Combined topical and oral antimicrobial therapy for the eradication of methicillin-resistant Staphylococcus aureus (MRSA) colonization in hospitalized patients.

OBJECTIVE: How to eradicate methicillin-resistant Staphylococcus aureus (MRSA) colonization in hospitalized patients is uncertain. We reviewed our experience with MRSA decolonization therapy in hospitalized patients. SETTING: An 1100-bed, university-affiliated tertiary care teaching hospital in Toronto, Ontario. DESIGN: Retrospective chart review of 207 adult inpatients with MRSA colonization hospitalized between February 1996 and March 1999. INTERVENTIONS: All patients with MRSA colonization were assessed for possible decolonization therapy with a combination of 4% chlorhexidine soap for bathing and washing, 2% mupirocin ointment applied to the anterior nares three times/day, rifampin (300 mg twice daily) and either trimethoprim/sulfamethoxazole (160 mg/800 mg twice daily) or doxycycline (100 mg twice daily). This treatment was given for seven days. RESULTS: A total of 207 hospitalized patients with MRSA colonization were identified and 103 (50%) received decolonization therapy. Patients who received decolonization therapy were less likely than untreated patients to have intravenous (P=0.004) or urinary catheters (P<0.001), or extranasal sites of colonization (P=0.001). Successful decolonization was achieved in 90% of the 43 patients who were available for at least three months of follow-up. CONCLUSIONS: Combined topical and oral antimicrobial therapy was found to be effective in eradicating MRSA colonization in selected hospitalized patients, especially those without indwelling medical devices or extranasal sites of colonization.     

Comparison of Antimicrobial Agents as Therapy for Experimental Endocarditis Caused by Methicillin-Resistant Staphylococcus aureus

We used an experimental rat model to compare the therapeutic efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin with that of vancomycin as standard therapy for infective endocarditis.Aortic endocarditis was induced in rats by insertion of a polyethylene catheter into the left ventricle, followed by intravenous inoculation of 10⁶ colony-forming units of methicillin-resistant Staphylococcus aureus 24 hours later. Forty-eight hours after bacterial challenge, intravenous antibiotic therapies were initiated. There were 6 groups of 8 rats each: uninfected control; infected, untreated control; vancomycin-treated (40 mg/kg twice daily); teicoplanin-treated (20 mg/kg twice daily after a loading dose of 40 mg/kg); linezolid-treated (75 mg/kg 3 times daily for 1 day, then 75 mg/kg twice daily); and quinupristin/dalfopristin-treated (30 mg/kg twice daily and an additional 10 mg/kg dalfopristin infusion over 6 to 12 hr daily). At the end of therapy, the aortic valve vegetations in the drug-treated rats were evaluated microbiologically.Compared with the infected, untreated group, all drug-treated groups had significantly reduced bacterial titers in the vegetations. Vancomycin, teicoplanin, and quinupristin/dalfopristin all effectively reduced the quantitative bacterial cultures of aortic valve vegetations. In addition, there was no significant difference in the comparative efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin. Vancomycin significantly reduced bacterial counts in comparison with linezolid, which was nonetheless also effective.Our experimental model showed that each of the investigated antimicrobial agents was effective in the treatment of infective endocarditis.Key words: Anti-bacterial agents/pharmacology/therapeutic use, disease models, animal, drug resistance, microbial, endocarditis, bacterial/microbiology/drug therapy, linezolid, methicillin resistance, microbial sensitivity tests, rodents, staphylococcal infections/epidemiology, Staphylococcus aureus/drug effects, teicoplanin, vancomycinInfective endocarditis is a severe disease with high morbidity and mortality rates. Staphylococcus aureus is the most frequent cause of endocarditis. Endocarditis from methicillin-resistant S. aureus (MRSA) is associated with higher mortality rates and lower bacteriologic eradication than is endocarditis from methicillin-sensitive strains. The glycopeptide antibiotic vancomycin is the standard therapy for MRSA endocarditis; however, the reported rate of treatment failure is high. In addition, staphylococci have become less susceptible to vancomycin.^1–4 Teicoplanin is a glycopeptide antibiotic that is tolerated better than vancomycin, and its half-life is longer.⁵ Although available for years in Europe, teicoplanin is not standard therapy for endocarditis and is not available at all in the United States.¹The prevalence of MRSA is increasing worldwide. Most strains are now resistant to fluoroquinolones, macrolides, tetracycline, and aminoglycosides.^6,7 There are few options for treating MRSA endocarditis and similar infections. Linezolid and quinupristin/dalfopristin (Q/D) are other agents that are active against gram-positive cocci, including MRSA. However, regarding the efficacy of these drugs in the treatment of endocarditis, data are limited and randomized controlled trials are warranted.⁸Using an experimental rodent endocarditis model, we evaluated the therapeutic efficacy of teicoplanin, linezolid, and Q/D in comparison with vancomycin in the treatment of MRSA endocarditis.     

