A Simplified HAART Regimen with Raltegravir and Lamivudine, and Pharmacokinetic Interactions with a Combined Immunosuppressive Therapy with Tacrolimus and Everolimus in an HIV/HCV/HBV/HDV Patient after Liver Transplantation.

In this case report, we examine the impact of a simplified two-drug highly active antiretroviral therapy (HAART) regimen of raltegravir and lamivudine in a patient co-infected with human immunodeficiency virus (HIV) and hepatitis C, D and B viruses (HCV/HDV/HBV) under immunosuppressive therapy after liver transplantation. Pharmacokinetic interactions between integrase inhibitors and immunosuppressant drugs are described. Raltegravir, the first integrase inhibitor, associated with lamivudine, was introduced because its metabolism does not interfere with immunosuppressant therapy. During post-orthotopic liver transplantation follow-up, the patient's transaminases level increased and his antiretroviral therapy (HAART) of tenofovir/emtricitabine and fosamprenavir was changed, due to suspected drug toxicity. After seven months of follow-up, the patient showed good tolerance, good viro-immunological control with undetectable HIV viraemia and stable concentrations of immunosuppressive drugs. This case indicates that the combination of raltegravir and lamivudine is an optimal and effective strategy because it resulted in an important reduction of hepatic transaminases in a patient with very critical clinical conditions.

Sustained increase of serum creatine phosphokinase levels and progressive muscle abnormalities associated with raltegravir use during 32-week follow-up in an HIV-1 experienced patient on simplified HAART regimen, intolerant to protease inhibitors and abacavir: a case report.

Sustained increase of serum creatine phosphokinase (CPK) concentrations and muscle abnormalities have been reported in patients taking raltegravir (RAL). In this report, we describe a case of sustained and asymptomatic increase of serum CPK concentrations associated with raltegravir, zidovudine, and lamivudine in an HIV-1 experienced patient with intolerance to protease inhibitor, abacavir and penicillin during 32 weeks of continuous drug monitoring.

Sustained increase of serum creatine phosphokinase levels and progressive muscle abnormalities associated with raltegravir use during a 32-week follow-up in an HIV-1 experienced patient on simplified HAART regimen, intolerant to protease inhibitors and abacavir: a case report / Aumento sostenido de los niveles de creatina fosfoquinasa sérica y las anormalidades musculares progresivas asociadas con el uso de raltegravir durante un seguimiento de 32 semanas en un paciente de VIH-1 experimentado en régimen de terapia TAAA simplificada, con intolerancia a los inhibidores de proteasa y abacavir: un reporte de caso

Sustained increase of serum creatine phosphokinase (CPK) concentrations and muscle abnormalities have been reported in patients taking raltegravir (RAL). In this report, we describe a case of sustained and asymptomatic increase of serum CPK concentrations associated with raltegravir, zidovudine, and lamivudine in an HIV-1 experienced patient with intolerance to protease inhibitor, abacavir and pencillin during 32 weeks of continuous drug monitoring.

Un aumento sostenido de las concentraciones de creatina fosfoquinasa sérica (CPK) y las anormalidades musculares ha sido reportado en relación con pacientes que toman raltegravir (RAL). En este reporte, describimos un caso de aumento sostenido y asintomático de concentraciones séricas de CPK asociadas con raltegravir, zidovudina y lamivudina en un paciente experimentado de VIH-1 con intolerancia al inhibidor de la proteasa, al abacavir y la penicilina durante 32 semanas de monitoreo farmacológico continuo.

Virological failure at one year in triple-class experienced patients switching to raltegravir-based regimens is not predicted by baseline factors.

