The clinical presentation of central pontine myelinolysis is variable. Patients may be asymptomatic, or have mild to severe symptoms, including rapid onset of pseudobulbar symptoms (e.g., difficulty swallowing or speaking), paraparesis, quadriparesis, confusion, psychiatric symptoms (e.g., delirium or hallucinations), "locked-in syndrome," in which there is paralysis of the lower limb musculature and cranial nerves resulting in a lack of expressive communication ability, although the intellectual activity is unaffected [1].

The symptoms may appear with a biphasic course, consisting of seizures and/or encephalopathy, with a period of improvement, followed by deterioration consisting of spastic quadriplegia, dysarthria, dysphagia, and occasionally oculomotor abnormalities such as horizontal gaze paralysis [2].

• High Fever

  A 78-year-old Japanese woman presented to a neighborhood clinic with persistent high fever, edema, and general weakness. [ncbi.nlm.nih.gov]

• Dysphagia

  English central pontine myelinolysis demyelination disease that is characterized by severe damage to the myelin sheath of the pons' nerve cells and has symptom acute paralysis, has symptom dysphagia, and has symptom dysarthria central pontine myelinolysis [wikidata.org]

  We report a very case of a patient with dysarthria, dysphagia and psychiatric symptoms including abnormal behavior starting after alcohol withdrawal, with radiological evidence of CPM and EPM. [ncbi.nlm.nih.gov]

  Because of his dysphagia, he was kept on a Lavin tube and was treated with conservative care, including a thiamine supplement. [doi.org]

• Progressive Dysphagia

  Case Report A 47-year-old man was admitted to the hospital with complaints of progressive dysphagia and dysarthria for a week, and this occurred just 2 days after he stopped drinking. His medical history was unremarkable. [doi.org]

• Emotional Lability

  Case 1: 24-year-old male, known alcoholic, was admitted with left hemiplegia and features of bulbar and pseudobulbar palsy with dysphagia, dysarthria and emotional lability. [endocrine-abstracts.org]

  lability ( pseudobulbar affect ), with other more variable neurological features associated with brainstem damage. [en.wikipedia.org]

  Neurological examination was significant for emotional lability, dysarthria, and gait ataxia with bilateral dysmetria. Motor examination showed normal tone, power grade 5 in all limbs, absent knee and ankle jerks, and flexor plantar response. [smj.org.sg]

• Dysarthria

  There was little improvement in the dysarthria or psychiatric symptoms in the first month. [ncbi.nlm.nih.gov]

  He only displayed bulbar palsy and dysarthria. [doi.org]

• Altered Mental Status

  Although her bicarbonate deficit was 365 mEq, we treated her with an overdose of intravenous sodium bicarbonate, 480 mEq for 24 hours, due to the severity of her acidemia and her altered mental status. [ncbi.nlm.nih.gov]

  Some of the signs and symptoms include: Difficulty in speaking Difficulty in swallowing Double vison Muscle cramps Convulsions Hallucinations Poor reflexes Paralysis of various parts of the body Loss of sensation in various parts of the body Altered mental [dovemed.com]

  mental status Specialty Neurology Central pontine myelinolysis ( CPM ) is a neurological condition involving severe damage to the myelin sheath of nerve cells in the pons (an area of the brainstem ). [en.wikipedia.org]

• Spastic Quadriplegia

  Key features of the neurologic exam include confusion, horizontal gaze paralysis, and spastic quadriplegia. [emedicine.com]

  The symptoms may appear with a biphasic course, consisting of seizures and/or encephalopathy, with a period of improvement, followed by deterioration consisting of spastic quadriplegia, dysarthria, dysphagia, and occasionally oculomotor abnormalities [symptoma.com]

  They published their findings in 1958, observing that patients who suffered from alcoholism or malnutrition developed spastic quadriplegia, pseudobulbar palsy, and varying degrees of encephalopathy or coma from acute, noninflammatory demyelination that [coolmristuff.wordpress.com]

