Edward Arsura

Rhabdomyolysis Related to Cocaine Abuse

Excerpt The rapid escalation in cocaine consumption in recent years has led to the recognition of new toxicities (1). Muscle necrosis caused by cocaine alone or with other factors has rarely been a...

Multifocal atrial tachycardia: Mechanisms, clinical correlates, and treatment

MAT is an uncommon arrhythmia most often seen in elderly patients with chronic pulmonary disease who are critically ill due to acute respiratory or cardiac decompensation. Its importance lies in the fact that it is commonly mistaken for AF, since both disorders are characterized by narrow ventricular complexes, irregular rates, and (depending on the ECG lead observed in MAT) by an apparent lack of P wave activity. This may lead to treatment with digoxin, a drug known to be ineffective in the therapy of MAT, with the potential for producing toxicity in patients who are predisposed. The incidence of MAT in hospitalized patients in various studies ranges from 0.13% to 0.40%. The mechanism of the arrhythmia is thought to be triggered activity arising from increased intracellular calcium stores that may be produced by hypokalemia, hypoxia, acidemia, and increased catecholamines, characteristics commonly found in patients with MAT. COPD, coronary artery disease, CHF, and infection (both pulmonary and nonpulmonary) are the most common clinical settings of MAT. Mortality is very high in all patients studied, ranging from 38% to 62%, and is due to their underlying disease processes and not to the arrhythmia. The need for intubation and mechanically assisted ventilation portends a particularly poor prognosis for survival. Treatment should initially consist of correction of the precipitating causes, as it is common for patients to convert to sinus rhythm both spontaneously and after these measures are taken.(ABSTRACT TRUNCATED AT 250 WORDS)

Metoprolol in the treatment of multifocal atrial tachycardia.

Multifocal atrial tachycardia (MAT) is a difficult arrhythmia to treat. Pharmacologic treatment is generally disappointing, and successful conversion in a predictable manner is uncommon. To assess the efficacy of metoprolol, a relatively selective beta 1-adrenergic blocking agent, we administered this agent to 11 patients (aged 71.8 ± 8.3 yr). All patients had serious pulmonary disease. Hypoxia, hypercarbia, acidosis, and electrolyte abnormalities were corrected before the study. Nine patients were receiving theophylline derivatives and six digoxin. Serum levels for both drugs were in the therapeutic range. Four patients had received verapamil without control of MAT. Mean atrial rate before administration of metoprolol was 142.3 ± 17.2 beat/min and mean ventricular rate was 131.4 ± 24.3 beat/min. One to 3 h after metoprolol (25 or 50 mg orally), all patients were restored to sinus rhythm, with a mean ventricular rate of 86.9 ± 6.8 beat/min (p < .01). Six patients had 3 to 6 premature atrial contractions per minute. No adverse effects were noted, and arterial blood gases before and after therapy were comparable. Five patients expired from their underlying disease and four were continued on metoprolol to maintain sinus rhythm. Metoprolol is effective in the acute and chronic treatment of MAT and may be given to patients with MAT and respiratory failure without serious adverse effects.

Adverse Cardiovascular Effects of Anticholinesterase Medications

Anticholinesterase medications (anti-ChEs) play a significant role in the diagnosis and treatment of myasthenia gravis (MG). The primary effect on the heart produced by a surfeit of ACh is bradyarrhythmias with consequent fall in cardiac output and hypotension; yet, adverse cardiac reactions to these agents have been reported relatively infrequently. The authors describe 12 patients with MG from a pool of more than 1,000 who suffered hypotensive episodes related to use of anti-ChEs. The 12 patients (seven male, five female) had a mean age of 62.6 years; of these, eight adverse reactions occurred after edrophonium, two after neostigmine, and two after pyridostigmine. Seven patients had a recent increase in anti-ChEs and none had a decrease in dosage. Nine patients suffered either from severe sinus bradycardia (20 beats/min), junctional bradycardia, or complete AV dissociation. Two patients had paradoxic sinus tachycardia and all had syncopal or near-syncopal episodes. Evidence for cholinergic stimulation of other organs was generally lacking. No recurrence appeared with reduction of the dose of anti-ChEs or discontinuation of the drug.The authors believe that these agents should be given with caution to patients with inflammatory, infiltrative, or degenerative disease of the conduction systems, patients being treated with digitals, calcium-channel antagonists or beta blockers, patients with myocardial ischemia, and elderly patients. Appropriate resuscitative equipment should be readily available.

