain after meals. Neck-thoracic CT, bone scintigraphy and upper GI endoscopy were negative. Abdominal US and MR showed splenomegaly with multiple splenic lesions. Splenectomy was performed and histological exam showed chronic granulomatous lesions typical for sarcoidosis. Further laboratory tests were normal, except for ACE (66 UI/l). After the surgery ACE became normal and now, three years later, the patient is still asymptomatic. We conclude that hepatosplenic involvement is less rare than it is thought. It is often oligosymptomatic or accompanied with unspecific manifestations and laboratory abnormalities. The diagnosis could be difficult; in fact typical laboratory findings of sarcoidosis such as ACE, lysozyme, calcium, were not diagnostic. Ultrasonography and CT were important but the diagnosis was established only with the histological examination of suspected lesions. This latter required to differentiate liver and/or spleen sarcoidosis from tuberculosis and other infections, primary biliary cirrhosis, metastasis or malignant lymphoma.

Clinical features of familial Mediterranean fever: an Italian overview

Familial Mediterranean Fever (FMF) is the most frequent periodic febrile syndrome among the autoinflammatory syndromes (AS), nowadays considered as innate immunity disorders, characterized by absence of autoantibodies and autoreactive T lymphocytes. FMF is a hereditary autosomal recessive disorder, characterized by recurrent, self-limiting episodes of short duration (mean 24e72 h) of fever and serositis. In FMF, periodic attacks show inter- and intra-individual variability in terms of frequency and severity. Usually, they are triggered by apparently innocuous stimuli and may be preceded by a prodromal period. The Mediterranean FeVer gene (MEFV) responsible gene maps on chromosome 16 (16p13) encoding the Pyrine/Marenostrin protein. The precise pathologic mechanism is still to be definitively elucidated; however a new macromolecular complex, called inflammasome, seems to play a major role in the control of inflammation and it might be involved in the pathogenesis of FMF. The most severe long-term complication is type AA amyloidosis, causing chronic renal failure. Two types of risk factors, genetic and non-genetic, have been identified for this complication. Currently, the only effective treatment of FMF is the colchicine. New drugs in a few colchicine resistant patients are under evaluation

Gastrointestinal amyloidosis: a case of chronic diarrhoea

Amyloidosis is a rare disease caused by extracellular deposits of insoluble fibrillar proteins in various organs and tissues. There are different forms of amyloidosis distinguished by the type of protein fibrils, by the sites of deposition and by associated conditions. Gastrointestinal involvement is common both in primary and secondary amyloidosis, while isolated gastrointestinal amyloidosis is rare. We describe a case of AL amyloidosis with a gastrointestinal involvement and restrictive cardiomiopathy. A 64 year old woman came to our attention with a history of chronic diarrhoea and weight loss, associated with dysphagia, dry mouth, xerophtalmia, chronic gastritis and depression. Clinical diagnosis has been difficult because of aspecificity of symptoms that mimed other more common diseases, like gastro-paresis, epigastric discomfort, gastric or duodenal ulcers, perforation, malabsorption, intestinal pseudo-obstruction. There is an important risk of misunderstanding and diagnostic delay. Indeed in this patient a diagnosis of irritable colon syndrome was erroneously established two years before admission in our hospital. Therefore gastrointestinal amyloidosis should be considered among differential diagnoses of chronic diarrhoea and weight loss when other more common diseases have been excluded.

Cyclosporine A: good response for patients affected by autoimmune disorders and HCV infection?

INTRODUCTION

In autoimmune disorders (ADs), if Hepatitis C Virus (HCV) is present, immunosuppressive treatment could increase virus replication. Cyclosporine A (CsA), in standard therapeutic doses, has been proven able to inhibit HCV cyclophilin in vitro. Therefore CsA could improve the therapy of HCV patients with ADs.

AIM

In these patients, we started an open pilot study to evaluate the safety of 3 mg/kg CsA and the ability to reduce steroid therapy.

PATIENTS AND METHODS

Five females and 1 male were recruited; mean age 66 +/- 8 years, mean disease duration 13 +/- 5 years. Three patients are affected by Psoriasic Arthritis, 1 by Rheumatoid Arthritis, 1 by Sjogren Syndrome, and 1 by Myasthenia Gravis. None of them had chronic active hepatitis. HCV genotypes were type 2 (in 3 cases) and type 1 (in 3 cases). Patients were treated with 3 mg/kg of CsA for a period of time ranging from 6 to 12 months. The starting mean dose of prednisone was 12.5 mg/day. Liver function tests were checked monthly and serum HCV-RNA load was checked by RT-PCR before and 2 months into the therapy.