  It is characterized by spastic quadriplegia, pseudobulbar palsy and encephalopathy. It is observed in patients with severe hyponatremia, particularly when the hyponatremia is corrected too rapidly. [fpnotebook.com]

• Lethargy

  A 26-year-old man with a history of chronic alcohol abuse presented with dysarthria, lethargy, and horizontal nystagmus. [dx.doi.org]

  Common symptoms included lethargy and dysarthria. Five of the 6 patients had chronic alcoholism. All had improvements in their clinical conditions upon hospital discharge. [ncbi.nlm.nih.gov]

  Acute symptoms Paralysis (can affect two or all of the limbs) Difficulties swallowing (dysphagia) and speaking (dysarthria) Problems with the vision (diplopia) Loss of consciousness Confusion and delirium Balance problems (unstable gait) Hallucinations Lethargy [mddk.com]

  Signs and symptoms include confusion, lethargy, dysarthria, dysphagia, tremor, and profound bilateral weakness that may progress to spastic quadriplegia and “locked in syndrome.” [ijam-web.org]

• Stupor

  Large lesions cause spastic bulbar paralysis, quadriplegia, stupor or coma, or the locked-in syndrome, developing in a background of severe electrolyte abnormalities. [neuropathology-web.org]

  Clinical manifestations of CPM include stupor and spastic tetraparesis[ 51 ]. Neuroimaging studies typically show area of T2 hyperintensity on MRI imaging in central pons[ 19 ]. [dx.doi.org]

  The Diagnosis of Stupor and Coma. FA Davis: Philadelphia, 1966. 2.Recommendations for use of uniform nomenclature pertinent to patients with severe alterations of consciousness. American Congress of Rehabilitation Medicine. [consultant360.com]

Workup of central pontine myelinolysis consists of a history, physical exam, laboratory testing, and imaging. Patients with a history of rapid correction of severe hyponatremia (plasma serum level <120 mq/L persisting for two or more days, that has been corrected at a rate greater than 8 mq/L in 48 hours), patients with liver disease or alcohol abuse should be considered at high-risk for central pontine myelinolysis [3] [4]. During the neurologic exam, the clinician should assess signs of confusion, occulomotor dysfunction (e.g., horizontal gaze paralysis), impaired speech or swallowing, and signs of spastic quadriplegia such as limb weakness, increased tonicity of the limb muscles, and hyperreflexia). The primary laboratory test consists of a chemistry panel (sodium, potassium, chloride, bicarbonate, glucose, creatine, and BUN). Liver function test can also be performed when clinically indicated.

Computed tomography (CT) and magnetic resonance imaging (MRI) have been used to aid in the diagnosis [5] [6] [7] [8]. Imaging test results may be normal during the early stages of the disease (through two weeks); after this period imaging abnormalities indicative of central pontine myelinolysis emerge. MRI is more sensitive for diagnosing abnormalities than CT scan [9] [10]. Comparison of changes between earlier and later CT or MRI scans is also useful.

CT scan images are prone to streak artifact in the region of the pons (and thus not as sensitive as MRI). CT scan may reveal low attenuation crossing the midline in the lower pons.

On T2-weighted MRI scans, areas of demyelination are marked by hyperintense and bright areas. T1 signal may be mildly or moderately hypointense; fluid attenuation inversion recovery (FLAIR) signal will usually appear hyperintense. A classic trident shaped pattern is indicative of ventrolateral pons, corticospinal tract, and tegmentum sparing. Extrapontine lesions are usually bilateral; they are commonly found on the cerebellar peduncles, globus pallidus, lateral geniculate body, thalamus, and putamen [5] [11].

Cerebral spinal fluid evaluation may show an elevated opening pressure, mononuclear pleocytosis, or an elevated protein level.

Few advanced neuroimaging studies like positron emission tomography have been studied for its efficacy in the diagnosis of central pontine myelinosis; studies have shown a high FDG-18 uptake initially, followed by decreased uptake in affected regions [12].

Electroencephalography (EEG) can be used to supplement imaging results, particularly when neuroimaging is not definitive. EEG usually reveals diffuse bihemispheric slowing in patients with central pontine myelinolysis.

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