[Supratentorial neuroepithelial tumor with PLAGL1 gene fusion - a new type of morphologically variable pediatric brain neoplasm defined by a distinct DNA methylation class. A case report and literature review]. / Supratentorial'naya neiroepitelial'naya opukhol' so sliyaniem gena PLAGL1 u detei ­ novyi tip opukholi mozga s raznoobraznoi morfologicheskoi kartinoi i otlichitel'nym metilyatsionnym profilem(sluchai iz praktiki i obzor literatury).

BACKGROUND: Methylation analysis has become a powerful diagnostic tool in modern neurooncology. This technique is valuable to diagnose new brain tumor types. OBJECTIVE: To describe the MRI and histological pattern of neuroepithelial tumor with PLAGL1 gene fusion. MATERIAL AND METHODS: We present a 6-year-old patient with small right frontal intraaxial tumor causing drug resistant epilepsy. Despite indolent preoperative clinical course and MRI features suggesting glioneuronal tumor, histological evaluation revealed characteristics of high-grade glioma, ependymoma and neuroblastoma. RESULTS: Methylation analysis of tumor DNA confirmed a new type of a recently discovered neoplasm - neuroepithelial tumor with PLAGL1 fusion (NET PLAGL1). PCR confirmed fusion of PLAGL1 and EWSR1 genes. No seizures were observed throughout the follow-up period. There was no tumor relapse a year after surgery. CONCLUSION: Methylation analysis in neurooncology is essential for unclear tumor morphology or divergence between histological and clinical data. In our case, this technique confirmed benign nature of tumor, and we preferred follow-up without unnecessary adjuvant treatment.

[The structural basis of epileptogenesis in an adult patient: the comprehensive diagnostics experience]. / Strukturnaya osnova epileptogeneza u vzroslogo patsienta: opyt kompleksnoi diagnostiki.

On the example of the diagnosis of the structural basis of focal epilepsy in an adult patient, the possibilities of a multimodal and interdisciplinary approach to diagnosis, combining the latest methods of neuroimaging with the results of neurophysiological examinations, are considered. The interaction and high qualification of specialists in epileptology, neuroradiology and pathomorphology provide a high probability to determine the cause of the focal forms of epilepsy. Along with the introduction of super-inductive MR systems, it is important to use their capabilities correctly and optimize the scanning protocol for the individual characteristics of the patient. With a long-term pharmacoresistant course of focal epilepsy, accompanied by low quality of life, the progression of neurological deficits and the aggravation of cognitive and personality problems in patients, it becomes obvious that these patients, even with negative results of standard MRI, are candidates for a more in-depth comprehensive examination to identify the structural basis of epileptogenesis and subsequent epileptic surgery. However, the problem of epilepsy pseudoresistance should be considered, when a patient with uncontrolled seizures takes antiepileptic drugs for a long time in inadequate dosages. Modern comprehensive diagnostics offers new rational approaches to antiepileptic therapy indication on the part of the doctor, as well as to improve the patient's compliance to the treatment.

[Features of the neuroradiological picture of ganglioglioma on the example of 20 clinical cases]. / Osobennosti neiroradiologicheskoi kartiny gangliogliomy na primere 20 klinicheskikh sluchaev.

OBJECTIVE: To analyze the images obtained during pre-surgical neuroimaging in patients with gangliomas for the presence of specific signs and verification of the neoplastic process. MATERIAL AND METHODS: The results of presurgical MRI (3.0, 1.5 Tesla) of 20 patients with gangliomas were analyzed to identify specific signs of a neuronal-glial tumor and verify the neoplastic process based on the results obtained and a review of the literature. In addition to high-resolution MRI (HR MRI), various protocol modifications were applied to patients with epileptogenic pathological substrates of unclear etiology, including tractography (DTI) and contrast-free MR perfusion (ASL). In 5 cases, a multi-modal study was performed that combined the results of CT, routine MRI, HR MRI, functional MRI (fMRI) in various combinations and PET CT. RESULTS AND CONCLUSION: In 17 cases, patients underwent epileptic surgery. Three patients without epilepsy were operated on for a tumor diagnosed by radiological examination. In all 20 cases, gangliogliomas were verified, including 1 anaplastic, 1 infantile desmoplastic, and another patient had histological samples showing signs of a composite tumor. Combination with FCD IIIb was observed in 3 cases. Two patients had a double pathology (cases of tumors combination with lissencephaly and neuronal heterotopia) and another had a composite neuronal-glial tumor. In 15 cases, gangliogliomas showed neuroradiological features typical for dysembryoplastic neuroepithelial tumor (DNT) such as multicystic, nodular, and diffuse (dysplastic) described in the literature. In addition, in 9 cases, they had significant signs of neoplastic process such as contrast enhancement, continued growth and remodeling of the underlying bone. Verification of the neoplastic process based on the results of neuroradiological studies was difficult in 6 cases. In 2 cases, it was not possible to confirm the presence of neoplasm by radiological methods, and in 1 patient, the verification of the tumor during differential diagnosis took more than 8 years. The most common differential diagnosis was performed with DNT and FCD type IIb, which have a number of similar neuroradiological features.

