Peripheral neuropathy is common with many different etiologies. This is the first of three articles reviewing the less common causes of peripheral neuropathy. The first article includes the extrinsic causes of neuropathy including toxic/medications, infectious, nutritional, and systemic metabolic derangements. The second and third articles review the intrinsic causes of peripheral neuropathy. These reviews describe common presentations and constellation of manifestations and clinical findings.

Peripheral neuropathy is common and has many different etiologies. This is the last of three articles that review the less-common causes of peripheral neuropathy. Part III reviews the genetically coded causes of peripheral neuropathy, including those related to amyloidosis, neoplasm, paraproteinemias, as well as autosomal dominant, autosomal recessive, and x-linked causes. The extrinsic causes of neuropathy and the reactive or induced causes of neuropathy are covered in separate articles, Part I and Part II, respectively. The brief series reviews unusual causes of neuropathy and describes common presentations and the constellation of clinical findings. The goal is to help the clinician increase the diagnostic yield when sorting out the unusual causes of peripheral neuropathy.

Peripheral neuropathy is common with many different etiologies. This is the second of three articles to review the less-common causes of peripheral neuropathy. Part II reviews the intrinsic ''reactive'' causes of peripheral neuropathy, including those related to connective tissue, vasculitis, sarcoid, organ failure, and inflammatory bowel disease. The extrinsic causes of neuropathy and the induced or inherited causes of neuropathy are covered in separate articles in this issue of Seminars in Neurology, Part I and Part III, respectively. The brief series of reviews of causes of neuropathy describe common presentations and constellation of clinical findings. The goal is to help the practicing clinician increase the diagnostic yield when sorting out the unusual causes of peripheral neuropathy.

Background IV tPA utilization in acute ischemic stroke (AIS) requires weight-based dosing and a standardized infusion rate. In our regional network, we have tried to minimize tPA dosing errors. We describe the frequency and types of tPA administration errors made in our comprehensive stroke center (CSC) and at community hospitals (CHs) prior to transfer. Methods Using our stroke quality database, we extracted clinical and pharmacy information on all patients who received IV tPA from 2010–11 at the CSC or CH prior to transfer. All records were analyzed for the presence of inclusion/exclusion criteria deviations or tPA errors in prescription, reconstitution, dispensing, or administration, and analyzed for association with outcomes. Results We identified 131 AIS cases treated with IV tPA: 51% female; mean age 68; 32% treated at CSC, 68% at CH (including 26% by telestroke) from 22 CHs. tPA prescription and administration errors were present in 64% of all patients (41% CSC, 75% CH, p<0.001), the most common being incorrect dosage for body weight (19% CSC, 55% CH, p<0.001). Of the 27 overdoses, there were 3 deaths due to systemic hemorrhage or ICH. Nonetheless, outcomes (parenchymal hematoma, mortality, mRS) did not differ between CSC and CH patients nor between those with and without errors. Conclusion Despite focus on minimization of tPA administration errors in AIS patients, such errors were very common in our regional stroke system. Although an association between tPA errors and stroke outcomes was not demonstrated, quality assurance mechanisms are still necessary to reduce potentially dangerous, avoidable errors.

The ABC/2 method of volume estimation on CT perfusion is a reliable and efficient approach to determine infarct and penumbra volumes. The 1-CBV/MTT × 100% formula produces a mismatch percentage assisting providers in communicating the proportion of salvageable brain and guides therapy in the setting of patients with unclear time of onset with potentially salvageable tissue who can undergo mechanical retrieval or intraarterial thrombolytics.