Int J Neurosci, 2013; Early Online: 1–5 Copyright C  2013 Informa Healthcare USA, Inc. ISSN: 0020-7454 print / ISSN: 1543-5245 online DOI: 10.3109/00207454.2013.782026 Original Article North America and South America (NA-SA) neuropathy project Mamatha Pasnoor, 1 Osvaldo J. M. Nascimento, 2 Jaya Trivedi, 3 Gil I. Wolfe, 4 Sharon Nations, 3 Laura Herbelin, 1 M. G. de Freitas, 2 Giseli Quintanilha, 2 Saud Khan, 5 Mazen Dimachkie, 1 and Richard Barohn 1 1 Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA, 2 Department of Neurology, Federal Fluminense University, Rio de Janeiro, Brazil, 3 Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX, USA, 4 Neurology/Jacobs Neurological Institute, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA, and 5 John Peter Smith Hospital, Fort Worth, TX, USA Peripheral neuropathy is a common neurological disorder. There may be important differences and similarities in the diagnosis of peripheral neuropathy between North America (NA) and South America (SA). Neuromuscular databases were searched for neuropathy diagnosis at two North American sites, University of Kansas Medical Center and University of Texas Southwestern Medical Center, and one South American site, Federal Fluminense University in Brazil. All patients were included into one of the six major categories: immune-mediated, diabetic, hereditary, infectious/inlammatory, systemic/metabolic/toxic (not diabetic) and cryptogenic. A comparison of the number of patients in each category was made between North America and South America databases. To- tal number of cases in North America was 1090 and in South America was 1034 [immune-mediated: NA 215 (19.7%), SA 191 (18%); diabetic: NA 148 (13.5%), SA 236 (23%); hereditary: NA 292 (26.7%), SA 103 (10%); infectious/inlammatory: NA 53 (4.8%), SA 141 (14%); systemic/metabolic/toxic: NA 71 (6.5%), SA 124 (12%); cryptogenic: NA 311 (28.5%), SA 239 (23%)]. Some speciic neuropathy comparisons were hereditary neu- ropathies [Charcot–Marie–Tooth (CMT) cases] in NA 246/292 (84.2%) and SA 60/103 (58%); familial amyloid neuropathy in SA 31/103 (30%) and none in NA. Among infectious neuropathies, cases of human T-lymphotropic virus type 1 (HTLV-1) neuropathy in SA were 36/141(25%), Chagas disease in SA were 13/141(9%) and none for either in NA; cases of neuropathy due to leprosy in NA were 26/53 (49%) and in SA were 39/141(28%). South American tertiary care centers are more likely to see patients with infectious, diabetic and hereditary disorders such as familial amyloid neuropathies. North American tertiary centers are more likely to see patients with CMT. Immune neuropathies and cryptogenic neuropathies were seen equally in North America and South America. KEYWORDS: peripheral neuropathy, cryptogenic sensory polyneuropathy, neuropathy database Introduction Peripheral neuropathy (PN) is a common neurologi- cal disorder confronting neurologists [1]. Twenty mil- lion people are affected with neuropathy in the United States. About 70% of these can be classiied based on the etiology with diabetic neuropathy being the most common and approximately 30% of the peripheral neuropathies remain unclassiied [2–4]. A Mayo clinic evaluation of 205 cases of neuropathy revealed 42% inherited disorders, 21% inlammatory demyelinating Received 26 November 2012; revised 28 February 2013; accepted 28 February 2013. Correspondence: Mamatha Pasnoor, MD, Department of Neurology, University of Kansas Medical Center, 3901 Rainbow Blvd/ MSN 2012, Kansas City, KS 66160, USA. Tel: 913-588-6970. E-mail: mpasnoor@kumc.edu polyradiculopathy, 13% other acquired neuropathies and 24% remained undiagnosed [5]. Another study by Wolfe et al. analyzed 402 patients with peripheral neu- ropathy in two university-based neuromuscular clinics. Twenty-three percent of patients had cryptogenic or id- iopathic neuropathy [6]. Diabetes is the leading cause of neuropathy in the developed countries of the world. It affects approximately 50% of the people with diabetes [7,8]. Charcot–Marie–Tooth (CMT) is the most com- mon inherited neurological disorder, affecting approxi- mately 150 000 Americans. Estimates of the frequency of each CMT subtype in the United States are variable [9]. Infectious neuropathy affects a large number of peo- ple worldwide, mainly in the developing countries [10]. We hypothesize that there may be important dif- ferences and similarities in the diagnosis of peripheral 1 Int J Neurosci Downloaded from informahealthcare.com by Dr. Kelly Lyons on 05/07/13 For personal use only.