Diabetes Mellitus With Concurrent Cerebellar Degeneration and Necrosis in a Domestic Goose ( Anser anser domesticus)

A 5-year-old sexually intact male Toulouse goose ( Anser anser domesticus) was presented for ataxia, polyuria, and polydipsia. The goose was cachectic and exhibited head tremors. Results of plasma biochemical analysis and point-of-care glucometry revealed persistent hyperglycemia. Despite supportive care and oral glipizide, the goose died within 48 hours of presentation. Necropsy revealed severe pancreatic atrophy and fibrosis with regionally extensive cerebellar encephalomalacia and generalized Purkinje cell degeneration and necrosis. On a wet basis, hepatic zinc concentration was determined to be twice the reference interval by atomic absorption spectroscopy. Based on these findings, the pancreatic insufficiency with secondary diabetes mellitus was attributed to chronic zinc toxicosis. Despite birds' relative resistance to high blood glucose concentrations, prolonged hyperglycemia is suspected to have caused selective Purkinje cell degeneration and necrosis by glial activation, mitochondrial dysfunction, and glutamate toxicity, which resulted in the clinically observed motor deficits. This is consistent with experimental diabetic rat models. This case highlights the need for further investigation of the complex pathophysiology of diabetes mellitus in birds.

[Neuroimaging in epileptic encephalopathies in infants]

Magnetic resonance plays a vital role in the aetiological diagnosis of epileptic encephalopathies, since it is capable of identifying specific aetiological patterns or patterns which are suggestive of different conditions. We review the main magnetic resonance findings that are observed in symptomatic epileptic encephalopathies.

Abnormal parietal encephalomalacia associated with schizophrenia: A case report

RATIONALE

It is widely believed that structural abnormalities of the brain contribute to the pathophysiology of schizophrenia. The parietal lobe is a central hub of multisensory integration, and abnormities in this region might account for the clinical features of schizophrenia. However, few cases of parietal encephalomalacia associated with schizophrenia have been described.

PATIENT CONCERNS AND DIAGNOSES

In this paper, we present a case of a 25-year-old schizophrenia patient with abnormal parietal encephalomalacia. The patient had poor nutrition and frequently had upper respiratory infections during childhood and adolescence. She showed severe schizophrenic symptoms such as visual hallucinations for 2 years. After examining all her possible medical conditions, we found that the patient had a lesion consistent with the diagnosis of encephalomalacia in her right parietal lobe and slight brain atrophy.

INTERVENTIONS

The patient was prescribed olanzapine (10 mg per day).

OUTCOMES

Her symptoms significantly improved after antipsychotic treatment and were still well controlled 1 year later.

LESSONS

This case suggested that parietal encephalomalacia, which might be caused by inflammatory and infectious conditions in early life and be aggravated by undernutrition, might be implicated in the etiology of schizophrenia.

Bilateral cystic encephalomalacia following multiple intrauterine transfusions for anti-Kell isoimmunisation

Fetal and neonatal haemolytic diseases result from maternal allo-immunisation to fetal antigens. Maternal antibodies cross the placenta causing red cell haemolysis, resulting in fetal anaemia and, in severe cases, hydrops and perinatal death. Intravascular intrauterine blood transfusion (IUT) has markedly reduced perinatal mortality and is now a standard procedure. IUT is considered to be a safe procedure with fetal loss rate reported to be less than 5% and no reported increase in the rate of neurodevelopment impairment. In this report, we are presenting a case of bilateral cystic encephalomalacia following fetal anaemia secondary to anti-Kell iso-immunisation treated with multiple IUTs. Such a significant adverse outcome following IUT for anti-Kell iso-immunisation has not been reported in the literature. This case highlights the need for appropriate parental counselling and routine postnatal head ultrasound in all babies delivered following multiple IUTs.

Bovine diseases causing neurological signs and death in Mexican feedlots

The number of large feedlot operations, similar to that of USA and Canada, has notably increased in Mexico in the last three decades. Clinical and laboratory diagnoses of neurological diseases in feedlot cattle are crucial in Mexico and Central America because of the high incidence of bovine paralytic rabies (BPR). Because of its zoonotic potential, BPR must be promptly diagnosed and differentiated from other bovine neurological diseases such as thrombotic meningoencephalitis (TME), polioencephalomalacia (PEM) and botulism. More recently, BPR and botulism have been diagnosed with increasing frequency in Mexican feedlots. Neither BPR nor botulism has relevant gross lesions, thus post-mortem diagnosis without laboratory support is impossible. Herein, we describe five outbreaks of neurological diseases in Mexican feedlots in which BPR, botulism and PEM were diagnosed either independently or in combination. A diagram illustrating the most conspicuous pathologic findings and ancillary laboratory test required to confirm the diagnoses of these neurological diseases in feedlot cattle is proposed.

