Items in AFP with MESH term: Inappropriate ADH Syndrome
Management of Hyponatremia - Article
ABSTRACT: Hyponatremia is an important electrolyte abnormality with the potential for significant morbidity and mortality. Common causes include medications and the syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Hyponatremia can be classified according to the volume status of the patient as hypovolemic, hypervolemic, or euvolemic. Hypervolemic hyponatremia may be caused by congestive heart failure, liver cirrhosis, and renal disease. Differentiating between euvolemia and hypovolemia can be clinically difficult, but a useful investigative aid is measurement of plasma osmolality. Hyponatremia with a high plasma osmolality is caused by hyperglycemia, while a normal plasma osmolality indicates pseudohyponatremia or the post-transurethral prostatic resection syndrome. The urinary sodium concentration helps in diagnosing patients with low plasma osmolality. High urinary sodium concentration in the presence of low plasma osmolality can be caused by renal disorders, endocrine deficiencies, reset osmostat syndrome, SIADH, and medications. Low urinary sodium concentration is caused by severe burns, gastrointestinal losses, and acute water overload. Management includes instituting immediate treatment in patients with acute severe hyponatremia because of the risk of cerebral edema and hyponatremic encephalopathy. In patients with chronic hyponatremia, fluid restriction is the mainstay of treatment, with demeclocycline therapy reserved for use in persistent cases. Rapid correction should be avoided to reduce the risk of central pontine myelinolysis. Loop diuretics are useful in managing edematous hyponatremic states and chronic SIADH. In all instances, identifying the cause of hyponatremia remains an integral part of the treatment plan.
Treatment of Oncologic Emergencies - Article
ABSTRACT: Most oncologic emergencies can be classified as metabolic, hematologic, structural, or side effects from chemotherapy agents. Tumor lysis syndrome is a metabolic emergency that presents as severe electrolyte abnormalities. The condition is treated with allopurinol or urate oxidase to lower uric acid levels. Hypercalcemia of malignancy is treated with aggressive rehydration, furosemide, and intravenous bisphosphonates. Syndrome of inappropriate antidiuretic hormone should be suspected if a patient with cancer presents with normovolemic hyponatremia. This metabolic condition usually is treated with fluid restriction and furosemide. Febrile neutropenia is a hematologic emergency that usually requires inpatient therapy with broad-spectrum antibiotics, although outpatient therapy may be appropriate for low-risk patients. Hyperviscosity syndrome usually is associated with WaldenstrÃ¶m's macroglobulinemia, which is treated with plasmapheresis and chemotherapy. Structural oncologic emergencies are caused by direct compression of nontumor structures or by metastatic disease. Superior vena cava syndrome presents as neck or facial swelling and development of collateral venous circulation. Treatment options include chemotherapy, radiation, and intravenous stenting. Epidural spinal cord compression can be treated with dexamethasone, radiation, or surgery. Malignant pericardial effusion, which often is undiagnosed in cancer patients, can be treated with pericardiocentesis or a pericardial window procedure.