FDG PET/CT Aiding in Early Diagnosis of Central Pontine Myelinolysis.

ABSTRACT: We report a 70-year-old man with central pontine myelinolysis who presented in the emergency department with recent onset altered sensorium and tremors (Glasgow Coma Scale score, 13). Laboratory findings revealed hyponatremia and hypokalemia. MRI brain was unremarkable. Subsequently, patient was referred for FDG PET/CT to rule out malignancy or paraneoplastic syndrome. FDG PET revealed focal radiotracer uptake in the pons without any underlying CT abnormality consistent with central pontine myelinolysis, thus aiding in early diagnosis where conventional imaging modality was unremarkable.

Acquired laryngomalacia as a cause of post-extubation respiratory failure in patient with postoperative seizure and central pontine myelinolysis after craniotomy.

Background : Laryngomalacia is a congenital abnormality of the larynx that commonly occurs in children and rarely in adults. We report the first case of acquired laryngomalacia mainly due to postoperative seizure and central pontine myelinolysis after scheduled craniotomy. Case presentation : A 69-year-old man was admitted to the hospital for elective craniotomy for craniopharyngioma. After the surgery, he developed refractory seizure and required intubation and mechanical ventilation in the intensive-care unit (ICU). After treatment for the seizure, he was extubated. However, immediately after extubation, he developed stridor and respiratory retraction. We performed fiberoptic laryngoscopy and confirmed that the epiglottis had collapsed into the posterior wall of the pharynx during inspiration, which was suspected to be laryngomalacia. He received invasive mechanical ventilation for two days following re-extubation. After the second extubation, he developed stridor again due to acquired laryngomalacia. Six days later, his respiratory condition had worsened, and he received re-intubation and tracheostomy. After ICU discharge, central pontine myelinolysis was diagnosed by magnetic resonance imaging. Conclusions : Adult-onset laryngomalacia is a rare cause of upper airway obstruction but should be considered as a cause of postoperative extubation failure. We should not delay performing fiberoptic laryngoscopy to evaluate this pathology and provide optimal treatment. J. Med. Invest. 69 : 316-319, August, 2022.

Extrapontine Myelinolysis and Reversible Parkinsonism After Hyponatremia Correction in a Case of Pituitary Adenoma: Hypopituitarism as a Predisposition for Osmotic Demyelination.

BACKGROUND: Osmotic demyelination syndrome commonly follows rapid correction of hyponatremia. Although pons is a common location, extrapontine locations, such as striatum and thalamus, have been reported. CASE DESCRIPTION: A 48-year-old woman presented with masked facies, shuffling gait, and pill-rolling tremors suggestive of acute-onset parkinsonism. Hyponatremia was diagnosed following a bout of diarrhea, which was corrected with hypertonic saline. Magnetic resonance imaging of the brain showed a giant pituitary adenoma. Hyperintensities on T2-weighted imaging were also seen at the level of pons and bilateral striatum. Central pontine myelinolysis and extrapontine myelinolysis were diagnosed. Hormonal assay showed hypocortisolism, secondary hypothyroidism, and hypogonadism. The patient was started on levodopa-carbidopa, steroids, and thyroxine. She underwent transnasal pituitary adenoma excision. At 6 months postoperatively, she had recovered completely with normal gait. Repeat imaging showed complete resolution of myelinolysis. At 36 months, she continued to have hypocortisolism and hypothyroidism requiring replacement. CONCLUSIONS: Extrapontine myelinolysis with parkinsonism and asymptomatic central pontine myelinolysis is rare with few cases described in the literature. Our patient had a pituitary adenoma with hyponatremia requiring sodium correction, and we believe that hypopituitarism might have predisposed her to osmotic demyelination. We reviewed relevant literature on extrapontine myelinolysis in suprasellar tumors and the pathophysiology. Hypopituitarism is an underrecognized cause of hyponatremia. When treating a patient with hyponatremia, knowing the pituitary function status is a prerequisite for the physician to prevent osmotic demyelination syndrome.

Diffuse large B-cell lymphoma presenting with central pontine myelinolysis: a case report.

