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Infantile myositis is an inflammatory myopathy occurring in children under one year of age. This condition is extremely rare in the neonatal period and may be confused with other causes of generalized weakness. Creatine kinase activity is usually markedly elevated and electromyography demonstrates low amplitude, polyphasic motor unit activity. Muscle biopsy, necessary for diagnosis, documents characteristic findings of perifascicular atrophy and the presence of perivascular inflammatory cells. The diagnosis should be followed by corticosteroid treatment. The patient presented is the youngest biopsy-proved case of infantile myositis. In this report, his symptoms and clinical course are compared with those of previously described patients. The role of infectious agents and the immune state in the etiology of infantile myositis is considered.

The present studies were conducted to examine the possibility that the increased vulnerability of the newborn brain to hypoxia may be due to age-related differences in vascular thickness and contractility. Segments of rostral choroidal (RC), posterior communicating (PC), basilar (B), and common carotid (CC) arteries were taken from 3- to 7-day-old lambs (n = 11) and adult sheep (n = 8) and studied using standard in vitro techniques. In lamb cerebral arteries, maturation was associated with significant increases in vessel thickness and tension generation. Because the increases in tension generation (77, 90, and 135% in PC, B, and RC segments) were proportionately greater than the corresponding increases in thickness (45, 75, and 34% in PC, B, and RC), force per unit area increased with maturation in the cerebral arteries. In the CC segments, the age-related increases in thickness (117%) were greater than the increases in tension generation (30%), such that average force per unit area was actually greater in the lamb than in the sheep. In response to hypoxia (PO2 less than 15 torr), all vessels exhibited significant relaxation relative to normoxic controls, although the rates and magnitudes of relaxation varied considerably. In the sheep, the carotid exhibited rapid relaxation of small magnitude (21%), whereas the cerebral arteries relaxed more slowly and more completely (56, 52, and 45% in PC, B, and RC). In contrast, the lamb carotid segments relaxed more slowly than the cerebral arteries.(ABSTRACT TRUNCATED AT 250 WORDS)

The clinical courses of 18 preterm and term infants less than 1 month of age in whom brain death was diagnosed were retrospectively reviewed. Clinical diagnosis was determined neurologically and included (1) coma, (2) apnea, manifested by inability to sustain respiration, and (3) absent brainstem reflexes. Electroencephalograms were performed in all patients; 17 patients had adequate cerebral blood flow as estimated by radionuclide imaging. The results indicate that (1) neurodiagnostic tests such as electroencephalograms and radionuclide scanning reconfirmed clinically determined brain death in only one half to two thirds of patients; (2) electrocerebral silence in the absence of barbiturates, hypothermia, or cerebral malformations during 24 hours was confirmatory of brain death if the clinical findings remained unchanged; (3) absence of radionuclide uptake associated with initial electrocerebral silence was associated with brain death; (4) term infants clinically brain dead for 2 days and preterm infants brain dead for 3 days did not survive despite electroencephalogram or cerebral blood flow status; and (5) phenobarbital levels greater than 25 micrograms/mL may suppress electroencephalographic activity in this age group. The findings suggest that determination of brain death in the newborn can be made solely by using clinical criteria. Confirmatory neurodiagnostic studies are of value because they can potentially shorten the period of observation.

We report 3 children with reflex sympathetic dystrophy syndrome, review the literature, and discuss current concepts of diagnosis and management. In this disorder, pain, tenderness, swelling, vasomotor instability, and dystrophic skin changes frequently develop after minor injury. The clinical diagnosis is supported by osteopenia detected on radiographs and either increased or decreased radionuclide uptake on bone scan of the affected extremity. Treatment with a graduated program of physical therapy and transcutaneous electrical nerve stimulation is beneficial in almost all patients. In contrast to adults, the prognosis of childhood reflex sympathetic dystrophy syndrome is favorable; most children recover completely after one episode.

