Bilateral mental nerve neuropathy in an adolescent during sickle cell crises

Mental nerve neuropathy causes the "numb chin" syndrome and is usually associated with mandibular bone injury or disease in adults. It has been reported in adults during sickle cell crises. We describe a 15-year-old boy who developed bilateral mental nerve neuropathies during a sickle cell crisis. This case is unusual because of the simultaneous bilateral involvement and because of the age.

Metabolic disorders causing childhood ataxia

Ataxia is a common neurologic finding in many disease processes of the nervous system, and has classically been associated with numerous metabolic disorders. An error of metabolism should be considered when the ataxia is either intermittent or progressive. Acute exacerbation or worsening after high protein ingestion, concurrent febrile illness, or other physical stress is also suggestive. A positive family history can be an important diagnostic clue. Progressive molecular and biochemical techniques are revolutionizing this area of medicine, and there has been rapid advancement in understanding of the disease processes.

Tick paralysis in children: electrophysiology and possibility of misdiagnosis

The authors report six patients with tick paralysis seen over 5 years. Clinical and electrodiagnostic findings failed to adequately distinguish tick paralysis from Guillain-Barré syndrome in these patients. Finding a tick attached to the scalp or the nape of the neck and removing it resulted in rapid clinical improvement.

Cytokine induction in fetal rat brains and brain injury in neonatal rats after maternal lipopolysaccharide administration

Induction of proinflammatory cytokines has been proposed to be a link between prenatal maternal intrauterine infection and neonatal brain damage. It is known that the endotoxin, lipopolysaccharide (LPS), released during bacterial infection crosses the placenta. Cytokine induction in the fetal rat brain after maternal administration of LPS was determined by reverse transcriptase-polymerase chain reaction method. LPS suspension in pyrogen-free saline was administered (i.p.) to pregnant rats at 18 d of gestation. The control group was treated with pyrogen-free saline. Expression of the proinflammatory cytokines, tumor necrosis factor-alpha and IL-1beta mRNA, in the fetal rat brain was increased in a dose-dependent manner at 1 h after LPS administration. The great increase in expression of IL-1beta mRNA was only observed at 1 h after injection of LPS (4 mg/kg), whereas the increased expression of tumor necrosis factor-alpha was still detectable from 4 to 24 h after LPS administration. Brain injuries were examined by immunohistochemistry in 8-d-old rat pups born to the dams that were consecutively treated with LPS (500 microg/kg) or pyrogen-free saline on gestation d 18 and 19. No apparent necrotic tissue damage was found in either the LPS group or the control group. Myelin basic protein staining, as a marker of myelin, was clearly observed in the internal capsule and the fimbria hippocampus in the rat brain from the control group. Myelin basic protein staining was much less and weaker in the brains of the LPS-treated group. Glial fibrillary acidic protein-positive astrocytes were observed in both the control and the LPS-treated groups. The LPS-treated group appeared to have more glial fibrillary acidic protein-positive astrocytes in the hippocampal and the cortex areas of the brain than the control group. Immunoblotting data showed that glial fibrillary acidic protein content in the cortex or the hippocampus of the LPS-treated rat brain was higher than in the control group. OX-42-positive staining (a marker of the type 3 complement receptors) of microglial cells was greatly reduced in the 8-d-old rat brain after maternal LPS administration. However, histochemistry with tomato lectin showed that staining of both amoeboid and ramified microglial cells in the LPS-treated rat brain was similar to that in the control group. The overall results indicate that maternal LPS administration induces an increased expression of IL-1beta and tumor necrosis factor-alpha mRNA in the fetal brain. Maternal LPS administration also increases glial fibrillary acidic protein-positive astrocytes, decreases myelin basic protein and alters immunoreactivity of microglia in the brain of offspring. Although results from the current study do not provide direct evidence linking LPS-induced cytokines with the abnormalities in the neonatal rat brain, our animal model may be appropriate for exploring the mechanisms involved in the effects of maternal infection on glial cells in the brains of offspring.

