[Microbiological diagnosis of implant-associated infections : Retrospective analysis of 133 patients in an arthroplasty center]. / Mikrobiologische Diagnostik bei implantatassoziierten Infektionen : Retrospektive Analyse von 133 Patienten in einem Endoprothetikzentrum.

BACKGROUND: Because standardized microbiological cultures of puncture fluids and tissue samples often do not provide pathogen detection in implant-associated infections, sonication and polymerase chain reaction (PCR) are used additionally today. OBJECTIVES: Pathogen spectra and previous microbiological standards are examined for agreement of results using the new methods sonication and PCR. MATERIALS AND METHODS: In this descriptive, retrospective observational study, we evaluated the data of 133 patients in whom a joint prosthesis, osteosynthesis material or a spacer was removed during revision surgery with suspected implant-associated infection and sent for sonication. RESULTS: Pathogen detection was achieved by culture of peri-implant material in 40.1% and by sonication in 42.5%. In each case, coagulase-negative staphylococci were detected most frequently. Overall, the results were consistent in 71.7% of cases. In the discrepant cases, more anaerobes could be detected by sonication, especially for osteosynthesis material and knee prostheses. PCR analyses in 21 cases showed pathogen detection in 14.3% and agreement with the results of peri-implant tissue culture and sonication in 57.1% and 66.7%, respectively. CONCLUSIONS: The present results indicate a gain in sensitivity of sonication, especially for anaerobes that are difficult to grow, and a gain in specificity through sonication. PCR analyses should be reserved for specific questions.

Pharmacokinetic interactions between alitretinoin and ketoconazole or simvastatin or ciclosporin A.

BACKGROUND: Based on in vitro data with isolated cytochrome P450 (CYP) isoenzymes, alitretinoin interacts only with CYP3A4, and the potential for drug-drug interactions is considered negligible. AIM: To confirm in humans the lack of potential interactions between CYP3A4 and alitretinoin in vivo. METHODS: This was a multiple-dose, open-label, parallel-group, single-centre study, which enrolled 54 healthy male volunteers aged 18-45 years. Subjects were divided into three groups, with 18 in each group: group 1 received either alitretinoin 30 mg and ketoconazole 200 mg, group 2 alitretinoin 30 mg and simvastatin 40 mg, and group 3 alitretinoin 30 mg and ciclosporin A 300-mg. RESULTS: At the highest therapeutic dose of 30 mg, alitretinoin had no significant effect on the pharmacokinetics (PK) of ketoconazole and ciclosporin A. There was a significant but not clinically relevant effect of simvastatin on the area under the curve (AUC) of plasma concentration vs. time and on maximum plasma concentration (C(max)) after repeated administration of alitretinoin. Exposure to simvastatin concomitantly with alitretinoin was decreased by 16% for AUC and 23% for C(max). The CYP3A4 ± PgP substrates of simvastatin and ciclosporin A did not affect the single or repeated dose PK of alitretinoin. The strong CYP3A4/PgP inhibitor ketoconazole led to significant increases in both AUC and C(max) values for alitretinoin. CONCLUSIONS: Single and repeated doses of alitretinoin do not alter the PK of ciclosporin A and ketoconazole. Simvastatin levels were slightly but significantly reduced by co-administration of alitretinoin. Substrates of CYP3A4 did not affect the PK of alitretinoin. However, ketoconazole significantly increased the plasma levels of alitretinoin, therefore, co-administration with CYP3A4 inhibitors such as ketoconazole may require a dose reduction of alitretinoin.

Pharmacokinetics, efficacy and safety of alitretinoin in moderate or severe chronic hand eczema.

BACKGROUND: Recent studies have found that alitretinoin can induce clinically significant responses in subjects with severe chronic hand eczema (CHE) unresponsive to topical corticosteroids. AIMS: To assess the pharmacokinetics (PK), efficacy and safety of alitretinoin 10 or 30 mg once daily. METHODS: This was a randomized, double-blind study, which enrolled 32 subjects aged 18-75 years with CHE unresponsive to potent topical corticosteroids. Subjects received alitretinoin 10 mg (n = 16) or 30 mg (n = 16) once daily for 12 or 24 weeks. Standard PK variables [area under the curve (AUC) of plasma concentration vs. time, maximum plasma concentration (C(max)), time to maximum plasma concentration (t(max)), elimination half-life (t(1/2)), total systemic clearance (CL/F) and volume of distribution (Vd/F)] were determined for alitretinoin and metabolites. Efficacy was assessed using the Physician's Global Assessment (PGA) scale. RESULTS: Chronic administration of alitretinoin for up to 24 weeks did not result in accumulation or time-dependent changes in the disposition of alitretinoin. Exposure was found to be proportional to dose. Systemic exposure (AUC) to alitretinoin was proportional to dose for 10 and 30 mg alitretinoin; 62.8% of subjects achieved clear/almost clear hands in the 30 mg group and 12.5% in the 10 mg group. Alitretinoin was well tolerated. CONCLUSIONS: Chronic administration of alitretinoin for 12-24 weeks did not lead to accumulation or time-dependent changes in drug exposure. Alitretinoin was effective and well tolerated in the treatment of subjects with moderate or severe CHE unresponsive to potent topical corticosteroids.

Effect of mild and moderate liver disease on the pharmacokinetics of isavuconazole after intravenous and oral administration of a single dose of the prodrug BAL8557.

Isavuconazole is a promising new antifungal drug with favorable pharmacokinetic properties and excellent activity against a number of fungi. It is administered as a water-soluble prodrug (BAL8557) that is cleaved by plasma esterases to isavuconazole, which is eliminated primarily by hepatic metabolism. The objective of this investigation was to assess the effect of alcohol-related liver disease on the pharmacokinetics of isavuconazole. Subjects were 16 healthy individuals, 16 with mild liver impairment, and 16 with moderate liver impairment who were randomized to receive a single oral or intravenous dose of BAL8557 equivalent to 100 mg isavuconazole. Blood samples were collected for 21 days following drug administration, and plasma concentrations of isavuconazole, BAL8557, and the cleavage product BAL8728 were measured using high-pressure liquid chromatography coupled with tandem mass spectrometry. Following intravenous administration, the half-life of isavuconazole increased from 123 h for healthy volunteers to 224 h and 302 h for subjects with mild and moderate liver impairment, respectively. The systemic clearance of isavuconazole following intravenous administration decreased from 2.73 liters/h for healthy subjects to 1.43 liters/h for subjects with moderate liver impairment (47.6% decrease [P < 0.05]). A similar decrease (23.5%) was observed after oral administration. These results suggest that a dose adjustment may be needed when isavuconazole is used to treat fungal infections in patients with liver disease.