Neurological impairment in a surviving twin following intrauterine fetal demise of the co-twin: a case study

It has been established that twin pregnancies are at an increased risk for complications, including the risk of morbidity or mortality for one or both of the infants. Cerebral palsy and other associated neurological deficits also occur at higher rates in twin pregnancies. This report examines two cases of intrauterine demise of one twin with subsequent survival of the co-twin. In both cases, the surviving infant suffered significant neurological sequelae. Impairments observed in these two cases include multicystic encephalomalacia and periventricular leukomalacia as well as the subsequent development of cerebral palsy. This case study explores the predisposing factors, incidence, pathophysiology, consequences, and future research implications of these findings.

Structural lesion in the brain is a risk factor of childhood intractable epilepsy

Most of the intractable epilepsy cases are of paediatric age group. Eighty per cent of intractable epilepsy is symptomatic and have got structural lesion. These lesions are easily detectable by doing neuro-imaging. One hundred and four children with epilepsy were enrolled in two groups; in group A 52 intractable epilepsy patients and in group B 52 well controlled epilepsy patients from the child neurology unit of Bangabandhu Sheikh Mujib Medical University. Mean age of intractable group and well-controlled group was 4.45±3.66 years and 6.45±5.24 years respectively. Male were more in both groups. Abnormal neuro-imaging was significantly higher in intractable group; 78.8% children of the intractable epilepsy group had one or more structural lesions. Cortical atrophy, ventricular dilatation and encephalomalacia were the most frequent detectable lesions. Bilateral lesions and presence of multiple abnormalities were more in association with intractability. Structural lesions were detected more in cases with focal neurological deficit and structural abnormality having statistically significant difference.

Polioencephalomalacia in a llama

A 5-year-old, female llama (Lama glama) developed acute, progressive neurological disease, characterized by recumbency, muscle fasciculations, intermittent convulsions/opisthotonos, and absent menace responses. Postmortem histopathologic lesions, limited to the cerebral cortex, consisted of necrosis of the superficial and deep laminae. The clinical disease and microscopic lesions were consistent with polioencephalomalacia.

Early destructive lesions in the developing brain: clinical and electrographic correlates

OBJECTIVE

Early brain insults can cause cavitary lesions including porencephaly (POR) and multicystic encephalopathy (MCE). The objective of this study was to investigate clinical and electrographic correlates associated to these types of destructive brain lesions.

METHOD

Patients with POR and MCE were selected and submitted to clinical and Video-EEG monitoring. The following variables were analyzed: demographic data, type of lesion, presence of gliosis, perinatal complications, epilepsy, brain atrophy, and presence and frequency of epileptiform discharges.

RESULTS

Twenty patients were included, 65% males, 35% females, ages ranging from 1 to 40 years, 14 with MCE and 6 with POR. Eighteen patients had hemiparesis, 19 had epilepsy (current or in the past), seven of them had refractory seizures, and 16 had epileptiform discharges. All patients with MCE had gliosis while only 2 with POR had it.

CONCLUSIONS

No correlation was observed between type of lesion and clinical and electrographical outcome. However, a positive correlation was observed between frequency of discharges and presence of brain atrophy, and between MCE and gliosis.

Brain structure in prenatal stroke: quantitative magnetic resonance imaging (MRI) analysis

Neonatal stroke outcome studies demonstrate variable findings of either relatively spared intellectual function or persistent impairments. Volumetric measurement of the brain can provide more precise data on lesion-cognition outcomes. We studied 7 children with unilateral focal lesions from prenatal stroke. Whole-brain magnetic resonance imaging scans were analyzed to produce volumes of cortical gray matter, total white matter, cerebrospinal fluid, lesion, and lesion constricted fluid, and we ascertained the relationship of morphometric variables to intellectual and clinical outcome. Children with cystic encephalomalacia plus atrophy had poorer outcomes than children with atrophy or gliosis alone. These children also demonstrated the largest lesion size, smallest gray matter volume, and greatest proportion of hyperintense white matter in the affected hemisphere. Findings suggest that the type and size of the lesion, in addition to the integrity of white matter and residual cortex, may be better predictors of intellectual functioning than either of these indices alone.

Cerebral hemiatrophy (Dyke-Davidoff-Masson syndrome) in childhood: clinicoradiological analysis of 19 cases

BACKGROUND

The purpose of this study was to emphasize the clinical and imaging findings of 19 child cases of cerebral hemiatrophy.

METHODS

A total of 11 male and eight female patients underwent assessment with computed tomography and magnetic resonance imaging. The patients ranged from 1 to 17 years in age. The evaluated parameters were: location of the lesions, midline structural shift effect, ipsilateral calvarial and parenchymal changes.

RESULTS

Left cerebral hemiatrophy was seen in 14 of the cases while right cerebral hemiatrophy was observed in five cases. Unilateral calvarial thickening was seen in 11 cases, hyperpneumatization of paranasal sinuses in five, and hypoplasia of the middle frontal cranial fossa in three patients. Cerebral peduncle atrophy was noted in seven cases. In total, 11 patients had thalamic atrophy and lentiform nucleus hypoplasia. In one case, cerebral hemiatrophy was associated with ipsilateral large schizencephalic cleft and absence of the septum pellucidum, whereas in another case, there was diffuse cerebellar atrophy associated with cerebral hemiatrophy.

