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Biomedical subjects

R J Barohn

Publications and source records attributed to R J Barohn.

At least 91 records · Page 5Linked to original sources
PubMed1994

Hyaline body myopathy.

Muscle biopsy from two unrelated patients, a male aged 40 and a female aged 3, with relatively non-progressive limb weakness since infancy, revealed numerous subsarcolemmal glassy, hyaline appearing bodies present in 20-30% of the fibres. Type 1 fibre predominance was present, and the hyaline bodies were exclusive to type 1 fibres. The hyaline bodies were negative with oxidative enzyme and periodic acid-Schiff stains. Electron microscopy showed the hyaline bodies to contain amorphous granular material of unknown composition. No membrane separated the hyaline bodies from the surrounding sarcoplasm. Hyaline body myopathy most likely represents a distinct congenital myopathy because of its childhoot-onset, non-progressive course, and distinct morphological features.

Adult↗
PubMed1994

Bilateral diabetic thigh muscle infarction.

A 19-year-old woman with insulin-dependent diabetes mellitus developed pain and tenderness in the medial aspect of the left thigh and calf, followed 1 week later by similar symptoms in the right leg. Technetium 99m pyrophosphate (PYP) radionuclide scans showed increased flow and uptake in the medial thigh muscles. Magnetic resonance imaging (MRI) of the thigh showed increased signal on proton density and T2-weighted images in the medial and lateral thigh compartments. High-resolution B-mode ultrasound showed hyperechoic changes in the anteromedial thigh muscles, with loss of normal myofascial interfaces, and a mixed appearance, bilaterally. Two months later, after the symptoms had begun to resolve, the images had improved. This case documents bilateral diabetic thigh infarction identified by abnormal technetium 99m PYP flow studies, MRI signal, and B-mode ultrasound imaging.

Adult↗
PubMed1994

The thalamic ataxia syndrome.

We identified 10 patients with contralateral ataxia and hemisensory loss following unilateral thalamic lesions. Seven patients had ischemic infarcts, and three had hemorrhages. Hemiparesis, when present, was only a transient finding, whereas ataxia, dysmetria, dysdiadochokinesia, rebound, and hemisensory loss persisted. Two patients had cerebellar outflow tremor. Another developed a severe Déjerine-Roussy pain syndrome. Four patients had lesions of the dominant hemisphere, and two had visual field deficits. None had mutism, aphasia, or astasia. On radiographic evaluation, all patients had lesions in the mid to posterior thalamus, a localization consistent with a lesion of the dentatorubrothalamic and ascending sensory pathways into the thalamus. The thalamic ataxia syndrome has a distinct localizing value that is distinguishable from the ataxic hemiparesis syndrome. Strokes occurring in the ventral lateral and posterior nuclei of the thalamus produce the clinical picture of contralateral "cerebellar" dysfunction and sensory loss with only transient weakness.

Adult↗
PubMed1994

Sodium channel mutations in acetazolamide-responsive myotonia congenita, paramyotonia congenita, and hyperkalemic periodic paralysis.

Hyperkalemic periodic paralysis (hyperKPP) and paramyotonia congenita (PC) are genetic muscle disorders sharing the common features of myotonia and episodic weakness. In hyperKPP, patient symptoms and signs are worsened by elevated serum potassium, whereas in PC, muscle cooling exacerbates the condition. There are patients in whom features of both hyperKPP and PC are present. These diseases result from molecular alterations in the adult skeletal muscle sodium channel. This report summarizes our sodium channel mutation analysis in 25 families with hyperKPP and PC. We also report the putative disease-causing mutation in acetazolamide-responsive myotonia congenita, a related disease in which myotonia is worsened by potassium but in which episodic weakness does not occur. This missense mutation (I1160V) occurs at a very highly conserved position in the sodium channel, cosegregates with the disease, and was not present in any of a large panel of normal DNAs. Electrophysiologic characterization of specific mutations will lead to better understanding of the biophysics of this voltage-gated ion channel.

Acetazolamide↗
PubMed1994

Inclusion body myositis: treatment with intravenous immunoglobulin.

We report the results of nine patients with inclusion body myositis treated with intravenous immunoglobulin in an open-label uncontrolled study. None of our patients improved on objective manual muscle testing or functional disability scores. One patient developed mild neutropenia, complicating the intravenous immunoglobulin treatment. Our results do not exclude the possibility that intravenous immunoglobulin could be beneficial in some patients by slowing the rate of deterioration or perhaps stabilizing the disease. However, given the lack of objective improvement and high cost of treatment, we would not recommend intravenous immunoglobulin in the treatment of inclusion body myositis unless a blinded, controlled trial demonstrates clear benefit.

Aged↗
PubMed1993

Peripheral nervous system involvement in a large cohort of human immunodeficiency virus-infected individuals.