Pseudomembranous colitis following prophylactic antibiotic use in primary cesarean section.

A report of a hospital outbreak of pseudomembranous colitis in three patients given prophylactic antibiotic therapy before and after primary cesarean section is presented. All patients shared the same ward and labor and delivery room, and the colitis occurred within an 8-day period. The diagnosis of pseudomembranous colitis was suspected clinically and confirmed by limited colonoscopy and biopsy followed by stool culture and toxin assay for Clostridium difficile. The high carrier rate of Clostridium difficile in the female urogenital tract and altered colonic motility during pregnancy, in addition to antibiotic use, may have contributed to the establishment of this disease. When diarrhea develops postoperatively in patients who have undergone cesarean section, pseudomembranous colitis as a potential serious complication must be kept in mind and necessary precautions taken to impede cross-contamination and development of secondary cases.

Facial diplegia with hyperreflexia-a mild Guillain-Barre Syndrome variant, to treat or not to treat?

Guillain Barre Syndrome (GBS) is readily diagnosed when the presentation is that of ascending weakness and areflexia. Atypical presentations with preserved, and at times, brisk reflexes, can be a diagnostic dilemma. We describe a patient with GBS who presented with facial diplegia and hyperreflexia on examination and discuss management options.

Síndrome de hiperperfusão (pós-operatória) após três semanas da endarterectomia de carótida

Cerebral hyperperfusion syndrome is a recognized complication of carotid endarterectomy. Various studies have documented an incidence of 0.3 to 1.2%. It occurs in the setting of sudden reperfusion of a chronically hypoperfused hemisphere. We present here a case of a 48-year-old lady who developed cerebral hyperperfusion syndrome three weeks after undergoing a carotid endarterectomy for high-grade carotid artery stenosis.Cerebral hyperperfusion syndrome is a recognized complication of carotid endarterectomy. Various studies have documented an incidence of 0.3 to 1.2%. It occurs in the setting of sudden reperfusion of a chronically hypoperfused hemisphere. We present here a case of a 48-year-old lady who developed cerebral hyperperfusion syndrome three weeks after undergoing a carotid endarterectomy for high-grade carotid artery stenosis.

Cysticercosis of temporalis muscle: an unusual cause of temporal headaches. A case report

Cysticercosis is a common parasitic infection caused by encysted larvae of the helminth Taenia solium (pork tapeworm). The central nervous system (CNS) is the most important primary site of infection and the disease can present with solitary or multiple space occupying lesions. Less common presentations in the CNS include the racemose variety with macroscopic groups of cysticerci in the subarachnoid space giving the appearance of a cluster of grapes and basal or ventricular cysticercosis causing obstructive hydrocephalus. Involvement of other organs: skeletal muscle, eyes, myocardium and the lungs has also been reported. Cases of cysticercosis presenting as isolated muscle mass (pseudotumours) without involvement of the CNS have also been recently described in the literature. We present a case of a 43-year-old woman who complained of subacute onset of left temporal pain and headache. Magnetic resonance imaging (MRI) showed characteristic imaging findings suggestive of cysticercosis of the temporalis muscle.

Aripiprazole-induced orthostatic hypotension and cardiac arrhythmia.