CONCLUSION

Computed tomography and, in particular, magnetic resonance imaging are the procedures of choice with respect to assessment of the etiology and extent of cerebral parenchymal involvement in cerebral hemiatrophy.

Cardiotocographic and Doppler Ultrasonographic Findings in a Fetus with Brain Death Syndrome

OBJECTIVE

The diagnosis of brain death syndrome by cardiotocography (CTG) and Doppler ultrasonography (US) is reported in a fetus at 35 weeks of gestation.

CASE REPORT

A 23-year-old, gravida 2, para 0, woman was referred to our hospital because of the absence of fetal movements. CTG showed fixed fetal heart rate (FHR) pattern. A detailed Doppler US examination of the fetus showed extensive cystic lesions of both cerebral hemispheres, polyhydramnios, total absence of neuromuscular parameters of biophysical profile (BPP) and the cessation of cerebral blood flow. Umbilical cord artery blood gas analysis showed pH 7.3, PaO2 30 mmHg and PaCO2 35 mmHg. A floppy male infant weighing 2,450 g was delivered vaginally at 36 weeks of gestation and the Apgar scores were 1 and 1 at 5 and 10 minutes, respectively. The neonate died 2 days after delivery. Postmortem examination of the brain showed diffuse, anoxic changes with multicystic encephalomalacia in both hemispheres and the brain stem. No other maternal or placental abnormalities were seen.

CONCLUSION

The possibility of intrauterine brain death should be considered in all cases of prolonged fixed FHR pattern, accompanied by absence of neuromuscular parameters of BPP, polyhydramnios and demonstrated cessation of cerebral blood flow by Doppler US. Increased awareness of this event may prevent unnecessary emergency cesarean section.

Growing skull fracture: a posttraumatic neosuture

CONTEXT

A case of a growing skull fracture presenting in adulthood is reported. Pertinent literature was reviewed with an emphasis on pathogenesis.

EVIDENCE ACQUISITION

A search through MEDLINE from 1994 through 2004 was used and supplemented by searches of secondary sources retrieved from referenced articles.

EVIDENCE SYNTHESIS

Current hypotheses for the pathogenesis of growing skull fractures were critically analyzed. A new hypothesis based in more recent data is proposed in an attempt to better understand this process.

CONCLUSIONS

The proposed hypothesis seems to explain better the timing in which the clinical features in growing skull fracture develop.

Polioencephalomalacia in Cattle: A Consequence of Prolonged Feeding Barley Malt Sprouts

Polioencephalomalacia (PEM) in ruminants has been recognized as a consequence of excess sulphur intake. The present study describes clinical, gross and histopathological findings of PEM following an abrupt change of diet in two ranches housing 2750 dairy and 2300 beef cattle. As a result of severe PEM, 256 cattle died or were slaughtered. Clinical findings included circling, hypersensitivity, excessive salivation, hypermetria, incoordination, blindness and death. The first clinical signs occurred in beef calves (6-8 months old) at a holding facility. Clinical signs of the disorder continued intermittently during the 5-month period in both ranches and were more evident in calves and lactating dairy cows. The affected cattle did not respond to thiamine injections. Clinical signs disappeared gradually following removal of barley malt sprouts from the diet. Although macroscopic lesions were not apparent in the brain tissues of some animals, histopathology typical of PEM was found in most cases: spongiosis in the neuropil and neuronal necrosis, haemorrhage, capillary hyperplasia, fibrinoid degeneration in arterioles, multifocal liquefaction necroses in the grey matter and abundance of gitter cells with vacuolar large cytoplasm. Sulphide in rumen fluid of a clinically affected animal was measured as 1.55 mg/dl, which is considerably higher than that collected from two control cows (mean 0.21 mg/dl). The total sulphur content of the diet containing barley malt sprouts was estimated to be 0.45%, which is also higher than the National Research Council (NRC) maximum tolerable levels. In conclusion, PEM can result from excess barley malt sprout intake because of its higher sulphur content. Clinical signs may occur shortly after the intake of barley malt sprout as outbreaks with a higher number of deaths or as an ongoing periodic condition.

Encephalomalacia with Enterococcus durans Infection in the Brain Stem and Cerebral Hemisphere in Chicks in Japan

Fourteen chicks, 7-12 days old, that died or had neurological signs (depression, paralysis, torticollis, incoordination, and rolling) were investigated pathologically and microbiologically. Variably sized foci of malacia were present within the parenchyma of the brain stem (cerebral peduncle, optic lobe, and medulla oblongata) and the cerebral hemisphere. Capillary thrombosis with congestion and hemorrhage was frequently observed within the malacia lesions. Gram-positive cocci were recognized in the blood capillary of malacia lesions. Bacteriologically, Enterococcus durans was isolated from the brain, liver, kidney, lung, and spleen. Detection of gram-positive cocci within the blood vessels in the malacia lesions observed in these cases may more strongly suggest the pathogenic role of E. durans on the malacia lesions in the brain stem and cerebral hemisphere.