We evaluated rates and determinants of virological failure in triple-class experienced patients receiving raltegravir-based regimens from a national observational study over 48 weeks, defined by any one of the following: (1) no HIV-RNA suppression to undetectable levels (<50 copies/mL) during follow-up; (2) detectable viral load after obtaining undetectable levels; and (3) leaving the study before 48 weeks. Among 101 eligible patients, 26 (25.7%; 95% CI 17.2-34.2) had virological failure. No significant differences between patients with and without virological failure were observed for gender, age, route of transmission, baseline CD4/HIV-RNA, CDC group, hepatitis B or C co-infections, resistance (based on the last genotype available), type and number of concomitant drug classes, concomitant use of darunavir, atazanavir, etravirine, enfuvirtide or maraviroc, and health-related quality-of-life measures. A high rate of treatment response was observed. The analyses did not identify any baseline factor associated with failure, including resistance status. Even if we cannot exclude the presence of pre-existing minority resistant variants not captured by genotypic tests, the lack of baseline predictors of failure suggests the need to monitor patients closely during follow up for other factors, such as potential drug interactions and reduced levels of adherence, which may favour virological failure.

Antimicrobial properties of distinctin in an experimental model of MRSA-infected wounds.

The aim of this study was to evaluate the efficacy of distinctin in the management of cutaneous methicillin-resistant Staphylococcus aureus (MRSA) wound infections in an experimental mouse model. Wounds, made in the panniculus carnosus of BALB/c mice, were inoculated with 5 × 10(7) colony-forming units (CFU) of MRSA. Mice were treated with topical distinctin (1 mg/kg of body weight), topical teicoplanin (7 mg/kg of body weight), intraperitoneal teicoplanin (7 mg/kg of body weight); topical teicoplanin and daily intraperitoneal teicoplanin; topical distinctin and daily intraperitoneal teicoplanin. Bacterial cultures of excised tissues and histological examination of microvessel density and of vascular endothelial growth factor (VEGF) expression were studied. It was found that topical distinctin combined with parenteral teicoplanin inhibited bacterial growth to levels comparable with those observed in uninfected animals. Wounded areas of animals treated with distinctin were characterized by a more mature granulation tissue, with a more organized and denser type of connective tissue, compared to mice treated only with teicoplanin. Treatment with topical distinctin had a significant impact on VEGF expression and microvessel density. The combined use of distinctin with teicoplanin may be useful in the management of infected wounds by significantly inhibiting bacterial growth and accelerating the repair process.

In vitro activity and in vivo efficacy of tigecycline alone and in combination with daptomycin and rifampin against Gram-positive cocci isolated from surgical wound infection.

The aim of this work was to determine the in vitro activity of tigecycline and its bactericidal effect for a large number of Gram-positive cocci, as well as to investigate its in vitro interaction with six clinically used antibiotics. In vivo, a wound model was established through the panniculus carnosus of BALB/c mice, and then inoculated with 5 × 10(7) colony-forming units (CFU) of Staphylococcus aureus or Enterococcus faecalis. For each bacterial strain, the study included an infected or non-infected group that did not receive any treatment, three groups singly treated with tigecycline, rifampin, and daptomycin, and two groups that received tigecycline treatment plus rifampin or daptomycin. In the in vitro studies, tigecycline, daptomycin, and teicoplanin were active against all of the 48 Gram-positive isolates. The combination of tigecycline with rifampicin and daptomycin was synergistic against S. aureus and Enterococcus spp. In the in vivo studies, all groups treated with single drugs showed statistically significant results compared to the control group. The two groups treated with a combination of drugs showed the highest antimicrobial efficacy. In conclusion, our results suggested a strong activity of tigecycline alone and in combination with other antimicrobial agents against multi-resistant Gram-positive organisms isolated from wound infections.

Effectiveness of antimicrobial photodynamic therapy with a single treatment of RLP068/Cl in an experimental model of Staphylococcus aureus wound infection.