[Clinical and morphological diagnosis of secondary hemophagocytic lymphohistiocytosis]. / Kliniko-morfologicheskaya diagnostika vtorichnogo gemofagotsitarnogo limfogistiotsitoza.

Secondary hemophagocytic lymphohistiocytosis (hemophagocytic syndrome, massive macrophage activation syndrome) is a rare, aggressive, severe syndrome with a frequent fatal outcome. The pathogenesis of the syndrome, the role of viral infection, and the development of an excessive, aberrant, and inflammatory response leading to multiple organ dysfunction and sepsis remain unclear so far. The paper presents the data available in the literature and describes the authors' own observation of secondary hemophagocytic lymphohistiocytosis in a 14-year-old girl who had Epstein-Barr virus infection and died of severe multiple organ dysfunction. The in vivo diagnosis was based on the typical clinical presentations of the disease, the detection of the virus by a polymerase chain reaction assay, and the determination of blood ferritin levels. Contemporary morphological diagnostic criteria (immunohistochemical reactions with anti-EBV and anti-CD68 monoclonal antibodies; Epstein-Barr virus encoded RNA (EBER) in situ hybridization) are shown; and clinical and pathological comparisons have been made.

[Two cases of bilateral lymphangiomatous palatine tonsil polyps in children]. / Nabliudenie dvukh sluchaev dvustoronnikh limfangiomatoznykh polipov nebnykh mindalin u detei.

Lymphangiomatous polyps of palatine tonsils are a rare condition, which is diagnosed with patomorphological study. About cases in total are reported in the literature, mostly with one-sided lesions. We managed to find only two reports of lymphangiomatous polyps of palatine tonsils in the available literature. The patients were children in both cases. We report our two cases of children with lymphangiomatous polyps of palatine tonsils.

[The anatomical features of the middle ear exerting the influence on the formation of exudative otitis media in the breast-fed infants of different gestational age]. / Anatomicheskie osobennosti srednego ukha, vliiaiushchie na formirovanie ékssudativnogo srednego otita u grudnykh detei razlichnogo gestatsionnogo vozrasta.

The objective of the present study was to elucidate the anatomical features of the structure of the middle ear and eustachian tube in the breast-fed infants of different gestational age that may be responsible for the formation of exudates (fluids). We have examined 150 temporal bones obtained from the children's cadavers that were allocated to three groups as follows: 50 temporal bones obtained at weeks 26-30 weeks of gestation (group 1), 44 bones 31-36 weeks of gestation (group 2), and 37-40 weeks of gestation (full-term babies, group 3),The analysis of the data obtained on an individual bases revealed either increase or decreases in the selected characteristics of the eustachian tube in comparison with the respective average values as well as the well apparent predominance of a single change or a combination of alteration of several parameters in one case in 26-30 weeks and 31-36 weeks groups. No significant changes were found in group 1. It is concluded that the presence of a single change or a combination of two or three abnormal changes in the parameters of the bone structures of the eustachian tube can affect the development of the secretory process in the middle ear especially in the children born after 36 weeks of pregnancy.

[Extrarenal rhabdoid tumor: A review of literature and a report of cases with atypical morphology]. / Ékstrarenal'naia rabdoidnaia opukhol'. Obzor literatury i opisanie sluchaev s netipichnoi morfologiei.

Extrarenal extracranial rhabdoid tumor (EERT) is a rare malignant pediatric tumor characterized by extremely aggressive behavior, rapid metastatic spread, low survival rates, and no targeted therapy. The morphological diagnosis of classical cases of EERT is not difficult and it is based on its characteristic histologic pattern and immunohistochemical findings in a relatively short time, which allows one to immediately initiate therapy. The paper describes two cases of ERRT in the complete absence of classical rhabdoid morphology, as revealed by light microscopy when the material was primarily assessed. The final diagnostic search could establish a diagnosis of EERT in both cases on the basis of immunohistochemical findings.

