Caring for someone with this diagnosis? Eleplan keeps diagnoses, medications, documents and every specialist in one plan.
Start free with EleplanHSD10 disease, infantile type
ORPHA:391428Clinical subtype
Also called 2-methyl-3-hydroxybutyric aciduria, classic type · 2-methyl-3-hydroxybutyric aciduria, infantile type · 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency, classic type · 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency, infantile type · HSD10 deficiency, classic type · HSD10 deficiency, infantile type · HSD10 disease, classic type · MHBD deficiency, classic type · MHBD deficiency, infantile type
What it is
A clinical subtype of HSD10 disease, a rare neurometabolic disorder. Affected boys may show lethargy, poor feeding and evidence of mitochondrial dysfunction in the newborn period, with subsequent mild developmental delay and abnormal muscle tone. Hallmark of the disease is progressive neurodegeneration and cardiomyopathy, which usually manifests between ages 6 months and 2 years with developmental regression, progressive visual and hearing loss, epilepsy and other neurological symptoms, and severe cardiomyopathy. Laboratory investigations show signs of mitochondrial dysfunction, and increased urinary excretion of specific isoleucine metabolites. The disease is often fatal around 2-4 years of age.
Key facts
- Age of onset
- Infancy, Neonatal
- Inheritance
- X-linked dominant
- Classified as
- Clinical subtype
Recorded for the broader condition
- Prevalence
- <1 / 1 000 000HSD10 disease
Orphanet records these for the broader condition rather than for this specific form. They are a starting point, not a figure for this subtype — subtypes often differ, and some are defined by being rarer than the condition they sit under.
Signs and symptoms
Very common80–99%
4Common30–79%
13Sometimes5–29%
34- Abnormal basal ganglia morphology
- Abnormal facial shape
- Abnormality of the lower urinary tract
- Absent speech
- Cardiomegaly
- Choreoathetosis
- Cyanosis
- Diffuse cerebral atrophy
and 26 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
Powered by Eleplan
A rare diagnosis is just the start. Eleplan keeps the whole care plan in one place.
Diagnoses, medications, documents, appointments, and the whole care team — organized and always in sync, so you are not retelling the same story to every new specialist. With Ellie, your AI care assistant, on top of it. Free to start.