Biomedical subjects
T E Bertorini
Publications and source records attributed to T E Bertorini.
Paget's disease of bone and motor neuron disease.
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Cervical kyphosis after resolution of myopathic head drop. A case report.
STUDY DESIGN: This is a case report. OBJECTIVES: To present a case of cervical kyphosis after resolution of myopathic head drop. SUMMARY OF BACKGROUND DATA: Myopathic head drop is a severe and persistent local myopathy that never progresses beyond the neck extensor muscles. METHODS: A case is reported of a hospitalized psychiatric patient who experienced the sudden onset of severe neck extensor weakness consistent with myopathic head drop. RESULTS: Although myopathic head drop resolved after 2 years, it left a disabling residual skeletal deformity of the cervical spine. CONCLUSIONS: Myopathic head drop may be a cause of cervical kyphosis.
Solitary focal demyelination in the brain as a paraneoplastic disorder.
Solitary focal demyelination (SFD) in the brain is an uncommon and poorly understood disorder of uncertain etiology that may represent an intermediate entity between multiple sclerosis and acute disseminated encephalomyelitis. In a few reported cases of SFD, the patient was briefly noted to have a nonneurological malignancy. We studied two patients who had solitary focal lesions in the brain. Utilizing magnetic resonance imaging and tissue biopsy, we found the characteristics of the brain lesions in these two patients to be those of SFD. In our combined experience over the past 10 years, we have encountered no similar brain lesions at our medical center. We found it remarkable that both of these patients also had malignancy outside of the nervous system. One had a seminoma, and the other a lymphoma. We conclude that some cases of SFD in the brain may occur as a paraneoplastic disorder associated with nonneurological malignancies.
Complications of intravenous gammaglobulin in neuromuscular and other diseases.
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Assessment of whole body composition with dual energy x-ray absorptiometry in Duchenne muscular dystrophy: correlation of lean body mass with muscle function.
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Multiple mitochondrial DNA deletions in sporadic inclusion body myositis: a study of 56 patients.
Inclusion body myositis, a chronic inflammatory disorder, is the most common cause of myopathy in adults over the age of 50. Diagnosis is based on clinical features and distinctive morphological findings by both light and electron microscopy. The causes of inclusion body myositis are still unknown. Ultrastructural mitochondrial changes and ragged-red fibers are common in patients with sporadic inclusion body myositis, and multiple [correction of mutiple] mitochondrial DNA (mtDNA) deletions have been reported in 3 such patients, suggesting that mtDNA mutations may have a pathogenetic role. We studied 56 patients with sporadic inclusion body myositis, using a combination of clinical, morphological, biochemical, and molecular genetic analyses to determine the frequency and the distribution of mtDNA deletions. Using the polymerase chain reaction, we found multiple mtDNA deletions in 73% of patients, compared to 40% of normal age-matched control subjects and 47% of disease control subjects. The presence of deletions correlated with morphological evidence of ragged-red, cytochrome c oxidase-negative fibers, and with defects of complexes I and IV of the electron transport chain. Although aging may account for a proportion of mtDNA deletions in patients with sporadic inclusion body myositis and control subjects, mtDNA alterations may be accelerated in sporadic inclusion body myositis.
Choroid plexus histoplasmoma: clinical, pathologic, and imaging findings.
Histoplasmosis of the choroid plexus has not previously been described. We report its occurrence, as well as its clinical, pathologic, and imaging characteristics in one case. Clinically, our patient's choroid plexus lesion produced encephalopathy and third nerve palsy. On imaging it appeared as a hemorrhage or calcification. Cerebrospinal fluid studies were consistent with a chronic meningeal process uncomplicated by hemorrhage. Stereotactic biopsy of the choroid plexus was required to establish the diagnosis of cerebral histoplasmosis. Pathologic examination also revealed prominent abnormal calcification, which permitted the lesion of masquerade as a hemorrhage on computed tomographic and magnetic resonance images.
Octreotide enhances positive calcium balance in Duchenne muscular dystrophy.