INTRODUCTION: The most common cause of central pontine myelinolysis is an overly rapid correction of hyponatremia, although it can also occur in patients with any condition leading to nutritional or electrolyte stress. We report a case of diffuse large B-cell lymphoma with central pontine myelinolysis developing at the onset of disease. To the best of our knowledge, hematological malignancies presenting with central pontine myelinolysis have been rarely reported, especially in previously untreated patients, as in our case report. CASE PRESENTATION: A 78-year-old Japanese woman presented to a neighborhood clinic with persistent high fever, edema, and general weakness. Despite the absence of specific neurological findings, brain magnetic resonance imaging showed an abnormal lesion in the central pons area of her brain (hyperintense on T2-weighted and hypointense on T1-weighted sequences), compatible with central pontine myelinolysis. She was admitted to our emergency department in a state of shock one month later. The results of her blood tests showed greatly elevated C-reactive protein and lactate dehydrogenase levels. She had severe hypoalbuminemia and mild hyponatremia, and showed signs of disseminated intravascular coagulation. Mild bilateral pleural effusion, prominent subcutaneous edema, and splenomegaly were detected on her systemic computed tomography scan. Her body fluid cultures did not show signs of infection and her spinal aspiration did not show pleocytosis or abnormal cells. A diagnosis of diffuse large B-cell lymphoma was made based on the results of her bone marrow examination. As she was critically ill before the diagnosis was made, she was treated with methylprednisolone pulse therapy, followed by systemic chemotherapy (rituximab with modified THP-COP regimen, including cyclophosphamide, pirarubicin, vindesine, and prednisolone), which resulted in complete remission and recovery without any neurological defects, and resolution of her abnormal findings on magnetic resonance imaging. CONCLUSIONS: Central pontine myelinolysis is a serious condition that may result in neuropathological sequelae and mortality, and clinicians should be aware of its potential presence in patients with malignancies.

Central pontine myelinolysis presenting with tremor in a child with celiac disease.

A 4-year-old boy presented with a history of tremor for 7 days. He also had recurrent diarrhea for the previous 1 year, and poor weight gain. Magnetic resonance of the brain was suggestive of central pontine myelinolysis. There was no evidence of electrolyte abnormalities. The serum tissue transglutaminase level was markedly elevated, and the duodenal biopsy revealed features of celiac disease. The patient was started on gluten-free diet. The tremor resolved within 3 months. Repeat imaging of the brain done 3 months after starting gluten-free diet showed complete resolution of the lesion. This case highlights the unusual presentation of central pontine myelinosis as tremor in a malnourished child with celiac disease.

Central pontine myelinolysis in advanced HIV infection with tuberculosis and multicentric Castleman's disease.

We present a case of central pontine myelinolysis (CPM) in a patient with advanced HIV infection and miliary tuberculosis. While hospitalized the patient developed an unusual ataxic variant of CPM with full clinical recovery. Follow-up imaging revealed resolution of pontine lesions. To our knowledge, this is the first report of a clinical and radiological recovery from CPM in advanced HIV disease. Our report extends our knowledge of neurological presentations in patients with advanced HIV infection. It highlights the importance of considering CPM in patients with advanced HIV disease presenting with an ataxic syndrome, even in the absence of an electrolyte derangement.

Central pontine myelinolysis with meticulous correction of hyponatraemia in chronic alcoholics.

Central pontine myelinolysis is a demyelinating disorder that arises due to osmolar disturbances in the cerebral microenvironment characterised by loss of the myelin sheath of neurons. The diffusion-weighting imaging sequence of MRI is the most sensitive diagnostic imaging modality for myelinolysis. The rapid correction of hyponatraemia by >20-25 mmol/L/48 h has been known for a long time as a prime cause of osmotic demyelination. Various other comorbidities in hyponatraemic patients are well known that can lead to osmotic demyelination such as alcoholism, hypoxaemia, severe liver disease, malignancy, burns, liver transplantation and malnutrition. Chronic alcohol abusers with additional liver disease and malnutrition have altered osmotic equilibrium at baseline that predisposes them to osmotic demyelination. We suggest a more cautious and meticulous approach should be followed in these patients to avoid the dreaded complication.