Brain lesions in pigs dually infected with porcine reproductive and respiratory syndrome virus and pseudorabies virus

Four pigs were inoculated with an aerosol containing porcine reproductive and respiratory syndrome virus (PRRSV) followed 14 days later by inoculation with pseudorabies virus (PRV). The four dually infected pigs showed severe clinical signs, and one died on day 6 after infection with PRV. As demonstrated previously, the clinical disease was much more severe than that produced by either virus alone. All four dually infected pigs developed severe non-suppurative encephalitis, two had tonsillitis, two had necrotizing bronchiolitis, and one had lymphadenitis. The distribution of lesions corresponded closely with the detection of intranuclear inclusion bodies and PRV antigen. High numbers of TUNEL-positive cells detected in the thymus were associated with thymic atrophy.

Hyperprolactinemia presenting with encephalomalacia-associated seizure disorder and infertility: a novel application for bromocriptine therapy in reproductive endocrinology

OBJECTIVES

To describe successful oral bromocriptine therapy for hyperprolactinemia accompanied by seizure disorder and encephalomalacia identified during infertility evaluation.

MATERIALS & METHODS

A 32 year-old male with an unspecified seizure disorder was referred for infertility consultation. The initial seizure was at age 12, and was treated sequentially with phenytoin, phenobarbitol, and carbamazepine monotherapy which was maintained for six years and then discontinued. At age 26, a second seizure was experienced and 150mg lamotrigine b.i.d. was initiated. When the patient married it was discovered that erection was impossible; tadalafil was administered without success. At our center, total testosterone was low at 107ng/dl and semen analysis revealed oligoasthenozoospermia. Serum prolactin was 79.3ng/ml; visual field examination was normal. Brain MR showed no pituitary enlargement. However, encephalomalacia of the right occiptal lobe with porencephalic dilation of the occipital horn of the right lateral ventricle was present.

RESULTS

The patient was initially placed on 2.5mg/d bromocriptine but after three months only a nominal reduction of serum prolactin was achieved. Serum prolactin normalized (25.4ng/ml) after bromocriptine was increased to 7.5mg/d. Repeat semen analysis showed overall sperm concentration of 85M/ml, 30% motility and 12% normal forms morphology (Kruger strict criteria). Total testosterone level was 191ng/dl after final bromocriptine dose was attained, which was well tolerated.

DISCUSSION

Bromocriptine has an established role in the management of hyperprolactinemia, particularly in women. For males with elevated serum prolactin even when associated with focal encephalomalacia and seizure disorder, bromocriptine therapy can offer safe benefits including improved semen parameters and normal serum testosterone levels.

Encephalomalacic lesions in pigs dually infected with porcine reproductive and respiratory syndrome virus and pseudorabies virus

Four pigs (group 1) were infected with an aerosol containing porcine reproductive and respiratory syndrome virus (PRRSV) followed 7 days later by pseudorabies virus (PRV). Three further pigs (group 2) received PRRSV alone, two (group 3) received PRV alone, and two (group 4) remained as uninfected controls. Despite the admittedly small numbers of animals, the experiment appeared to throw light on aspects of synergy. Thus, the group 1 pigs showed severe neurological signs characterized by ataxia and muscular tremors. Total cell numbers in the bronchoalveolar lavage fluid were increased in all PRRSV-infected pigs, and PRRSV antigen was detected in the alveolar macrophages. Total cell numbers in the cerebrospinal fluid of group 1 pigs were considerably greater than those demonstrated in group 3, but no PRV antigen was found. Pigs of groups 1 and 2 showed pulmonary lesions, characterized by interstitial pneumonia and PRRSV antigen immunolabelling. Non-suppurative encephalitis was found in five of the six pigs of groups 1 and 3. In particular, one group 1 animal had severe necrotizing encephalitis with intranuclear inclusion bodies and associated immunolabelling of PRV antigen. The other three group 1 pigs had prominent malacic lesions, with macrophages. These neuropathological findings strongly suggested that PRRSV infection in pigs enhances the severity of brain lesions caused PRV.

Prognostic correlative values of the late-infancy MRI pattern in term infants with perinatal asphyxia

The aim of this study was to define the risk ratios of the late-infancy magnetic resonance imaging pattern for long-term outcome in term infants with perinatal asphyxia. We evaluated 65 term infants with perinatal asphyxia and performed magnetic resonance imaging examinations between 4-12 months of age. Magnetic resonance imaging scans were classified as follows: (1) periventricular leukomalacia in 21 (32%) infants, (2) marked cortical atrophy in 17 (26%) infants, (3) multicystic encephalomalacia in 10 (15%) infants, (4) deep gray matter involvement in 8 (12%) infants, (5) focal cortical involvement in 6 (9%) infants, (6) myelination delay in 3 (5%) infants. The overall outcome was favorable in 19 (29%) of 65 infants. Infants with diffuse cortical involvement (multicystic encephalomalacia and marked cortical atrophy) are four times (odds ratio: 4.4 and 4.1 respectively) more likely to attain the unfavorable outcome than the infants with other patterns of magnetic resonance imaging. Infants with focal cortical involvement had relatively favorable outcome in 60% of the cases. In conclusion, it appears that the overall outcome of infants with perinatal asphyxia correlated well with the magnetic resonance imaging patterns obtained between 4 and 12 months of age.

