title: Semilobar holoprosencephaly in a 12-month-old baby boy born to a primigravida patient with type 1 diabetes mellitus: a case report.
abstract: BACKGROUND
  Holoprosencephaly is a rare spectrum of cephalic disorders resulting from a failure or incomplete division of the embryonic forebrain into distinct cerebral hemispheres. It is the most common brain malformation with an incidence of 1:250 during embryogenesis; however, owing to the associated high rates of spontaneous abortion the incidence is 1:16,000 among live deliveries. Pathogenesis of holoprosencephaly is complex and heterogeneous involving genetic abnormalities, teratogenic exposures, and syndromic associations. Among the teratogenic exposures, maternal diabetes is a well-established risk factor associated with a 200-fold increased incidence of holoprosencephaly.
  
  
  METHODS
  We report a case of a delayed diagnosis of semilobar holoprosencephaly in a 12-month-old baby boy of African descent who presented to us with a history of global developmental delay, erratic sleep patterns, and poor weight gain. He was born to a type 1 diabetes mellitus mother at 39+ weeks by emergency cesarean section due to fetal distress and breech presentation. The baby weighed 2315 g and had Apgar scores of 6/10 and 8/10 at 1 and 5 minutes respectively. A physical examination done at 12 months of age revealed a small-for-age child with a developmental age of 2 months. He had normal facies but a neurological examination revealed hypotonia in all four limbs. The rest of systemic examination was unremarkable. Hematological and biochemical investigations revealed normal findings except for iron deficiency anemia. The child also underwent magnetic resonance imaging of his brain which revealed distinctive features of semilobar holoprosencephaly. He was treated for iron deficiency anemia with Hemovit syrup (ferric ammonium citrate, folic acid, pyridoxine hydrochloride, cyanocobalamin, and zinc sulfate) 10 ml thrice daily, ferrous sulfate 10 mg once daily, folic acid 1 mg once daily, and multivitamin syrup 5 ml once daily. Furthermore, nutritional and genetic counseling was offered to his parents.
  
  
  CONCLUSIONS
  In conclusion, although rare, holoprosencephaly is the commonest structural anomaly of the brain with a complex and multifactorial etiopathogenesis. It is prudent to diagnose it prenatally, classify its severity, and forge its prognosis so that parents are counseled early enough to make informed decisions especially where termination of pregnancy may be implicated.
authors.affiliation: Unit of Research, Department of Cardiovascular Medicine, The Jakaya Kikwete Cardiac Institute, PO Box 65141, Dar es Salaam, Tanzania. pedro.pallangyo@gmail.com.
authors.forename: Pedro
authors.initials: P
authors.lastname: Pallangyo
authors.affiliation: Department of Radiology, Muhimbili National Hospital, PO Box 65000, Dar es Salaam, Tanzania.
authors.forename: Frederick
authors.initials: F
authors.lastname: Lyimo
authors.affiliation: Unit of Research, Department of Cardiovascular Medicine, The Jakaya Kikwete Cardiac Institute, PO Box 65141, Dar es Salaam, Tanzania.
authors.forename: Paulina
authors.initials: P
authors.lastname: Nicholaus
authors.affiliation: Department of Radiology, Muhimbili National Hospital, PO Box 65000, Dar es Salaam, Tanzania.
authors.forename: Hilda
authors.initials: H
authors.lastname: Makungu
authors.affiliation: Department of Radiology, Muhimbili National Hospital, PO Box 65000, Dar es Salaam, Tanzania.
authors.forename: Maria
authors.initials: M
authors.lastname: Mtolera
authors.affiliation: Department of Pediatric Cardiology, Jakaya Kikwete Cardiac Institute, PO Box 65141, Dar es Salaam, Tanzania.
authors.forename: Isaac
authors.initials: I
authors.lastname: Mawenya
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000178:diet therapy*; D001921:Brain / Q000002:abnormalities* / Q000473:pathology; D002585:Cesarean Section; D002657:Child Development; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D005260:Female; D005817:Genetic Counseling; D016142:Holoprosencephaly / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D018673:Nutrition Policy; D011247:Pregnancy; D011254:Pregnancy in Diabetics / Q000503:physiopathology*
keywords: Case report; Developmental delay; Holoprosencephaly; Semilobar holoprosencephaly; Structural brain malformation