Ortega García et al. Journal of Medical Case Reports 2011, 5:129 http://www.jmedicalcasereports.com/content/5/1/129 C A S E R E P O R T JOURNAL OF MEDICAL CASE REPORTS Open Access Prenatal exposure of a girl with autism spectrum disorder to ‘horsetail’ (Equisetum arvense) herbal remedy and alcohol: a case report Juan A Ortega García1*, Mario G Angulo1, Elías J Sobrino-Najul1, Offie P Soldin2, Alberto Puche Mira3, Eduardo Martínez-Salcedo3 and Luz Claudio4 Abstract Introduction: Autism is a complex neurodevelopmental disorder in which the interactions of genetic, epigenetic and environmental influences are thought to play a causal role. In humans, throughout embryonic and fetal life, brain development is exquisitely susceptible to injury caused by exposure to toxic chemicals present in the environment. Although the use of herbal supplements during pregnancy is relatively common, little information is available on their association with fetal neurodevelopment. This is, to the best of our knowledge, the first report in the literature to associate a new plausible mechanism of neurodevelopmental toxicity with a case of autism spectrum disorder through a vitamin deficiency potentiated by concomitant use of herbal supplements and ethanol exposure. Case presentation: We describe the pediatric environmental history of a three-year-old Caucasian girl with an autism spectrum disorder. We utilized her pediatric environmental history to evaluate constitutional, genetic, and environmental factors pertinent to manifestation of neurodevelopment disorders. Both parents reported prenatal exposure to several risk factors of interest. A year prior to conception the mother began a weight loss diet and ingested 1200 mg/day of ‘horsetail’ (Equisetum arvense) herbal remedies containing thiaminase, an enzyme that with long-term use can lead to vitamin deficiency. The mother reported a significant weight loss during the pregnancy and a deficiency of B-complex vitamins. Thiamine (vitamin B1) deficiency could have been potentiated by the horsetail’s thiaminase activity and ethanol exposure during pregnancy. No other risk factors were identified. Conclusions: A detailed and careful pediatric environmental history, which includes daily intake, herbal remedies and ethanol exposure, should be obtained from all patients with autism spectrum disorder. Maternal consumption of ethanol and of herbal supplements with suspected or potential toxicity should be avoided during pregnancy. The prospective parents should perform preconception planning before pregnancy. Introduction Autism refers to a set of neurodevelopmental disorders characterized by impaired social interaction, restricted communication, and repetitive, stereotypic behaviors. The number of children reported as having autism spectrum disorders (ASDs) has risen dramatically since the early 1990s. The prevalence of autism currently reported in developed countries is 3 to 7 cases per 1000 * Correspondence: ortega@pehsu.org 1Pediatric Environmental Health Specialty Unit, Neuropediatric Unit, Department of Pediatrics, University Hospital Virgen of Arrixaca, Murcia, Spain Full list of author information is available at the end of the article children [1-3]. Genetic predisposition could explain approximately 7% to 8% of all cases and that percentage is expected to increase with progress in autism research. Monozygotic twin concordance is found to be around 70% and 90% for autistic behavioral traits only. How- ever, in dizygotic twins, it does not appear to be higher than in isolated brothers. Some genetic diseases such as fragile X syndrome, Down’s syndrome, Angelman syn- drome, Rett syndrome and Cohen syndrome signifi- cantly increase the risk of developing autism [4]. Despite the advances in autism research, certain clini- cal and epidemiological aspects of autism remain largely unknown. For example, the sporadic appearance and © 2011 Ortega García et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.