Faecal pharmacokinetics of orally administered vancomycin in patients with suspected Clostridium difficile infection

<p>Abstract</p> <p>Background</p> <p>Oral vancomycin (125 mg qid) is recommended as treatment of severe <it>Clostridium difficile </it>infection (CDI). Higher doses (250 or 500 mg qid) are sometimes recommended for patients with very severe CDI, without supporting clinical evidence. We wished to determine to what extent faecal levels of vancomycin vary according to diarrhoea severity and dosage, and whether it is rational to administer high-dose vancomycin to selected patients.</p> <p>Methods</p> <p>We recruited hospitalized adults suspected to have CDI for whom oral vancomycin (125, 250 or 500 mg qid) had been initiated. Faeces were collected up to 3 times/day and levels were measured with the AxSYM fluorescence polarization immunoassay.</p> <p>Results</p> <p>Fifteen patients (9 with confirmed CDI) were treated with oral vancomycin. Patients with ≥4 stools daily presented lower faecal vancomycin levels than those with a lower frequency. Higher doses of oral vancomycin (250 mg or 500 mg qid) led to consistently higher faecal levels (> 2000 mg/L), which were 3 orders of magnitude higher than the MIC₉₀of vancomycin against <it>C. difficile</it>. One patient receiving 125 mg qid had levels below 50 mg/L during the first day of treatment.</p> <p>Conclusions</p> <p>Faecal levels of vancomycin are proportional to the dosage administered and, even in patients with increased stool frequency, much higher than the MIC₉₀. Patients given the standard 125 mg qid dosage might have low faecal levels during the first day of treatment. A loading dose of 250 mg or 500 mg qid during the first 24-48 hours followed by the standard dosage should be evaluated in larger studies, since it might be less disruptive to the colonic flora and save unnecessary costs.</p

Human African trypanosomiasis: diagnosis, relapse and survival after severe melarsoprol-induced encephalopathy.

We describe a case of human African trypanosomiasis with a number of unusual features. The clinical presentation was subacute, but the infection was shown to be due to Trypanosoma brucei rhodesiense. The infection relapsed twice following treatment and the patient developed a melarsoprol-associated encephalopathy. Magnetic resonance imaging (MRI) findings were suggestive of microhaemorrhages, well described in autopsy studies of encephalopathy but never before shown on MRI. The patient survived severe encephalopathy with a locked-in syndrome. Our decision to provide ongoing life support may be useful to physicians treating similar cases in a setting where intensive care facilities are available

Terrestrial-Type Xenon in Meteoritic Troilite

Recently it has been realized that the isotopic composition of Xe in different phases of chondrites is not uniform and that AVCC Xe is a mixture of the different nucleogenetic components trapped in these phases1-4. We show here a similar abundance pattern for the nonradiogenic xenon isotopes in air and in meteoritic troilite (FeS), which suggests that the isotopic composition of atmospheric Xe was not produced by unique events in the history of terrestrial material but represents a particular mix of the different nucleogenetic components of Xe that was dominant in a central Fe- and S-rich region of the protoplanetary nebula5