High silver concentrations in biological samples following different exposures: Two case reports.

BACKGROUND: Silver is used in various industrial applications, but also in confectioneries and for therapeutic use due to its antibiotic properties. Its toxicity is not well documented and most often only in the context of professional exposure. AIM: Here we report two cases of high silver concentrations in biological samples in two women: the first patient presented grey marks around her cuticles, probably due to her consumption of silvered sweets and the second patient presented agranulocytosis and thrombocytopenia occurring within 24 h after the topical application of a cream containing sulfadiazine and silver to burns over a large surface area. METHODS: Silver concentrations were determined in blood and urine samples and sweets using inductively coupled plasma- mass spectrometry (ICP-MS). RESULTS: The silver concentrations were elevated compared to population reference values and confirmed the hypotheses for the patients: the significant consumption of sweets coated with silver nanoparticles and the topical application of a cream containing silver to burns over a large area. DISCUSSION-CONCLUSION: After initial questioning by the dermatologist, Patient 1 explained that she consumed more than 30 bags of the sweets per year. She decreased her consumption of the sweets and the control performed one year later showed a plasma silver concentration of 1.5 µg/L. For Patient 2, the absorption of silver through burns over a large area appeared relatively significant, whereas it is very low through undamaged skin. The haematological cells counts returned to normal levels quickly and no other major effects were highlighted. To apply these findings to a larger population, further investigation to determine sulfadiazine and silver concentrations in plasma and urine have been initiated in a cohort of patients with burns over a large area.

Influenza vaccine effectiveness: best practice and current limitations of the screening method and their implications for the clinic.

Is there a role for the screening method in estimating influenza vaccine effectiveness (VE)? The answer is yes, but the simplicity of the method used has raised concerns about its validity, and several cautions should be noted. The screening method provides an approximation of influenza VE by comparing the proportion of cases vaccinated (PCV) with the proportion of persons vaccinated (PPV) in the general population. This method has an important disadvantage: VE estimation could be inaccurate if the values for PCV and PPV are drawn from different populations, but it has an important strength, compared with other observational studies, in providing an early indication of VE in the field. Thus, when an infrastructure, such as routine surveillance, is in place to collect robust PCV values, and PPV can be obtained from routine vaccine uptake monitoring systems, the screening method can provide early estimates of influenza VE in target groups.

The raltitrexed-vinorelbine combination: a phase I pharmacokinetic and pharmacodynamic trial in advanced breast cancer.

PURPOSE: Combinations of vinorelbine (VRB) and drugs targeting thymidylate synthase (TS) such as 5-fluorouracil (5-FU) have proven clinical efficacy in the management of advanced breast cancer. Raltitrexed (RTX) is a recent TS inhibitor which shows advantages over 5-FU in terms of a lower incidence of toxicity along with a simpler administration schedule. We conducted a phase I trial of the VRB-RTX combination in 12 patients with advanced breast cancer. MATERIALS AND METHODS: Most of the patients were refractory to taxane-anthracycline combination therapy. Their median age was 51 years (range 33-70 years). RTX was given on day 1 and VRB on days 1 and 5 on a 3-week cycle. Three dose levels were initially planned with VRB and RTX increasing from 22.5 to 25 mg/m(2) and from 2.5 to 3 mg/m(2), respectively. RESULTS: From a total of 50 cycles (mean 4 cycles per patient, range 1-11), the maximal tolerated dose (MTD) was reached at VRB 25 mg/m(2) and RTX 3 mg/m(2) with grade 3-4 neutropenia as the dose-limiting toxicity (7/16 cycles and 3/5 patients at the MTD). Nine pretreated patients were evaluable for treatment efficacy and three of these showed an objective response (one complete response, two partial responses; mean duration 26 weeks, range 17-38 weeks). Pharmacokinetic follow-up was done for both drugs (RTX by LC-MS-MS and VRB by HPLC-UV detection). There was no interaction between RTX and VRB pharmacokinetics since the VRB AUC was not significantly modified between day 1 and day 5. There was no relationship between RTX AUC and hematological toxicity. In contrast, there was a highly significant relationship between the mean VRB AUC (days 1-5) and the absolute neutrophil count decrease (Emax model, Hill constant=4.38+/-2.59, EC(50)=508+/-53.2 micro g.h/l, r=0.75, P=0.0013). A similar relationship was noted for the platelet decrease but at the limit of statistical significance. CONCLUSIONS: The VRB-RTX combination appears to be a valuable treatment option in second-line treatment of advanced breast cancer. It is deliverable on an outpatient basis, shows an acceptable toxicity profile potentially manageable by VRB pharmacokinetic follow-up, and has promising antitumor activity in taxane-anthracycline-refractory patients. The recommended dose for further studies is VRB 22.5 mg/m(2) and RTX 3 mg/m(2).