Ajay Patial1, Rajdeep Kaur1, Arushi Gahlot Saini2, Seema Kapoor3, Sheetal Sharda4, Praveen Kumar5, Sunit Singhi6, Pratibha Singhi6, Isha Dwivedi1, Vivek Singh Malik1, Mini Tageja1, Gunjan Didwal1, Gursimran Kaur1, Bijo Varughese3, Savita Verma Attri7. 1. Pediatric Biochemistry Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India. 2. Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India. 3. Division of Genetics, Genetic & Metabolic Lab, Lok Nayak Hospital & Maulana Azad Medical College, New Delhi, India. 4. MedGenome Laboratories, Bangalore, Karnataka, India. 5. Department of Pediatrics, Neonatal Unit, Post Graduate Institute of Medical Education and Research, Chandigarh, India. 6. Pediatric Neurology and Neurodevelopment, Medanta, The Medicity, Haryana, Gurgaon, India. 7. Pediatric Biochemistry Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India. attrisavi@yahoo.co.in.
Abstract
OBJECTIVES: To determine the incidence and types of inborn errors of metabolism (IEMs) in high-risk children using mass spectrometry techniques. METHODS: Children considered high-risk for IEM were screened for metabolic diseases during a 3-y period. Dried blood spots and urine samples were analyzed by tandem mass spectrometry (LC-MS/MS) and gas chromatograph-mass spectrometry (GCMS). Samples with abnormal amino acids were confirmed by high-performance liquid chromatography (HPLC). RESULTS: Eight hundred and twenty-two suspected cases were evaluated; of which, 87 possible cases of IEMs were identified. Homocystinuria (n = 51) was the most common IEM detected followed by biotinidase deficiency (n = 7), glutaric aciduria type 1 (n = 7), and carnitine uptake defect (n = 6). Overall, there were 45 (51.7%) cases of organic acidemia, 31 cases (35.6%) of amino acid defect, 9 (10.3%) cases of fatty-acid oxidation disorders, and 2 (2.3%) cases of probable mitochondrial disorder. CONCLUSION: IEMs are common in India, with a hospital-based incidence of 1 in approximately 6642 among high-risk children. Screening of high-risk children by mass spectrometry techniques is a valuable strategy for early diagnosis of IEMs where universal newborn screening is not yet available.
OBJECTIVES: To determine the incidence and types of inborn errors of metabolism (IEMs) in high-risk children using mass spectrometry techniques. METHODS: Children considered high-risk for IEM were screened for metabolic diseases during a 3-y period. Dried blood spots and urine samples were analyzed by tandem mass spectrometry (LC-MS/MS) and gas chromatograph-mass spectrometry (GCMS). Samples with abnormal amino acids were confirmed by high-performance liquid chromatography (HPLC). RESULTS: Eight hundred and twenty-two suspected cases were evaluated; of which, 87 possible cases of IEMs were identified. Homocystinuria (n = 51) was the most common IEM detected followed by biotinidase deficiency (n = 7), glutaric aciduria type 1 (n = 7), and carnitine uptake defect (n = 6). Overall, there were 45 (51.7%) cases of organic acidemia, 31 cases (35.6%) of amino acid defect, 9 (10.3%) cases of fatty-acid oxidation disorders, and 2 (2.3%) cases of probable mitochondrial disorder. CONCLUSION: IEMs are common in India, with a hospital-based incidence of 1 in approximately 6642 among high-risk children. Screening of high-risk children by mass spectrometry techniques is a valuable strategy for early diagnosis of IEMs where universal newborn screening is not yet available.