Muscle Relaxant Use Among Hemodialysis Patients: Prevalence, Clinical Indications, and Adverse Outcomes.

RATIONALE & OBJECTIVE: Muscle relaxants are often used to treat musculoskeletal pain or cramping, which are commonly experienced by hemodialysis patients. However, the extent to which muscle relaxants are prescribed in this population and the risks associated with their use have not been characterized. STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: 140,899 Medicare-covered adults receiving hemodialysis in 2011, identified in the US Renal Data System. EXPOSURE: Time-varying muscle relaxant exposure. OUTCOMES: Primary outcomes were time to first emergency department visit or hospitalization for altered mental status, fall, or fracture. Secondary outcomes were death and composites of death with each of the primary outcomes. ANALYTICAL APPROACH: Multivariable Cox regression analysis. RESULTS: 10% of patients received muscle relaxants in 2011. 11%, 6%, 3%, and 13% had an episode of altered mental status, fall, fracture, and death, respectively. Muscle relaxant use was associated with higher risk for altered mental status (HR, 1.39; 95% CI, 1.29-1.51) and fall (HR, 1.18; 95% CI, 1.05-1.33) compared to no use. Muscle relaxant use was not statistically significantly associated with higher risk for fracture (HR, 1.17; 95% CI, 0.98-1.39). Muscle relaxant use was associated with lower hazard of death (HR, 0.85; 95% CI, 0.76-0.94). However, hazards were higher for altered mental status or death (HR, 1.17; 95% CI, 1.10-1.25), fall or death (HR, 1.14; 95% CI, 1.06-1.22), and fracture or death (HR, 1.10; 95% CI, 1.01-1.20). LIMITATIONS: A causal association between muscle relaxant use and outcomes cannot be inferred, and residual confounding cannot be excluded. Exposure and outcomes were ascertained using administrative claims. CONCLUSIONS: Muscle relaxant use was common in hemodialysis patients and associated with altered mental status and falls. We could not rule out a clinically meaningful association between muscle relaxant use and fracture. The lower risk for death with muscle relaxants may have been the result of residual confounding. Future research to define the appropriate use of muscle relaxants in this population is warranted.

Subclinical metabolic and cardiovascular abnormalities in autosomal dominant polycystic kidney disease
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Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent genetic kidney disease. It carries high lifetime morbidity not only due to chronic kidney disease, but also due to a higher risk of cardiovascular death. Multiple metabolic abnormalities associated with ADPKD including insulin resistance and hyperlipidemia as well as subclinical cardiovascular abnormalities, such as left ventricular hypertrophy (LVH), contribute to this cardiovascular risk. These conditions may manifest before evidence of worsening estimated glomerular filtration rate (eGFR). Renal oxidative stress also occurs early in the disease and is a driver of ADPKD progression. Animal models have shown that calorie restriction may mitigate these inflammatory processes. Further research is required to show whether attenuation of metabolic abnormalities associated with ADPKD may improve renal and cardiovascular morbidity.
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Proper name anomia in poststroke aphasics: evidence from a multiple-case study.

We aimed to characterize difficulties in famous face naming in three poststroke aphasic patients with a lesion limited to the left mid-posterior temporal language regions, sparing the anterior temporal lobe. The patients did not present semantic deficits specific to known people. Nonetheless, they showed difficulties naming famous buildings in addition to famous faces, but they were comparable to healthy controls in generating proper names. Our results support the critical role of the mid-posterior temporal language regions in the lexical retrieval of proper names, namely from pictorial stimuli, in absence of semantic impairments.

Utilization of gene mapping and candidate gene mutation screening for diagnosing clinically equivocal conditions: a Norrie disease case study.

Prenatal diagnosis was requested for an undiagnosed eye disease showing X-linked inheritance in a family. No medical records existed for the affected family members. Mapping of the X chromosome and candidate gene mutation screening identified a c.C267A[p.F89L] mutation in NPD previously described as possibly causing Norrie disease. The detection of the c.C267A[p.F89L] variant in another unrelated family confirms the pathogenic nature of the mutation for the Norrie disease phenotype. Gene mapping, haplotype analysis, and candidate gene screening have been previously utilized in research applications but were applied here in a diagnostic setting due to the scarcity of available clinical information. The clinical diagnosis and mutation identification were critical for providing proper genetic counseling and prenatal diagnosis for this family.

Antimicrobial susceptibility profiles of Salmonella enterica serotypes recovered from pens of commercial feedlot cattle using different types of composite samples.

Salmonella enterica in cattle production systems may be associated with important human and animal disease issues. However, tremendous diversity exists among Salmonella recovered, and more information is needed about strains of greatest potential health concern, particularly those that are multidrug resistant (MDR). By characterizing Salmonella isolates from commercial feedlot pens, this study aimed to evaluate the strain diversity and prevalence of MDR Salmonella from different types of composite pen samples. Antimicrobial susceptibility profiles, serotype, and presence or absence of the integron-encoded intI1 gene were determined for 530 Salmonella isolates recovered using composite rope (n = 335), feces (n = 59), and water (n = 136) samples from 21 pens in 3 feedlots. The study investigated only pens with available isolates from multiple sample types. Most isolates (83.0%) of the 19 Salmonella serotypes identified were susceptible or intermediately susceptible to all the antimicrobials evaluated. Resistance to sulfisoxazole (14.9%), streptomycin (3.8%), and tetracycline (3.6%) were the most common. None of the isolates tested positive for a class 1 integron, and only 2.5% were resistant to multiple antimicrobials. All the MDR isolates, namely, serotypes Uganda (n = 9), Typhimurium (n = 2), and Give (n = 2), were resistant to at least five antimicrobials. Most MDR isolates (n = 11) were from two pens during 1 week within one feedlot. Overall, many Salmonella isolates collected within a pen were similar in terms of serotype and antimicrobial susceptibility regardless of sample type. However, MDR Salmonella and rare serotypes were not recovered frequently enough to suggest a general strategy for appropriate composite sampling of feedlot cattle populations for Salmonella detection and monitoring.