Lethal neonatal autosomal recessive axonal sensorimotor polyneuropathy

Peripheral neuropathy is an uncommon cause of generalized hypotonia and weakness in infancy. It occurs as a part of the clinical syndrome in some neurodegenerative disorders of infancy, but seldom causes respiratory failure or swallowing difficulties. We report a lethal autosomal recessive axonal polyneuropathy with neonatal onset in a large kindred from Northern Mississippi. One patient was studied in detail at our medical center and the information on 12 other affected infants in this large family were gathered from medical records and by interviewing the family members. Patients were symptomatic for the polyneuropathy before birth and died in the first year of life from respiratory complications. Thirteen babies were affected by this clinical phenotype in four generations of this family with a high frequency of consanguinity. Affected babies were of both sexes and were born to healthy consanguineous parents. The clinical phenotype of polyneuropathy in our index patient and other affected babies in this family was similar, and represents a unique form of hereditary neonatal polyneuropathy.

Guillain-Barré syndrome

GBS is an acquired, monophasic illness of the peripheral nervous system that usually presents with a gait disturbance and clinical features of pain, weakness, and areflexia. The etiology of the disease is immune-mediated and directed against the peripheral nervous system myelin, axon, or both. A careful history, physical examination, and routine laboratory tests are necessary to make a clinical diagnosis and to exclude other disorders that cause acute weakness. Laboratory tests that support the diagnosis, such as an increased CSF protein and abnormal electrodiagnostic studies, may be normal early in the illness. The most serious complications during the acute phase of the disease are respiratory failure and autonomic disturbances. Plasma exchange or IVIG shortens the duration and severity of the disease significantly. The prognosis for children who have GBS generally is excellent for full and functional recovery, using modern intensive care for respiratory support and the management of other complications.

Muscle rigidity due to fentanyl infusion in the pediatric patient

Two cases of fentanyl-induced muscle rigidity are presented. Significant features of these cases include the unusual pattern of rigidity and the use of fentanyl doses lower than those usually associated with muscle rigidity.

Intervertebral disk calcification: an unusual cause of acquired torticollis in childhood

Intervertebral disk calcification in children can result in a syndrome of neck pain, muscle spasm, and torticollis. Usually the clinical course is benign with spontaneous recovery; however, occasionally nerve root or spinal cord compression can be seen. We report a seven-year-old patient with symptomatic cervical disk calcification and briefly discuss the salient clinical and radiographic features.

Treatment of childhood dermatomyositis with high dose intravenous immunoglobulin

Two children with chronic dermatomyositis who were treated with intravenous immunoglobulin (IVIG) for 28 and 12 months, respectively, are reported. Both patients had received prednisone and immunosuppressive agents prior to IVIG treatments and had experienced significant side effects. Strength and functional abilities improved in both patients in a gradual stepwise fashion with IVIG treatment. One patient achieved remission and continues to do well without any immunosuppressive agents; in the other patient, the dose of oral steroids was reduced and other immunosuppressive agents were discontinued. Use of IVIG was associated with headaches, nausea, and vomiting in both patients. IVIG was an useful adjuvant therapy in these 2 children with dermatomyositis without any significant side effects.

Rapid-fractionation pre-operative chemoradiation for malignant periampullary neoplasms

The multimodality treatment of adenocarcinoma of the pancreatic head has been shown to improve survival compared with surgery alone. The delivery of chemotherapy and radiation therapy (chemoradiation) before rather than after pancreaticoduodenectomy ensures that all patients who undergo surgery receive the other components of multimodality therapy. In an effort to reduce overall treatment time and cost, the use of rapid-fractionation preoperative chemoradiation was explored. Radiation therapy was delivered with 18-MeV photons to a total dose of 30 Gy given in 10 fractions over 2 weeks. 5-Fluorouracil was given concurrently by continuous infusion at a dose of 300 mg m-2 day-1. Four weeks after the completion of chemoradiation, patients underwent pancreaticoduodenectomy and electron-beam intraoperative radiation therapy (10 Gy). All patients completed the treatment programme without delay. The rapid-fractionation programme was delivered at nearly half the cost of standard chemoradiation and histologic evidence of tumour cell injury was present in all resected specimens. There were no perioperative anastomotic complications, and median hospital stay was 20 days. Rapid-fractionation chemoradiation warrants further study in the neoadjuvant setting.

