Neuroimaging Cranial computed topography, magnetic resonance imaging, and flurodeoxyglucose positron emission topography are just some of the neuroimaging modalities that have been used to diagnose patients with<unk> . On the basis of 29 previously published cases that had imaging results available, there were some common abnormalities found. These included increased T2-weighted signal abnormalities involving the globus pallidi bilaterally and symmetrically as well as the presence of subcortical white matter. Similar abnormalities have been identified in the brainstem and cerebellar dentate nucleus. Signal intensity on a T2 image may be a result of edema or an inflammatory response. Because this type of imaging is a water detecting sequence, any form of calcification or mineralization would also appear dark, thus explaining why accumulation of extra blood or fluid would appear bright on a T2 image. Another explanation for signal intensity may be demyelination since the globus pallidi are traversed by a number of myelinated axons, thus confirming Ren and Mody's 2003 work proving that repeated exposure of GHB to MAP kinase affected myelin expression, thus causing the numerous neurological dysfunctions seen in<unk>  patients. Ultimately, because the globus pallidus is intimately linked with the basal ganglia and thalamus, it would be expected that some of the motor dysfunctions seen in SSADH patients such as ataxia and hyporeflexia would be common. Laboratory Detection of the disorder is possible with an organic acid analysis of the urine. Patients with<unk>  will excrete high levels of GHB but this can be difficult to measure since GHB has high volatility and may be obscured on gas chromatography or mass spectrometry studies by a high urea peak. Other GABA metabolites can also be identified in urine such as glycine. Finally,<unk><unk>  dehydrogenase levels can be measured in cultured leukocytes of the patient. This occurs due to the accumulation of 4,5-dihydroxyhexanoic acid which is normally undetectable in mammalian tissues but is characteristic of<unk> . This agent can eventually compromise the pathways of fatty acid, glycine, and pyruvate metabolism, and then become detectable in patients' leukocytes. Such enzyme levels can also be compared to non-affected parents and siblings.
Succinic semialdehyde dehydrogenase deficiency
Pyruvate dehydrogenase deficiency
2-Methylbutyryl-CoA dehydrogenase deficiency
3-Methylcrotonyl-CoA carboxylase deficiency
Malonyl-CoA decarboxylase deficiency
Glutaminase deficiency
Pyruvate kinase deficiency
Succinyl-CoA:3-oxoacid CoA transferase deficiency