Brainstem auditory evoked responses (BAER) have been studied in several species and have provided a neurophysiologic 'window' into brainstem function. We have pursued further studies in the newborn lamb and adult sheep. BAER amplitude increased as the stimulus intensity increased from 45 to 95 dB and as the click frequency decreased from 88.8 to 22.2 Hz. BAER latency increased as both the stimulus intensity decreased and the click frequency increased. Developmental studies were performed between the 2nd and 35th day of life in the newborn lamb. No significant change in either latency, amplitude, or wave morphology was noted in contrast to other species where developmental changes are prominent. This was due to both the prenatal maturation of the lamb's brain and to the relatively short interval of the postnatal studies. We also studied the effect of prolonged severe hypoxia and acidosis on the BAER in the newborn lamb and found no significant change in either the amplitude or latency of the response.

Because of the controversy over applying adult clinical and laboratory criteria to children suspected of brain death, xenon computed tomographic cerebral blood flow (XeCTCBF) and near simultaneous scintigraphy were studied in 10 children. Six met the clinical criteria, one of whom had three indeterminate scintigrams with only central flow on XeCTCBF. Another had considerable flow with scintigraphy and XeCTCBF. One with clinical and autopsy brainstem death but preserved cortical function also had flow on both. This preliminary study establishes that brain scintigraphy is occasionally hypersensitive to insufficient cerebral flow and promises more accurate early assessment with XeCTCBF. The expectation is that XeCTCBF can refine the criteria for the earlier establishment of brain death.

Two isoelectric electroencephalograms obtained 24 hours apart support a clinical diagnosis of brain death in prolonged coma. Without documentation of electrocerebral silence, physicians are reluctant to discontinue vital support systems. A radionuclide bolus technique has been developed that documents the absence of cerebral blood flow in suspected brain death and supplements the flat EEG. In a recent review of this technique, all 27 adults who had EEG activity maintained the integrity of their cerebral blood flow. This contrasts to our studies of 5 children, all of whom demonstrated persistent EEG activity but had no evidence of cerebral blood flow by either the isotope bolus technique (5 patients) or cerebral angiography (4 patients). These children (mean age, 7 months) lacked cephalic reflexes and were maintained on assisted ventilation for an average of 15 days. Multiple electroencephalographic tracings persistently demonstrated low-voltage cortical activity over this time. Despite the lack of cerebral blood flow, all patients were continued on respiratory support. At autopsy, extensive brain liquefaction necrosis was noted. In comatose children, EEG monitoring may be of limited value while cerebral blood flow measurements can provide more practical and prognostic information.

Recent advances have made organ transplantation in newborns feasible, but the paucity of organs small enough for this age group remains a major limitation. Because anencephalic infants can survive for no more than a few weeks, they have been considered as possible organ donors for other infants. Under current law, however, they cannot be used as donors until their brain-stem activity ceases and the criteria for total brain death are thereby met. If anencephalic infants receive customary care, their solid organs usually undergo irreversible hypoxic injury during the process of dying and become unsuitable for donation by the time of death. We modified the medical care of 12 live-born anencephalic infants for one week to determine whether organ viability could be maintained and whether the criteria of total brain death could be met. Six received intensive care from birth, and six only when signs of imminent death developed. Only two infants met the criteria for total brain death within one week, and no solid organs were procured. Most organs were suitable for transplantation at birth. When intensive care was provided from birth, organ function was maintained; however, brain-stem activity ceased in only one infant within the first week. When intensive care was delayed until death was imminent, most organs were damaged to an extent that made them no longer suitable for transplantation. Our findings suggest that it is usually not feasible, with the restrictions of current law, to procure solid organs for transplantation from anencephalic infants.