Vogt-Koyanagi-Harada syndrome in a 4-year-old child

Vogt-Koyanagi-Harada syndrome is an acquired illness with ocular, cutaneous, and/or neurologic features. A 4-year-old child who acutely developed visual disturbances and headache and was found to have serous retinal detachments and aseptic meningitis is presented. Improvement was rapid with corticosteroid therapy. This is the youngest reported patient with Vogt-Koyanagi-Harada syndrome.

Fat embolism syndrome in a child with muscular dystrophy

Fat embolism syndrome is a relatively common complication of orthopedic trauma. Once thought to be rare in children, it probably occurs with a similar frequency as in adults, but is often subclinical. Clinically apparent fat embolism syndrome may exhibit neurologic, pulmonary, and cutaneous manifestations. It often resolves without sequelae if it is recognized promptly and supportive treatment is provided. We present a pediatric case of fat embolism syndrome and review the literature on its diagnosis and management in children.

Prematurity and early-onset juvenile myasthenia gravis

A child manifested ocular myasthenia gravis at age 16 months which progressed to bulbar and mild systemic weakness over a 3-year period. The medical history was significant for premature birth at 32 weeks gestation and birth weight 940 gm. A review of reported patients with juvenile myasthenia gravis with adequate documentation of the birth history, noncongenital onset, typical clinical course and diagnostic findings, and elevated titers of antiacetylcholine receptor antibodies revealed that 55% with onset before age 3 years had a history of prematurity. This association of myasthenia gravis and prematurity may provide insights to the pathogenesis of the disease.

Local anesthetic mortality: report of case

The case of a healthy five-year-old, thirty-six pound female patient scheduled for multiple extractions is reported. The child received a total dose of 270 mg of mepivacaine, instead of the correct dose of 72 mg, which resulted in multiple seizures, hospital admission, pneumonia, and death caused by anoxic brain injury secondary to cardiopulmonary arrest following the overdose.

MK-801 does not protect against hypoxic-ischemic brain injury in piglets

BACKGROUND AND PURPOSE

The excitatory amino acid inhibitor MK-801 has been shown in many animals species to protect against hypoxic-ischemic brain injury. We sought to determine whether hypoxic-ischemic injury to the newborn pig's brain could be prevented by the use of MK-801.

METHODS

Hypoxic-ischemic injury to the brain was induced in forty 0-3-day-old piglets. They were randomized to receive either 3 mg/kg MK-801 (MK-801 group, n = 20) or vehicle (control group, n = 19) prior to insult. At time 0, the carotid arteries were ligated and the blood pressure was reduced by one third by hemorrhage. At 15 minutes, inspired oxygen was reduced from 50% to 6%. At 30 minutes, inspired oxygen was changed to 100%, carotid ligatures were released, and the withdrawn blood was reinfused. An additional 14 piglets received 3 mg/kg MK-801 but not hypoxic-ischemic injury (drug-only group), and a final group of 11 piglets were subjected to only a sham operation (sham group).

RESULTS

Neurological examination scores at 24, 48, and 72 hours showed that MK-801 and drug-only piglets were significantly worse than the controls. Pathological examination of the brains at 72 hours showed significantly greater damage in the brains of the MK-801 and control pigs relative to the sham and drug-only groups. No differences were found between the control and the MK-801 groups. No differences were found between the sham and drug-only groups.

CONCLUSIONS

MK-801, at a dose of 3 mg/kg, causes neurological dysfunction in piglets lasting at least 72 hours, but neither causes brain damage nor ameliorates the effects of hypoxic-ischemic injury to the brain of the newborn pig.

