Fetal and Pediatric Pathology, 29:69–80, 2010 Copyright C  Informa Healthcare USA, Inc. ISSN: 1551-3815 print / 1551-3823 online DOI: 10.3109/15513811003615005 ANENCEPHALY-EXENCEPHALY SEQUENCE AND CONGENITAL DIAPHRAGMATIC HERNIA IN A FETUS WITH 46,XX KARYOTYPE: Early Prenatal Diagnosis, Necropsy, and Maternal Folate Pathway Genetic Analysis Gabriele Tonni, Daniela Azzoni, and Cristina Pizzi ✷ Division of Obstetrics and Gynecology, Guastalla Provincial Hospital, AUSL Reggio Emilia, Italy Maria Paola Bonasoni ✷ Pathology Service, Arcispedale “Santa Maria Nuova”, Reggio Emilia, Italy Pietro Cavalli ✷ Director, Genetic Service “Istituti Ospitalieri,” Cremona, Italy Pierpaolo Pattacini ✷ Director, Radiology Service, Guastalla Provincial Hospital, AUSL Reggio Emilia, Italy Alessandro Ventura ✷ Director, Division of Obstetrics and Gynecology, Guastalla Provincial Hospital, AUSL Reggio Emilia, Italy Keywords neural tube defects, diaphragmatic hernia, prenatal diagnoses, karyotype, ultrasound, magnetic resonance imaging, necropsy INTRODUCTION Neural tube defects (NTDs) are a group of serious birth defects that affect the developing nervous system and include acrania, anencephaly, and encephalocele. Acrania may manifest as a partial or complete absence of the cranial vault and of cerebral hemispheres (forebrain) with abnormal brain development. Anencephaly instead is generally defined as the congenital absence of skull, scalp, and forebrain. Acrania occurs more infrequently than anencephaly and may be diagnosed prenatally during the first trimester [1, 2]. It may occur as a single, isolated malformation or with co-existing anomalies including extracranial defects such as rachischisis, hypoplastic ears, cleft lip and palate, omphalocele, limb defects, cardiac and kidney The authors are thank to Helen Diamond for careful revision of the manuscript. Address correspondence to Gabriele Tonni, MD, PhD, Prenatal Diagnostic Unit, Division of Ob- sterics & Gynecology, Guastalla Provincial Hospital AUSL Reggio Emilia, Via Donatori Sangue 2, 42016 Guastalla, Reggio Emilia, Italy. E-mail: Tonni.Gabriele@ausl.re.it 69