Organic acid disorders detected by urine organic acid analysis: Twelve cases in Thailand over three-year experience

Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Clinica Chimica Acta (Impact Factor: 2.82). 07/2008; 392(1-2):63-8. DOI: 10.1016/j.cca.2008.02.015
Source: PubMed


Disorders of organic acid (OA) metabolism are generally detected by qualitative analysis of urine organic acids by gas chromatography/mass spectrometry (GC/MS) which was well established in developed countries since 1980s. Confirmation of the diagnosis of organic acid disorders by OA analysis, enzyme analysis and molecular study is a difficult task in developing countries.
During 2001-2004, we had analysed 442 urine samples in 365 patients and identified 12 cases of organic acid disorders.
We identified the following disorders: alkaptonuria (ALK)=1, isovaleric acidemia (IVA)=3, propionic acidemia (PA)=2, methylmalonic acidemia (MMA)=3, glutaric aciduria, type I (GA-I)=1, multiple carboxylase deficiency (MCD)=1, and glutaric acidemia, type II (GA-II)=1.
OA disorders had never been diagnosed in Thailand before, until GC/MS technology was introduced to Thailand in 2001. Urine OA analysis also provided a diagnostic clue to other inborn errors of metabolism including amino acid disorders, urea cycle disorders, disorders of carbohydrate metabolism, and mitochondrial fatty acid oxidation disorders. Since then, we were able to diagnose numerous disorders, which led to prompt treatment and better outcome in our patients.

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    • "Please cite this article as: Karam PE, et al, Diagnostic challenges of aminoacidopathies and organic acidemias in a developing country: A twelveyear experience, Clin Biochem (2013), that from Kuwait (4.4%) [26]. Reported yields for urine organic acid chromatography from other countries ranged from 2.4% in Japan [27] to 8% in Thailand [28] with intermediate values in Brazil (3.2%) [29] which is comparable to ours (3.9%) and slightly higher in Asia (5.6%) [27]. "
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    ABSTRACT: The study of inherited metabolic disorders (IMD) in Thailand is in its infancy when compare with developed countries. Prior to 1987, majority of these disorders were clinically diagnosed since there were only a handful of clinicians and scientists with expertise in inborn errors of metabolism, lack of well-equipped laboratory facilities and government support. In developing countries, inherited metabolic disorders are not considered a priority due to the prevalence of infectious diseases such as HIV infection and congenital infections. A multicentre survey conducted in 1994 and 2001 revealed the existence of numerous cases of IMD from all over the country. Case reports and publications on IMD in Thai (and international) medical journals in past 20 years had undoubtedly raised its awareness among Thai paediatricians and scientists. In 2001, the Genetic Metabolic Centre was first established in Siriraj Hospital Faculty of Medicine, Thailand. Numerous new cases of IMD had been identified since then.
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