Last updated 2mo ago
A 7-year-old boy with behavior changes and declining school performance develops vision and hearing loss. MRI shows posterior white matter changes. He has adrenal insufficiency.
XLR; ABCD1 (ALDP peroxisomal transporter)
- Childhood cerebral ALD: 4-10 years, rapid neurological decline, death in ~2 years
- Adrenomyeloneuropathy (AMN): Adult males, spastic paraparesis, peripheral neuropathy
- Adrenal insufficiency only: May precede neurological symptoms
- Female carriers: May develop AMN-like symptoms in adulthood
- On RUSP
- Elevated VLCFA (very long-chain fatty acids), ABCD1 testing
- HSCT (early cerebral disease)
- Lorenzo's oil (prevention questionable)
- Adrenal replacement
- Gene therapy
ABCD1, "DeCemBAr 25th": ABCD spelled backwards is "DeCemBAr." Think about the day before and after Christmas: C24 and C26 are the VLCFA biomarkers for X-ALD. Also: "The Almighty was Born on Christmas Day."
"Veri long beta oxi in the peroxi": VLCFA cannot be transported across the peroxisome membrane for beta-oxidation, so they build up in adrenal glands (adrenal crisis), white matter of brain (leukodystrophy), and testes.
Part of HALO-M, the X-linked disorders: Hunter, Adrenoleukodystrophy, Lesch-Nyhan, OTC deficiency, Menkes.
This visual summarizes the X-ALD biomarkers (C26:0 and C24:0 fatty acids) and the "Christmas" mnemonic: ABCD spelled backwards is "DeCemBAr," and the days before and after Christmas (24th and 26th) give you the biomarker carbon chain lengths.