Fructose-1,6-diphosphate, when given five minutes after injury, does not ameliorate hypoxic ischemic injury to the central nervous system in the newborn pig

Hypoxic ischemic injury to the brain was induced in 12 0- to 3-day-old piglets. At time 0, the carotid arteries were ligated, and the blood pressure was reduced by one third by hemorrhage. At 15 min, inspired FIO2 was reduced from 50 to 6%. After 10 min of flat EEG, the FIO2 was changes to 100%, the carotid ligations were released, and the withdrawn blood was reinfused. Five minutes after reoxygenation, the piglets were randomly assigned to either receive 350 mg of fructose-1,6-diphosphate over 5 min, followed by 6 mg/kg/min for the ensuing 50 min, or an equivalent volume of normal saline. 3 days after the experiment, the animals received a neurologic examination by a blinded observer, were then sacrificed, and the brains examined by a blinded observer. There were no significant differences in the degree of damage between the two groups.

Mistaken diagnoses in continuous muscle fiber activity of peripheral nerve origin

The syndrome of continuous muscle fiber activity of peripheral nerve origin has manifestations that resemble those of many other more common neurologic disorders during childhood and infancy. This similarity often leads to misdiagnosis when an adequate index of suspicion is not entertained and a comprehensive electromyographic examination is not performed. Two affected patients from 1 family are reported to illustrate the type of diagnostic errors that were made before the establishment of the correct diagnosis.

Hematologic monitoring in children with epilepsy treated with carbamazepine

One hundred seventy-six children treated with carbamazepine for epilepsy were monitored over a 12-month period to determine the effects of carbamazepine on the hematologic system. There were no significant changes within the total population in the mean hematocrit or platelet count. The white blood cell count and total neutrophil count showed declines at 1, 8, and 12 months, but the differences did not achieve statistical significance. There was no correlation between the hematologic parameters and carbamazepine blood level, age or sex, or the presence of other drugs. Pretreatment leukopenia and neutropenia were present in 2.8% and 4.0% of children, respectively. During carbamazepine therapy, 8.0% and 17.0% of the children developed leukopenia and neutropenia, respectively, and it was persistent in 1.7% and 2.8%, respectively. The changes in the white blood cell count could be attributed to the changes in the total neutrophil count.

Intracranial aneurysms in a child with recurrent atrial myxoma

Subarachnoid hemorrhage and formation of intracranial aneurysms occurred in an adolescent with recurrent atrial myxomas without a history of cerebral embolic infarction. Myxomatous intracranial aneurysm is a potentially lethal complication in children.

Intervertebral disc calcification in children

Calcification of cervical intervertebral discs in children is due to an uncommon, but distinct, disease of unknown etiology. Signs and symptoms of nerve root or spinal cord compression are unusual and acute symptoms are followed by a benign course and spontaneous recovery. We describe a 5-year-old patient with symptomatic cervical disc calcification and discuss the relevant clinical and radiographic features.

Delayed intracerebral hematoma at the site of a subarachnoid bolt pressure monitor. Case report

The authors report development of a delayed intracerebral hematoma following use of a subarachnoid bolt for intracranial pressure monitoring. This complication has not been previously reported.

Insulin binding in denervated muscle

Insulin binding was measured in rat muscle following denervation. There was a 40% reduction in the number of high-affinity insulin receptors, with no change in the insulin binding Kd. Selected muscles showed a 40%-60% reduction in weight during this period. The down-regulation in the number of insulin receptors may contribute to the mechanism of muscle atrophy following denervation.

Lactic acidosis in childhood: Part II

Lactic acidosis is associated with both inherited and acquired metabolic diseases. Lactic acid metabolism in the presence of altered gluconeogenesis, anaerobic glycolysis, and acid-base balance is a major factor in many disorders. Lactic acid can be formed only from pyruvic acid; therefore, disorders that increase pyruvate concentration, enhance lactic acid formation, or reduce lactic acid degradation cause lactic acidosis. Inborn metabolic errors that are accompanied by derangement of metabolic pathways of glucose, pyruvate, amino acids, and organic acids as well as toxic and systemic conditions that promote tissue hypoxia or mitochondrial injury result in lactic acidosis. In the presence of acquired disorders, treatment is directed initially toward modification or cure of the primary condition and then toward eliminating acidosis and other metabolic complications. Specific therapy is available for some inborn errors of metabolism.