OBJECTIVE: In individuals who were infected with the human immunodeficiency virus (HIV) we determined the prevalence of peripheral neuropathies (PNs) and explored the relationship between immunologic competence and nerve function. DESIGN: Cohort survey. SETTING: US Air Force medical center. PATIENTS: Population based. Seven hundred ninety-eight of 817 HIV-positive personnel identified by US Air Force HIV screening program from 1985 to 1989. Average age of cohort was 29.2 years. The majority were male with early-stage HIV disease. MAIN OUTCOME MEASURES: Neurologists examined all subjects for symptoms and signs of PN. We grouped patients by CD4 T-lymphocyte count. We further studied 300 HIV-infected volunteers without clinical evidene of PN by nervex

Acquired Immunodeficiency Syndrome↗
PubMed1993

Acute paralytic syndrome in three American men. Comparison with Chinese cases.

OBJECTIVE: To define clinically an unusual acute paralytic syndrome with features distinctive from those of the Guillain-Barré syndrome and similar to those described in Chinese children and young adults. DESIGN: Case series. SETTING: University medical centers. PATIENTS: Three North American men (mean age, 29 years) who presented with acute symmetric weakness and muscle cramps after a preceding gastrointestinal tract illness. These patients had no sensory symptoms, developed no respiratory insufficiency or facial weakness, and had normal to brisk muscle stretch reflexes. RESULTS: Results of serial nerve conduction studies were normal except for low-amplitude motor potentials. Needle electromyography revealed diffuse denervation potentials. Cerebrospinal fluid showed an elevated protein level and, in one case, a mild pleocytosis. A sural nerve biopsy specimen in one patient was normal; muscle biopsy specimens showed denervation atrophy. CONCLUSION: These cases resemble those described in Chinese children and young adults and may represent a postviral monophasic process affecting the anterior horn cell or distal motor nerve terminal. Further pathologic correlation will be required to identify the exact site of the lesion. Differentiation is important when considering modes of treatment.

Action Potentials↗
PubMed1993

Glycogen branching enzyme deficiency in adult polyglucosan body disease.

Branching enzyme activity was assayed in muscle, peripheral nerve, and leukocytes from 2 Ashkenazi-Jewish patients with adult polyglucosan body disease and 1 African-American and 3 Caucasian patients with the same clinical and pathological features. Branching enzyme activity was normal in the muscle specimens from both Jewish and non-Jewish patients. However, the activity was markedly decreased not only in the leukocytes from the 2 Jewish patients (confirming previous findings), but also in peripheral nerve specimens, whereas it was normal in nerve tissue and leukocytes from all non-Jewish patients. These data confirm a branching enzyme deficiency in a subgroup of patients with adult polyglucosan body disease, and show that the defect is tissue-specific, suggesting that adult polyglucosan body disease has more than one biochemical basis.

1,4-alpha-Glucan Branching Enzyme↗
PubMed1993

Sodium channel mutations in paramyotonia congenita and hyperkalemic periodic paralysis.

Clinical and electrophysiological data have outlined a spectrum of similar yet distinct periodic paralyses, including potassium-sensitive (hyperkalemic periodic paralysis [HYPP]) and temperature-sensitive (paramyotonia congenita [PC]) forms. Recent work has revealed that these disorders result from allelic defects in the alpha-subunit of the adult, human skeletal muscle sodium channel. We report an additional mutation, a leucine-->arginine substitution in the S3 segment of domain 4 (L1433R), that results in the PC phenotype. Five other HYPP and PC families have been ascertained, and previously reported sodium channel mutations have been identified in each. Characterization of these mutations and phenotypic variations in such families will contribute to the understanding of sodium channel structure and function relationships, as well as channel malfunction in the periodic paralyses.

Adult↗
PubMed1993

Adult acid maltase deficiency.

A 30-year-old man was referred for neurologic evaluation because of elevated creatine kinase. He had noted symptoms of proximal arm and distal leg weakness for several years, and, on examination, he had weakness in a scapuloperoneal distribution. An electromyogram showed myotonic discharges in the paraspinous muscles, and a muscle biopsy revealed severe vacuolar myopathy. Biochemical analysis of muscle showed acid maltase deficiency. The patient's only brother had childhood-onset acid maltase deficiency and died of respiratory failure at age 27. Acid maltase deficiency may have heterogeneous presentations within a family, and adult AMD can present as a scapuloperoneal neuromuscular syndrome.

Adult↗
PubMed1993

Soluble terminal complement components in human myasthenia gravis.

