A Quasi-Experiment To Study the Impact of Vancomycin Area under the Concentration-Time Curve-Guided Dosing on Vancomycin-Associated Nephrotoxicity.

Evidence suggests that maintenance of vancomycin trough concentrations at between 15 and 20 mg/liter, as currently recommended, is frequently unnecessary to achieve the daily area under the concentration-time curve (AUC24) target of ≥400 mg · h/liter. Many patients with trough concentrations in this range have AUC24 values in excess of the therapeutic threshold and within the exposure range associated with nephrotoxicity. On the basis of this, the Detroit Medical Center switched from trough concentration-guided dosing to AUC-guided dosing to minimize potentially unnecessary vancomycin exposure. The primary objective of this analysis was to assess the impact of this intervention on vancomycin-associated nephrotoxicity in a single-center, retrospective quasi-experiment of hospitalized adult patients receiving intravenous vancomycin from 2014 to 2015. The primary analysis compared the incidence of nephrotoxicity between patients monitored by assessment of the AUC24 and those monitored by assessment of the trough concentration. Multivariable logistic and Cox proportional hazards regression examined the independent association between the monitoring strategy and nephrotoxicity. Secondary analysis compared vancomycin exposures (total daily dose, AUC, and trough concentrations) between monitoring strategies. Overall, 1,280 patients were included in the analysis. After adjusting for severity of illness, comorbidity, duration of vancomycin therapy, and concomitant receipt of nephrotoxins, AUC-guided dosing was independently associated with lower nephrotoxicity by both logistic regression (odds ratio, 0.52; 95% confidence interval [CI], 0.34 to 0.80; P = 0.003) and Cox proportional hazards regression (hazard ratio, 0.53; 95% CI, 0.35 to 0.78; P = 0.002). AUC-guided dosing was associated with lower total daily vancomycin doses, AUC values, and trough concentrations. Vancomycin AUC-guided dosing was associated with reduced nephrotoxicity, which appeared to be a result of reduced vancomycin exposure.

Guillain-Barré syndrome in an older man following influenza vaccination.

OBJECTIVE To report an atypical case of Guillain-Barré syndrome (GBS) after administration of the 2012-13 influenza vaccine. SETTING Urban tertiary hospital. PATIENT DESCRIPTION An 81-year-old man was admitted to the hospital after he began experiencing numbness and tingling in both feet that began ascending toward the waistline. The patient complained of intense neuropathic pain in his lower extremities and eventually lost the deep tendon reflexes in his ankles. CASE SUMMARY In addition to clinical manifestations of GBS, electromyography revealed a sensorimotor, polyneuropathy, predominantly axonal, with prolonged F-waves in all nerves tested. A lumbar puncture revealed clear and colorless cerebrospinal fluid with an elevated protein level of 66 mg/dL (reference, 15-60 mg/dL) despite the lack of a normal cell count, which indicates albuminocytologic dissociation. Based on these findings, the patient met Brighton level 3 diagnostic certainty and was diagnosed with GBS. MAIN OUTCOMES MEASURE Signs and symptoms of GBS. RESULTS On day 5 of hospitalization, intravenous immunoglobulin 0.4 mg/kg/d was initiated for 5 days in combination with gabapentin 100 mg at bedtime for neuropathic pain. After completing treatment, the patient experienced progressively improved sensation in his extremities and was discharged. CONCLUSION This is a rare report of GBS lacking albuminocytologic dissociation after an older patient received the 2012-13 influenza vaccine.