Local cerebral blood flow was measured using stable xenon computed tomography in 21 children, 10 of whom were clinically brain dead and had electrocerebral silence as determined by electroencephalography. Radioisotopic brain scanning in 9 patients showed no visible cerebral activity in all patients and minimal residual sagittal sinus activity in 4. In this population, mean cerebral blood flow as measured by xenon computed tomography was 1.3 +/- 1.6 ml/min/100 gm. Respiratory support was discontinued in 8 patients, and 2 patients had cardiac arrest. Eleven profoundly comatose children who did not meet all clinical criteria for brain death and who had markedly suppressed but not isoelectric electroencephalograms had an average cerebral blood flow of 33.5 +/- 16.3 ml/min/100 gm. There was no difference in cerebral blood flow in those children who survived (30.4 +/- 16.3 ml/min/100 gm; n = 7) compared with those who died acutely (38.3 +/- 14.3 ml/min/100 gm; n = 4). Two patients who survived had average total flows of only 11.8 and 12.1 ml/min/100 gm. Our findings suggest that in infants and children older than 1 month, (1) cerebral blood flow below approximately 10 ml/min/100 gm is consistent with clinical brain death, (2) cerebral blood flow of less than 5 ml/min/100 gm is consistent with no flow as demonstrated by radionuclide techniques, and (3) flow of more than 10 to 15 ml/min/100 gm is associated with the potential for survival.

The determination of brain death during childhood has become increasingly important and in some ways controversial. This initial article reviews historical data and guidelines and provides a perspective for the recommendations which will be discussed in the second article (Part II).

The clinical course, laboratory data, outcome, and autopsy findings in 61 pediatric patients with suspected brain death were reviewed. In 58% of patients, the initial EEG was isoelectric, and cerebral blood flow was absent. In six of nine children, the initial EEG, which showed activity, became isoelectric by 72 hours. In no child without demonstrable cerebral flow did flow resume in later studies. In four of five children who had initial EEG activity despite absent cerebral flow, an isoelectric EEG developed on repeated study. The average time from initial insult until clinically suspected brain death was 29.5 hours and 61.5 hours until brain death was confirmed. The time from confirmation of brain death until discontinuation of life support systems was 32 hours in the majority of patients. Our current protocol for evaluating pediatric patients with suspected brain death is reviewed with emphasis on the clinical examination, laboratory studies, and use of serial EEGs and radionuclide cerebral blood flow determinations.

A 6-year-old girl presented with tonic-clonic seizures and generalized convulsions lasting several minutes. A serum drug screen revealed maprotiline, and the estimated intake was 12 mg/kg. Despite initial neurologic impairment on discharge, follow-up 6 months later showed normal neurologic function in the patient. This report describes that case and discusses the toxicity associated with maprotiline and its management.

Electrical injuries in children continue to account for substantial morbidity and mortality. This review describes the responsible pathogenetic mechanisms and five separate types of injury. Multisystem complications are discussed as well as current concepts of patient management. We emphasize the importance of prevention and include a pediatrician's "reminder" list for parent education.

In an effort to determine to what extent cerebral blood flow (CBF) varies in different parts of the brain during prolonged fetal hypoxia, we measured flow to 34 regions in 12 chronically catheterized fetal lambs 130 to 140 days gestation. Control values of PO2, PCO2 pH, heart rate, and blood pressure were obtained, and CBF was measured by use of radioactive labeled microspheres during a control period, during (15-, 30-, and 90-min) reduction of maternal inspired O2 concentration (fetal arterial PO2 was maintained at 12 to 15 torr), and 60 min after returning the ewe to room air. control blood flow to cortical, subcortical, and brainstem structures equaled 134, 186, and 254 ml x min-1 x 100 g-1, respectively. During hypoxia, CBF increased 92%, and 60 min after fetal oxygenation was restored, it remained 50% above control values. We noted a similar response in regional CBF to the cortex, subcortex, and brainstem during and after hypoxia. Blood flow to smaller areas within the three major regions were quite homogenous and had a similar pattern of response to hypoxia. We conclude that: (1) significant fetal regional CBF differences occurred in utero with brainstem and subcortical flows being substantially greater than flows to other regions of the brain; (2) during prolonged intrauterine hypoxia, total regional CBF increased 92%; (3) 1 hr after fetal oxygenation was restored, CBF still remained 50% above control values; and finally, (4) there was no significant preferential shunting of regional CBF during prolonged hypoxia in utero.

