1 HYPEREXCRETION OF HOMOCITRULLINE IN A MALAYSIAN PATIENT WITH LYSINURIC 2 PROTEIN INTOLERANCE 3 4 Anasufiza Habib 1, Zabedah Md Yunus 1, Nor Azimah Azize 2, Gaik-Siew Ch’ng 3, Winnie PeiTee Ong 3, Bee-Chin 5 Chen 3, Ho-Torng Hsu 4, Ke-Juin Wong 4, James Pitt 5, Lock-Hock Ngu 3 6 7 1Biochemistry Unit, Specialised Diagnostic Centre, Institute for Medical Research, Kuala Lumpur, Malaysia. 8 2Molecular Diagnostics and Protein Unit, Institute for Medical Research, Kuala Lumpur, Malaysia. 9 3Department of Genetics and Metabolic, Kuala Lumpur Hospital, Malaysia 10 4Department of Paediatrics, Duchess of Kent Hospital, Sandakan, Sabah, Malaysia 11 5VCGS Pathology, Murdoch Children’s Research Institute, Royal Children's Hospital, Melbourne Australia 12 13 14 15 Author responsible for correspondence and proof: 16 Anasufiza Habib, 17 Biochemistry Unit, Specialised Diagnostic Centre, 18 Institute for Medical Research, 19 Jalan Pahang 50588 Kuala Lumpur 20 Malaysia 21 Email:
[email protected] 22 Telephone: +0603-26162627 23 Fax: +0603-26938210 24 25 26 27 28 1 29 ABSTRACT 30 Lysinuric Protein Intolerance (LPI, MIM 222700) is an inherited aminoaciduria with an autosomal recessive mode 31 of inheritance. Biochemically, affected patients present with increased excretion of the cationic amino acids; lysine, 32 arginine and ornithine. We report the first case of LPI diagnosed in Malaysia presented with excessive excretion of 33 homocitrulline. The patient was a 4 years old male who presented with delayed milestones, recurrent diarrhea and 34 severe failure to thrive. He developed hyperammonemic coma following a forced protein-rich diet. Plasma amino 35 acids analysis showed increased glutamine, alanine and citrulline; but decreased lysine, arginine and ornithine.