Congenital methemoglobinaemia due to Hb F-M-Fort Ripley in a preterm newborn. (11th March 2016)

• Record Type: Journal Article
• Authors: Ghotra, Satvinder; Jangaard, Krista; Pambrun, Chantale; Fernandez, Conrad Vincent
• Is Part Of: BMJ case reports. Volume 2016
• Publication Date: 2016-03-11
• Subjects: Medicine -- Case studies -- Periodicals; 610.5
• DOI: 10.1136/bcr-2016-214381
• Languages: English
• ISSNs: 1757-790X

Abstract

Abstract : Methemoglobinaemia is a rare cause of cyanosis in newborns. Congenital methemoglobinaemias due to M haemoglobin or deficiency of cytochrome b5 reductase are even rarer. We present a case of congenital methemoglobinaemia presenting at birth in a preterm infant. A baby boy born at 29 weeks and 3 days of gestation had persistent central cyanosis immediately after delivery, not attributable to a respiratory or cardiac pathology. Laboratory methemoglobin levels were not diagnostic. Cytochrome b5 reductase levels were normal and a newborn screen was unable to pick up any abnormal variants of fetal haemoglobin. Genetic testing showed a γ globin gene mutation resulting in the M haemoglobin, called Hb F-M-Fort Ripley. The baby had no apparent cyanosis at a corrected gestational age of 42 weeks. Although rare, congenital methaemoglobin aemia should be considered in the differential in a preterm with central cyanosis and investigated with genetic testing for γ globin chain mutations if other laboratory tests are non-conclusive.