Zhang, M.

Background: Levetiracetam administration via intravenous push (IVP) may improve outcomes in status epilepticus (SE) by decreasing time to administration. However, there is a paucity of literature describing the safety of IVP administration of higher loading doses used for early management of SE. Objective: The purpose of this evaluation was to investigate the safety of high-dose IVP levetiracetam. Methods: This was a retrospective, single-arm cohort study conducted at an academic medical center. Patients were included if they received IVP levetiracetam ≥3000 mg. The primary outcome was a composite of clinically significant adverse events (AEs) within 1-hour post-administration of levetiracetam: hypotension, hypertension, bradycardia, tachycardia, arrhythmia, and/or injection site reaction. Results: A total of 140 patients met inclusion criteria, receiving a median levetiracetam dose of 4000 mg (interquartile range [IQR] = 3000, 4500). Seventeen (12.1%) patients experienced a clinically significant AE. The most common clinically significant AE was hypotension (9.2% [10/109]), followed by tachycardia (3.6% [4/112]), arrhythmia (1.8% [2/112]), hypertension (0.9% [1/109]), and injection site reaction (0.7% [1/140]). Eighty percent [8/10] of patients who experienced clinically significant hypotension were on at least 1 medication with potential confounding hemodynamic effects. Conclusion and Relevance: In this retrospective, single-arm analysis, high-dose (≥3000 mg) IVP levetiracetam was relatively well-tolerated but associated with a higher rate of clinically significant hypotension than has been reported in the previous literature, although several confounding factors may have contributed to this outcome. Our findings support the continued use of high-dose IVP levetiracetam with appropriate hemodynamic monitoring; hemodynamic effects should be further explored in future studies.

ABSTRACT Campylobacter fetus is known to cause human disease, particularly in elderly and immunocompromised hosts. There are limited published data for antimicrobial susceptibility patterns with this organism, and no interpretive criteria are available. We reviewed antimicrobial susceptibilities of C. fetus isolates tested at a tertiary care center and reference laboratory over an 11-year period. C. fetus isolates from patients treated at Mayo Clinic and those sent as referrals for identification and susceptibility were included. Antimicrobial susceptibility testing was performed using agar dilution for ciprofloxacin, doxycycline, erythromycin, gentamicin, meropenem, and tetracycline. Geographic distribution, culture source, organism minimal inhibitory concentration (MIC) distributions, and MIC 50 and MIC 90 were examined. Excluding duplicates, 105 unique isolates were identified from 110 positive cultures. Blood cultures represented the most common source, followed by body fluids, skin and soft tissue, and central nervous system. Gentamicin and meropenem had favorable MIC 50 and MIC 90 of 1 µg/mL. Ciprofloxacin demonstrated an MIC 50 of 1 µg/mL; however, the MIC 90 was >2 µg/mL. Erythromycin demonstrated MIC 50 and MIC 90 of 2 µg/mL. Tetracycline and doxycycline were tested on a limited number of isolates and showed a wide range of MICs. Gentamicin and meropenem demonstrated favorable MICs in C. fetus isolates. These may represent therapeutic options for consideration in serious C. fetus infections, pending susceptibility results. Ciprofloxacin, which showed variable results, may be more appropriate for use only after susceptibility testing. C. fetus interpretive criteria are needed to aid clinicians in selection of both empiric and definitive therapies. IMPORTANCE Our findings contribute to the scant literature on Campylobacter fetus antimicrobial susceptibility test results. We used a reference test method of agar dilution and provide MICs for a large number of organisms and antimicrobial agents.

The decrease in cancellous bone formation after estrogen treatment is generally thought to be coupled with a prior decrease in bone resorption. To test the possibility that estrogen has rapid tissue-specific actions on bone metabolism, we determined the time course (1–32 h) effects of diethylstilbestrol on steady-state mRNA levels for immediate-response genes, extracellular matrix proteins, and signaling peptides in the proximal tibial metaphysis and uterus by using Northern blot and RNase protection assays. The regulation of signaling peptides by estrogen, although tissue specific, followed a similar time course in bone and uterus. The observed rapid decreases in expression of insulin-like growth factor I, a growth factor associated with bone formation; decreases in mRNA levels for bone matrix proteins; evidence for reduced bone matrix synthesis; failure to detect rapid increases in mRNA levels for signaling peptides implicated in mediating the inhibitory effects of estrogen on bone resorption (interleukin-1 and -6) as well as other cytokines that can increase bone resorption; and the comparatively long duration of the bone remodeling cycle in rats indicate that estrogen can decrease bone formation by a mechanism that does not require a prior reduction in bone resorption.