2026 ICD-10-CM Diagnosis Code G93.49Other encephalopathy

AHRQ’s CCSR groups this code into broader clinical categories.

• Adult-Onset Leukoencephalopathy with Axonal Spheroids and Pigmented Glia|ALSP|HDLS|Hereditary Diffuse Leukoencephalopathy with Spheroids|POLD|Pigmentary Orthochromatic Leukodystrophy

  a rapidly progressive neurodegenerative disorder, caused by mutations in the colony-stimulating factor 1 receptor (csf1r) gene, that presents in adulthood with a variety of neuropsychiatric and motor disturbances. hallmark features include diffuse myelin loss and axonal destruction, neuroaxonal spheroids, and pigmented macrophages and other glia.

• Grade 1 Leukoencephalopathy, CTCAE|Grade 1 Leukoencephalopathy

  asymptomatic; small focal t2/flair hyperintensities; involving periventricular white matter or <1/3 of susceptible areas of cerebrum +/- mild increase in subarachnoid space (sas) and/or mild ventriculomegaly

• Grade 2 Leukoencephalopathy, CTCAE|Grade 2 Leukoencephalopathy

  moderate symptoms; focal t2/flair hyperintensities, involving periventricular white matter extending into centrum semiovale or involving 1/3 to 2/3 of susceptible areas of cerebrum +/- moderate increase in sas and/or moderate ventriculomegaly

• Grade 2 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 2 Reversible posterior leukoencephalopathy syndrome

  moderate symptoms; limiting instrumental adl

• Grade 3 Leukoencephalopathy, CTCAE|Grade 3 Leukoencephalopathy

  severe symptoms; extensive t2/flair hyperintensities, involving periventricular white matter involving 2/3 or more of susceptible areas of cerebrum +/- moderate to severe increase in sas and/or moderate to severe ventriculomegaly

• Grade 3 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 3 Reversible posterior leukoencephalopathy syndrome

  severe symptoms; limiting self care adl; hospitalization

• Grade 4 Leukoencephalopathy, CTCAE|Grade 4 Leukoencephalopathy

  life-threatening consequences; extensive t2/flair hyperintensities, involving periventricular white matter involving most of susceptible areas of cerebrum +/- moderate to severe increase in sas and/or moderate to severe ventriculomegaly

• Grade 4 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 4 Reversible posterior leukoencephalopathy syndrome

  life-threatening consequences

• Grade 5 Leukoencephalopathy, CTCAE|Grade 5 Leukoencephalopathy

  death

• Grade 5 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 5 Reversible posterior leukoencephalopathy syndrome

  death

• Leukoencephalopathy

  white matter changes first described in children with leukemia, associated with radiation and chemotherapy injury, often associated with methotrexate; pathologically characterised by diffuse reactive astrocytosis with multiple areas of necrotic foci without inflammation.

• Leukoencephalopathy with Ataxia|CC2L|CLCN2-Related Leukoencephalopathy|LKPAT

  an autosomal recessive condition caused by mutation(s) in the clcn2 gene, encoding chloride channel protein 2. it is characterized by variable clinical features including mild cerebellar ataxia, chorioretinopathy, visual field defects, and headaches. a characteristic pattern of white matter abnormalities is evident on mri.

• Leukoencephalopathy with Brainstem and Spinal Cord Involvement and Lactate Elevation|LBSL

  an autosomal recessive condition caused by mutation(s) in the dars2 gene, encoding aspartate--trna ligase, mitochondrial. it is characterized by slowly developing progressive cerebellar ataxia, spasticity, dorsal column dysfunction, and may also include a mild cognitive deficit or decline.

• Leukoencephalopathy with Vanishing White Matter

  a rare, progressive neurological disorder inherited in an autosomal recessive pattern. it is caused by mutations in the eif2b1, eif2b2, eif2b3, eif2b4, and eif2b5 genes, resulting in deterioration of central nervous system's white matter. usually, there are no signs and symptoms of the disorder at birth. during early childhood, affected individuals develop spasticity and ataxia which may be associated with deterioration of the metal function. examination of the brain at autopsy reveals normal gray matter while the white matter is soft and gelatinous with numerous small cavities.

• Leukoencephalopathy, CTCAE|Leukoencephalopathy|Leukoencephalopathy

  a disorder characterized by diffuse reactive astrocytosis with multiple areas of necrotic foci without inflammation.

• Progressive Multifocal Leukoencephalopathy|PML

  a progressive demyelination within the central nervous system associated with reactivation of a latent jc virus infection.

• Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Reversible Posterior Leukoencephalopathy Syndrome|Reversible posterior leukoencephalopathy syndrome

  a disorder characterized by headaches, mental status changes, visual disturbances, and/or seizures associated with imaging findings of posterior leukoencephalopathy. it has been observed in association with hypertensive encephalopathy, eclampsia, and immunosuppressive and cytotoxic drug treatment. it is an acute or subacute reversible condition. also known as posterior reversible encephalopathy syndrome (pres).

• Reversible Posterior Leukoencephalopathy Syndrome|PRES|Posterior Reversible Encephalopathy Syndrome|RPLE|Reversible Occipital Parietal Encephalopathy|Reversible Posterior Cerebral Edema Syndrome|Reversible posterior leukoencephalopathy syndrome

  an acute or subacute reversible condition characterized by headaches, mental status changes, visual disturbances, and seizures associated with imaging findings of posterior leukoencephalopathy. it has been observed in association with hypertensive encephalopathy, eclampsia, and immunosuppressive and cytotoxic drug treatment.