Although receptors for somatostatin are found in bone cells, the effect of somatostatin analogs on calcium metabolism is unknown. The authors studied, in a metabolic ward, the effect of octreotide (a long-acting somatostatin analog) and a placebo in two 6-day calcium balance periods in 8 children with Duchenne muscular dystrophy. As expected, octreotide (2 micrograms/kg, subcutaneously, every 8 hours) reduced serum growth hormone and somatomedin (IGF-1) to levels found in growth hormone deficiency. Octreotide enhanced calcium retention by 30% (96 mg daily [P < 0.04]) in 7 boys for whom complete data (diet, urine, and fecal calcium) were available. In 6 children with urinary calcium excretion (Uca) greater than 50 mg daily, octreotide markedly lowered Uca, from 114 +/- 23 mg daily to 61 +/- 9 mg daily (P < 0.03). Calcium retention occurred in patients with or without initial hypercalciuria, but the higher the basal Uca, the greater was the inhibition by octreotide (r = 0.79; P < 0.03). Inactive, nonambulatory patients had a more pronounced response of Uca to octreotide (P < 0.02). Octreotide caused a mild, nonsignificant reduction in fecal calcium, with no major changes in serum calcium, phosphorus, parathyroid hormone, urinary excretion of sodium and potassium, or in creatinine clearance. Based on the current observations and the presence of receptors for somatostatin in bone cells, this hormone may have, at least on a short-term basis, an anabolic effect on calcium, perhaps favoring its deposition in bone.
False evidence of carotid stenosis on magnetic resonance angiography caused by surgical clips.
Patients with transient ischemic attacks are increasingly studied with magnetic resonance angiography, allowing noninvasive evaluation of both the intracranial and the extracranial vessels. Described here are 3 patients who after endarterectomies presented with transient ischemic attacks and in whom magnetic resonance angiography with a two-dimensional time-of-flight pulse sequence showed a false-positive arterial stenosis, as documented by transfemoral carotid angiography. The pseudostenosis was believed to be artifactually caused by operative clips. Results of magnetic resonance angiography should be interpreted with caution in patients with previous neck surgery.
Cardiac arrest following vertebrobasilar stroke.
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Single-fiber electromyography in neuromuscular disorders: correlation of muscle histochemistry, single-fiber electromyography, and clinical findings.
We performed single-fiber electromyography (SFEMG) and correlated the results with muscle-biopsy histochemistry in 56 patients with various neuromuscular diseases. Increased muscle-fiber density, delineated by SFEMG, was most prominent in diseases of ordinary denervation, namely motor neuron disorders and peripheral neuropathies, and it correlated with histochemical fiber type grouping. Both phenomena reflect denervation followed by reinnervation. In patients with central core disease and rod disease, fiber density was not increased despite massive type I fiber predominance. The normal distribution of type I fiber subtypes in those patients indicated tht their fiber predominance was not due to sprouting and reinnervation, but probably to paucity of the type II fibers. In type I fiber hypotrophy with central nuclei, fiber density was increased, perhaps attributable to the small diameter and consequent denser packing of the type I fibers. Fiber density was slightly increased in the majority of patients with acid-maltase deficiency, limb-girdle dystrophy, and polymyositis, in nearly half with mitochondrial myopathy, and in 1 older Duchenne dystrophy patient. In these myopathic disorders, myogenous deinnervation (followed by reinnervation) is one possible explanation. Normal fiber density was present in all patients with muscle phosphorylase deficiency, myotonia congenita, and in the hypokalemic periodic paralysis patients under age 40.
Eccentric and concentric muscle performance in patients with spastic paresis secondary to motor neuron disease. A preliminary report.
This study investigated the potential value of eccentric (ECC) and concentric (CONC) isokinetic testing for quantifying motor deficit in patients with spastic paresis secondary to motor neuron disease. We hypothesized that, at a moderately fast (120 degrees s-1) angular velocity, spastic patients would demonstrate different ECC-CONC torque relationships from healthy controls or patients with non-spastic neuromuscular disorders. Eleven patients with motor neuron disease having clinical evidence of spasticity, and 11 disease-control patients (with non-spastic disorders, e.g. lower motor neuron disease or myopathy) underwent isokinetic testing. One healthy subject was matched to each of the 22 patients. The average torque generated during maximal voluntary ECC and CONC knee flexion (KF) and extension (KE) was measured using an isokinetic dynamometer (Kin-Com). Reliability was established (all ICC > or = 0.97) for patient torque measurements. Relative strength (% of control subject torque) in spastic patients was significantly higher for ECC than for CONC actions in both KF and KE; conversely, in non-spastic disease-control patients relative strength was not affected by the type of muscle action. The ECC/CONC average torque ratios for KE and KF at 120 degrees s-1 were significantly greater in spastic patients than controls, but did not differ from controls in non-spastic patients. In spastic patients the ECC-CONC imbalances were related to ambulatory dysfunction. In four spastic patients followed with serial testing, the disproportion between ECC and CONC voluntary capacity persisted over time.(ABSTRACT TRUNCATED AT 250 WORDS)
Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): clinical, biochemical, and genetic features of an autosomal recessive mitochondrial disorder.