Treatment of experimental chronic osteomyelitis due to staphylococcus aureus with vancomycin and rifampin

Vancomycin was used alone and in combination with rifampin in the treatment of experimental osteomyelitis due to Staphylococcus aureus in rabbits. Treatment with 60 mg of vancomycin/kg of body weight twice a day for 28 days was ineffective in sterilizing infected rabbit bones. Rifampin (40 mg/kg) injected once a day for 28 days sterilized 57% of infected rabbit bones. Treatment with a combination of vancomycin and rifampin for either 14 or 28 days was significantly more effective than either drug used alone, sterilizing 84% and 90%, respectively, of the infected bones of treated animals. A possible explanation for the failure of vancomycin when used alone may be that its in vitro activity against the infecting strain of S. aureus (as measured by minimal inhibitory concentrations or minimal bactericidal concentrations) was substantially less under anaerobic conditions (that is, at partial pressures of oxygen analogous to those in osteomyelitic bones) than under aerobic conditions.     

Methicillin-resistant staphylococci and their treatment in the intensive care unit

Methicillin resistance in Staphylococcus aureus (MRSA) and the coagulase-negative staphylococci (MRCNS) is widespread and continues to increase in prevalence, particularly in the health care setting. The clinical significance of methicillin resistance for patients with staphylococcal infections is not clear: studies in patients with bacteremia, pneumonia, and mediastinitis show a higher mortality with MRSA infection compared to methicillin-sensitive Staphylococcus aureus (MSSA) infection, though this may be due to underlying patient, pharmacodynamic, or microbiological differences. For serious methicillin-resistant staphylococcal infections, vancomycin-based regimens are preferred. Treatment alternatives for patients with severe methicillin-resistant infections who are unable to tolerate vancomycin include linezolid and quinupristin/dalfopristin; these agents should be considered second-line options, given the relative lack of clinical experience and the nonsignificant but consistent trends toward worse outcomes in bacteremia and pneumonia with these agents compared to vancomycin. For less severe infections, treatment options also include trimethoprim-sulfamethoxazole, or fluoroquinolones in combination with rifampin.     

Successful salvage of peritoneal catheter in unresolved methicillin-resistant staphylococcus aureus peritonitis by combination treatment with daptomycin and rifampin

Peritoneal dialysis patients are at an increased risk of Gram-positive organism infections because of disrupted skin barrier function, presence of a peritoneal catheter, and a deficient immunological system. In particular, the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections is clinically challenging. Herein, we present a case of MRSA peritonitis that showed no response to a 14-day treatment with intraperitoneal vancomycin. To overcome unresponsiveness to vancomycin, we shifted the regimen to intraperitoneal daptomycin (given every 6 h through manual peritoneal dialysate exchanges) and oral rifampin (300 mg twice daily). The peritonitis resolved without sequelae or relapse. We suggest daptomycin and rifampin as an alternative combination therapy for MRSA infections that may otherwise remain unresolved.     

Inhibitory effect of enzyme therapy and combination therapy with cyclosporin A on collagen-induced arthritis.

