Delayed Post-hypoxic Leukoencephalopathy (DPHL or Grinker myelinopathy) is a rare condition where patients recovering from an anoxic/hypoxic brain injury develops new neurological symptoms 2-4 weeks after the initial injury. Why is there a delay in symptoms?
1 Answer
The brain is made up of oxygen-demanding gray matter and myelin-covered white matter.
Hypoxic events initially damage the gray matter, but myelin is spared. However, new myelin secretion requires ATP-dependent enzymes which is impaired by hypoxic event. Since myelin takes about ~20 days to cycle, this coincides with the biphasic presentation of DPHL. Another theory is that oligodendrocytes (myelin-secreting cells) might have delayed apoptosis after hypoxic event, also leading to lack of new myelin formation once the old myelin degenerates.
Source:
Beeskow AB, Oberstadt M, Saur D, Hoffmann KT, Lobsien D. Delayed Post-hypoxic Leukoencephalopathy (DPHL)-An Uncommon Variant of Hypoxic Brain Damage in Adults. Front Neurol. 2018;9:708. Published 2018 Aug 27. doi:10.3389/fneur.2018.00708