Argininemia: a treatable genetic cause of progressive spastic diplegia simulating cerebral palsy: case reports and literature review.

Argininemia, a rare autosomal recessive urea cycle disorder, is caused by a deficiency of arginase, with resulting elevated plasma arginine and ammonia levels. Reports to date have focused little on the neurology of this disorder or the efficacy of treatments. A MEDLINE search revealed 25 previously reported cases, to which we have added two brothers who presented with late onset progressive spastic diplegia. Though their degree of enzyme deficiency was comparable, the severity of their phenotypic abnormalities differed substantially. With dietary therapy, both showed improved cognitive and motor function. Late metabolic crises occurred in both, resulting in death of the less severely affected brother. Based on analysis of our clinical database, we report on the full spectrum of neurologic abnormalities seen in argininemia with particular focus on the accompanying progressive spastic diplegia and its response to treatment; progressive decline in head growth; distinctive neuroradiologic findings; and life-threatening later complications. Current and potential future therapies and long-term outcome are summarized.

Brain edema after carotid surgery.

The postoperative hyperperfusion syndrome describes an abrupt increase in blood flow with loss of autoregulation in surgically reperfused brain. Reports described a spectrum of findings, including severe headache, transient ischemia, seizures, and intracerebral hemorrhage. Hypertension is common after carotid artery surgery and often plays a role in the pathophysiology. We now report five patients with severe white matter edema after carotid surgery, a finding not previously included in the hyperperfusion syndrome. Five to 8 days after carotid surgery and after hospital discharge, each patient developed hypertension, headache, hemiparesis, seizures, and aphasia or neglect due to severe white matter edema ipsilateral to the carotid surgery. One patient had a small hemorrhage within the edematous area. Hypertension was severe in four patients and moderate in one. The carotid artery was patent by ultrasound or angiography in each patient after surgery. Transcranial Doppler showed increased velocities ipsilateral to surgery in two patients and bilaterally in one. Computed tomographic abnormalities and neurologic signs resolved within 3 weeks in four of the five patients treated with antihypertensives and anticonvulsants. The fifth patient died from herniation secondary to massive edema. Brain edema with focal neurologic signs should be included as a serious but potentially reversible component of the postoperative hyperperfusion syndrome.

Myositis due to Pleistophora (Microsporidia) in a patient with AIDS.

Microsporidia are obligate intracellular protozoa that parasitize both vertebrates and invertebrates and are now recognized as important pathogens in individuals infected with human immunodeficiency virus type 1 (HIV-1). We describe the clinical and morphological features of a case of pleistophora (microsporidian) myositis in a patient with AIDS and delineate the stages of the microsporidian life cycle, as visualized by light and electron microscopy. We discuss significant aspects of microsporidian infections in humans and of myopathy attributable to other causes in HIV-1-infected individuals. As far as we know, ours is only the second reported case of microsporidian myositis and the first reported case in a patient with documented HIV-1 infection.