[Acute loss of vision in children]. / Pérdida aguda de visión en niños.

The differential diagnosis of acute loss of vision in children includes acute loss of vision due to retinal or optic nerve disease, and cortical blindness. The retinal disorders which may be mis diagnosed as optic neuritis include Leber neuroretinitis, Leber hereditary optic neuropathy, and Stargardt macular dystrophy. Retinal changes which evolve in neuroretinitis, and the pseudopapilledema in Leber heredity optic neuropathy are helpful in differentiating these disorders from optic neuritis. Stargardt macular dystrophy, a disorder associated with a variety of mutations, may be mis diagnosed as psychogenic visual loss due to the early normal appearance of the retina, and the loss of vision over a period of weeks. The differentiation of optic neuritis from anterior ischemic optic neuropathy (AION), depends upon the initial appearance of the optic disc (in AION either hyperemia due to reperfusion, or swelling and pallor if total infarction has occurred). The authors have described children with abrupt loss of vision during renal dialysis, whose risk factors for AION included systemic hypotension and intra ocular hypertension. Children with vigorous treatment of accelerated hypertension, and children with migraine and pro thrombotic disorders have also incurred AION. Thus, AION should be suspected when acute loss of vision occurs in association with certain ocular and systemic risk factors. In children capable of cooperating for visual field examination, the typical change in AION is an altitudinal defect, while optic neuritis it is a central scotoma. The association of optic neuritis with multiple sclerosis, DeVic disease, and with acute demyelinating1 encephalomyelitis require special consideration in regard to treatment and prognosis. Acute loss of vision due to cerebral cortical insults involves a large differential diagnosis which includes vascular, metabolic and infective disease; as well as disorders causing transitory blindness such as seizures and migraine

[Anterior ischemic optic neuropathy in children]. / Neuropatía óptica isquémica anterior en el niño.

A 5-year old girl with history of chronic renal failure due to dysplastic and polycystic kidney disease treated with peritoneal dialysis since birth wake up the the day after an scheduled uncomplicated peritoneal dialysis except for asymptomatic arterial hypotension with bilateral blindness. Neurological examination was normal except for absent light perception and tracking of optokinetic tape, dilated (7 mm) and unresponsive to light pupils, pale and slighted elevated disks with blurred margins and pale retina with irregular abnormal appearing vessels. Spinal fluid examination revealed no abnormalities except for slight pleocytosis (12 WBC, 68% mononuclears and 32% lymphocytes). MRI with gadollinium and MRA were normal. She received intravenous methyprednisolone for 3 days and intravenous and intraperitoneal antibiotics and intravenous acyclovir without improvement. She also received topical dorsolamide hydrochloride. Two year later she remained blind without light perception. Final diagnosis was anterior ischemic optic neuropathy. Pathogenesis, clinical picture, differential diagnosis and treatment of this condition in children are discussed.

Routine preoperative MRI and SEP studies in adolescent idiopathic scoliosis.

In this prospective study, 72 patients with the clinical diagnosis of adolescent idiopathic scoliosis underwent routine preoperative magnetic resonance imaging (MRI) scans and neurologic consultations. Forty-eight patients also had preoperative somatosensory evoked potentials (SEPs). All patients had normal neurologic examinations. Abnormal findings included two patients with Chiari type I malformation and one with a finding of a fatty collection in a vertebral body. In four cases, interpretation of the MRI was suspicious or equivocal, necessitating a computed tomography myelogram or other additional studies for clarification. Abnormal preoperative SEP results were obtained in three patients, none of which proved significant. All surgical patients underwent instrumentation and fusion without incident. The results indicate that routine preoperative SEP is not necessary. Routine preoperative MRI is probably not indicated in adolescent idiopathic scoliosis if the patient has a normal neurologic examination.

Dopa-responsive dystonia simulating cerebral palsy.

Five patients presented in infancy or early childhood with various combinations of pyramidal and extrapyramidal signs with normal cognitive function. Their perinatal courses were unremarkable. In each patient, initial impressions listed by several examiners included spastic diplegia or cerebral palsy. Later in each course, either extrapyramidal features or progression suggested dopa-responsive dystonia. In 4 of the 5 children, cerebrospinal fluid was obtained and disclosed reduced levels of biopterin, neopterin, and homovanillic acid in all 4. Levodopa therapy resulted in prompt improvement with normal function returning within 6 months. The disappearance of the "spasticity," extensor plantar responses, and extrapyramidal signs, following levodopa therapy, confirmed the diagnosis of doparesponsive dystonia in these patients. Three had apparently sporadic disease; the other 2 were siblings with an affected paternal grandmother. Three had onset in infancy with delayed sitting and walking before the appearance of overt dystonia; infantile onset is infrequent in dopa-responsive dystonia. The other 2 had normal milestones, but developed gait disorders with prominent imbalance in early childhood. The diagnosis of dopa-responsive dystonia should be considered in children with unexplained or atypical "cerebral palsy."

Efficacy of radiotherapy in optic gliomas.

Twenty-five children with optic gliomas were evaluated over a seven year period by sequential computed axial tomography in order to determine the efficacy of radiotherapy as a treatment modality. Indices of tumor progression or regression included both size and contrast enhancement characteristics. Twenty of 25 patients followed during this period received radiotherapy. Of these patients, ten had tumor regression, nine were stable, and one was worse. This result contrasts with five untreated patients, four of whom had tumor progression and one who was stable (x2 = 18.37, p less than .001). One of the children with tumor progression later received radiotherapy and demonstrated marked tumor regression. Of the 18 treated patients who could be tested reliably, visual function and/or regression occurred in seven children. None of the untreated patients improved. There were no definite complications of radiotherapy in this small group.