PSYCHOTROPIC MEDICATIONS SUCH as tricyclic antidepressants and antipsychotics have been known to cause cardiac conduction disturbances such as sinus nodal abnormalities and bundle branch block. Not much is known about the cardiovascular effects of newer atypical antipsychotics such as aripiprazole (Abilify, Bristol-Myers Squibb, Otsuka Pharmaceuticals, New York, USA). A 46-year-old HIV-positive woman with undetectable viral load and CD4 count >600 per cubic millimeter, presented to her physician with complaints of generalized weakness, fatigue, weight loss and anorexia. In the office she was found to have a heart rate of 170/min and was sent to the emergency room (ER) for further evaluation. In the ER she gave a history of 10–15 episodes of ‘syncope’ per month for the previous 6 months. The episodes were non-exertional, lasting for a few seconds and at times accompanied by palpitations. She had been diagnosed with neurocardiogenic syncope on the basis of a positive tilt-table test. In the ER she complained of palpitations, electrocardiogram showed intermittent supraventricular tachycardia with heart rate in the 150s that responded to vagal maneuvers and diltiazem (Cardizem, Biovail Pharmaceuticals Inc, Bridgewater, NJ, USA) drip. The patient was admitted to the telemetry floor for further evaluation. Echocardiogram did not indicate any significant abnormalities and electrophysiology indicated atrial tachycardia with variable conduction. No ablation was indicated and the patient was continued on diltiazem. The patient had a history of bipolar I disorder and schizophrenia and reported being on aripiprazole 15 mg/day, 8 months prior to the current hospitalization. The patient continued to have acute manic and mixed episodes associated with bipolar I disorder, and aripiprazole was titrated up to 30 mg/day. At the time of hospitalization the patient was not taking any antiretrovirals or other CYP 450 (CYP3A4) enzyme inducers or inhibitors. Medication side-effect was thought to be the most likely cause of the current presentation. Aripiprazole was discontinued and the patient was discharged on oral diltiazem. When last seen at follow up there had been no further episodes of syncope or palpitations. Aripiprazole, a new antipsychotic drug, functions as a partial agonist at the dopamine D2 and the serotonin 5-HT1A receptors and as an antagonist at serotonin 5-HT2A receptor. Although its mechanism of action is still to be fully elucidated its proposed efficacy is thought to be mediated through a combination of the aforementioned effects. Although overall it has a good side-effect profile, it may cause orthostatic hypotension due to its a-1 adrenergic receptor antagonism. In placebo-controlled trials on adult patients, orthostatic hypotension, postural dizziness and syncope were all reported. Fatigue and anorexia have also been reported. Aripiprazole has not generally been associated with cardiovascular effects that characterize other conventional antipsychotics and it has a low incidence of QTc prolongation. Egger et al. reported a case of dosedependent incomplete right bundle-branch block after aripiprazole therapy. When the dose was increased from 15 mg to 30 mg an incomplete right bundle-branch block developed that disappeared on aripiprazole discontinuation. Hence caution should be exercised when initiating aripiprazole therapy in patients with known cardiovascular diseases and in patients with conditions that predispose them to hypotension (dehydration, hypovolemia and treatment with antihypertensive medications).

Central nervous system fungal infections: Observations from a large tertiary hospital in northern India

OBJECTIVEnTo report our observations regarding fungal infections of the brain over two years from a large tertiary hospital in northern India. To identify fungal infections in immunocompetent and immunocompromised patients and to compare the two groups with respect to their age of occurrence, demographic data, clinical profile, radiological findings, response to treatment and outcome.nnnMETHODSnAll consecutive cases of central nervous system (CNS) fungal infections admitted to the hospital over two years were included in this study. The patients were categorized as immunocompetent and immunocompromised, the predisposing factors, symptoms and clinical presentation were studied in detail and the outcomes of the two groups were compared.nnnRESULTSnOf the 50 cases, 25(50%) were that of mucormycosis, 17(34%) were cryptococcosis and 8(16%) cases were that of aspergillosis. 14(28%) cases were immunocompetent and 36(72%) were immunocompromised. The outcome studied was as follows: 28% died of which 4% were HIV positive, 12% were diabetics with severe rhinorbital involvement, 2% had idiopathic thrombocytopenic purpura (ITP), 6% had advanced cancer and 4% had no predisposing illness.nnnCONCLUSIONSnWe observed fungal infections of the brain in both immunocompetent and immunocompromised patients. In immunocompetent patients, early diagnosis and appropriate treatment frequently leads to recovery from the illness. The mortality and morbidity of fungal infections are less in the immunocompetent group of patients.