We studied the clinical, biochemical, and genetic features of eight patients with the autosomal recessive mitochondrial syndrome mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). MNGIE is clinically characterized by ophthalmoparesis, peripheral neuropathy, leukoencephalopathy, gastrointestinal symptoms (recurrent nausea, vomiting, or diarrhea) with intestinal dysmotility, and histologically abnormal mitochondria in muscle. Brain MRI scans were consistent with leukodystrophy in seven patients examined. Nerve conduction and EMG studies were compatible with a sensorimotor neuropathy; quantitative EMG of two patients suggested a myogenic process. Muscle mitochondrial enzyme analysis revealed a partial defect of cytochrome c oxidase activity in five patients; three had additional respiratory chain enzyme defects. Two patients had isolated complex I defects, and one had normal respiratory chain function. Southern blot analysis revealed multiple deletions of mitochondrial DNA in four of eight patients.
Respiratory insufficiency in adult-type acid maltase deficiency.
AMD is a glycogen storage disease that affects all age groups. In both childhood and adult forms, the classic clinical picture is that of a progressive myopathy that may resemble polymyositis or limb girdle muscular dystrophy. Respiratory muscle involvement is common, may occur early in the course of the disease, and is the most frequent cause of mortality from AMD. These findings underscore the need to consider AMD in the differential diagnosis of unexplained respiratory insufficiency. We have described the case of one patient in whom respiratory failure was the initial symptom and two other cases in which the patient had progressive muscular weakness and subsequent respiratory failure. A review of the literature revealed that respiratory muscle weakness has been reported in 21 of 43 cases of AMD in adults. In 10 cases respiratory insufficiency was preceded by only mild or moderate weakness.
Eccentric muscle performance of elbow and knee muscle groups in untrained men and women.
Maximal voluntary eccentric (ECC) and concentric (CON) capacity of knee and elbow muscle groups was investigated in healthy untrained men (N = 40) and women (N = 50), 21-67 yr of age. Purposes of the study were to describe torque-velocity and ECC-CON relationships, and to compare these relationships among muscle groups and between genders. Average torque was measured at angular velocities of 30 degrees and 120 degrees.s-1 from knee flexor (KF), knee extensor (KE), and elbow flexor (EF) muscle groups unilaterally, using an isokinetic protocol including gravity compensation. Data were analyzed using ANOVA procedures, and a significance level of 0.01 was used for all hypothesis testing. Torque-velocity relationships were similar for each muscle group and gender; i.e., ECC average torque did not change as a function of velocity and CONC torque decreased as angular velocity increased. Women generated greater ECC relative to CONC torque than men in upper and lower extremity muscle groups. Muscle groups differed in ECC relative to CONC capacity in both men and women, with ECC/CONC ratios being greater for KE and EF than KF. In all muscle groups, the magnitude of ECC-CONC differences increased as angular velocity increased. Genders differed in relative strength balance between muscle groups, with men exhibiting greater KF/KE and EF/KF torque ratios than women for both ECC and CONC actions. Results of this study contribute to the body of women.(ABSTRACT TRUNCATED AT 250 WORDS)
Congenital muscular dystrophy presenting with respiratory failure.
Respiratory failure is an unusual initial manifestation of congenital muscular dystrophy. The authors describe a case of congenital muscular dystrophy in a patient presenting with rhabdomyolysis at birth. Despite an initially poor prognosis, aggressive respiratory therapy during the neonatal period permitted normal subsequent development. The muscular dystrophy predominantly involved the respiratory muscles.