BACKGROUND: Chronic leg ulceration is a common health problem. It is well known that a clinically relevant bacterial load in chronic cutaneous wounds interferes significantly with the normal process of healing. Staphylococcus aureus is the most important representative of the staphylococcal group which causes clinically relevant infections within immunocompetent patients. OBJECTIVES: To investigate the efficacy of a single treatment of antimicrobial photodynamic therapy (APDT) with RLP068/Cl in a mouse model of a surgical wound infection induced with a methicillin-resistant strain of S. aureus (MRSA). METHODS: Wounds, established through the panniculus carnosus of BALB/c and CD1 mice, were inoculated with 5 x 10(7) c.f.u. of MRSA. Mice were randomized into four groups respectively receiving no treatment, APDT with placebo, APDT with a new phthalocyanine derivative (RLP068/Cl) and intraperitoneal teicoplanin. RESULTS: On day 2 from infection, a strong reduction of bacterial counts (≈ 3 logs) was observed in mice treated with RLP068/Cl in comparison with infected untreated mice. On day 9 from infection, a comparable and significant (≈ 2 logs) reduction of bacterial counts was found in mice treated with RLP068/Cl or with teicoplanin. At this time, histological examinations revealed that wounds treated with RLP068/Cl showed a complete re-epithelialization with a continuous epithelial lining. CONCLUSIONS: The results of the in vivo study demonstrated that APDT with RLP068/Cl may be useful in the management of chronic infected wounds, accelerating the repair process through a significant bacterial inhibition.

In vitro activity of the lipopeptide PAL-Lys-Lys-NH2, alone and in combination with antifungal agents, against clinical isolates of Candida spp.

Candida albicans is known to be the organism most often associated with serious fungal infection, but other Candida spp. are emerging as clinical pathogens associated with opportunistic infections. Among antimycotic treatments, increasing attention is currently given to anti-infective drugs based upon naturally occurring peptides, such as the short lipopeptide palmitoyl PAL-Lys-Lys-NH2 (PAL). The aim of this study is to evaluate the activity of this peptide compared to the traditional antifungal agents Fluconazole (FLU), amphotericin B (AMB) and caspofungin (CAS) on Candida spp. 24 clinical isolates of Candida spp. were tested against PAL, FLU, AMB and CAS using in vitro susceptibility tests, time killing and checkerboard assay. All of the drugs studied showed good activity against clinical isolates of candida; in particular CAS and AMB which have MICs value lower than PAL and FLU. Moreover we observed synergistic interactions for PAL/FLU (81.25%), PAL/AMB (75%) and particularly for PAL/CAS (87.5). We think that our results are interesting since synergy between PAL and CAS might be useful in clinic trails to treat invasive fungal infections.

Daptomycin and rifampin alone and in combination prevent vascular graft biofilm formation and emergence of antibiotic resistance in a subcutaneous rat pouch model of staphylococcal infection.

OBJECTIVE: To investigate the efficacy of daptomycin and rifampin either alone or in combination in preventing prosthesis biofilm in a rat model of staphylococcal vascular graft infection. DESIGN: Prospective, randomised, controlled animal study. MATERIALS: Graft infections were established in the back subcutaneous tissue of adult male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with 2×10(7) colony forming units of Staphylococcus aureus, strain Smith diffuse. METHODS: The study included a control group, a contaminated group that did not receive any antibiotic prophylaxis and three contaminated groups that received intra-peritoneal daptomycin, rifampin-soaked graft and daptomycin plus rifampin-soaked graft, respectively. Each group included 15 animals. The infection burden was evaluated by using sonication and quantitative agar culture. Moreover, an in vitro antibiotic susceptibility assay for S. aureus biofilms was performed to elucidate the same activity. RESULTS: When tested alone, daptomycin and rifampin showed good efficacies. Their combination showed efficacies significantly higher than that of each single compound. The in vitro studies showed that minimum inhibitory concentration and minimum bactericidal concentration values for daptomycin were lower in presence of rifampin. Daptomycin prevented the emergence of rifampin resistance. CONCLUSION: Daptomycin is an important candidate for prevention of staphylococcal biofilm-related infection and rifampin could serve as an interesting anti-staphylococcal antibiotic enhancer.

In vitro activity of Tachyplesin III alone and in combination with terbinafine against clinical isolates of dermatophytes.

