Intracranial dissecting aneurysms in childhood

Children presenting after trauma with headache, seizures, hemiplegia and coma may have an intracranial dissecting aneurysm. Specific angiographic findings provide confirmation of this diagnosis. The dissection occurs subintimally and differs clinically and pathologically from dissecting aneurysms of extracranial arteries. The course in children beyond infancy is catastrophic, justifying consideration of potentially life saving surgical intervention.

Muscle phosphofructokinase deficiency: two cases with unusual polysaccharide accumulation and immunologically active enzyme protein

Two patients with phosphofructokinase (PFK) deficiency had exercise intolerance and increased serum activity of creatine kinase; one presented with hemolytic anemia, hyperuricemia, and gouty arthritis. The glycogen concentration in the muscle of these patients was about twice normal. PFK activity was virtually absent in muscle, but antibodies against the M subunits of the normal human PFK showed cross-reacting material in muscle from both patients. The PFK level in red blood cells, studied in one case, was lower than normal in the patient and both parents. Morphologically, there was extensive deposition of normal glycogen underneath the sarcolemma and in the intermyofibrillar space. In addition, 2% to 3% of the myofibers contained hyaline, PAS-positive, diastase-resistant inclusions that had a filamentous fine structure; histochemical reactions suggested an insoluble form of glycogen. Similar inclusions have not been described previously in PFK deficiency. Accumulation of an abnormal polysaccharide in muscle may be due to a second undiscovered enzymatic defect or may be a metabolic consequence of PFK deficiency.

Disorders of lipid metabolism in muscle

At rest and during sustained exercise, lipids are the main source of energy for muscle. Free fatty acids become available to muscle from plasma free fatty acids and triglycerides, and from intracellular triglycride lipid droplets. Transport of long-chain fatty acyl groups into the mitochondria requires esterification and de-esterification with carnitine by the "twin" enzymes carnitine palmityltransferase (CPT) I and II, bound to the outer and inner faces of the inner mitochondrial membrane. Carnitine deficiency occurs in two clinical syndromes. (1) In the myopathic form, there is weakness; muscle biopsy shows excessive accumulation of lipid droplets; and the carnitine concentration is markedly decreased in muscle but normal in plasma. (2) In the systemic form, there are weakness and recurrent episodes of hepatic encephalopathy; muscle biopsy shows lipid storage; and the carnitine concentration is decreased in muscle, liver, and plasma. The etiology of carnitine deficiency is not known in either the myopathic or the systemic form, but administration of carnitine or corticosteroids has been beneficial in some patients. "Secondary" carnitine deficiency may occur in patients with malnutrition, liver disease, chronic hemodialysis, and, possibly, mitochondrial disorders. CPT deficiency causes recurrent myoglobinuria, usually precipitated by prolonged exercise or fasting. Muscle biopsy may be normal or show varying degrees of lipid storage. Genetic transmission is probably autosomal recessive, but the great male predominance (20/21) remains unexplained. In many cases, lipid storage myopathy is not accompanied by carnitine or CPT deficiency, and the biochemical error remains to be identified.

Rupture of intracranial aneurysm during computerized tomography

A computerized tomographic (CT) scan was performed on a patient with a suspected paraseller mass. Coincident with contrast injection, an unusual and distinctive "starburst" pattern appeared in the right parasellar region and was associated with sudden deterioration in the patient's condition. Subsequent CT and necropsy confirmed a ruptured aneurysm at the suspected site with a large subarachnoid hemorrhage. To our knowledge, this unusual CT picture of a rupturing intracranial aneurysm has not been previously illustrated.

Debrancher deficiency: neuromuscular disorder in 5 adults

Five patients, 4 men and 1 woman, had adult-onset and slowly progressive weakness. There was distal wasting in 2, hepatomegaly in 3, and congestive heart failure in 2. Electromyography showed a mixed pattern with abundant fibrillations. Serum creatine phosphokinase was increased 5- to 45-fold. Blood glucose failed to respond to epinephrine or glucagon, and venous lactate did not rise after ischemic exercise. Muscle biopsy showed vacuolar myopathy affecting both fiber types. By electron microscopy the vacuoles corresponded to large pools of glycogen not limited by a membrane. Glycogen concentration was 3 to 5 times normal in muscle and 7 to 21 times normal in erythrocytes. In the presence of iodine, muscle glycogen showed a spectrum characteristic of phosphorylase-limit-dextrin. Debrancher activity was measured by a spectrophotometric assay and by a radioactive reverse reaction. The activity was lacking in muscle and erythrocytes of 4 patients according to both assays; in 1 patient the reverse reaction was not impaired. Though previously reported in only 5 patients, debrancher deficiency myopathy may not be rare and should be considered in the differential diagnosis of adult-onset hereditary myopathies.

Muscle carnitine deficiency. Genetic heterogeneity

Two types of lipid storage myopathy have been associated with decreased content of carnitine in muscle. In "muscle carnitine deficiency", carnitine concentration is normal in serum, but reduced in muscle. In "systemic carnitine deficiency", apparently due to imparied synthesis of carnitine in the liver, carnitine content is low in both serum and muscle. We studied a woman with a corticosteroid-responsive, probably autosomal recessive, lipid storage myopathy. Carnitine therapy was ineffective and carnitine failed to correct the impaired fatty acid oxidation in muscle homogenates, in contrast to a previous case. Carnitine transport into skeletal muscle was normal. These observations suggest that ll cases of "muscle carnitine deficiency are not the same.

Emery-Dreifuss muscular dystrophy

A man had weakness of humeroperoneal distribution associated with limited range of motion of the cervical spine and elbows. At age 25 he developed permanent atrial paralysis, and a cardiac pacemaker was inserted. Although this case was sporadic, most others have been transmitted as an X-linked recessive trait. Mixed patterns in electromyography and muscle histology have caused nosological confusion, but the unique clinical signs seem to define a distinct form of muscular dystrophy, warranting the designation "emery-Dreifuss" type.

Lipid storage myopathy, ichthyosis, and steatorrhea

A 41-year-old man had ichtyrosis, ectropion, steatorrhea, and slowly progressive proximal limb weakness. Biopsies showed abnormal lipid accumulation in muscle, liver skin, leukocytes, and gastric mucosa. Lipid storage was particularly marked in cultures of skin and muscle, and it increased in subsequent cell generations. By electron microscopy, the lipid globules showed no limiting membranes. The stored lipid was identified by thin-layer chromatography as triglyceride; there was no excess of cholesterol or cholesteryl esters. Muscle carnitine concentration and activities of carnitine palmityltransferase and acid lipase were normal; 14CO2 production from labeled palmitate in leukocytes was not impaired. The excessive accumulation of triglyceride in different tissues and in the progeny of cells in tissue culture suggests a genetic error of lipid metabolism.