OBJECTIVE: There is increasing interest in the use of combination therapy for rheumatoid arthritis and in the possibility of combining the conventional drug approach with newer antirheumatic therapy. The present study investigates the efficacy of long-term prophylactic enzyme therapy and combination therapy with cyclosporin A in rats with collagen-induced arthritis. METHODS: Rats with collagen-induced arthritis were administered the following drugs: cyclosporin A (5 mg/kg/day and 10 mg/kg/day orally); a mixture of enzymes containing pure substances (bromelain, trypsin, rutin) in the same ratio as in Phlogenzym (PHL, 150 mg/kg, twice daily intrarectally); and a combination of 5 mg/kg/day cyclosporin A plus 300 mg/kg/day PHL for a period of 50 days from the immunization. Levels of serum albumin, serum nitrite/nitrate concentrations, changes in hind paw swelling and bone erosions were measured in the rats as variables of inflammation and destructive arthritis-associated changes. RESULTS: Treatment with 10 mg/kg cyclosporin A, as well as combination therapy with half dosages of cyclosporin A (5 mg/kg) plus PHL significantly inhibited both inflammation and destructive arthritis-associated changes. Significant differences in favor of combination therapy with 5 mg/kg CsA + 300 mg/kg PHL as compared to 5 mg/kg CsA alone were seen in hind paw swelling. Also, reduction of the radiographic scores was more significant in the combination therapy group. Five mg cyclosporin A or PHL alone reduced the disease markers studied to a lesser extent, and in the case of enzyme therapy this occurred at a later stage of arthritis development. CONCLUSION: Our results show the inhibitory effect of enzyme therapy on collagen-induced arthritis in rats, as well as the efficacy of cyclosporin A given in low doses in combination with enzyme therapy, which may be useful in the treatment of rheumatoid arthritis.     

Treatment of experimental chronic osteomyelitis due to Staphylococcus aureus with ampicillin/sulbactam

Ampicillin/sulbactam was used for the treatment of experimental osteomyelitis due to Staphylococcus aureus in rabbits. Treatment with 200 mg/kg (ampicillin) three times a day sterilized 40% of infected rabbit bones. The results of 4 weeks of treatment with ampicillin/sulbactam for chronic experimental staphylococcal osteomyelitis were comparable to those obtained previously with cephalothin and with oxacillin in previous studies and were not as good as those with clindamycin alone or combination therapy that included rifampin.     

Experimental osteomyelitis. V. Therapeutic trials with oxacillin and sisomicin alone and in combination

Oxacillin was used alone and in combination with sisomicin in the treatment of experimental osteomyelitis due to Staphylococcus aureus in rabbits. Within diseased bone, levels of oxacillin and sisomicin remained higher than the minimal inhibitory concentration for 2 and 6 hr, respectively, after injection of 50 mg of oxacillin/kg and 10 mg of sisomicin/kg. Treatment with 50 mg of oxacillin/kg four times daily or 50 mg/kg every 4 hr around the clock for 28 days sterilized 30% of the rabbit bones. Sisomicin (10 mg/kg) injected twice daily for 28 days sterilized only 5% of the rabbit bones. In contrast, treatment with the combination of oxacillin and sisomicin for either 14 or 28 days was significantly more effective, sterilizing 78% and 85%, respectively, of the bones of treated animals. S. Aureus isolated from bones of animals treated with sisomicin alone contained aminoglycoside-resistant microcolonies. Resistant microcolonies were not recovered from animals treated with oxacillin or with the combination of oxacillin plus sisomicin. In vitro studies of bacterial killing by each antibiotic alone and in combination showed more bacterial killing with the combination than with either agent alone; in vitro the combination prevented emergence of resistant microcolonies. Combination antibiotic therapy appears to be more effective in treatment of experimental osteomyelitis due to S. aureus than therapy with a single agent.     

Further studies of the killing of M. leprae by aminoglycosides: reduced dosage and frequency of administration

The bactericidal activity of the aminoglycoside antibiotics streptomycin and kanamycin for Mycobacterium leprae in mice was assessed, both alone and in combination with rifampin, utilizing various dosage schedules. As in previous studies, 100 mg/kg five times weekly of streptomycin and kanamycin resulted, respectively, in 96% +/- 2% and 89% +/- 6% bactericide. Reducing the dosage of streptomycin to 50 mg/kg, 25 mg/kg, and even 12.5 mg/kg resulted in less but significant bactericidal activity. Such a reduction of kanamycin dosage resulted in no significant bactericidal activity. Reducing the frequency of administration of streptomycin (100 mg/kg) to twice weekly and once weekly resulted in a decreased but still significant killing of M. leprae; for kanamycin such a reduction in frequency of administration resulted in loss of bactericidal activity. Streptomycin when combined with rifampin was found more bactericidal than either drug alone, even when each was administered only once monthly.     