Aim of our study was to investigate the in vitro effects of Tachyplesin III (TP), a potent disulfide-linked peptide, in dermatophytes infections, with respect to or in combination with terbinafine (TERB), against 20 clinical isolates of dermatophytes belonging to four species. A broth microdilution method following the CLSI recommendations (M38-A) was used for testing drugs alone and in combination. TERB MICs were significantly lower than those observed for TP (p<0.001). Testing for antifungal agents in combination was performed for TERB with TP for all the 20 isolates. TERB activity in combination with TP showed indifferent activity for 14 of the 20 isolates (70%); synergic activity for 6 of the 20 isolates (30%); no antagonistic activity was observed. Further experiments were conducted with Microsporum canis 133, Trichophyton rubrum 62 and Trichophyton mentagrophytes 91 for fungal biomass. TP and TERB did not show a significant growth reduction compared to the control against T. mentagrophytes and T. rubrum. A significant difference of growth reduction both for TP and TERB compared to controls was observed for M. canis (p<0.01). In conclusion our study demonstrated that Tachyplesin III has potential activity against dermatophytes. In addition, we observed that the in vitro activity of Tachyplesin III can be enhanced upon combination with terbinafine. Synergy could permit lower doses of the individual antifungal agents to be used more effectively and/or safely.

In vitro activity of the lipopeptide derivative (Pal-Lys-Lys-NH), alone and in combination with antifungal agents, against clinical isolates of dermatophytes.

BACKGROUND: An increasing number of antimycotics have become available for the treatment of dermatophytoses; however, there are reports suggesting recalcitrance to therapy or resistance of a dermatophyte against conventional treatment. Lipopeptides represent novel therapeutic drugs with a new mode of action. OBJECTIVES: The aim of this study was to investigate the in vitro effects of the lipopeptide Pal-Lys-Lys-NH(2) (PAL) alone and in combination with standard antifungal agents, such as fluconazole (FLU), itraconazole (ITRA) and terbinafine (TER) against 24 clinical isolates of dermatophytes belonging to four species. METHODS: A broth microdilution method following the Clinical and Laboratory Standards Institute recommendations (M38-A) was used for testing drugs alone and in combination. RESULTS: PAL minimum inhibitory concentrations (MICs) ranged from < or = 0.25 to > 16 microg mL(-1) and they were similar to those of FLU and higher than those of either ITRA or TER. Synergy, defined as a fractional inhibitory concentration (FIC) index of < or = 0.50, was observed in 67%, 52% and 15% of PAL/ITRA, PAL/TER and PAL/FLU interactions, respectively. None of these combinations yielded antagonistic interactions (FIC index > 4). When synergy was not achieved, there was still a decrease in the MIC of one or both drugs used in the combination. CONCLUSIONS: Our study demonstrates that PAL has potential activity against dermatophytes. In addition, the in vitro activity of PAL can be enhanced upon combination with standard drugs. This lipopeptide applied in the form of lacquer, spray or ointment, could represent an interesting new therapy, particularly when combined with conventional treatment in recalcitrant or resistant dermatophyte infections.

Suppression of biofilm related, device-associated infections by staphylococcal quorum sensing inhibitors.

Staphylococcal spp. are notorious for causing biofilm-related device-associated infections, leading to tens of thousands of deaths per year. In this paper, we review quorum sensing inhibitors as potential therapeutics for even the most persistent infections. The animal models reviewed are subcutaneous graft, central venous catheter (CVC), ureteral stent and wound models, and a wound case study. The therapeutic approaches reviewed are the use of RNAIII inhibiting peptide (RIP) and its non-peptide analog. These have been shown to prevent or treat infections caused by any staphylococcal strain tested, including antibiotic-resistant strains like CA-MRSA USA300.

In-vitro activity of the synthetic protegrin IB-367 alone and in combination with antifungal agents against clinical isolates of Candida spp.

The in vitro activity of the peptide IB-367, alone or combined with either fluconazole (FLU) or amphotericin B (AMB), was investigated against 25 Candida isolates belonging to five species. IB-367 minimum inhibitory concentrations (MICs) ranged from 2.0 to 32 microg/ml and it was active against both FLU-susceptible and - resistant isolates. A rapid fungicidal activity was observed. Synergism was documented in 41.6% and 44% of IB-367/FLU and IB-367/AMB interactions, respectively. Antagonism was never observed. The broad antifungal activity and the positive interactions with AMB and FLU suggest that IB-367 represents a promising candidate against infections due to Candida spp.

