Therapeutic Plasma Exchange for Treatment-Resistant Tumefactive Demyelinating Lesion: A Case Report.

Tumefactive demyelinating lesions (TDLs) can present as an isolated clinical incidence or could represent the initial presentation of multiple sclerosis. Radiological TDLs are characterized by large tumors like >2 cm space-occupying lesions with mass effect and perilesional edema. Diagnosis is based on MRI imaging and extensive work to exclude other causes and a biopsy of the lesion is often required. First-line treatments include pulsed methylprednisolone. We present a case of a refractory TDL treated successfully with therapeutic plasma exchange.

Susac Syndrome and Role of Therapeutic Plasma Exchange: A Case Report.

Susac syndrome is a relatively uncommon autoimmune disease that predominantly affects young females, with the highest incidence between the third and fourth decade of life, presenting classically with encephalopathy, various CNS dysfunctions, visual impairment due to retinal artery occlusion, and hearing loss. Despite treatment options, such as glucocorticoid steroids, intravenous immunoglobulin, methotrexate, azathioprine, mycophenolate mofetil, or rituximab, some patients with Susac syndrome remain refractory to therapy. We present a case report of a 38-year-old female with refractory Susac syndrome who was treated successfully with plasmapheresis.

Acid-Base Disorders in the Critically Ill Patient.

Acid-base disorders are common in the intensive care unit. By utilizing a systematic approach to their diagnosis, it is easy to identify both simple and mixed disturbances. These disorders are divided into four major categories: metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alkalosis. Metabolic acidosis is subdivided into anion gap and non-gap acidosis. Distinguishing between these is helpful in establishing the cause of the acidosis. Anion gap acidosis, caused by the accumulation of organic anions from sepsis, diabetes, alcohol use, and numerous drugs and toxins, is usually present on admission to the intensive care unit. Lactic acidosis from decreased delivery or utilization of oxygen is associated with increased mortality. This is likely secondary to the disease process, as opposed to the degree of acidemia. Treatment of an anion gap acidosis is aimed at the underlying disease or removal of the toxin. The use of therapy to normalize the pH is controversial. Non-gap acidoses result from disorders of renal tubular H + transport, decreased renal ammonia secretion, gastrointestinal and kidney losses of bicarbonate, dilution of serum bicarbonate from excessive intravenous fluid administration, or addition of hydrochloric acid. Metabolic alkalosis is the most common acid-base disorder found in patients who are critically ill, and most often occurs after admission to the intensive care unit. Its etiology is most often secondary to the aggressive therapeutic interventions used to treat shock, acidemia, volume overload, severe coagulopathy, respiratory failure, and AKI. Treatment consists of volume resuscitation and repletion of potassium deficits. Aggressive lowering of the pH is usually not necessary. Respiratory disorders are caused by either decreased or increased minute ventilation. The use of permissive hypercapnia to prevent barotrauma has become the standard of care. The use of bicarbonate to correct the acidemia is not recommended. In patients at the extreme, the use of extracorporeal therapies to remove CO 2 can be considered.

Excessive elevation of serum phosphate during tumor lysis syndrome: Lessons from a particularly challenging case.

Burkitt's lymphoma is a common cause of tumor lysis syndrome (TLS) and, in the era of aggressive utilization of prophylactic allopurinol and recombinant uricase enzyme, nephrologists are increasingly witnessing monovalent or divalent cation abnormalities without marked uric acid elevation. An 18-year-old male received his 1st cycle of intensive chemotherapy for Burkitt's lymphoma and developed TLS as defined by the Cairo Bishop criteria. Lactate dehydrogenase peaked at 9,105 U/L (range: 130 - 250) and was accompanied by acute kidney injury, including serum creatinine 2.2 mg/dL on the 4th day with oliguria, hyperkalemia, extreme hyperphosphatemia (21.4 mg/dL), hypermagnesemia, and hypocalcemia. Renal replacement therapy decision was made based on life-threatening electrolyte disturbances. The competing necessity to effectively control hyperphosphatemia and avoid the complication of dialysis disequilibrium syndrome prompted us to perform an initial intermittent hemodialysis with simultaneous intravenous mannitol administration, followed by continuous hemodialysis to manage the continued production of phosphorus from cell lysis. Osmotic stability during the therapy session was affirmatively demonstrated (322, 319 mOsm/kg, respectively). The patient showed excellent tolerance for these therapies and eventually recovered renal function as demonstrated during follow-up visits.

Achieving Osmotic Stability in the Context of Critical Illness and Acute Kidney Injury During Continuous Renal Replacement Therapy.

The concept of osmotic stability during renal replacement therapy has received limited attention thus far. We report an illustrative case of a previously healthy 22 year old male presenting after prolonged ventricular fibrillation with 75 minutes of resuscitative efforts before regaining spontaneous perfusing rhythm. Central nervous system protecting hypothermia protocol and veno-arterious (VA) extracorporeal membrane oxygenator (ECMO) therapy were initiated at hospital admission due to refractory hypoxemia. Cardiovascular imaging procedures described global hypokinesis. Due to the combination of anuria, mixed acidosis and hemodynamic instability, we started continuous renal replacement therapy (CRRT) in continuous veno-venous hemodiafiltration functionality with added hypertonic saline solution (HTS) protocol, calculated to stabilize his serum sodium between 148 and 150 mEq/L. Serum osmolality also ranged between 321 and 317 mOsm/kg thereafter. Course was complicated by an acute right leg ischemia distal to VA ECMO cannula placement, requiring salvage therapy with cryoamputation. Vasoactive medication requirement and hemodynamics improved after the addition of intravenous (IV) hydrocortisone. Brain magnetic resonance imaging (MRI) 22 days post-arrest showed signals of limited hypoxic injury. He left the hospital in stable condition with limited neurologic sequelae. Therefore, the use of HTS during CRRT is a viable way to address potential or manifest cerebral edema and reduce the degree of cerebral injury.

Baclofen-induced neurotoxicity in patients with compromised renal function: Review.

Baclofen is a centrally-acting γ-amino butyric acid agonist used mainly in the symptomatic management of spasticity originating from the spinal cord. It is absorbed completely from the gastrointestinal tract, metabolized by the liver to a minor degree, and excreted unchanged by the kidneys. Baclofen is moderately lipophilic and can cross the blood-brain barrier easily. At the usual dosage, it acts mainly at the spinal level without central nervous system (CNS) side effects. During renal failure, however, the elimination of the drug will decrease with a prolonged half-life, resulting in a larger area-under-the-curve exposure and disproportionate CNS toxicity. Clinically, these patients with renal failure may present with a variety of toxic symptoms manifesting at therapeutic/sub-therapeutic doses of baclofen. In cases of unexplained mental status changes in a patient receiving baclofen therapy, a careful assessment of renal function and a high suspicion of baclofen-induced encephalopathy will be key to the diagnosis.
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Prolonged sinus pauses with hydromorphone in the absence of cardiac conduction disease.

A 49-year-old male had open sigmoid colectomy with colorectal anastomosis for sigmoid diverticulitis. The patient was given patient-controlled analgesia (PCA) hydromorphone and subsequently developed bradycardia with prolonged sinus pauses up to 7.1 seconds. The pauses resolved shortly after the hydromorphone was discontinued. This is the first case report to our knowledge of reversible prolonged sinus pauses associated with the use of hydromorphone. Animal studies support a role for opioid signaling at the sinoatrial (SA) node. Hydromorphone is a potential cause of prolonged sinus pauses and should be taken into consideration when monitoring a patient on hydromorphone for pain control.