Faculty Bibliography

The duration of hemodialysis (HD) sessions for the treatment of acute ethylene glycol poisoning is dependent on concentration, the operational parameters used during HD, and the presence and severity of metabolic acidosis. Ethylene glycol assays are not readily available, potentially leading to undue extension or premature termination of HD. We report a prediction model for the duration of high-efficiency HD sessions based retrospectively on a cohort study of 26 cases of acute ethylene glycol poisoning in 24 individuals treated by alcohol dehydrogenase competitive inhibitors, cofactors and HD. Two patients required HD for more than 14 days, and two died. In 19 cases, the mean ethylene glycol elimination half-life during high-efficiency HD was 165 minutes (95% confidence interval of 151-180 minutes). In a training set of 12 patients with acute ethylene glycol poisoning, using the 90th percentile half-life (195 minutes) and a target ethylene glycol concentration of 2 mmol/l (12.4 mg/dl) allowed all cases to reach a safe ethylene glycol under 3 mmol/l (18.6 mg/dl). The prediction model was then validated in a set of seven acute ethylene glycol poisonings. Thus, the HD session time in hours can be estimated using 4.7 x (Ln [the initial ethylene glycol concentration (mmol/l)/2]), provided that metabolic acidosis is corrected.

Background/UNASSIGNED:Extracorporeal treatments (ECTRs) are used for different conditions, including replacement of organ function and poisoning. Current recommendations for ECTRs in various poisonings suggest that intermittent haemodialysis (IHD) is the most efficient technique. However, the practicality of these recommendations is poorly defined in view of limited information on availability and cost worldwide. Methods/UNASSIGNED:A survey invitation to an Internet-based questionnaire was emailed between January 2014 and March 2015 to members of international societies to determine the availability, time to initiation and cost of ECTRs (including filters, dialysate, catheter, anticoagulant and nursing/physician salary). The median cost ratio of every ECTR compared with IHD performed in the same institution were presented. Results/UNASSIGNED:The view rate was estimated at 28.1% (2532/9000), the participation rate was 40.1% (1015/2532) and the completion rate was 16.0% (162/1015). Respondents originated from 89 countries, and nearly three-fourths practiced in a tertiary care centre. A total of 162 respondents provided sufficient data for in-depth analysis. IHD was the most available acute ECTR (96.9%), followed by therapeutic plasma exchange (TPE; 68.3%), continuous renal replacement therapy (CRRT; 62.9%), peritoneal dialysis (PD; 44.8%), haemoperfusion (HP; 30.9%) and liver support devices (LSDs; 14.7%). IHD, CRRT and HP were the shortest to initiate (median = 60 min). The median cost ratios of each ECTR compared with IHD were 1.7 for CRRT and HP, 2.8 for TPE, 6.5 for LSDs and 1.4 for PD (P < 0.001 for all). The median cost ratio of a 4-h IHD treatment compared with 1 day in the intensive care unit was 0.6 (P =  0.2). Conclusions/UNASSIGNED:IHD appears to be the most widely available ECTR worldwide and is at least 30% less expensive than other ECTRs. The superior efficacy of IHD for enhanced elimination, added to its lower cost and wider availability, strengthens its preference as the ECTR of choice in most cases of acute poisoning. Keywords/UNASSIGNED:costing, CRRT, EXTRIP, hemodialysis, hemoperfusion.

OBJECTIVES/OBJECTIVE:No consensus currently exists on the indications for Pneumocystis jirovecii prophylaxis in patients with inflammatory or autoimmune diseases. The main objective was to identify biomarkers associated with P. jirovecii pneumonia (PCP) in this population. METHODS:A retrospective study was carried out at Beijing Union Medical College Hospital (2003-2014). All patients with an inflammatory or autoimmune disease presenting with acute onset of fever and respiratory symptoms were included. RESULTS:<160. CONCLUSIONS:In patients with inflammatory and autoimmune conditions receiving immunosuppressive therapy, low CD3+ and CD8+ cell counts were strongly associated with PCP and its mortality. These results suggest that lymphocyte subtyping is a very useful tool to optimize the selection of patients needing prophylaxis.

We describe the case of a 52-year-old man who presented after having ingested an unknown quantity of phenytoin. Peak phenytoin concentration was 51.2 mg/L (therapeutic range 10-20 mg/L). Five days after admission, the patient became comatose and was intubated. Because of persistent toxic phenytoin levels and unchanged clinical status for 12 days, hemodialysis (HD) was prescribed to enhance elimination of phenytoin. HD was performed using a Gambro Theralite^TM filter (Baxter International Inc., Deerfield, USA), a high cut-off filter that allows the removal of molecules of up to 45 kDa. Phenytoin concentration readily decreased during the 8-hour HD treatment from 38.9 mg/L to 27.8 mg/L (28.5% decrease); during HD, phenytoin half-life was 18.5h (compared to 1109.8h before HD and 56.3h after HD), phentyoin clearance averaged 80.1 mL/min and a total of 1.1 g of phenytoin was removed. Albumin removal from the Theralite filter was most important at the beginning of HD. The high clearance of phenytoin obtained with this filter was likely due to its high surface area rather than its capacity to remove the albumin-phenytoin complex.

INTRODUCTION/BACKGROUND:Intentional dapsone intoxication can be life-threatening. There is limited data on the clinical effect of extracorporeal treatments (ECTRs) on dapsone elimination. We describe a case of severe dapsone toxicity treated with different ECTRs. CASE DETAILS/METHODS:/L 3 h after IHD-HP. The elimination half-life of dapsone was 2.0 h during IHD-HP, and 14.2 h during CVVH. Mean dapsone clearance with IHD was 62 mL/min versus 22 mL/min with CVVH. IHD removed 95.3 mg, and CVVH removed 67.8 mg over 3.8 h. No rebound occurred following ECTR cessation. The toxicokinetics of dapsone metabolites were also accelerated during ECTR. The patient was extubated after 3.5 days and discharged without sequelae after 7 days. DISCUSSION/CONCLUSIONS:Dapsone clearance was enhanced by ECTR, especially by IHD-HP. However, HP was associated with severe asymptomatic thrombocytopenia.

A recent analysis of the American Association of Poison Control Centers database, showed that poisonings from toxins not usually considered amenable to extracorporeal purification ("non-classic toxins" such as ethanol and tricyclic antidepressants) continue to be reported. This publication investigates factors that may explain these findings. Our results suggest that: 1) the relatively high absolute number of ECTR performed for non-classic toxins may simply reflect the large number of exposures to these toxins, 2) poisoning from another toxin may have been the reason for ECTR initiation in some exposures to non-classic toxins, 3) poisoning from non-classic toxins may receive ECTR for purposes other than toxin removal, and 4) the decisional threshold to initiate ECTR may be lower for non-classic toxins because of heightened toxicity.