Management of hyponatraemia.

Hyponatraemia (serum sodium level < 135 mmol/litre) is the most common electrolyte abnormality among hospitalized patients. A prevalence rate as high as 15-30% has been reported among patients admitted to acute and intensive care units (Hoorn et al, 2004; Jaber et al, 2006). Evidence suggests an increase in mortality associated with even a mild degree of hyponatraemia (Waikar et al, 2009). Besides its significance as a potential cause of morbidity and mortality, hyponatraemia could also serve as a useful indicator for undiagnosed underlying pathology such as endocrine disorders or malignancy. A systematic approach towards the clinical assessment and interpretation of biochemical abnormalities is vital to facilitate the diagnosis and management of hyponatraemia. The optimal treatment of hyponatraemia should take into account its severity, duration and mode of clinical presentation. Overzealous correction could result in irreversible neurological complications.

Central pontine and extrapontine myelinolysis despite careful correction of hyponatremia: clinical and neuropathological findings of a case.

We report clinical, radiological and pathological findings in a patient with central pontine and extrapontine myelinolysis. The patient was a 61-year-old woman who had a radical mastectomy for breast cancer. Based on clinical evidence, acute hyponatremia had set in only a few days before onset of symptoms. The patient's disease progressed in two stages and became more severe during slow hyponatremia correction after 9 days from onset. Diffusion MRI provided early evidence of neurological lesions. In spite of a therapeutic attempt, the patient died unexpectedly 18 days after onset of her neurological disease due to massive pulmonary embolism. Histologically, our findings confirmed that the major features of central pontine myelinolysis in the acute stage are demyelination, the presence of large amounts of macrophages with no lymphocytic inflammatory reaction, and moderate astrocytosis. It is interesting to note that a monotypic immunological reaction persisted 19 days after radiological demonstration of parenchymal alterations.

Risk factors for central pontine and extrapontine myelinolysis following orthotopic liver transplantation.

BACKGROUND: Central pontine myelinolysis (CPM)/extrapontine myelinolysis (EPM) is one of the most serious neurological complications that can occur after orthotopic liver transplantation (OLT). We analyzed the risk factors for CPM/EPM in OLT patients. METHODS: We retrospectively reviewed the records of 1,247 patients who underwent OLT between 1992 and 2005. We compared demographic, clinical and biological parameters of patients with CPM/EPM with those of age-, sex- and operation date-matched patients without CPM/EPM (controls). RESULTS: Of 1,247 patients, 11 (0.88%) were diagnosed with CPM/EPM based on neuroimaging findings. A higher Model for End-Stage Liver Disease-Na score, preoperative hyponatremia and hypocholesterolemia, as well as greater changes in electrolytes, especially sodium, during surgery, were observed in the CPM/EPM group (p < 0.05). CONCLUSION: CPM/EPM after OLT is more likely to occur in patients with more severe preoperative liver dysfunction and greater changes in electrolyte imbalance, especially sodium, during surgery.

Levofloxacin-associated hypoglycaemia complicated by pontine myelinolysis and quadriplegia.

BACKGROUND: Central pontine myelinolysis (CPM) usually presents in chronic alcoholics and in patients in whom hyponatraemia has been corrected rapidly. However, CPM may occur in other clinical circumstances, including patients with severe hypoglycaemia. We describe the occurrence of CPM and quadriplegia in a patient who experienced fluoroquinolone-associated severe hypoglycaemia. CASE REPORT: A 63-year-old man with Type 2 diabetes mellitus was admitted to hospital for resection of a large liposarcoma. Renal-dose levofloxacin was utilized as part of an antimicrobial regimen to treat post-operative peritonitis. On days 6-8 of levofloxacin therapy, the patient experienced recurrent hypoglycaemia despite total parenteral nutrition, 10% dextrose containing fluids and cessation of insulin therapy 3 days prior to the first hypoglycaemic episode. Hypoglycaemia resolved within 24 h of stopping levofloxacin. After a final and severe hypoglycaemic event, the patient developed quadriplegia and tonic left deviation of gaze. Magnetic resonance imaging revealed a high-intensity lesion in the central pons consistent with CPM. CONCLUSIONS: Fluoroquinolones should be considered as a potential cause of hypoglycaemia. Severe hypoglycaemia has the potential to cause white matter lesions in the pons. Putative mechanisms include failure of membrane ion channels, oligodendrocyte apoptosis and oxidative stress of glucose reperfusion. Fluoroquinolone-associated hypoglycaemia and hypoglycaemia-induced quadriplegia are both rare and we believe this is the first case report linking the two events.