RESULTS

The prednisone dose was reduced from 12.5 mg/day to 7.5 mg/day. The aminotransferases levels were unchanged after 6 months. In patients with low HCV-RNA levels before treatment, no modifications of viral load were observed, whereas patients with increased levels at onset showed mild reduction 2 months into the treatment.

CONCLUSIONS

Immunosuppressive treatment of ADs patients with HCV infection can be safely provided with the integration of CsA.

[Potential use of bone marrow scintigraphy in suspected prosthetic hip infection evaluated with 99mTc-HMPAO-leukocytes]

AIM

To evaluate the usefulness of (99m)Tc-Sulphur colloid when combined with leukocyte scintigraphy in suspected prosthetic hip infection, comparing the results with information from (99m)Tc-HMPAO-leukocyte scintigraphy alone.

MATERIALS AND METHODS

Seventy patients (42 women, 28 men; mean age 68 +/- 13 years) with painful hip prostheses and suspicion of infection were evaluated prospectively. All patients had bone scintigraphy, (99m)Tc-HMPAO-labelled white blood cell scintigraphy and (99m)Tc-Sulphur colloid bone marrow scintigraphy. ESR and CRP levels were measured in all patients. The final diagnosis was made with microbiological findings or by clinical follow up of at least 12 months.

RESULTS

Infections were diagnosed in 12 of the 70 patients (3 coagulase-negative Staphylococcus, 2 Staphylococcus aureus, 2 Staphylococcus epidermidis, 2 enterococcus and 3 polymicrobial agents). ESR and CRP values were higher in patients with infection than in patients without infection (51.8 +/- 29.4 vs. 25.4 +/- 16.4 and 2.8 +/- 2.2 vs. 1.1 +/- 1.3, respectively; p < 0.05). Bone scintigraphy did not show a characteristic pattern to differentiate infection from aseptic loosening. The pool phase of the bone scintigraphy was positive in only 3/12 patients with infection (25 %). Sensitivity and specificity of the leukocyte scintigraphy was 83 % and 57 %, respectively. When the results of the bone marrow scintigraphy were added, these values increased to 92 % and 98 %, respectively.

CONCLUSION

Performing bone marrow scintigraphy significantly improves results when compared with leukocyte scintigraphy alone in the diagnosis of infected hip prostheses. Bone scintigraphy did not help to differentiate aseptic loosening from infection in this series.

[Methicillin-resistant Staphylococcus aureus bacteremia. Predictor factors for an isolate with a vancomycin minimal inhibitory concentration > or =2 mg/l]

A greater rate of treatment failures with vancomycin in methicillin-resistant Staphylococcus aureus (MRSA) bacteremia has been reported recently when the minimum inhibitory concentration (MIC) is > or =2 mg/l. This study has aimed to evaluate if there are clinical and/or epidemiological factors that predict isolation of a MRSA strain with MIC of vancomycin of > or =2 mg/L in the bacteremia episodes collected during a 15 year period (January 1991 to December 2005) in a tertiary urban hospital. During the study period, a total of 478 episodes of MRSA bacteremia were studied prospectively. The following clinical variables were recorded for each one: age, gender, comorbidity, previous administration of vancomycin or another antibiotic, prognosis of baseline diseases, bacteremia focus, shock, empiric antibiotic received and mortality. The MIC of vancomycin of 419 strains (88%) was determined with the E-test. In 216 (52%) of the isolations the MIC of vancomycin was 1.50 mg/L, in 110 (26%) of the cases it was < or =1 mg/l and in 93 (22%) 2 mg/l. Uni-and multivariate analyses were made, comparing the clinical variables of the patients infected by strains with MIC of vancomycin > or =2 mg/l regarding the MIC strains < or =1 mg/l. In the last 3 years of the study (2003-2005) the proportion of the strains with MIC of vancomycin > or =2 mg/l was significantly greater than those isolated with MIC < or = 1 mg/L (44 % vs 3 %; p<0.001). In the multivariate analysis, the only clinical characteristic associated independently to the isolation of a strain with MIC > or =2 mg/l was the nosocomial-acquired infection OR (95 % CI): 1.94 (1.04-3.63); p=0.04. Although the isolation of a MRSA strain with MIC of vancomycin > or =2 mg/l is more frequent in the nosocomial-acquired bacteremia episodes, in the clinical practice, it is not a useful predictive parameter because the frequency of isolation of these strains in the community is also high.

A cooperative approach for the diagnosis of the melanoma

In this work we present a decision support system for the melanoma diagnosis using individual methods and the collaboration between these methods. The system designed uses a photograph of the lesion and it makes a preprocessing task to extract the region of interest. Then, several characteristics of the image are analyzed, studying with different methods the degree of malignity; the methods used are based in Bayesian rules and in neural networks. Finally, each individual decision from each method contributes in some way to the final decision. The classification rate obtained with the cooperative approach is above 92%.

