Publication

Abstract : DIAGNOSIS OF NEUROMETABOLIC DISORDRS IN CHILDREN BY SIMPLE SCREENING TESTS AND HPLC M.P.Narayanan, Kannan Vaidyanathan, D.M. Vasudevan Dept. of Biochemistry, Amrita Institute of Medical Sciences and Research Centre, AIMS- Ponekkara (PO) Cochin-682041, Kerala, India. AIM: - To diagnose the Neurometabolic Disorders in children. METHOD: - Patients from Amrita Institute of Medical Sciences and Research Centre are selected from 03.01.2008 to 02.10.2008. Study in 150 children (upper age limit 12 years) both males and females having symptoms suggestive of Neurometabolic Disorders (These include metabolic acidosis, increased anion gap, hypoketotic hypoglycemia, ketosis, ketonuria,lactic acidosis, hyperammonemia, abnormal hemogram, seizures, poor feeding, lethargy, failure to thrive, hypoglycemia, hepatomegaly)Patients who proved to have sepsis and other disorders of childhood will be excluded from the study even Neurometabolic Disorders are detected. Neurometabolic screening and TLC: - Manual screening tests (Rothera’s test, DNPH test, Ferric Chloride test, Ninhydrin test, Benedict’s test, glucose oxidase test, test for homogentisic acid) are used to detect the presence of abnormal metabolites in urine. Abnormal excretion of amino acids and organic acids in urine was detected by TLC. HPLC Analysis of urine Organic acids: - Deproteinised and desalted urine samples are subjected to HPLC quantification by Diode Array Detector. RESULTS: -150 urine samples are subjected for NeuroMetabolic Screening. Out of these 5.3%( N = 8) patients were from consanguinous families. Commom signs and symptoms were Seizures and delayed milestones (N=77), poor feeding (N=16), Lethargy (N= 11), metabolic acidosis (N= 9). 5 patients were expired during the study. Out of the 150 urine samples screened 40 samples were found +ve for Organic acids. They were further subjected to HPLC quantification. In 21 cases beta hydroxy butyric acid was higher than the normal limits. In 15 patients Methylmalonic acid level was higher (Methylmalonic aciduria), and in 16 patients the level of propionic acid was higher (Propionic aciduria). Molecular genetic study and enzyme assay are required for confirmation of the disease. DISCUSSION: -For evaluating a sick infant the first step is a through clinical examination including family history. Neurometabolic disorders are transmitted as autosomal recessive traits. The signs and symptoms observed was similar to that reported in literature. The most prevalent symptoms were delayed development, mental retardation lethargy. In the present study seizures, regression of milestones, poor feeding, failure to thrive were most common findings. Positive family history and consanguinity are important factors in predisposing neurometabolic disorders.