Lactic acidosis in childhood: Part I

Lactic acidosis accompanies many acquired and inherited metabolic diseases. The role of lactic acid in anaerobic glycolysis, gluconeogenesis, and acid-base balance is key to the understanding of these disorders. Because lactic acid can be formed only from pyruvic acid, disorders which increase pyruvate production, inhibit its catabolism, or shift the equilibrium toward lactic acid formation cause lactic acidosis. Lactic acidosis results from systemic diseases and toxins which produce tissue hypoxia or mitochondrial injury. Abnormalities of other metabolites such as glucose, pyruvate, amino acids, and organic acids may provide clues to inborn metabolic errors. Treatment must first be directed toward removing precipitating causes of the acquired disorders and then toward correcting the acidosis and other metabolic complications such as hypoglycemia. Some of the inborn errors respond to specific therapies.

Ischemia of the brain stem as a cause of sudden infant death syndrome

Recent evidence indicates that the sudden infant death syndrome (SIDS) is related to abnormal control of respiration. Focal morphologic changes have not been noted. In a case of SIDS, ischemic degeneration was noted bilaterally in the medulla, particularly in the dorsal motor nucleus of the vagus nerve. Pathologic changes were not found elsewhere in the CNS. To our knowledge, this is the first description of a focal brain-stem lesion in SIDS that had enough of a role in altered respiratory control to cause death.

Glycogen-membrane complexes in denervated human skeletal muscle

We describe an unusual intracellular complex of glycogen with smooth, cisternal, cytoplasmic membranes (glycogen-membrane complexes, GMC) in denervated human skeletal muscle. Glycogen particles were always intimately associated with these structures, although the staining intensity varied markedly with different fixation conditions. This may account for previous investigations of similar structures in which an association with glycogen was not recognized. Electron micrographs of tannic acid-enhanced specimens, and of freeze-fracture replicas, showed similarities between the GMCs and the terminal cisternae of the sarcoplasmic reticulum: (i) GMCs resembled the terminal cisternae of the sarcoplasmic reticulum in the size and asymmetric distribution of intramembranous particles seen in freeze-fracture replicas; (ii) tannic acid-enhanced thin sections of GMCs showed intense staining of the cisternal contents and irregular staining of the cytoplasmic leaflet, similar to the appearance of the sarcoplasmic reticulum terminal cisternae; and (iii) triad-like junctions were seen between the glycogen-membrane complexes and elements of the transverse tubule system.

Muscle pyruvate oxidation following denervation and reinnervation

Muscle pyruvate metabolism was studied in rats following sciatic nerve crush. Control studies showed high pyruvate dehydrogenase and lipoamide dehydrogenase enzyme activity in muscle with type 1 fiber predominance (soleus) and low activities in muscle with type 2 fiber predominance (extensor digitorum longus), whereas lactate dehydrogenase was much higher in the latter. Following denervation, both muscles showed a significant reduction in pyruvate dehydrogenase enzyme activity. During reinnervation, muscle with type 2 predominance developed significantly elevated pyruvate oxidation enzyme activities.

Effects of dichloroacetate on brain tissue pyruvate dehydrogenase

The activation of the pyruvate dehydrogenase complex (PDHC) by dichloroacetate (DCA) was studied in brain tissue. Chronic administration of DCA to rats caused no significant change of PDHC activation in brain. DCA brain concentrations were comparable to those of other tissues in which activation is known to occur. No effect of DCA on PDHC could be demonstrated from isolated brain mitochondria, whereas DCA reversed the deactivation of PDHC by ATP, alpha-ketoglutarate plus malate, and succinate in liver mitochondria. This study suggests that the regulation of PDHC activation in neural tissue differs from that in other tissues.