Pathogenesis of brain damage produced in sheep by Clostridium perfringens type D epsilon toxin: a review

Microvascular endothelial damage by the epsilon toxin of Clostridium perfringens type D appears to be the fundamental cause of cerebral parenchymal injury and lesions occur in a seemingly dose- and time-dependent manner. Large doses of circulating toxin produce a severe, generalised, vasogenic cerebral oedema and an acute or peracute clinical course to death. With lower doses of toxin, or in partially immune sheep, focal necrosis, often bilaterally symmetrical, occurs in certain selectively vulnerable brain regions, which appear to become fewer as the toxin dose is reduced. These cases follow a more protracted clinical course, but death is the usual outcome. The precise pathogenesis of the focal brain damage found in subacutely intoxicated sheep is unresolved, but several possible mechanisms are discussed.

[Multicystic encephalomalacia: MR imaging findings and clinical correlation]

PURPOSE

To review the MR imaging findings of multicystic encephalomalacia and to investigate the correlation between MR imaging and clinical findings.

MATERIALS AND METHODS

Twenty-one patients who presented with convulsion, mental-motor retardation and microcephaly and had evidence of multicystic encephalomalacia on MR images were included in this study. MR imaging patterns and clinical findings were reviewed. Consequently, we correlated MR imaging findings and clinical outcome.

RESULTS

All patients had cortical thinning, white matter destruction, atrophy and gliosis. Tetraplegia was seen in 17 out of 19 patients with mixed type cerebral palsy in two patients with diffuse or symmetric involvement on MR imaging. Both of the patients with mixed type cerebral palsy had basal ganglia involvement on MR imaging. Hemiplegia was seen in two patients with asymmetric involvement on MR imaging. Microcephaly was seen in 17 patients with diffuse or symmetrical, and in one patient with asymmetrical, involvement. Microcephaly and tetraplegia was seen in all patients with cerebellar and basal ganglion involvement.

CONCLUSION

Microcephaly and spastic tetraplegia were developed mostly in patients with diffuse involvement, whereas hemiplegia was seen in patients with asymmetric involvement. The clinical outcome was worse in patients with cerebellar and brainstem involvement. Therefore, we supposed that the symmetry of lesions and cerebellar or brainstem involvement might be used as a prognostic indicator.

Multicystic encephalomalacia after first-trimester intrauterine fetal death in monochorionic twins

Multicystic encephalomalacia occurs in approximately 20% of surviving cotwins after second- and third-trimester intrauterine fetal death of one twin in monochorionic pregnancies. We report a case of multicystic encephalomalacia after the demise of a cotwin in the first trimester diagnosed by magnetic resonance imaging and confirmed pathologically.

GROSS AND MICROSCOPIC LESIONS OF POLIOENCEPHALOMALACIA IN A LLAMA (LAMA GLAMA)

A 14-wk-old female llama (Lama glama) developed progressive neurologic disease characterized by stiff gait, circling, decreased mentation, and seizures. At necropsy, lesions were limited to the brain and consisted of bilateral necrosis of the cortical gray matter of the occipital lobes of the cerebral cortex. The primary microscopic alteration was bilateral laminar cerebrocortical necrosis, affecting mainly the deep laminae. Clinical disease, and gross and microscopic lesions were consistent with those of polioencephalomalacia.

Multicystic encephalomalacia

Antepartum death of a fetus in a multiple gestation can be associated with mortality or major morbidity in the survivor. This article reports a rare case of multicystic encephalomalacia that occurred in the survivor twin with antepartum death of its co-twin. Its pathology and pathogenesis are discussed with review of literature.

Polioencephalomalacia in captive harbour seals (Phoca vitulina)

In a colony of 11 harbour seals (Phoca vitulina Linné 1758) two episodes of central nervous disorders occurred within 2 years causing fatalities in seven adult animals. Clinical signs comprised dyspnoea, anorexia, apathy, incoordination and lateral recumbency. Vitamin B complex therapy was successful once. Pathomorphological examination of seven carcasses revealed acute and subacute malacia of the cerebellar grey matter. Additional acute malacic lesions located in the cerebral cortices and basal ganglia were observed. Mesencephalic nuclei were less severely affected and displayed acute changes. Despite intense search for environmental toxins and infectious agents, the cause of the fatalities remained undetermined. However, the type and pattern of the lesions are most suggestive of a thiamine deficiency.