[Intrauterine Pneumocystis infection]. / Vnutriutrobnaya pnevmotsistnaya infektsiya.

Pneumocystosis is well known as an opportunistic infection that is presently most frequently registered in patients with HIV infection and in those with other immunodeficiency states. Earlier, after the Second World War, Pneumocystis pneumonia was most commonly detected in debilitated and premature children; nosocomial outbreaks of pneumocystosis were studied in detail in the 1960s and 1970s. The pathogen is transmitted through the air, but a number of references indicate that it can be transmitted through the placenta. Despite the increasing number of publications on pneumocystosis in pediatrics, physicians remain unfamiliar with this disease. The paper provides evidence that Pneumocystis jiroveci can infect the fetus in utero. If unrecognized, the disease can lead to a child's death due to severe respiratory failure. The authors describe their case of generalized pneumocystosis that has developed in a child with evidence of intrauterine infection (detection of the pathogen in the autopsy material and placenta and identification of serological markers in his/her parents). The issues that are associated with intrafamilial infection and a risk for in utero transmission of P. jiroveci are discussed.

[MRI-characteristics of epileptogenic supratentorial brain tumors in children].

OBJECTIVE: To analyze MR-images in patients with symptomatic epilepsy associated with the brain tumor. MATERIAL AND METHODS: MRI results of 52 patients with symptomatic epilepsy operated for tumors of supratentorial localization were analyzed. The most epileptogenic tumors with atypical MRI signs and subtle clinical presentation were identified. All patients with tumors were operated using different methods of surgical intervention. RESULTS: Dysembryoplastic neuroepithelial tumors (DNET), diffuse astrocytomas (DA) and gangliogliomas (GG) were the most frequent epileptogenic tumors. In all the cases of DNET and in 4 patients with GG, epileptic seizures were the first, and in 4 of 5 cases of DIO were the only clinical sign of tumor presence. In DNET, DA and GG, there was an iso- or hypointensive signal on T1 WI and a signal varying in intensity from moderate to hyperintense in T2 and FLAIR WI, while in cases with DNET and GG, no mass effect and perifocal edema was practically seen. The so-called «spume-like¼ (multicystic) structure was most clearly observed in FLAIR WI. No significant changes in the dimensions of the DNET and GG were identified. The combination of DNET with focal cortical dysplasia was noted in one case. In DA, it was difficult to distinguish the perifocal edema from tumorous tissue and normal brain tissues, and the growth potential of malformation was slow. CONCLUSION: Epileptogenic tumors can imitate the x-ray characteristics of each other, and mimicry to gangliogliomas, oligodendrogliomas and astrocytomas Gr I, II, and others. They are the most frequent causes of symptomatic focal epilepsy. The presence of these malformations is necessary to exclude first of all in all cases of pharmacoresistant epilepsy.

[Growing teratoma syndrome in a patient with intracranial germ cell tumor].

A six-year-old patient with non-germinomatous germ cell tumor of the chiasmatic-sellar area developed polyuria and polydipsia as the first symptoms of the disease. Then there were signs of precocious puberty and vision impairment. MRI examination revealed a shiasmatic sellar tumor and occlusive hydrocephalus. Tumor marker levels in blood serum were elevated. The alpha-fetoprotein level was increased 5-fold; human chorionic gonadotropin 20-fold. These levels increased over time. The patient received 2 cycles of PEI multiagent chemotherapy (Ifosfamide 1.5 g/m(2), Cisplatin 20 mg/m(2), Etoposide 100 mg/m(2)) during 5 days and 1 cycle of second-line multiagent chemotherapy (Cisplatin 100 mg/m(2) for 1 day and Endoxan 1500 mg/m(2) for 2 days). Despite the decrease in tumor marker levels to normal values, the patient's vision still deteriorated. MRI examination revealed that tumor size increased and its structure changed. Total tumor resection led to vision improvement and regression of intracranial hypertension. Histological analysis of tumor tissue only revealed a mature teratoma. This phenomenon, known as growing teratoma syndrome, is very rare among patients with intracranial non-germinomatous germ cell tumors.