Central pontine myelinolysis in a patient with acute lymphoblastic leukemia after hematopoietic stem cell transplantation: a case report.

We describe a 37-yr-old man who developed central pontine myelinolysis (CPM) after allogeneic hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia. After HSCT, desquamation developed on the whole body accompanied by hyperbilirubinemia. The liver biopsy of the patient indicated graft-versus-host disease- related liver disease, and the dose of methylprednisolone was increased. Then, the patient developed altered mentality with eye ball deviation to the left, for which electroencephalogram and magnetic resonance imaging (MRI) scans were done. Brain MRI scan demonstrated the imaging findings consistent with central pontine myelinolysis and extrapontine myelinolysis. He did not have any hyponatremia episode during hospitalization prior to the MRI scan. To the best of our knowledge, presentation of CPM after allogeneic HSCT is extremely rare in cases where patients have not exhibited any episodes of significant hyponatremia. We report a rare case in which hepatic dysfunction due to graft-versus-host disease has a strong association with CPM after HSCT.

Reversible splenial lesion with restricted diffusion in a wide spectrum of diseases and conditions.

OBJECTIVE: Reversible lesion in the central area of the splenium of the corpus callosum (SCC) is a unique phenomenon occurring particularly in patients with encephalitis or encephalopathy and in patients receiving antiepileptic drugs (AED). We report MR imaging findings, clinical courses, and outcomes in eight patients with various diseases and conditions. MATERIALS AND METHODS: Eight patients with a reversible SCC lesion with transiently restricted diffusion were reviewed retrospectively. Diseases and conditions that were associated with a reversible lesion included epilepsy receiving AED (n=1), seizure from eclampsia receiving AED (n=1), mild infectious encephalitis (n=2), hypernatremia resulting in osmotic myelinolysis (n=1), and neoplasm (n=3) such as acute lymphocytic leukemia, spinal meningeal melanocytoma, and esophageal cancer. We evaluated MR imaging findings and clinical findings. RESULTS: Seven patients had isolated SCC lesions; one patient with osmotic myelinolysis showed additional parenchymal lesions. The reversible SCC lesion shape was oval (n=6) or extended (n=2). The mean apparent diffusion coefficient value of the splenial lesion was 0.40+/-0.16 x 10-3 mm2/s, ranging from 0.22 to 0.64 x 10-3 mm2/s. In a patient with osmotic myelinolysis, additional white matter lesions, shown as restricted diffusion, were revealed as not reversible on follow-up MR imaging. Neurological courses and outcomes were good in seven patients with isolated SCC lesions, but poor in one with osmotic myelinolysis. CONCLUSION: Reversible SCC lesion with restricted diffusion is apparent in a wide spectrum of diseases and conditions. Neurological courses and outcomes are good, particularly in patients with isolated SCC lesions. Knowledge of MR imaging findings and the associated spectrum of diseases and conditions might prevent unnecessary invasive examinations and treatments.

Glucocorticoid replacement in panhypopituitarism complicated by myelinolysis.

OBJECTIVE: To report a case of glucocorticoid substitution in panhypopituitarism that can lead to uncontrolled rise in serum sodium and myelinolysis. CLINICAL PRESENTATION AND INTERVENTION: A 42-year-old man presented with disturbed conscious level and hyponatremia. Initial data suggested glucocorticoid deficiency. Later, hormonal levels indicated panhypopituitarism. MRI of the brain led to the diagnosis of a pituitary macroadenoma. Glucocorticoid substitution was initiated immediately after admission, and possible myelinolysis subsequently became a complication. We report this case to illustrate the fact that glucocorticoid substitution can lead to rapid rise in serum sodium and myelinolysis in panhypopituitarism. CONCLUSION: This case illustrated the need to use minimum doses of glucocortcoids with close monitoring of serum sodium, in order to avoid this complication.