Biochemical changes in apparently normal sheep from flocks affected by polioencephalomalacia

Blood samples were obtained for determination of the activities of lactate, pyruvate and erythrocyte transketolase, and faeces as samples for estimation of thiaminase, from 190 apparently healthy sheep from 19 flocks in which at least one animal had been diagnosed with polioencephalomalacia (PEM), from 59 control animals and from 7 affected by PEM. Feed and pasture grass samples were collected for thiaminase analysis and thiaminase was assayed in ryegrass and fescue. Decreased erythrocyte transketolase activity, accompanied by a corresponding rise in the thiamin pyrophosphate effect, and estimation of the thiaminase content in faeces, may be useful diagnostic procedures by which to identify periods of greater risk, during which animals could develop PEM. The changes in the diet probably acted as a primary factor for microbial production of thiaminases in replacement ewes. In these, the prevalence was higher in the spring months.

A case of pulmonary hypoplasia associated with intrauterine brainstem necrosis

An infant with intrauterine brain death accompanied by pulmonary hypoplasia is reported. The fetus was delivered after 36 weeks gestation, 5 weeks after fetal movements ceased. The child died 4 h after birth. Pulmonary hypoplasia and remote brainstem necrosis associated with multicystic encephalomalacia were found at autopsy.

CONCLUSION

These findings suggest that damage to brainstem respiratory centres had led to pulmonary hypoplasia through the absence of fetal respiratory movement.

Magnetic resonance imaging of cerebral cortical necrosis (polioencephalomalacia) in a dog

A 3-year-old neutered female mixed breed dog was examined because of severe, generalized seizure activity, tetraparesis, and encephalopathic signs. Cerebrospinal fluid (CSF) evaluation was unremarkable except for a mild increase in protein. Serum and CSF titers for infectious diseases were negative. Magnetic resonance (MR) imaging examination of the brain was performed and lesions were found within the cerebral gray matter of the temporal and parietal lobes. The lesions had increased signal intensity on T1, T2, and proton density-weighted images. There was mild inhomogeneous enhancement following intravenous contrast medium administration. Neurologic status improved and the seizures were well controlled, but the dog never regained normal mentation and euthanasia was performed 10 weeks after initial evaluation. At necropsy, severe cerebral cortical necrosis was found in the regions corresponding to the lesions seen on MR imaging examination. Large numbers of fat-containing macrophages (gitter cells) were found within these areas, and are thought to be responsible for the characteristic hyperintensity seen on the MR images.

Obstructive hydrocephalus caused by intraventricular collapse of malacotic brain. Case report

The authors present the case of a 68-year-old man who experienced acute obstructive hydrocephalus after having suffered an infarction in the occipital lobe. Histopathological and serial neuroimaging examinations revealed that portions of a large disintegrating occipital infarct had entered the lateral ventricle and obstructed the passage of cerebrospinal fluid (CSF). Ventricular drainage was performed for 2 weeks until the patient's hydrocephalus resolved. The CSF initially contained a high concentration of protein (1070 mg/dl), a high leukocyte count of 115 cells/mm3, and a rich fibrinous exudate. Findings in the present case indicate that collapse of a periventricular ischemic lesion into the ventricles may sometimes occur not only after cerebral hemorrhage but also after cerebral infarction.

Magnetic resonance imaging features of equine nigropallidal encephalomalacia

Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed.

Arthrogryposis and multicystic encephalopathy after acute fetal distress in the end stage of gestation

The natural history of the rare association "multicystic encephalopathy-arthrogryposis" was traced in a fetus carefully followed after artificial insemination. The fetus exhibited normal viability and brain morphology up to the 32nd week. At 36 weeks, active movements diminished and at 37 weeks, hydramnios and signs of fetal distress led to cesarean section. The infant presented with severe arthrogryposis of the limbs and spine, but not with the other elements of a long-lasting akinesia. US showed multicystic encephalopathy. Both the clinical and the neuropathological findings established that multicystic encephalopathy was neither the cause nor the sequential consequence of the fetal akinesia, but the result of a recent diffuse, acute malacic process that also involved the anterior horn cells. Acute fetal distress, responsible for major ischemic damage to CNS but compatible with fetal survival, remains an obscure condition which allows for the development of severe arthrogryposis in a few weeks.

Update on sulfur-related polioencephalomalacia

Sulfur-related polioencephalomalacia is frequently associated with a high total sulfur intake by ruminants. The onset of clinical signs coincides with excessive ruminal sulfide production. Measurement of ruminal gas cap hydrogen sulfide makes it possible to identify cattle with potentially hazardous total sulfur intake. Evaluation of all potential sulfur sources is necessary to estimate total dietary sulfur concentration, which can lead to prevention strategies.

