Prolonged-release fampridine in multiple sclerosis: clinical data and real-world experience. Report of an expert meeting

Prolonged-release (PR) fampridine is the only approved medication to improve walking in multiple sclerosis (MS), having been shown to produce a clinically meaningful improvement in walking ability in the subset of MS patients with Expanded Disability Status Scale 4-7. Recent responder subgroup analyses in the phase III ENHANCE study show a large effect size in terms of an increase of 20.58 points on the patient-reported 12-item MS Walking Scale in the 43% of patients classified as responders to PR-fampridine, corresponding to a standardized response mean of 1.68. Use of PR-fampridine in clinical practice varies across Europe, depending partly on whether it is reimbursed. A group of European MS experts met in June 2017 to discuss their experience with using PR-fampridine, including their views on the patient population for treatment, assessment of treatment response, re-testing and re-treatment, and stopping criteria. This article summarizes the experts' opinions on how PR-fampridine can be used in real-world clinical practice to optimize the benefits to people with MS with impaired walking ability.

Treatment of methylmalonic acidemia by liver or combined liver-kidney transplantation

OBJECTIVE

To assess biochemical, surgical, and long-term outcomes of liver (LT) or liver-kidney transplantation (LKT) for severe, early-onset methylmalonic acidemia/acid (MMA).

STUDY DESIGN

A retrospective chart review (December 1997 to May 2012) of patients with MMA who underwent LT or LKT at Lucile Packard Children's Hospital at Stanford.

RESULTS

Fourteen patients underwent LT (n = 6) or LKT (n = 8) at mean age 8.2 years (range 0.8-20.7). Eleven (79%) were diagnosed during the neonatal period, including 6 by newborn screening. All underwent deceased donor transplantation; 12 (86%) received a whole liver graft. Postoperative survival was 100%. At a mean follow-up of 3.25 ± 4.2 years, patient survival was 100%, liver allograft survival 93%, and kidney allograft survival 100%. One patient underwent liver re-transplantation because of hepatic artery thrombosis. After transplantation, there were no episodes of hyperammonemia, acidosis, or metabolic decompensation. The mean serum MMA at the time of transplantation was 1648 ± 1492 μmol/L (normal <0.3, range 99-4420). By 3 days, post-transplantation levels fell on average by 87% (mean 210 ± 154 μmol/L), and at 4 months, they were 83% below pre-transplantation levels (mean 305 ± 108 μmol/L). Developmental delay was present in 12 patients (86%) before transplantation. All patients maintained neurodevelopmental abilities or exhibited improvements in motor skills, learning abilities, and social functioning.

CONCLUSIONS

LT or LKT for MMA eradicates episodes of hyperammonemia, results in excellent long-term survival, and suggests stabilization of neurocognitive development. Long-term follow-up is underway to evaluate whether patients who undergo early LT need kidney transplantation later in life.

Knowledge, understanding, and uptake of noninvasive prenatal testing among Latina women

OBJECTIVE

The aim of this study is to assess Latina patient understanding of noninvasive prenatal testing (NIPT) and identify what factors influence uptake/refusal to NIPT to adapt counseling to the needs and interests of this population.

METHODS

Mixed-methods survey in English and Spanish administered to pregnant Latina patients throughout pregnancy.

RESULTS

Sixty-three women participated in our study (67% response rate); 34.9% chose to do NIPT, and 65.1% declined. Approximately half of participants (44%) had an NIPT knowledge score of ≤3 out of six total questions. Two of the most significant factors influencing uptake of NIPT were a higher reported educational level (p = 0.015) and a higher NIPT knowledge score (p = 0.014); 42.9% of participants knew that NIPT only screens for certain chromosomal conditions; 39% of women who declined NIPT would never consider NIPT in the future.

CONCLUSIONS

One-third of Latina women elected NIPT; a higher reported educational level and language were most predictive of this choice. Overall knowledge was significantly lower for women who declined NIPT. Lower knowledge may suggest that not all women are making informed decisions because of varying degrees of informed consent. Providing culturally tailored information can help women navigate the complexities of prenatal testing in order to make decisions most aligned with their values.

Use of outpatient parenteral antimicrobial therapy for transrectal ultrasound-guided prostate biopsy prophylaxis in the setting of community-associated multidrug-resistant Escherichia coli rectal colonization

OBJECTIVE

To study the use of ertapenem delivered in an outpatient parenteral antimicrobial therapy (OPAT) hospital-based unit setting for targeted transrectal ultrasound-guided prostate biopsy (TRUSPBx) prophylaxis in the setting of multidrug-resistant (MDR) Escherichia coli rectal colonization. E coli is the pathogen most commonly associated with post-TRUSPBx complications, and there is increasing prevalence of community-associated MDR E coli.

METHODS

Prospective data analysis of all patients admitted to the OPAT unit for administration of intravenous antibiotics for prophylaxis for TRUSPBx over 18-month period was performed. Patients had identification of MDR E coli in rectal swab cultures and/or intolerance to available oral agents. Microbiologic data and tolerability of administered antibiotics and outcome after TRUSPBx were tabulated.

