Biochemical contribution to diagnosis and study of a new case of D-glyceric acidemia/aciduria.

Abstract

During organic acid screening by gas chromatography/mass spectrometry, we detected a large peak corresponding to glyceric acid in a patient's urine sample. The D(+) configuration was demonstrated by a polarimetric method and by enzymatic stereospecificity of D-glycerate dehydrogenase (EC 1.1.1.29). We biochemically investigated this fifth reported case of D-glyceric acidemia. In our patient, loading tests with L-serine and fructose led to an increase of D-glyceric acid in both plasma and urine. Determination of other metabolites involved in D-glycerate metabolism revealed no abnormality in any sample examined. After comparing all our results with those of the preceding observations described in the literature, we suggest a possible enzymatic defect located on one of the metabolic pathways shared by fructose and L-serine, possibly at the level of hepatic D-glycerate kinase (EC 2.7.1.31). Nevertheless, a primary defect of L-serine catabolism cannot be entirely excluded.

d‐Glyceric acidaemia: clinical report and biochemical studies in a patient

“…Concentration of D-glyceric acid in the urine ranged from 3.62 to 7.24mmol/mmol creatinine (13-45mmol/L). Plasma concentration of D-glyceric acid ranged from 281#moI/L to 587#mol/L (Fontaine et al, 1989). As reported in our first paper (Fontaine et aI., 1989), L-serine oral loading test (200 mg/kg) led to a 4.5-fold increase of D-glyceric acid concentrations in the urine.…”

“…moderate mental retardation or speech delay), metabolic acidosis and microcephaly; or the absence of clinical problems. Biochemical investigations performed in these patients have suggested disturbed fructose or/and serine metabolism.We have previously described (Fontaine et al, 1989) biochemical investigations in a patient with D-glyceric acidaemia in whom a deficiency of D-glyeerate kinase has been demonstrated (Van Schaftingen, 1989). We report here the clinical presentation of the child, other biochemical studies and the results of a therapeutic trial with sodium benzoate.The patient, a girl (C.E.…”

“…We have previously described (Fontaine et al, 1989) biochemical investigations in a patient with D-glyceric acidaemia in whom a deficiency of D-glyeerate kinase has been demonstrated (Van Schaftingen, 1989). We report here the clinical presentation of the child, other biochemical studies and the results of a therapeutic trial with sodium benzoate.…”

Pitfalls in the diagnosis of glycine encephalopathy (non‐ketotic hyperglycinemia)

“…The rare metabolic disorder D-(+)-glyceric aciduria (MIM 220120) has also been included in the differential diagnosis of hyperglycinemia. 1 Only a handful of cases of D-glyceric aciduria have been reported, [47][48][49][50][51][52][53] one of which was in an Afghan hound. 53 The underlying defect is unclear, but deficiencies of D-glycerate dehydrogenase, 54 triokinase, 50 or D-glycerate kinase 52,55 have been proposed.…”

D-Glyceric Aciduria in a Six-Month-Old Boy Presenting with West Syndrome and Autistic Behaviour

“…Urinary organic acid analysis (GC-MS) revealed increased glyceric acid excretion (76.6 mmol/mol creatinine; normal: < 9), whereas urinary oxalate excretion and renal ultrasound were normal. Analysis of the optical form of the glyceric acid by a polarimetric method supported the diagnosis of D-glyceric aciduria [5]. EEG revealed bilateral hemispheric epileptiform activity posteriorly especially dominant at the left side and a hypsarrhythmia pattern.…”