Acquisition and transfer of new verbal information in amnesia: retrieval and neuroanatomical constraints

Four experiments examined new associative learning in amnesia by contrasting the performance of 2 amnesic participants-1 (C.C.) with basal forebrain damage and the other (R.H.) with medial temporal lobe damage--and 3 controls. Both amnesic individuals were severely impaired on explicit memory measures but showed intact perceptual priming. On the new associations measures, only C.C., not R.H., exhibited learning by producing correct targets (HIJACKER) in the absence of perceptual cues for them (e.g., STAFF shot ???). When the perceptual cue (e.g., MEDICINE cured _I_C_P) was provided, both C.C. and R.H. showed learning. Transfer to information containing conceptually related targets (e.g., TERRORIST or BELCH) was reliably observed only in C.C. This finding was replicated with further reduction in perceptual overlap across original (LIGHTNING torched JUNGLE) and transfer (LIGHTNING burned WILDERNESS) sentences. Together, these findings delineate the role of experimental conditions, severity of amnesia, and different neuroanatomical structures in mediating new verbal learning in amnesia.

Distribution of cells immunopositive for AM-3K, a novel monoclonal antibody recognizing human macrophages, in normal and diseased tissues of dogs, cats, horses, cattle, pigs, and rabbits

The monoclonal antibody AM-3K, which was developed using human pulmonary macrophages as the immunogen, immunocytochemically labels most human macrophages except for blood monocytes and dendritic cell populations. AM-3K also shows cross-reactivity in some animal species. To evaluate the usefulness of AM-3K, the present study investigated the detailed distribution of AM-3K-immunopositive macrophages in normal and diseased tissues of dogs, cats, horses, cattle, pigs, and rabbits. Zamboni's solution-fixed, paraffin-embedded sections were the most available for the immunocytochemistry with AM-3K. In all animal species examined, AM-3K labeled most macrophages in splenic red pulp, lymph node sinuses and thymus, and tissue macrophages in the interstitium of various organs and sites such as the kidneys, lungs, heart, pancreas, intestines, and skin. Alveolar macrophages and perivascular microglial cells were also immunoreactive for AM-3K. Interestingly, Kupffer cells of dogs, cats, and horses were labeled for AM-3K, but those of cattle, pigs, and rabbits were not. Furthermore, in tumor tissues and inflammatory lesions such as liver fibrosis and encephalomalacia that were obtained from dogs, infiltrating macrophages were stained with AM-3K, but not all infiltrating macrophages reacted to AM-3K. In addition, only 30-50% of pulmonary and peritoneal macrophages obtained from cats and dogs were reactive for AM-3K. AM-3K did not react with blood monocytes, dendritic cell populations, and osteoclasts. These observations indicate that AM-3K specifically labels most exudate and tissue macrophages in the animal species examined. However, the expression of antigens recognized by AM-3K on macrophages may be dependent on differential maturation stages or different functions evoked by some conditions. AM-3K immunoreaction products were seen on the cytoplasmic membrane of macrophages by immunoelectron microscopy. AM-3K would be useful for detection of macrophage populations in the animal species examined here.

Toxicology of Astragalus lusitanicus Lam

Astragalus lusitanicus is a toxic legume grown in Morocco and in some other Mediterranean countries. In small ruminants, poisoning by this plant is dominated by nervous signs characterized by many cycles of excitement-depression. Macroscopic examination of poisoned animals showed congestive lesions and oedema in the brain and lungs. Microscopic lesions consisted mainly of vacuolar degeneration in neurons, hepatocytes and in spleen and kidney cells. Serum activity of AST and CK as well as blood glucose and urea were increased as a result of poisoning. However, serum activity of alpha-mannosidase was not modified as is the case in locoism. Chemical investigations showed that A. lusitanicus does not contain swainsonine or miserotoxin and its selenium concentration is very low. However, this legume contains indolizidin alkaloids and a first compound was purified and identified.

Cerebellar encephalomalacia on magnetic resonance imaging after removal of acoustic tumor

MRI is widely used for postoperative surveillance of patients undergoing surgery for removal of acoustic neuroma. The purpose of this study was to investigate the frequency and pattern of postoperative changes in the cerebellum and brain stem on MRI after removal of acoustic neuroma. A retrospective study was conducted in 30 consecutive patients who underwent postoperative MRI between 1994 and 1995. The timing of the scans after surgery ranged from 12 months to 10 years. T2 -weighted turbo spin-echo images revealed cerebellar encephalomalacia in 17 of 30 cases. Cerebellar encephalomalacia was found more consistently in patients who had large tumors and was more frequent after the suboccipital approach. Encephalomalacia is largely caused by gliotic changes in the adjacent cerebellar tissues after tumor removal.

Association of excess sulfur intake and an increase in hydrogen sulfide concentrations in the ruminal gas cap of recently weaned beef calves with polioencephalomalacia

During a 2-week period, 16 of 150 recently weaned calves developed signs of polioencephalomalacia (PEM). One calf was examined and treated at our veterinary teaching hospital and a necropsy was performed on a calf that died. During the peak of the outbreak, clinicians visited the ranch. Ruminal hydrogen sulfide (H2S) and blood thiamine concentrations were measured in 10 clinically normal penmates of PEM-affected calves. Ruminal H2S concentrations were high (> 0.695 mg/L [> 500 ppm]) in all cattle (mean, 12.19 mg/L [8,770 ppm]). All blood thiamine values were within the reference range. Within 12 hours after measurement of blood thiamine concentrations, 2 of the calves from which samples were obtained developed clinical signs of PEM. Dietary analysis revealed an estimated sulfur intake of 0.9% per calf on a dry-matter basis. Hay contributed most of this sulfur. In the investigation reported here, an outbreak of PEM was associated with high ruminal H2S concentrations and excess sulfur intake without evidence of thiamine deficiency.