RNAIII-inhibiting peptide and/or nisin inhibit experimental vascular graft infection with methicillin-susceptible and methicillin-resistant Staphylococcus epidermidis.

OBJECTIVE: To investigate the efficacy of RNAIII-inhibiting peptide (RIP) and nisin as prophylactic agents in a rat model of vascular graft infection. DESIGN: Prospective, randomized, controlled animal study. MATERIALS: Two hundred and twenty adult male Wistar rats. Staphylococcus epidermidis ATCC 12228 and one clinical isolate of methicillin-resistant S. epidermidis. Drugs: RIP, nisin and rifampin. METHODS: Graft infections were established in the dorsal subcutaneous tissue by implantation of 1 cm(2) sterile Dacron grafts, followed by topical bacterial inoculation: grafts were retrieved at 7 days. The study included a control group (without inoculation) and two series composed of five groups for each staphylococcal strain: one contaminated group that did not receive any antibiotic prophylaxis, three contaminated groups that received grafts soaked with 10 mg/l RIP, 10 mg/l nisin, 10 mg/l rifampin, or RIP+nisin. The main outcome measure was the extent of bacterial at graft harvest. RESULTS: The bacterial counts for methicillin-resistant S. epidermidis on explanted grafts were 6.1+/-2.8x10(2), 7.8+/-3.0x10(3) and 5.5+/-2.9x10(4) for RIP, nisin and rifampin, respectively. RIP and nisin used in combination reduced the bacterial count to <10. The results for S. epidermidis were similar. CONCLUSIONS: RIP and nisin could be used in combination to coat medical devices to prevent drug resistant S. epidermidis infections.

Antiendotoxin activity of antimicrobial peptides and glycopeptides.

An animal study was performed to investigate the efficacy of two glycopeptides and two cationic peptides in the prevention of lethality in a septic shock rat model. Adult Wistar rats were given an intraperitoneal injection of 2x10(10) CFU of Escherichia coli ATCC 25922, with the exception of an uninfected control group (C0). Animals were randomized to receive, immediately after bacterial challenge, intraperitoneally isotonic sodium chloride solution (control group C1), 3 mg/Kg teicoplanin (group 1), 7 mg/Kg vancomycin (group 2), 1 mg/Kg colistin (group 3), 1 mg/Kg buforin II (group 4), or 60 mg/Kg piperacillin (group C(PIP)). In addition, four groups (1a, 2a, 3a, and 4a) received the above mentioned drugs in combination with piperacillin. All compounds and combinations significantly reduced the lethality and the number of E. coli in abdominal fluid compared with C1 group, with the exception of the glycopeptides. Colistin and buforin II combined with piperacillin significantly decreased the lethality compared with piperacillin alone. Finally, colistin, buforin II, and teicoplanin significantly reduced plasma endotoxin concentration in comparison with piperacillin and saline treatment. Antimicrobial peptides and teicoplanin act as antiendotoxin agents and enhance the efficacy of piperacillin.

Administration of protegrin peptide IB-367 to prevent endotoxin induced mortality in bile duct ligated rats.

BACKGROUND: Postoperative morbidity in patients with obstructive jaundice remains high because of increased susceptibility to endotoxin and the inflammatory cascade. AIMS: An experimental study was designed to investigate the efficacy of protegrin peptide IB-367, an antimicrobial positively charged peptide, in neutralising Escherichia coli 0111:B4 lipopolysaccharide (LPS) in bile duct ligated rats. METHODS: Adult male Wistar rats were injected intraperitoneally with 2 mg/kg E coli 0111:B4 LPS one week after sham operation or bile duct ligation (BDL). Six groups were studied: sham with placebo, sham with 120 mg/kg tazobactam-piperacillin (TZP), sham with 1 mg/kg IB-367, BDL with placebo, BDL with 120 mg/kg TZP, and BDL with 1 mg/kg IB-367. RESULTS: Main outcome measures were: endotoxin and tumour necrosis factor alpha (TNF-alpha) concentrations in plasma, evidence of bacterial translocation in blood and peritoneum, and lethality. After LPS, TNF-alpha plasma levels were significantly higher in BDL rats compared with sham operated animals. IB-367 caused a significant reduction in plasma endotoxin and TNF-alpha concentrations compared with placebo and TZP treated groups. In contrast, both TZP and IB-367 significantly reduced bacterial growth compared with saline treatment. Finally, LPS induced 60% and 55% lethality in BDL placebo and TZP treated rats and no lethality in sham operated rats, while only IB-367 significantly reduced lethality to 10%. CONCLUSIONS: By virtue of its dual antimicrobial and antiendotoxin properties, IB-367 could be an interesting compound to inhibit bacterial translocation and endotoxin release in obstructive jaundice.

