title: Cobalamin F disease detected by newborn screening and follow-up on a 14-year-old patient.
abstract: The cobalamin F (cblF) defect is caused by disturbed lysosomal release of cobalamin (vitamin B(12)) into the cytoplasm caused by mutations in the LMBRD1 gene. We present the clinical and biochemical characterization of a patient with newly diagnosed cblF disease and a follow-up on a 14-year-old patient. The new patient presented with elevation of propionyl carnitine found on a newborn screen. The patient was small for gestational age, exhibited dysmorphic features and mild developmental delay, and had trigonocephaly and ventricular septal defect. There was biochemical normalization and clinical improvement within 3 weeks of parenteral cobalamin treatment. The other patient presented at 4 weeks of life with failure to thrive and feeding difficulties. She was treated only with monthly cyanocobalamin shots. The patient has never experienced metabolic decompensation. She had short stature and was an average student with no behavioral concerns. Her metabolic derangements normalized after switching to weekly hydroxycobalamin. The available data on 14 patients with confirmed cblF disease suggest variability in age of onset, presenting symptoms, response to treatment, and long-term complications. Common clinical findings include small for gestational age, feeding difficulties, growth failure, and developmental delays. Some patients have congenital heart defects, dysmorphic features, and other congenital anomalies.
authors: Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA.
authors: Olajumoke
authors: O
authors: Oladipo
authors: David S
authors: DS
authors: Rosenblatt
authors: David
authors: D
authors: Watkins
authors: Isabelle Racine
authors: IR
authors: Miousse
authors: Laurie
authors: L
authors: Sprietsma
authors: Dennis J
authors: DJ
authors: Dietzen
authors: Marwan
authors: M
authors: Shinawi
mesh_terms: D000293:Adolescent; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D009154:Mutation; D029543:Nucleocytoplasmic Transport Proteins / Q000235:genetics*; D010641:Phenotype; D014806:Vitamin B 12 Deficiency / Q000235:genetics*
chemical_list: C502888:LMBRD1 protein, human; D029543:Nucleocytoplasmic Transport Proteins