[Can we improve our results in hemodialysis? Setting quality objectives, feedback, and benchmarking]

To diminish inter centres variability in applied medical treatments, as well as in the results obtained with them, is one of the main challenges that Nephrology faces now a days. The systematic and planned use of Clinical Performance Measures (CPMs), Feedback and Benchmarking are tools that can help clinicians to reach such an objective. In this study we evaluate the consequences of applying those techniques in the results obtained in three haemodialysis units.

METHODS

we analyzed the results obtained in 311 patients dialyzed in the three units during the period 2006-2007. Established and evaluated objectives were as follows: 1.- To increase the percentage of patients with a serum calcium below 9,5 mg/dl over 70%; 2.- To increase the percentage of patients with a serum phosphorus under 5,5 mg/dl over 80%; 3.- To increase the percentage of patients with a serum PTH in between 150-300 pg/ml over 40%; 4.- To diminish the percentage of patients with a serum ferritine below 100 ng/ml under 10%, in one of the units that at the beginning of the study was not accomplishing that objective. Every three months each unit received their own results as well as the results of the two other units.

RESULTS

the percentage of patients with serum calcium below 9,5 mg/dl increased significantly in the three units (54,6%, 56,1% and 55,6% at the beginning; 87,7%, 82.9% and 75,1% at the end of the study, respectively; p<0,001). The same was observed for the percentage of patients with a serum phosphorus below 5,5 mg/dl (77,9%, 73,6% and 66,0% at the beginning; 81,7%, 78,0% and 85.9% at the end, respectively; p: not significant), and for the percentage of patients with PTH between 150-300 pg/ml (32,9%, 43,1% and 26,4% versus 47,5%, 41,4% and 39.5%, respectively; p: not significant). The percentage of patients with a serum ferritin below 100 ng/ml in unit B diminished from 30% to 5,3% (p<0,001), reaching results similar the the two other units. Mean erythropoietin (EPO) consumption during the year 2005 was 145,5+/-13,2 U/kg/week in unit A; 226,2+/-39,8 U/kg/week in unit B, and 175,5+/-13,9 U/kg/week in unit C. At the end of year 2007, mean EPO consumption was significantly lower in unit B (144,2+/-15 U/kg/week), and similar to the other two units (140+/-14,2 in unit A and 135,1+/-13,8 in unit C).

CONCLUSION

The results of this study permit to conclude that the use of QPM's and quality targets, combined with feedback and benchmarking, allows for the improvement of clinical results. Each centre should establish their own objectives, independently of the defined quality standards, so as to reach such standards or even to improve them. In this study, the three units showed a general improvement in their results, tending towards similar outcomes for the same clinical processes.

Pharmacokinetic interaction between rifampicin and ritonavir-boosted atazanavir in HIV-infected patients

BACKGROUND

Tuberculosis (TB) is a common opportunistic infection among HIV-infected people, and rifampicin is an important drug for the treatment of TB. However, administration of rifampicin in combination with antiretroviral therapy, particularly protease inhibitors, is difficult because of drug-drug interactions.

METHODS

We have performed a prospective study in three HIV-infected patients with TB treated with a rifampicin-containing regimen (rifampicin 600 mg per day) and antiretroviral therapy including only nucleoside reverse transcriptase inhibitors (NRTIs) plus atazanavir 300 mg once a day (qd) and ritonavir 100 mg qd, to evaluate whether the inducing effect of rifampicin on the drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 could be overcome by the inhibitory effect of ritonavir. A complete pharmacokinetic evaluation of the steady-state concentrations of atazanavir and ritonavir was performed.

RESULTS

In all three cases, more than 50% of the time the atazanavir level was below the minimum recommended trough plasma level (150 ng/mL according to current pharmacokinetic guidelines) to inhibit HIV wild-type replication.

CONCLUSION

These results strongly indicate that the administration of rifampicin with a combination of atazanavir 300 mg qd plus ritonavir 100 mg qd must be avoided because subtherapeutic concentrations of atazanavir are produced.

Decreasing gradient of antibiotic concentration in the lumen of catheters locked with vancomycin

The purpose of this study was to investigate if vancomycin concentration is maintained along the lumen of dialysis catheters after 48 h of lock therapy. Each lumen of nine catheters (three subclavian and six femoral) was locked with 2,500 mg/l of vancomycin for 48 h. After that period, the content of the lumen was aspirated with three different syringes of 0.4 ml each to measure the proximal, medial and distal vancomycin concentration. Vancomycin concentration was measured using a homogeneous particle-enhanced turbidimetric inhibition immunoassay. A non-parametric ANOVA, by means of a rank transformation on the antibiotic concentration, was used to assess the influence of the catheter segment (proximal, medial and distal) and the catheter type (femoral or subclavian). A significant decrease in vancomycin concentration from proximal to distal segments was observed (p < 0.001). In addition, the vancomycin concentration in subclavian catheters was significantly higher than in femoral catheters (p < 0.001). In our study there was a decreasing gradient in vancomycin concentration from proximal to distal segments of the catheter. This may explain the failure of antibiotic lock-therapy.