Quinupristin/dalfopristin bonding in combination with intraperitoneal antibiotics prevent infection of knitted polyester graft material in a subcutaneous rat pouch model infected with resistant Staphylococcus epidermidis.

OBJECTIVE: to investigate the efficacy of quinupristin/dalfopristin in the prevention of prosthetic graft infection in a rat subcutaneous pouch model. METHODS: graft infections were established in the subcutaneous tissue of 140 male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with Staphylococcus epidermidis with intermediate resistance to glycopeptides. The study included one group without contamination, one contaminated group without prophylaxis, one contaminated group that received 50mg/l quinupristin/dalfopristin-soaked graft, one contaminated group that received 10mg/kg intraperitoneal levofloxacin, one contaminated group that received 3mg/kg intraperitoneal doxycycline, and two contaminated groups that received 50mg/l quinupristin/dalfopristin-soaked plus 10mg/kg intraperitoneal levofloxacin or 3mg/kg intraperitoneal doxycycline. Each group included 20 animals. The grafts were removed after 7 days and evaluated by quantitative culture. RESULTS: quinupristin/dalfopristin showed a significantly higher efficacy than levofloxacin and doxycycline, even though quantitative graft cultures for rats that received only quinupristin/dalfopristin-soaked graft showed bacterial growth. Otherwise, the efficacy of levofloxacin was similar to that of doxycycline. Only the group treated with quinupristin/dalfopristin combined with levofloxacin or doxycycline showed no evidence of staphylococcal infection. CONCLUSIONS: quinupristin/dalfopristin as adjunctive topical antibiotic prophylaxis can be useful for the prevention of vascular graft infections caused by staphylococcal strains with high levels of resistance.

Antiseptic compounds still active against bacterial strains isolated from surgical wound infections despite increasing antibiotic resistance.

The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated during this 6-year study.

Therapeutic efficacy of the polymyxin-like peptide ranalexin in an experimental model of endotoxemia.

BACKGROUND: A rat model was used to investigate the efficacy of a polycationic peptide, the polymyxin-like ranalexin, in the prevention of lethality in a rat model of septic shock. The effect of ranalexin was compared with those of polymyxin B and imipenem. METHODS: Adult male Wistar rats (weight range: 250-300 g) were used for all the experiments. The study included five groups: an uninfected control group C(0), an untreated control group C(1), and three drug-treated groups that received 1 mg/kg ranalexin (group 2), 20 mg/kg imipenem (group 3), and 3 mg/kg polymyxin B (group 4). Rats, with the exception of the uninfected control group (C(0)), were given an intraperitoneal injection of 2 x 10(10) colony-forming units of Escherichia coli. Each group included 15 animals. Bacterial growth in abdominal exudate and plasma; endotoxin and tumor necrosis factor alpha (TNF-alpha) concentrations in plasma, and mortality were evaluated. RESULTS: Results were evaluated 48 h after inoculation. Ranalexin, imipenem, and polymyxin B significantly reduced the lethality (survival was 93.3, 80.0, and 93.3%, respectively) and the growth of E. coli both in abdominal fluid and plasma compared with saline treatment. Ranalexin showed higher antimicrobial activity than polymyxin B and imipenem and, at the same time, exhibited an antiendotoxin activity similar to that of polymyxin B (< or =0.015 EU/mL). Finally, ranalexin and polymyxin B significantly reduced plasma TNF-alpha levels (< or =4 pg/mL). CONCLUSION: Monodose ranalexin treatment prevents bacterial growth, endotoxemia, and mortality in rats with septic shock.