Human muscle pyruvate dehydrogenase activity

Muscle pyruvate dehydrogenase complex (PDHC) activity was studied in 70 patients with different neuromuscular disorders. Children had higher total PDHC and lipoamide dehydrogenase (LAD) activities than adults. There were no significant differences in muscle PDHC activity in patients with Friedreich ataxia, patients with other ataxias, or age-matched controls. Kinetic analysis of LAD showed no differences in Km for lipoamide between Friedreich ataxia patients and controls.

Improvement of muscle function in acid maltase deficiency by high-protein therapy

Progressive muscle weakness in acid maltase deficiency (AMD) is associated with intralysosomal accumulation of glycogen and altered myofibrillar morphology. A rapid fall in circulating branched chain amino acids after protein ingestion in a child with AMD suggested that increased net muscle protein catabolism may play a part in the pathogenesis of this condition. To reduce this muscle catabolism, the patient was treated with a high-protein diet for 12 months. This has reversed the weakness and wasting, with improvement in muscle function, exercise tolerance, and growth.

Dichloroacetate tissue concentrations and its relationship to hypolactatemia and pyruvate dehydrogenase activation

Following a single oral dose of DCA to laboratory rats, peak hepatic tissue DCA concentration occurred at 3 hr. When given chronically for 7 days, DCA caused activation of the pyruvate dehydrogenase complex which returned to basal activity 24 hr following the final dose. Hepatic tissue DCA concentrations were maximally increased at 3 hr following the final dose, and the drug was eliminated slowly over 72 hr with a half-life of 9.74 hr. Liver and muscle showed similar DCA tissue concentrations following chronic administration.

Reversal of debrancher deficiency myopathy by the use of high-protein nutrition

A child with debrancher deficiency presented with myopathy, recurrent hypoglycemia, and growth failure. Evidence for enhanced gluconeogenesis was demonstrated by low postabsorptive gluconeogenic plasma amino acids, a marked fall in alanine during fasting, and a substantial rise in plasma glucose following protein ingestion. The patient was treated with high-protein nocturnal intragastric therapy, which resulted in marked improvement in exercise tolerance, muscle strength and mass, electromyographic findings, and growth.

Prolonged hypolactatemia and increased total pyruvate dehydrogenase activity by dichloroacetate

Dichloroacetate (DCA) given gastrically as a single dose to healthy, fed rats caused transient lowering of blood glucose, lactate, and pyruvate. Chronic daily dosing caused lowering of these metabolites and a delay in the return of lactate to basal levels for 48 hr after the final dose. DCA caused activation of the pyruvate dehydrogenase complex (PDHC), with acute multiple dosing or chronic daily dosing. The elevated active PDHC persisted for 12 hr following the final dose. In addition, total PDHC activity was increased with chronic dosing and persisted for 48 hr following the final dose. This increase was not blocked by protein synthesis inhibitors. DCA increased isolated hepatocyte [14C-1]pyruvate oxidation and activated hepatocyte PDHC. Glyoxylate and oxalate, hepatic metabolites of DCA, were inhibitory at similar concentrations.

Pyruvate decarboxylase deficiency in subacute necrotizing encephalomyelopathy

A partial deficiency of pyruvate decarboxylase (PDC) was demonstrated in a child with hyperlactatemia and progressive ataxia, bulbar paresis, ophthalmoplegia, and polyneuropathy. Subacute necrotizing encephalomyelopathy (SNE) was found at necropsy. The association of SNE and PDC deficiency has been reported rarely, but a review of the diverse metabolic defects associated with SNE suggests that decreased PDC activity may be the common feature of SNE.

Polyneuropathy in childhood

Polyneuropathy is an uncommon neurologic disorder that occurs in childhood. An evaluation of 61 patients over a period of seven years showed the Guillain-Barré syndrome and degenerative polyneuropathies to be the most common diagnoses. Other etiologies included metabolic, toxic, and neuropathies associated with systemic diseases. A group of idiopathic neuropathies was identified in which an unusual finding was a large subgroup of children with chronic or progressive central nervous system disease.