Convulsive status epilepticus management in adults and children: Report of the Working Group of the Polish Society of Epileptology.

INTRODUCTION: The Working Group was established at the initiative of the General Board of the Polish Society of Epileptology (PSE) to develop an expert position on the treatment of convulsive status epilepticus (SE) in adults and children in Poland. Generalized convulsive SE is the most common form and also represents the greatest threat to life, highlighting the importance of the choice of appropriate therapeutic treatment. AIM OF GUIDELINE: We present the therapeutic options separately for treatment during the early preclinical (>5-30min), established (30-60min), and refractory (>60min) SE phases. This division is based on time and response to AEDs, and indicates a practical approach based on pathophysiological data. RESULTS: Benzodiazepines (BZD) are the first-line drugs. In cases of ineffective first-line treatment and persistence of the seizure, the use of second-line treatment: phenytoin, valproic acid or phenobarbital is required. SE that persists after the administration of benzodiazepines and phenytoin or another second-line AED at appropriate doses is defined as refractory and drug resistant and requires treatment in the intensive care unit (ICU). EEG monitoring is essential during therapy at this stage. Anesthesia is typically continued for an initial period of 24h followed by a slow reversal and is re-established if seizures recur. Anesthesia is usually administered either to the level of the "burst suppression pattern" or to obtain the "EEG suppression" pattern. CONCLUSIONS: Experts agree that close and early cooperation with a neurologist and anesthetist aiming to reduce the risk of pharmacoresistant cases is an extremely important factor in the treatment of patients with SE. This report has educational, practical and organizational aspects, outlining a standard plan for SE management in Poland that will improve therapeutic efficacy.

Heterogeneity of histopathological presentation of pilocytic astrocytoma - diagnostic pitfalls. A review.

Pilocytic astrocytomas (PAs) are the most frequent primary astroglial tumours affecting children and adolescents. They occur sporadically or in association with a genetically determined syndrome - neurofibromatosis type 1. Classic PA usually manifests as a well-circumscribed, often cystic, slowly growing tumour, which corresponds to WHO grade I. The majority of pilocytic tumours arise along the neuraxis, predominantly in the cerebellum. They are associated with favourable long-term outcome or spontaneous regression, even after incomplete resection. However, the behaviour and prognosis might also be related to tumour histology and location. Pilomyxoid astrocytoma (PMA) represents a variant of classical PA with more invasive growth and increased risk of recurrences and dissemination. Typically, PAs exhibit distinct histology with biphasic architecture of loose, microcystic and compact, fibrillary areas. However, some tumours arise in an uncommon location and display heterogeneous histopathological appearance. The morphological pattern of PA can mimic some other glial neoplasms, including oligodendroglioma, pleomorphic xanthoastrocytoma, ependymoma or diffuse astrocytoma. Not infrequently, the advanced degenerative changes, including vascular fibrosis, and recent and old haemorrhages, may mimic vascular pathology. Sometimes, the neoplastic piloid tissue can resemble reactive gliosis, related to long-standing non neoplastic lesions. Not infrequently, PA exhibits histological features typical for anaplasia, including necrosis, mitoses and glomeruloid vascular proliferation that can suggest a diffuse high-grade glioma. However, even those PAs that lack distinct histological features of anaplasia can behave unpredictably, in a more aggressive manner, with leptomeningeal spreading. Genetic alterations resulting in aberrant signalling of the mitogen-activated protein kinase (MAPK) pathway have been considered to underlie the development of PAs. The most commonly identified KIAA1549-BRAF fusion is important for appropriate tumour molecular diagnosis. In this paper we summarize the clinicopathological presentation of PAs, with emphasis on their heterogeneous morphology, based on our own experience in the field of surgical neuropathology and the literature data. Diagnosis of pilocytic tumours requires careful analysis of clinical, histopathological and molecular features to avoid misinterpretation of these benign neoplastic lesions.

Meningioma with the unique coexistence of secretory and lipomatous components: a case report with immunohistochemical and ultrastructural study.

Meningiomas exhibit a broad spectrum of differentiation potency corresponding to different histological subtypes. The separate secretory or lipomatous transformation of meningothelial cells is uncommonly encountered in meningiomas classified into distinct secretory or lipomatous variants. The coexistence of these two different histological subtypes is extremely rare. We report an exceptional case of secretory meningioma associated with extensive lipomatous component in a 58-year-old woman. CT scan and MRI of the brain showed a well-defined tumor mass in the right temporal lobe with areas of adipose tissue and extensive surrounding brain edema. Microscopically, the tumor was composed of two components: whorls of meningothelial cells with numerous PAS-positive hyaline inclusions (pseudopsammoma bodies) and numerous mature adipocyte-like cells. The presence of neutral fat was confirmed by oil-red-O staining. The hyaline inclusions and tumor cells surrounding them showed strong immunoreactivity for EMA and CEA. Ultrastructural findings confirmed both secretory and lipomatous differentiation of tumor cells. The majority of lipidized neoplastic cells shared the features of meningothelial cells and adipocytes. Our result supports the opinion that lipomatous component ought to be considered as an advanced lipidization of neoplastic meningothelial cells rather than true metaplastic transformation of meningothelial cells into mature fat tissue. The present case of meningioma demonstrates a unique coexistence of secretory and lipomatous meningothelial components, reflecting the multipotency of phenotypic transformation of primary meningothelial cells.