Cerebral dysfunction following infantile dietary chloride deficiency.

Twenty-two children who were chloride-depleted in infancy due to a chloride-deficient diet and who had resultant hypochloremic alkalosis were analyzed in regard to their signs and symptoms, metabolic studies, and growth parameters. Deceleration of weight, linear growth, and head growth occurred in most, and persistent growth failure occurred in some. The majority had cognitive deficits at follow-up. Comparison with growth parameters in a chronically malnourished group of children who had a variety of disorders revealed a similar degree of deceleration of weight (p = 0.50) and height (p = 0.70), but more severe deceleration of head growth (p = 0.01). Comparison with follow-up cognitive deficits reported in the United States medical literature in children with similar severity of nutritional deprivation indicates that the chloride-depleted infants had more frequent and more severe cognitive deficits (p = 0.09). Cognitive deficits have been documented in U. S. children who are nutritionally deprived only when disorders causing concomitant chloride depletion are responsible for the malnutrition.

Rapid resolution of organic mental syndrome in sickle cell anemia in response to exchange transfusion.

A 10-year-old boy with sickle cell anemia had a recurrent organic mental syndrome. On two occasions, symptoms and signs cleared promptly with exchange transfusion, and his neurologic condition was stable when the percentage of hemoglobin S was 19.4%.

Alpha-locus hexosaminidase genetic compound with juvenile gangliosidosis phenotype: clinical, genetic, and biochemical studies.

A 3-year-old boy developed progressive neurological deterioration in his third year, characterized by dementia, ataxia, myoclonic jerks, and bilateral macular cherry-red spots. Hexosaminidase A (HEX A) was partially decreased in the patient's serum, leukocytes, and cultured skin fibroblasts. Hexosaminidase was studied in serum and leukocytes from family members. Four members of the paternal branch appeared to be carriers of classical infantile Tay-Sachs allele, HEX alpha 2, probably receiving the gene from one great-grandparent of Ashkenazi origin. In the maternal branch, no one was a carrier of classical infantile Tay-Sachs disease, but five individuals were carriers of a milder alpha-locus defect. The patient, therefore, was a genetic compound of two different alpha-locus hexosaminidase mutations. At least 21 families with late-infantile or juvenile GM2 gangliosidosis have been reported, 18 of them with alpha-locus mutations, and three with beta-locus mutations. Genetic compounds of hexosaminidase have been reported in at least seven families, five with alpha-locus mutations and two with beta-locus mutations. The compound had the phenotype of infantile Tay-Sachs disease in one family, infantile Sandhoff disease in another, and the normal phenotype in the rest.

Increased intraventricular pressure without ventriculomegaly in children with shunts: "normal volume" hydrocephalus.

Five patients with shunt-dependent hydrocephalus were observed to have apparently normal ventricular size despite marked increases in ventricular pressure after shunt malfunction. Elastance (dP/dV) was determined in four of these patients by removing increments of cerebrospinal fluid and measuring the resulting pressure. These patients without ventricular enlargement and with markedly increased ventricular pressure had high elastance. This group of patients with "normal volume" hydrocephalus had distal shunt occlusions, in contrast to previously reported patients with cephalic shunt obstructions after ventricular decompression. Initial shunting in early infancy, prolonged shunt dependency, and lack of recent shunt revision were common factors in these patients. Markedly elevated pressure with normal volume is a threatening clinical entity, requiring prompt surgical intervention

HLA typing and Guillain-Barré syndrome.

In an effort to determine if there might be an association between Guillain-Barré syndrome and specific antigens of the HLA system, 18 patients with Guillain-Barré syndrome were typed for HLA-A, B, and D antigens. No statistically significant relationship was established by this study.

Neonatal polycystic encephalomalacia: four new cases and review of the literature.

Four patients with pathologically documented polycystic cavitation of the brain had an acute illness characterised by stupor, seizures, CSF erythrocytic and monocytic pleocytosis, increased CSF protein, and diminished CSF glucose. The acute phase was followed by chronic decerebation, disappearance of the CSF abnormalities, and radiological evidence of polycystic cavitation of the brain. In one patient Herpes simplex was isolated from a cutaneous vesicle. The CSF abnormalities in the disorder have received scant attention, and have not previously been correlated with the acute and chronic stages. Clearly some cases are associated with Herpes simplex virus. The clinical profile should now be sufficiently distinctive to permit future identification of the aetiology in more neonates.

Tissue carnitine in Reye syndrome.

Skeletal muscle carnitine palmityltransferase and muscle or liver carnitine content were determined in biopsies from children during and after attacks of Reye syndrome. No consistent abnormality of enzyme or cofactor was found. Reye syndrome is biochemically distinct from the clinically similar syndrome of systemic carnitine deficiency.

Pseudotumor cerebri of childhood.

In a study of 38 children with pseudotumor cerebri, the evaluation of the response to treatment received special emphasis. Sixteen children underwent spontaneous remission following diagnosis, or improved following sequential lumbar punctures. Sixteen other children were treated with corticosteroids. Of this group, four children who failed to respond to repeated lumbar punctures prior to the initiation of corticosteroid therapy, had their subsequent course on varying doses of steroids charted clinically and by frequent measurement of the CSF pressure. An Inverse relationship of steroid dosage to CSF pressure was documented, as was the children's dependence on corticosteroid therapy for continued remission as the pseudotumor cerebri ran its course. In twelve other children, treatment with corticosteroids may have been effective. Two children had neurosurgical procedures. Permanent visual deficit did not occur in any child.