Combination therapy with etanercept and anakinra in the treatment of patients with rheumatoid arthritis who have been treated unsuccessfully with methotrexate

OBJECTIVE: To determine the potential for additive or synergistic effects of combination therapy with the selective anti-tumor necrosis factor alpha agent etanercept and the anti-interleukin-1 agent anakinra. METHODS: Two hundred forty-four patients in whom rheumatoid arthritis (RA) was active despite methotrexate therapy were treated with subcutaneous etanercept only (25 mg twice weekly), full-dosage etanercept (25 mg twice weekly) plus anakinra (100 mg/day), or half-dosage etanercept (25 mg once weekly) plus anakinra (100 mg/day) for 6 months in a double-blind study at 41 centers in the US. Patients had never previously received anticytokine therapy. Patient response was measured with the American College of Rheumatology (ACR) core set criteria, a health-related quality-of-life questionnaire, and the Disease Activity Score. Safety was assessed by the number of adverse events and clinical laboratory values. Plasma concentrations of both agents and antibody formation against both agents were also assessed. RESULTS: Combination therapy with etanercept plus anakinra provided no treatment benefit over etanercept alone, regardless of the regimen, but was associated with an increased safety risk. Thirty-one percent of the patients treated with full-dosage etanercept plus anakinra achieved an ACR 50% response, compared with 41% of the patients treated with etanercept only. This result was not statistically significant (P = 0.914). The incidence of serious infections (0% for etanercept alone, 3.7-7.4% for combination therapy), injection-site reactions, and neutropenia was increased with combination therapy. Combination therapy had no effect on the pharmacokinetics or immunogenicity of either agent. CONCLUSION: Combination therapy with etanercept and anakinra provides no added benefit and an increased risk compared with etanercept alone and is not recommended for the treatment of patients with RA.     

Efficacy of vancomycin plus rifampin in experimental aortic-valve endocarditis due to methicillin-resistant Staphylococcus aureus: in vitro-in vivo correlations

Studies of in vitro and in vivo bactericidal interactions of vancomycin plus rifampin against Staphylococcus aureus have yielded conflicting results. In this study the efficacy of this drug combination in experimental endocarditis due to a methicillin-resistant strain of S. aureus was investigated. Left-sided endocarditis was induced in 84 rabbits by an infecting strain that had been found to be synergistically killed by vancomycin plus rifampin in vitro when tested by the timed-kill curve technique; in contrast, the checkerboard technique had indicated that the two drugs were antagonistic against this strain. Infected animals received no therapy, vancomycin alone (30 mg/kg per day), rifampin alone (20 mg/kg per day), or both drugs (in the same doses). The combination was significantly more effective than the single-drug regimens in terms of (1) reduction of mean methicillin-resistant S. aureus vegetation titers (P less than .05-.0005), (2) rate and incidence of sterilization of vegetations (P less than .0005), and (3) rate of "radical" cure of endocarditis (P less than .005). Vancomycin alone and vancomycin plus rifampin were equally effective in reducing mortality and sterilizing renal abscesses. The use of vancomycin prevented the in vivo development of resistance to rifampin. No evidence that rifampin exerted an antagonistic effect on the in vivo bactericidal activity of vancomycin was found.     

Bactericidal activity of antibiotics alone and in combination against Enterococcus faecalis in a pharmacodynamic model.

We evaluated the bactericidal kinetics of teicoplanin, mezlocillin, netilmicin, and ciprofloxacin alone and in dual combinations against strains of Enterococcus faecalis susceptible or resistant to ampicillin in a pharmacodynamic model reproducing in bacterial culture in active human plasma or Mueller-Hinton broth the serum kinetics of these antibiotics in humans. Killing was not different in cultures grown in plasma and those grown in broth. Antibiotics used alone had no or low bactericidal activity except for high-dose ciprofloxacin (600 mg intravenously [iv] twice daily or 750 mg orally twice daily), which achieved a 3- to 4-log reduction in colony-forming units (cfu). Netilmicin was equally active at 6 mg/kg once a day or 2 mg/kg three times daily in all combinations. No major increase in bactericidal activity was detected in any combination that included mezlocillin. Maximal synergistic killing was observed for the combination of teicoplanin plus netilmicin (both at three-times daily and once-daily dosing), which sterilized the bacterial cultures (initial inoculum, 10(6) cfu/mL). Combinations of ciprofloxacin at 600 mg iv twice daily and 750 mg orally twice daily plus either teicoplanin or netilmicin were less synergistic but equally effective in total killing as a result of the high bactericidal activity of ciprofloxacin alone.     