Phenotypic characteristics of GFAP-positive oligodendroglial tumours. Part II: ultrastructural study.

Five cases of anaplastic oligodendrogliomas containing numerous GFAP-positive cells have been analysed by electron microscopy to establish the fine structural characteristics of neoplastic cells. Ultrastructurally, all tumours have revealed monotonous appearance typical of oligodendrogliomas, however some structural variability, particularly with reference to astrocytic differentiation, has been observed. The majority of neoplastic cells have shown the fine structural features of oligodendrocytes, accompanied by various numbers of intermediate cytoplasmic filaments. These filaments have been usually distributed in the perinuclear, less often in the peripheral, parts of the cytoplasm. The cells exhibiting features common to both oligodendroglial and astroglial cells might be regarded as an intermediate morphological form between these two cell types. True neoplastic astrocytes could be encountered only sporadically. The present electron microscopic studysupports the opinion that GFAP-positive oligodendroglial tumours contain heterogeneous neoplastic cell populations with the transitional cell types between oligodendroglial and astroglial lineage.

Ultrastructural characteristics of necrotic and apoptotic mode of neuronal cell death in a model of anoxia in vitro.

Increasing evidence suggests that two distinct modes of cell death, known as apoptosis and necrosis, are involved in many different pathological states. The morphological pattern of postanoxic changes has been widely studied in various experimental models, however the exact mechanism of neuronal cell death induced by ischaemic/anoxic insult is still not fully understood. The aim of this study was to determine the detailed ultrastructural criteria of postanoxic neuronal changes in in vitro model of anoxia. The electron-microscopic examination of organotypic cultures of rat hippocampus, exposed to 10- and 20-minute anoxic insult, revealed the morphological features typical for both necrotic and apoptotic neuronal cell death. Numerous neurones revealed a typical picture of passive necrotic lysis, such as advanced swelling of intracellular organelles associated with cell membrane disruption, whereas others clearly reflected an active apoptotic form of cell injury, consisting of condensation of nuclear chromatin with early preservation of cell membranes. However, there was also a subset of damaged cells sharing several features typical for both necrosis and apoptosis. These results add additional evidence to the previous studies suggesting not only that neurones injured by anoxic insult can die in a pure necrotic or apoptotic way but also that a continuum might exist between apoptosis and necrosis in certain pathological conditions.

Disseminated spinal and cerebral ependymoma with unusual histological pattern: clinicopathological study of a case with retrograde tumor spread.

The subject of this study is a case of anaplastic ependymoma originally arising from the central canal of the lower spinal cord followed by the 13 years history of events of upper spinal dissemination and retrograde intracranial spread. The specimens from four subsequent surgeries generally displayed the same microscopic features of neoplastic tissue and were consistent with the diagnosis of anaplastic ependymoma. The histological diagnosis was based upon the high cellularity, considerable nuclear atypia and pleomorphism, brisk mitotic activity, focally exhibited vascular endothelial proliferation and extensive necrosis. Apart from the typical pattern of ependymoma, the tumors contained areas composed almost entirely of large, uniform clear cells or pseudogemistocytes indicating the morphological heterogeneity of neoplastic cells population. The surgical specimens from four surgical resections shared light microscopic similarities suggesting spinal and intracranial dissemination from the primary spinal tumor. Since the retrograde spread via the cerebrospinal fluid (CSF) pathway is extremely rare, the authors of this study discuss the mechanism of such way of tumor metastases.

Giant cervico-thoracic schwannoma with long clinical history. Case report.

An unusual case of a giant intraspinal schwannoma in a 45-year-old woman with 14-year history of preoperative symptoms was presented. MRI of the spine revealed an intradural, extramedullary tumor extending from the intervertebral space C4/C5 to T4 vertebral body level (2 x 1.2 x 12 cm) and filling almost the entire spinal canal. Microscopical examination showed a typical neurinoma pattern with two distinct zones of Antoni A and Antoni B tissue. Some areas exhibited nuclear atypia and hyperchromasia reflecting the degenerative changes in this slowly growing nerve sheath tumor. A rich pericellular reticulin network was seen in the areas composed of Antoni A tissue. Immunohistochemically, the tumor cells were strongly positive for S-100 protein. The diagnostic difficulties in the presented case of longstanding schwannoma resulted in the late surgical treatment. The importance of the early diagnosis of spinal nerve sheath tumors for the patient's quick recovery is stressed.