ArticleOrphanet journal of rare diseases2025
Usefulness of levels of 2-methylbutyrylglycine and 2-ethylhydracrylic acid in urine for diagnosing 2-methylbutyrylglycinuria.
Article in Orphanet journal of rare diseases, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
7 authors.
Funding
Abstract
backgroundThe congenital disease 2-methylbutyrylglycinuria involves defective isoleucine metabolism and is currently diagnosed based on elevated levels of 2-methylbutyrylcarnitine/isovalerylcarnitine C5 in blood, followed by analysis of 2-methylbutyrylglycine (2-MBG) in urine at an early stage. However, 2-ethylhydracrylic acid (2-EHA) was reported as a more easily detected marker for 2-methylbutyrylglycinuria due to its larger volume in urine. Here we explored the usefulness of two urinary markers for diagnosing the condition.
methodsWe used electrospray-tandem mass spectrometry to assay levels of C5 and other acylcarnitines in blood and gas chromatography-mass spectrometry to assay levels of 2-MBG and 2-EHA in the urine of 12 individuals diagnosed with 2-methylbutyrylglycinuria based on ACADSB genotyping and in 166 controls. The diagnostic sensitivity and specificity of 2-MBG and 2-EHA were assessed based on receiver operating characteristic curves. Potential associations of levels of the two urinary markers with levels of C5 and other acylcarnitines in blood were explored using Pearson correlation analysis.
resultsUrine of the 12 individuals with 2-methylbutyrylglycinuria contained a 2-MBG level of 1.78-11.89 (reference range, 0-0) and a 2-EHA level of 37.80-373.13 (reference range, 0-28.69), but levels of both analytes were undetectable or barely detectable in the urine of the 166 controls. Both markers showed 100% diagnostic sensitivity, and 2-MBG showed slightly higher specificity than 2-EHA (2-MBA, 99.5%, 95%CI 0.970-1.00; 2-EHA, 97.8%, 95%CI 0.943-0.994). Levels of 2-MBG, but not 2-EHA, in urine showed a reliable Pearson correlation with levels of C5 in blood (R
conclusionThe urinary markers 2-MBG and 2-EHA show similar sensitivity for diagnosing 2-methylbutyrylglycinuria, but the lower specificity of 2-EHA and the fact that it can be elevated in several other congenital metabolic disorders means that it should be used as a diagnostic marker only in conjunction with other markers and clinical factors.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.