Effects of antisecretory agents on parietal cell structure and H/K-ATPase levels in rabbit gastric mucosain Vivo

The effect of inhibition of acid secretion on parietal cell morphology and the concentration of H,K-ATPase -subunit protein was determined by electron microscopy and western blotting. Omeprazole or famotidine alone or in combination were used. Control animals showed a morphological stimulation index (0=resting, 1.0=fully stimulated) of 0.60; omeprazole treatment (1 mg/kg, twice a day) resulted a stimulation index of 0.63, famotidine injection (20 mg/kg twice a day) an index of 0.11, famotidine infusion (0.2 mg/hr) for five days an index of 0.38, and the combination of omeprazole and famotidine injection twice a day gave an index of 0.02. No change in the frequency of degenerating or damaged parietal cells was observed in any of the groups. In control animals, the number of lysosomes was 0.9/cell, with famotidine 1.8 and with omeprazole 5.6/cell. H/K-ATPase levels fell by about 25% with omeprazole and rose by about 23% with famotidine.This work was supported by USVA-SMI and NIH grants RO1 DK 40165 and 41301.     

Equivalence trial of melarsoprol and nifurtimox monotherapy and combination therapy for the treatment of second-stage Trypanosoma brucei gambiense sleeping sickness

BACKGROUND: Treatment of second-stage sleeping sickness relies mainly on melarsoprol. Nifurtimox has been successfully used to cure melarsoprol-refractory sleeping sickness caused by Trypanosoma brucei gambiense infection. METHODS: An open, randomized trial was conducted to test for equivalence between the standard melarsoprol regimen and 3 other regimens, as follows: standard melarsoprol therapy (3 series of 3.6 mg/kg/day intravenously [iv] for 3 days, with 7-day breaks between the series); 10-day incremental-dose melarsoprol therapy (0.6 mg/kg iv on day 1, 1.2 mg/kg iv on day 2, and 1.8 mg/kg iv on days 3-10); nifurtimox monotherapy for 14 days (5 mg/kg orally 3 times per day); and consecutive 10-day melarsoprol-nifurtimox combination therapy (0.6 mg/kg iv melarsoprol on day 1, 1.2 mg/kg iv melarsoprol on day 2, and 1.2 mg/kg/day iv melarsoprol combined with oral 7.5 mg/kg nifurtimox twice a day on days 3-10). Primary outcomes were relapse, severe adverse events, and death attributed to treatment. RESULTS: A total of 278 patients were randomized. The frequency of adverse events was similar between the standard melarsoprol regimen and the other regimens. Encephalopathic syndromes occurred in all groups and caused all deaths that were likely due to treatment. Relapses (n=48) were observed only with the 3 monotherapy regimens. CONCLUSION: A consecutive 10-day low-dose melarsoprol-nifurtimox combination is more effective than the standard melarsoprol regimen.     

High frequency of thrombocytopenia in patients with acute-on-chronic liver failure treated with linezolid

BACKGROUND:Linezolid is an effective antibiotic reagent for Gram-positive bacterial infection;its most common side effect is thrombocytopenia.However,the incidence of thrombocytopenia in patients with acute-on-chronic liver failure(ACLF)who underwent linezolid therapy was unclear.The present study was to evaluate the incidence of thrombocytopenia in ACLF and non-ACLF patients treated with linezolid and the risk factors of thrombocytopenia in these patients.METHODS:Thirty-five patients with ACLF who had been subjected to intravenous administration of 600 mg linezolid every 12 hours for more than 7 days were categorized as a ACLF treatment(ACLF-T)group,72 patients without ACLF treated with the same dosage of linezolid were recruited as a non-ACLF treatment(NACLF-T)group,and 70 patients with ACLF without linezolid treatment served as an ACLF control(ACLF-C)group.The incidences of thrombocytopenia in different groups were compared at day 14.Risk factors were investigated using logistic regression analysis.RESULTS:The incidence of thrombocytopenia at day 14 was significantly higher in the ACLF-T group than in the ACLF-C group(20/35 vs 24/70,P=0.025)and in the NACLF-T group(20/35 vs 9/72,P0.001).Multivariate analysis showed that the ratio of platelet count(day 7/day 0)1(OR=10.021;P=0.012) and the baseline platelet count(OR=0.985;P=0.036)were independent risk factors of thrombocytopenia at day 14 of linezolid therapy.CONCLUSIONS:The benefits of linezolid treatment should outweigh the risk of thrombocytopenia in patients with ACLF Moreover,it is necessary to closely monitor the platelet count during linezolid therapy especially in the patients with de creased platelet count at day 7 of linezolid therapy.     