Central pontine myelinolysis complicating treatment of multicentric Castleman's disease and Kaposi's sarcoma in a patient with AIDS.

An HIV positive black African woman presented with widespread lymphadenopathy and pancytopenia that had been ascribed to tuberculosis. Lymph node biopsy showed both Kaposi's sarcoma and multicentric Castleman's disease. Despite antiretroviral therapy and chemotherapy the patient deteriorated, developing confusion and dysphasia. A cranial magnetic resonance scan showed central pontine myelinolysis. Despite supportive therapy the patient died.

EBV associated hemophagocytic syndrome accompanied by central pontine myelinolysis.

The development of central pontine myelinolysis (CPM) has rarely been reported in association with hemophagocytic syndromes (HPS). Here we report a unique case of Epstein-Barr Virus (EBV)-related HPS which was accompanied with CPM. A 72-year-old man who had no significant medical history was admitted to our hospital due to high fever and progressing dysphasia and dysarthria. Physical examination revealed anisocoria of the right pupil, fixed reaction to light, and paralysis of the left vagus nerves. Magnetic resonance imaging revealed low signal intensity on T1-weighted images and high signal intensity T2-weighted images in the patient's central midpontine lesion. Initial work-up showed anemia and thrombocytopenia with elevated levels of serum ferritin, lactate dehydrogenase, and soluble IL-2 receptor. Bone marrow aspiration revealed hemophagocytosis. The EBV genome was detected in the peripheral blood using the polymerase chain reaction method. He was diagnosed as having EBV-related HPS and CPM. Despite intensive treatment with methylpredonisolone, immunoglobulin, and etoposide, he died due to progressive disease and fungal septicemia. The etiology and relation between CPM and HPS are discussed.

[Extrapontine myelinolyses caused by iatrogenic hypernatremia following rupture of a hydatid cyst of the liver with an amnesic syndrome as sequela]. / Mielinólisis extrapontina causada por hipernatremia yatrogénica tras rotura de un quiste hidatídico hepático con síndrome amnésico secuelar.

INTRODUCTION: Extrapontine myelinolisis is a rare condition caused by severe hydroelectrolytic disorders. Following an initial stage of diffuse encephalopathy, the neurological sequelae are usually of diffuse cognitive deficits and extrapyramidal or cortico-bulbo-spinal disorders. We report a case of extrapontine myelinolisis following hypertonic peritoneal lavage due to rupture of a hydatid cyst of the liver (HCL), which was followed by a syndrome of isolated amnesia due to bilateral hippocampal lesions. CLINICAL CASE: Following rupture of a HCL a 37 year old man was treated by peritoneal lavage with hypertonic saline solution. In the immediate postoperative period he had a prolonged confusion state associated with natremia of 176 mg/dl, which was corrected in less than 24 hours. Seven days later the patient had an apathy-inattention frontal syndrome. Six weeks later, and lasting until three months after operation, he had a selective memory deficit in learning tests (of the Barcelona-PIENC series of tests) with normality (29/30) in the MMST. On magnetic resonance there were hyperintense images in T2 in both hippocampus, insulas and corpus callosum. CONCLUSIONS: Generally caused by rapidly corrected hyponatremia, isolated hyponatremia or hypernatremia may also lead to extrapontine myelinolisis. However, we have found no report of extrapontine myelinolisis due to rupture of HCL and treatment with hypertonic peritoneal lavage. The neurological sequelae of extrapontine myelinolisis are usually global cognitive deficits, extra-pyramidal or cortico-bulbo-spinal disorders. Lesions seen on MR are usually found in the basal ganglia, thalamus or corpus callosum (with or without involvement of the pons). We have found no descriptions of bilateral hippocampal lesions causing selective memory deficits in this condition. Treatment by hypertonic peritoneal lavage for ruptured HCL may cause severe hydro-electrolytic alterations which may lead to myelinolisis of the CNS. We report of a case with bilateral hippocampal lesions and selective memory deficit, not previously described within the clinical spectrum of extrapontine myelinolisis.