The loss of membrane acetylcholine receptor (AChR) leading to muscle weakness and impaired neuromuscular junction (NMJ) transmission in human myasthenia gravis (MG) is in part due to complement mediated muscle membrane damage. This has been supported by the histologic finding of C9 at the NMJ in human MG. We evaluated for evidence of terminal complement components in plasma by using an ELISA for SC5b-9 in 42 separate plasma samples from 31 patients with MG and from healthy controls. Abnormal elevations of SC5b-9 was found in 18 of 31 patients (58%) at one or more time points when plotted on a standard positive dilution curve. Multiple samples were available from 8 patients over time. Clinical deterioration in some, but not all, was accompanied by an increase in SC5b-9 values. There was no clear distinction in the group as a whole between MG severity or AChR antibody levels and SC5b-9 values. This supports the potential role of complement-mediated muscle membrane damage in the pathogenesis of human MG, but also demonstrates that plasma levels as measured by ELISA do not always correlate with disease activity.

Adolescent↗
PubMed1993

Kennedy's disease: a clinicopathologic correlation with mutations in the androgen receptor gene.

We confirmed a mutation of the androgen receptor gene as the cause for Kennedy's disease, also called "X-linked recessive spinal and bulbar muscular atrophy" or "bulbospinal neuronopathy." The mutation is characterized by an increased size of a polymorphic tandem CAG repeat within the first exon of the gene. The study population consisted of 17 patients from seven families (five distinct kinships and two isolated cases). Two patients were as yet asymptomatic and had normal examinations. Four carrier females showed the mutant as well as the normal allele; none showed clinical features of Kennedy's disease. There was no large expansion of the mutation observed in three generations of one family. Phenotypic expression between and within families was variable and not related to the size of the mutation. This contrasts with the gene mutations found in myotonic dystrophy and fragile X syndrome, where increased severity of disease correlates with the number of tandem triplet repeats. The findings reported here appear to explain the failure to find genetic anticipation in Kennedy's disease. The DNA test for Kennedy's disease can now be used for definitive diagnosis and carrier detection. In addition, mutation analysis allows early detection, which has implications for potential treatment.

Creatine Kinase↗
PubMed1993

Obturator mononeuropathy caused by pelvic cancer: six cases.

OBJECTIVE: To report the clinical and pelvic CT findings in six patients with obturator mononeuropathy caused by cancer. DESIGN: A clinical case series of six patients followed for 2 months to 10 years (one patient lost to follow-up). SETTING: Three referral centers. PATIENTS: Three men and three women, ages 52 to 81 years. Three patients had transitional cell carcinoma of the bladder, and one patient each had pelvic papillary carcinoma, carcinoma of unknown origin, and lymphoma. MAIN RESULTS: In each patient, symptoms of obturator mononeuropathy were the sole presenting sign of new or recurrent pelvic cancer. Three patients had ipsilateral leg edema in addition to the typical sensory and motor findings of obturator mononeuropathy. Tumor sites detected on pelvic CT that correlated with obturator nerve compression or infiltration, singly or in combination, included the posterolateral wall of the upper pelvis or midpelvis, the anterior wall of the lower pelvis, and the external obturator and pectineus muscles extrinsic to the bony pelvis. Antineoplastic treatment provided symptomatic relief in four patients. CONCLUSIONS: Pelvic CT or MRI should be performed to exclude pelvic tumor in patients with obturator mononeuropathy if there is no temporal association with pelvic trauma or intra-abdominal, pelvic, or hip surgery.

Adenocarcinoma, Papillary↗
PubMed1993

Polyneuropathy complicating bone marrow and solid organ transplantation.

We report a generalized polyneuropathy coincident with the occurrence of graft-versus-host disease in four patients undergoing bone marrow transplantation and accompanying solid organ rejection (heart and kidney) in two patients. The neuropathy affected proximal and distal muscles, demonstrated hyporeflexia or areflexia, and usually had elevated CSF protein. Electrophysiologic studies did not meet strict criteria for demyelination. The signs of neuropathy improved after immunosuppressive treatment or simultaneous to the resolution of graft-versus-host disease or tissue rejection. Polyneuropathy must be considered as a potential complication of tissue transplantation.

Adult↗
PubMed1992

Case-of-the-month: painful thigh mass in a young woman: diabetic muscle infarction.

A 29-year-old female with type I diabetes mellitus developed pain, focal tenderness, and swelling in the posterior left thigh. Subsequent evaluation included a muscle biopsy, which revealed large confluent areas of necrosis and edema, compatible with a diagnosis of diabetic muscle infarction (DMI). Diabetic muscle infarction (DMI) is an unusual neuromuscular complication of diabetes mellitus. DMI begins with the acute onset of focal pain and swelling in the thigh. The anterior compartment (quadriceps muscle group) or posterior compartment (hamstring muscle group) are most frequently involved. The focal region of muscle damage can be noninvasively viewed by magnetic resonance imaging and radionuclide scans. Muscle biopsy demonstrates large confluent regions of muscle necrosis and edema. DMI needs to be differentiated from other processes that can cause leg pain in a diabetic patient.

Adult↗