Successful conservative therapy for mediastinitis caused by multiple esophageal perforations

A 77-year-old man was admitted to our hospital on a diagnosis of acute mediastinits, 17 days after he had high fever. Computed tomography of the chest revealed an abscess cavity in the left upper mediastinum. Endoscopic examination showed multiple pin-hole perforations in the upper esophagus from 23 to 24cm distal from the incisors and drainage through the perforation. We diagnosed acute mediastinitis caused by multiple esophageal perforations of unknown etiology. We initiated conservative therapy. Oral intake was restarted on the 17th day because radiological examination showed the esophageal perforation had closed. The patient was discharged on the 36th day from admission. Although mediastinitis caused by esophageal perforation often demands surgical treatment, conservative nonoperative therapy was successful in this patient.     

Effect of 2-（8-hydroxy-6-methoxy- 1-oxo- 1H-2-benzopyran-3yl） propionic acid in combination with carboplatin on gastric carcinoma growth in vivo

AIM： To investigate the effects of 2-（8-hydroxy-6- methoxy-l-oxo-lH-2-benzopyran-3-yl） propionic acid （NM-3） alone and in combination with carboplatin on tumor growth and apoptosis in mouse models of human gastric cancer constructed by subcutaneous implantation of histologically intact tumor tissue.
METHODS： Human gastric cancer SGC-7901 tissues were implanted into the dorsal subcutis of nude mice. One week after tumors reached to a volume of 50-100 mm3 for around 1 wk, these mice were randomly divided into 8 groups （n = 10）. NM-3 was injected peritoneally at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg every other day for 5 wk, combined with carboplatin （5 mg/kg） every third day for 4 wk. As controls of combined treatment, another 4 groups of mice were injected with either NM-3 at 10 mg/kg, 20 mg/kg or 40 mg/kg, or with carboplatin alone （5 mg/kg）. The control mice received normal saline. Tumor weight, tumor growth inhibition （TGI）, and intratumoral microvessel density （MVD） were evaluated. Apoptosis of human gastric cancer was detected by TUNEL method and flow o/tometry analysis, respectively.
RESULTS： The mean tumor volume （692.40 ± 58.43 mm3, 548.30 ± 66.02 mm3, 382.13 ± 43.52 mm3） after treatment with carboplatin combined NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg was lower than that after treatment with either NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg or with carboplatin alone. Compared with the normal saline group, NM-3 administered at 10 mg/kg, 20 mg/kg or 40 mg/kg significantly reduced the tumor weight in these groups （P 〈 0.05）. Carboplatin used alone at 5 mg/kg showed minimal effects. But NM-3 in combination with carboplatin had greater effects of tumor weight than either NM-3 or carboplatin alone. NM-3 alone at the dose 10 mg/kg or in combination with carboplatin had no obvious effects on body changes. Two mice died of diarrhea in each of the two groups treated with 40 mg/kg NM-3 or with 40 mg/kg NM-3 in combination with carboplatin. A     

Linezolid vs vancomycin: analysis of two double-blind studies of patients with methicillin-resistant Staphylococcus aureus nosocomial pneumonia