• Obstructive Sleep Apnea Syndrome

  a disorder characterized by recurrent episodic disruptions of breathing during sleep. it is caused by the intermittent relaxation of pharyngeal muscles leading to the narrowing or complete blockage of the upper airway. this results in compensatory arousal from sleep to breathe again. an anatomically narrow airway from body habitus or enlarged pharyngeal structures may also predispose to obstruction. clinical presentation usually includes snoring, daytime sleepiness, difficulty concentrating and fatigue. clinical course may progress to chronic hypoxemia with cardiovascular and cerebrovascular sequelae.

• Progressive Muscular Atrophy

  a rare, milder form of amyotrophic lateral sclerosis. it is characterized by a slowly progressive clinical course. signs and symptoms include muscle weakness, atrophy, and fasciculation.

• GAIA Level 1 Neonatal Encephalopathy|Global Alignment of Immunization safety Assessment in pregnancy Level 1 Neonatal Encephalopathy|Level 1 Neonatal Encephalopathy

  gaia level 1 neonatal encephalopathy is defined by three criteria: first, a newborn infant (1-28 days of life) born at or beyond 35 weeks of gestation; second, an abnormal level of alertness or seizures; third, difficulty with initiating and maintaining respiration; fourth, depression of muscle tone.

• GAIA Level 2 Neonatal Encephalopathy|Global Alignment of Immunization safety Assessment in pregnancy Level 2 Neonatal Encephalopathy|Level 2 Neonatal Encephalopathy

  gaia level 2 neonatal encephalopathy is defined by three criteria: first, a newborn infant (1 to 28 days of life) born at or beyond 35 weeks of gestation; second, an abnormal level of alertness or seizures; third, either difficulty with initiating and maintaining respiration or depression of muscle tone.

• GAIA Level 3 Neonatal Encephalopathy|Global Alignment of Immunization safety Assessment in pregnancy Level 3 Neonatal Encephalopathy|Level 3 Neonatal Encephalopathy

  gaia level 3 neonatal encephalopathy is defined by three criteria: first, a newborn infant (1-28 days of life) born at or beyond 35 weeks of gestation; second, an abnormal level of alertness or seizures; third, none of the following: a) difficulty with initiating or maintaining respiration; b) depression of muscle tone.

• GAIA Neonatal Encephalopathy Level of Diagnostic Certainty Terminology|Global Alignment of Immunization safety Assessment in pregnancy Neonatal Encephalopathy Level of Diagnostic Certainty

  a subset of terminology related to neonatal encephalopathy, developed by the global alignment of immunization safety assessment in pregnancy consortium to aid in monitoring and improving fetal and maternal outcomes.

• GAIA Neonatal Encephalopathy Level of Diagnostic Certainty|Global Alignment of Immunization safety Assessment in pregnancy Neonatal Encephalopathy Level of Diagnostic Certainty|Neonatal Encephalopathy Level of Diagnostic Certainty

  a classification of maternal and fetal outcomes relating to neonatal encephalopathy, developed by the global alignment of immunization safety assessment in pregnancy, based on the extent to which the diagnosis has been confirmed.

• Neonatal Encephalopathy

  abnormal functioning of the central nervous system in the newborn period that may be due to a variety of etiologies including hypoxia/ischemia, metabolic disturbance, or infection.

• Severe Neonatal Encephalopathy Due to MECP2 Mutations

  an x-linked recessive condition caused by mutation(s) in the mecp2 gene, encoding methyl-cpg-binding protein 2. it is characterized by severe neonatal encephalopathy.

• Autosomal Recessive Cerebral Arteriopathy with Subcortical Infarcts and Leukoencephalopathy|CARASIL

  an autosomal recessive condition caused by mutation(s) in the htra1 gene, encoding serine protease htra1. it is characterized by subcortical infarcts and leukoencephalopathy resulting in progressive motor dysfunction and dementia.

• Early-Onset Progressive Encephalopathy with Brain Edema and/or Leukoencephalopathy 2|NAD(P)HX Dehydratase Deficiency|PEBEL2

  an autosomal recessive condition caused by mutation(s) in the naxd gene, encoding atp-dependent (s)-nad(p)h-hydrate dehydratase.

• Grade 2 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 2 Reversible posterior leukoencephalopathy syndrome

  moderate symptoms; limiting instrumental adl or mild/moderate impact on age-appropriate normal daily activity (pediatric)

• Grade 3 Reversible Posterior Leukoencephalopathy Syndrome, CTCAE|Grade 3 Reversible posterior leukoencephalopathy syndrome

  severe symptoms; hospitalization; limiting self-care adl or severe impact on age-appropriate normal daily activity (pediatric)

• Leukoencephalopathy, Developmental Delay, and Episodic Neurologic Regression Syndrome|Leuden Syndrome

  an autosomal dominant syndromic condition caused by mutation(s) in the eif2ak2 gene encoding interferon-induced, double-stranded rna-activated protein kinase. it is characterized by hypotonia, gait difficulties or ataxia, poor or absent speech with dysarthria, and variable motor abnormalities, including spasticity, dystonia, extrapyramidal signs, and tremor.

• Polycystic Lipomembranous Osteodysplasia with Sclerosing Leukoencephalopathy 2|PLOSL2

  an autosomal recessive condition caused by mutation(s) in the trem2 gene, encoding triggering receptor expressed on myeloid cells 2. it is characterized by presenile dementia with leukoencephalopathy and calcification of the basal ganglia.

Brain Diseases

Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.

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