Amprolium-induced cerebrocortical necrosis (CCN) in dromedary racing camels

Amprolium was successfully used to induce cerebrocortical necrosis (CCN) in dromedary racing camels, only when they were fed on a barley diet. Camels which were fed on hay ad libitum did not suffer form CCN, although their thiamine pyrophosphate (TPP) reached similar levels as in camels fed on barley. The reason for this phenomenon is discussed. Five camels which suffered from CCN had TPP values of 80-115% and were euthanized on humane grounds when they were in lateral recumbency. Pathohistological investigations revealed a polioencephalomalacia of the dorsal cerebral cortex with oedema and status spongiosus. Cerebral autofluorescence was observed under ultraviolet light. The major clinicopathological changes were a slight anemia and a decreased potassium value whereas glucose, muscle enzymes, leucocyte counts and differential counts were elevated. A TPP effect of 12% was found during this study in healthy dromedary racing camels and symptoms were observed when TPP values reached 80-115%. The test is now being widely used during the camel racing season.

Repin-induced neurotoxicity in rodents

Russian knapweed is a perennial weed found in many parts of the world, including southern California. Chronic ingestion of this plant by horses has been reported to cause equine nigropallidal encephalomalacia (ENE), which is associated with a movement disorder simulating Parkinson's disease (PD). Repin, a principal ingredient purified from Russian knapweed, is a sesquiterpene lactone containing an alpha-methylenebutyrolactone moiety and epoxides and is a highly reactive electrophile that can readily undergo conjugation with various biological nucleophiles, such as proteins, DNA, and glutathione (GSH). We show in this study that repin is highly toxic to C57BL/6J mice and Sprague-Dawley rats and acutely induces uncoordinated locomotion associated with postural tremors, hypothermia, and inability to respond to sonic and tactile stimuli. We also show that repin intoxication reduces striatal and hippocampal GSH and increases total striatal dopamine (DA) levels in mice. Striatal microdialysis in rats, however, has demonstrated a significant reduction of extracellular DA levels. These findings, coupled with the absence of any demonstrable change in striatal DOPAC levels, suggest that repin acts by inhibiting DA release, a hypothesis that is further supported by our demonstration that, in cultured PC12 cells, repin inhibits the release of DA without affecting its uptake. We believe, therefore, that inhibition of DA release represents one of the earliest pathogenetic events in ENE, leading eventually to striatal extracellular DA denervation, oxidative stress, and degeneration of nigrostriatal pathways. Since the neurotoxic effects of repin appear to be mediated via oxidative stress, and since repin is a natural product isolated from a plant in our environment that can cause a movement disorder associated with degeneration of nigrostriatal pathways, clarification of the mechanism of repin neurotoxicity may provide new insights into our understanding of the pathogenesis of PD.

Encephalomalacia associated with vitamin E deficiency in commercially raised emus

Thirteen of 64 emus on a commercial emu farm in Ohio exhibited neurological signs that included backward staggering, incoordination, generalized weakness, and sitting on their hocks with head retracted backward. Eight of the birds showing such signs were found dead. Two of these emus were necropsied, and no significant gross lesions were observed. Major histopathological lesions were found in the cerebellum and included multiple malacic foci in association with neuropil rarefaction and astrogliosis within the white matter of folia. In addition, the hepatic vitamin E level of one emu was determined at the Michigan State University Animal Health Diagnostic Laboratory (MSU-AHDL) to be 14.61 micrograms/g dry weight. This vitamin E level was in the lower percentile (35%) of 30 emu liver samples examined at MSU-AHDL. A diagnosis of vitamin E-associated encephalomalacia was made based on clinical signs, gross and histological lesions, and liver vitamin E levels.

Clinical and pathological aspects of an outbreak of equine leukoencephalomalacia in Spain

In 1988 an outbreak of leukoencephalomalacia was diagnosed in equids that had eaten corn with a pinkish fungal growth. The fungus was then identified as Fusarium moniliforme. The main symptoms observed appeared acutely and were overexcitement, blindness, incoordination, facial paralysis and death within 24 h. The main pathological changes were restricted to the central nervous system. Macroscopically they consisted of hyperemia and haemorrhages, the consistency was friable and the gyri were somewhat flattened. Microscopically, the lesions were profuse and had extensive haemorrhages, and numerous neurons appeared in different stages of degeneration and necrosis, with satellitosis and neuronophagia. Perivascular cuffs formed by macrophages, plasma cells and lymphocytes were also observed. These lesions were present in both brain and cerebellum, with a marked oedema and massive necrosis of the Purkinje cell layer of the latter.