Epidemiology and outcome of primary community-acquired bacteremia in adult patients

We conducted this study to determine the associated factors and outcomes of community-acquired primary bacteremia (PB), to describe the most frequently isolated microorganisms, the antibiotic resistance pattern, and to guide the most appropriate antibiotic treatment. A total of 1,640 community-acquired bacteremia cases in nonneutropenic adults were consecutively enrolled from January 2003 to May 2006 and prospectively followed up. Nonconditional logistic regression methods were used with PB and death as dependent variables. Secondary bacteremia (SB) was present in 1,440 patients, and 200 (12%) cases were PB. The independent factors associated with PB were male sex (OR 1.69, 95%CI 1.27-2.25, P = 0.001) and an ultimately or rapidly fatal prognosis for an underlying disease (OR 2.48, 95%CI 1.84-3.34, P = 0.001). The most frequently isolated microorganisms in PB were E. coli and other enterobacteria (26 and 22%, respectively) and S. aureus (15%). There were 28 and 37% ciprofloxacin-resistant E. coli strains in SB and PB, respectively (P = 0.2). Mortality was significantly higher in PB cases (13 vs 8%, P = 0.04). The independent factors associated with mortality in PB were ultimately or rapidly fatal prognosis of underlying disease (OR 2.1, 95%CI 1.41-3.13, P = 0.001), lack of fever at the moment of bacteremia (OR 2.38, 95%CI 1.18-4.76, P = 0.02) and incorrect empirical antibiotic therapy (OR 2.01, 95%CI 1.22-3.33, P = 0.006). The initial empiric antibiotic treatment was more frequently incorrect in PB than in SB, and this was a predictive factor for mortality in PB. The resistance pattern of E. coli, other enterobacteria and S. aureus in every setting should guide the most appropriate empirical treatment for PB.

Microbial and clinical determinants of time-to-positivity in patients with bacteraemia

Time-to-positivity is useful in the diagnosis of catheter-related bacteraemia and as a predictor of an endovascular source in patients with Staphylococcus aureus bacteraemia. However, this parameter has been evaluated for only a limited number of microorganisms. In the present study, time-to-positivity was recorded for 1872 episodes of significant monomicrobial bacteraemia diagnosed at a teaching hospital during a 2-year period, and the associated microbial and clinical variables were investigated. According to multivariate analysis, Streptococcus pneumoniae, beta-haemolytic streptococci, Escherichia coli, Klebsiella, Enterobacter, Citrobacter and Aeromonas were characterised by fast growth, with an endovascular source, shock, liver cirrhosis and neutropenia also predicting a short time-to-positivity. For patients not receiving appropriate antibiotics, detection of Gram-positive cocci in clusters within 14 h was predictive of Staph. aureus; a time-to-positivity of >21 h ruled out the possibility that a Gram-positive organism in chains was a beta-haemolytic streptococcus or Strep. pneumoniae, and a time-to-positivity of < or =12 h meant that it was very unlikely that a Gram-negative bacillus was a non-fermenter. A time-to-positivity of < or =8 h was predictive of a non-urinary tract source in patients with E. coli bacteraemia, and detection of growth within 13 h predicted an endovascular source in those with Staph. aureus bacteraemia. In conclusion, time-to-positivity depended on the microorganism, original source and clinical variables involved. Although this measurement may provide some early clues concerning the microorganisms involved and the source of bacteraemia, its clinical impact remains to be defined.

Usefulness of teicoplanin for preventing methicillin-resistant Staphylococcus aureus infections in orthopedic surgery

In order to gather more data on the use of teicoplanin for reducing MRSA infections in high-risk populations, the present study was conducted. At a hospital in Barcelona, Spain, there was a high prevalence of MRSA infections among patients who underwent surgery for femoral neck fracture during the first 5 months of 2002 (period A) when cefuroxime was the antibiotic prophylaxis. During the following 12 months (period B) 600 mg of teicoplanin was added to cefuroxime. The rates of overall and MRSA infection during period A were 5.07 and 2.73%, respectively. Pulsed-field gel electrophoresis demonstrated there was no clonal relationship among MRSA strains. No nasal carriers of MRSA were detected among health workers. During period B the rates of overall and MRSA infection were 2.36 and 0.19%, respectively. Both rates were statistically significantly lower than those in period A (p<0.05). These results suggest teicoplanin may be useful in patients undergoing orthopedic surgery when the prevalence of MRSA is high.