Myoadenylate deaminase (MADA) is an enzyme which participates in the purine nucleotide cycle necessary for energy production in human skeletal muscle. Approximately 35 patients with deficiency of this enzyme have been reported; one-half experienced their initial difficulties in childhood. Children with "primary" MADA deficiency typically have symptoms including muscle cramps, stiffness, and post-exercise myalgia and weakness. In "secondary" MADA deficiency, the clinical findings have been variable with delayed motor development, hypotonia, cardiomyopathy, delayed speech development, and generalized weakness. In most cases creatine kinase determinations, nerve conduction velocity studies, and routine muscle histopathology have been normal. Diagnosis has been established by demonstrating an absence of MADA activity by either direct muscle enzyme assay or histochemical staining. In this report we describe a 12-year-old boy with primary MADA deficiency and contrast his symptoms with those of previously described pediatric patients.

We investigated the effects of nifedipine, a calcium entry blocker, on the fetal and maternal circulation. Nifedipine was administered intravenously for 30 minutes to chronically instrumented pregnant ewes. Infusion of 5 micrograms.kg-1.min-1 resulted in a 30% to 50% increase in total and regional fetal cerebral blood flow to the brain stem, watershed, and subcortical regions (p less than 0.05), without a significant change in fetal oxygenation or cardiac output. Infusion of 10 micrograms.kg-1.min-1 decreased uterine blood flow by 21% (p less than 0.001) and fetal arterial oxygen content by 15% (p less than 0.01), with no further increase in fetal cerebral blood flow. Maternal arterial pressure decreased and heart rate increased (p less than 0.001) without variation of arterial blood gases. Significant plasma levels of nifedipine were detected in the fetal and maternal circulations. In view of the potential adverse effects on the fetus, further studies are needed before nifedipine is considered for use in human pregnancy.

Three cases are used to illustrate the computed tomography (CT) findings of tuberculous meningitis in infants and children. The clinical and laboratory findings of these patients are presented, and the differential diagnosis of viral, bacterial and fungal meningitis is reviewed. Tuberculous meningitis should be suspected, even in the infant or child with a negative tuberculin skin test, when a chronically ill patient presents with the acute signs of meningismus, the cerebrospinal fluid analysis demonstrates a low glucose and monocytosis, and cranial CT shows ventricular enlargement with prominent basal and sylvian fissure enhancement after intravenous contrast medium injection. The ease and safety of serial CT examinations make this procedure the ideal radiological method to follow the patient's course in order to evaluate the response to treatment.

The effects of nimodipine, on total and regional cerebral blood flow and cardiovascular function of the newborn chloralose-anesthetized lamb were investigated following intravenous bolus infusions (0.2, 0.6 and 2.0 micrograms/kg). At 2.0 micrograms/kg, the mean arterial blood pressure increased from 72.3 to 85.8 mm Hg. Total cerebral blood flow 45 min after infusion increased by 93%, as did regional flows to the gray (101%) and white (77%) matter and subcortex (108%). In a separate series of experiments we decreased arterial blood pressure from 71 to 40 mm Hg by phlebotomy. Nimodipine (30 micrograms/kg) bolus infusion significantly increased blood flow above control values to the total brain (41%), gray matter (53%), subcortex (76%) and brainstem (69%) 10 and 40 min later. However, no further increase in flow or decrease in cerebrovascular resistance was observed when compared to hypotension alone. Nimodipine appears to be well tolerated in the newborn lamb, and appears to increase cerebral flow during normotension. At the levels of hypotension used in the current experiments, nimodipine produced no further increases in cerebral blood flow.

The neuroradiological findings in four cases of primitive neuroectodermal tumor of the cerebrum are described. These highly malignant neoplasms of childhood present as large, enhancing cerebral masses with extensive neovascularity. Cerebrospinal fluid seeding is common and distant extraneural metastases may occur.