RESULTS

Nine patients (median age 74 years) were referred because of antibiotic-resistant E coli from rectal swabs (all fluoroquinolone resistant, 7 MDR). All patients received ertapenem 1 g intravenously 1 day before TRUSPBx and the day of the procedure before TRUSPBx. None of the patients experienced infectious complications immediately after TRUSPBx or several weeks or months later, and no patient was lost to urologic follow-up.

CONCLUSION

Increasing worldwide reports of prostatitis, urinary tract infections, and septicemia after TRUSPBx because of MDR E coli suggest rectal screening before procedure may be useful in decreasing complications. Targeted prophylaxis in these instances is necessary. Although carbapenems are used for treatment, they are not routinely used for prophylaxis. We report successful use of ertapenem delivered in a hospital-based OPAT unit for TRUSPBx prophylaxis.

Betabox: a beta particle imaging system based on a position sensitive avalanche photodiode

A beta camera has been developed that allows planar imaging of the spatial and temporal distribution of beta particles using a 14 × 14 mm(2) position sensitive avalanche photodiode (PSAPD). This camera system, which we call Betabox, can be directly coupled to microfluidic chips designed for cell incubation or other biological applications. Betabox allows for imaging the cellular uptake of molecular imaging probes labeled with charged particle emitters such as (18)F inside these chips. In this work, we investigate the quantitative imaging capabilities of Betabox for (18)F beta particles, in terms of background rate, efficiency, spatial resolution, and count rate. Measurements of background and spatial resolution are considered both at room temperature (21 °C ± 1 °C) and at an elevated operating temperature (37 °C ± 1 °C), as is often required for biological assays. The background rate measured with a 4 keV energy cutoff is below 2 cph mm(-2) at both 21 and 37 °C. The absolute efficiency of Betabox for the detection of (18)F positron sources in contact with a PSAPD with the surface passivated from ambient light and damage is 46% ± 1%. The lower detection limit is estimated using the Rose Criterion to be 0.2 cps mm(-2) for 1 min acquisitions and a 62 × 62 µm(2) pixel size. The upper detection limit is approximately 21 000 cps. The spatial resolution at both 21 and 37 °C ranges from 0.4 mm FWHM at the center of the field of view (FOV), and degrades to 1 mm at a distance of 5 mm away from center yielding a useful FOV of approximately 10 × 10 mm(2). We also investigate the effects on spatial resolution and sensitivity that result from the use of a polymer based microfluidic chip. For these studies we place varying layers of low-density polyethylene (LDPE) between the detector and the source and find that the spatial resolution degrades by ∼180 µm for every 100 µm of LDPE film. Sensitivity is reduced by half with the inclusion of ∼200 µm of additional LDPE film. Lastly, we demonstrate the practical utilization of Betabox, with an imaging test of its linearity, when coupled to a polydimethylsiloxane microfluidic chip designed for cell based assays.

Neutralizing antibodies are associated with a reduction of interferon-β efficacy during the treatment of Japanese multiple sclerosis patients

Multiple sclerosis (MS) is a chronic immune-mediated inflammatory demyelinating disease of the central nervous system. Interferon-β (IFN-β) has been used as the first line therapy for MS treatment in Japan, but patients treated with IFN-β may develop antibodies, known as neutralizing antibodies (NAbs), which abrogate its therapeutic effects. Intramuscular IFN-β 1a and subcutaneous IFN-β 1b are currently available in Japan, but large-scale studies evaluating the prevalence and clinical implications of NAbs against these IFN-β preparations in MS patients have only been performed in Caucasian populations. NAbs positivity has been reported to be associated with HLA-DRB1 alleles, suggesting that the positivity might differ among populations with distinct genetic backgrounds. Clinical information and sera were collected from 229 consecutive MS patients treated with IFN-β in 4 centers in Japan. Sera were tested for NAbs using a luciferase reporter gene assay. In total, 5.2% of IFN-β-1a-treated patients (4/77) and 30.3% of IFN-β-1b-treated patients (46/152) were positive for Nabs. The frequency of NAbs was highest in patients treated for 13 to 24 months. Clinical relapse and contrast-enhancing lesions in the magnetic resonance imaging increased together with NAbs titers in this group. In conclusion, the prevalence of NAbs in Japanese MS patients is similar to that in Caucasian populations and is associated with an increase in disease activity. Therefore, routine NAbs testing is recommended also in Asian populations to ensure the early identification of patients who would benefit from a change in therapy.

Safety trial of Floseal(®) haemostatic agent in head and neck surgery

INTRODUCTION

Floseal® (Baxter, Hayward, CA, US) can be of value in reducing blood loss and haematoma rates. The manufacturer’s warnings include allergic reaction, poor wound healing and intravascular thrombosis. We aimed to determine whether Floseal® is safe to use in various head and neck surgery (HNS) procedures.

METHODS

A prospective trial was conducted using Floseal® in 42 various consecutive head and neck surgery procedures. Adverse incidents were used as the main outcome measure, including allergic reaction, wound breakdown, wound infection and thrombosis. Secondary outcome measures included haematoma formation, hospital stay, drain times and output.

RESULTS

No adverse incidents were recorded in the trial period. Two patients developed haematomas and required surgical exploration where a bleeding vessel was identified and dealt with.

CONCLUSIONS

Floseal® is safe to be used in head and neck surgery with no adverse effects. A larger number and a control group are required to ascertain its value in reducing blood loss, haematoma formation, drain usage and hospital stay.