OBJECTIVE: To assess the effect of baseline variables, including treatment, on outcome in patients with nosocomial pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA). DESIGN: Retrospective analysis of data from two prospective, randomized, double-blind studies. SETTING: Multinational study with 134 sites. PATIENTS: A total of 1,019 patients with suspected Gram-positive nosocomial pneumonia, including 339 patients with documented S aureus pneumonia (S aureus subset) and 160 patients with documented MRSA pneumonia (MRSA subset). INTERVENTIONS: Linezolid, 600 mg, or vancomycin, 1 g, q12h for 7 to 21 days, each with aztreonam. MEASUREMENTS AND RESULTS: Outcome was measured by survival and clinical cure rates (assessed 12 to 28 days after the end of therapy). Logistic regression analysis was used to determine the effect of treatment and other baseline variables on outcome. Kaplan-Meier survival rates for linezolid vs vancomycin were 80.0% (60 of 75 patients) vs 63.5% (54 of 85 patients) for the MRSA subset (p = 0.03). Logistic regression analysis confirmed that the survival difference favoring linezolid remained significant after adjusting for baseline variables (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.0 to 4.8; p = 0.05). Other baseline variables associated with significantly higher survival rates in MRSA pneumonia were serum creatinine levels less than or equal to two times the upper limit of normal and absence of cardiac comorbidities. Clinical cure rates for linezolid vs vancomycin (excluding indeterminate or missing outcomes) were 59.0% (36 of 61 patients) vs 35.5% (22 of 62 patients) for the MRSA subset (p < 0.01). Logistic regression analysis confirmed that the difference favoring linezolid remained significant after adjusting for baseline variables (OR, 3.3; 95% CI, 1.3 to 8.3; p = 0.01). Other baseline variables associated with significantly higher clinical cure rates in MRSA pneumonia were single-lobe pneumonia, absence of ventilator-associated pneumonia, and absence of oncologic and renal comorbidities. CONCLUSIONS: In this retrospective analysis, initial therapy with linezolid was associated with significantly better survival and clinical cure rates than was vancomycin in patients with nosocomial pneumonia due to MRSA.     

Effects of metformin and rosiglitazone in HIV-infected patients with hyperinsulinemia and elevated waist/hip ratio

OBJECTIVE: To evaluate the effects of metformin and rosiglitazone, alone or in combination, on fat distribution, insulin sensitivity, and lipids in HIV-infected patients with insulin resistance and changes in fat distribution. METHODS: A total of 105 subjects were randomly assigned to receive metformin (500 mg twice a day increasing to 1000 mg twice a day after 2 weeks) with rosiglitazone placebo (Met/P, N = 26); rosiglitazone (4 mg/day) with metformin placebo (Rosi/P, N = 27); rosiglitazone (4 mg/day) plus metformin (500 mg twice a day increasing to 1000 mg twice a day after 2 weeks; Met/Rosi, N = 25); or dual placebo (P/P, N = 27) for 16 weeks. Efficacy assessments included oral glucose tolerance testing, abdominal computed tomography, whole-body dual-energy X-ray absorptiometry, and the measurement of fasting lipids and other biochemical indices. Safety was monitored throughout. Intent-to-treat analyses were performed using non-parametric methods. RESULTS: The median insulin area under the curve (AUC) decreased significantly compared with baseline in both groups randomly assigned to rosiglitazone (Rosi/P -25.7 microIU/ml, P = 0.012; Met/Rosi -17.7 microIU/ml, P = 0.002); and tended to decrease in the Met/P group (-11.1 microIU/ml, P = 0.058). The change in AUC with combination therapy was significant compared with placebo (P = 0.032). No treatment was associated with significant changes in visceral or subcutaneous abdominal fat. Leg fat increased in subjects on Rosi/P compared with placebo (+4.8 versus -8.3%, P = 0.034). Rosiglitazone, but not metformin, increased adiponectin but also increased LDL-cholesterol and decreased HDL-cholesterol. Gastrointestinal effects occurred frequently in subjects on metformin. CONCLUSION: Both treatments improved insulin sensitivity, but neither reduced visceral fat. Rosiglitazone may increase subcutaneous fat in some individuals.     

Initial treatment of cryptococcal meningitis in AIDS

The comparison of initial treatment with amphotericin B (0.7 mg/kg/d) plus rifampin (600 mg/d) with amphotericin B (0.7 mg/kg/d) alone for 2 weeks, both followed by fluconazole (400 mg/ d) for 8 weeks in the acute treatment of cryptococcal meningitis in AIDS by an open- randomized, controlled, prospective clinical trial is reported. Twenty patients were enrolled in each group. There were no significant differences between the groups in regard to a negative CSF culture for Cryptococcus neoformans in the 2nd and 10th weeks of treatment, time until normal body temperature after treatment, number of patients who died, and persistence of high CSF pressure after completion of treatment. Elevated intracranial pressure was an important factor associated with the patients who died. These results indicate that the combination of amphotericin B plus rifampin is not superior to amphotericin B alone.