Foetal onset of EIF2B related disorder in two siblings: cerebellar hypoplasia with absent Bergmann glia and severe hypomyelination.

Bi-allelic pathogenic variants in genes of the EIF2B family are responsible for Childhood Ataxia with Central nervous system Hypomyelination/Vanishing White Matter disease, a progressive neurodegenerative disorder of the central white matter. Only seven molecularly proven cases with antenatal onset have been reported so far. We report for the first time the neuropathological findings obtained from two foetuses harbouring deleterious variants in the EIF2B5 gene who presented in utero growth retardation and microcephaly with simplified gyral pattern that led to a medical termination of the pregnancy at 27 and 32 weeks of gestation. Neuropathological examination confirmed microcephaly with delayed gyration, periventricular pseudo-cysts and severe cerebellar hypoplasia. Histologically, the cerebellar cortex was immature, the dentate nuclei were fragmented and myelin stains revealed almost no myelination of the infratentorial structures. Bergmann glia was virtually absent associated to a drastic decreased number of mature astrocytes in the cerebellar white matter, multiple nestin-positive immature astrocytes as well as increased numbers of PDGRFα-positive oligodendrocyte precursors. Whole exome sequencing performed in the two foetuses and their parents allowed the identification of two EIF2B5 compound heterozygous variants in the two foetuses: c.468C > G p.Ile156Met and c.1165G > A p.Val389Met, the parents being heterozygous carriers. These variants are absent in the genome Aggregation Database (gnomAD r2.0.2). Contrary to the variant Ile156Met already described in a patient with CACH syndrome, the variant p.Val389Met is novel and predicted to be deleterious using several softwares. Neuropathological findings further expand the phenotypic spectrum of the disease that very likely occurs during early gestation and may manifest from the second half of pregnancy by a severe impairment of cerebral and cerebellar development.

Histologic analysis has a prognostical value in colorectal biopsies assessed for suspicion of graft-versus-host disease.

Gastrointestinal (GI) graft-versus-host-disease (GVHD) is a common and severe complication of allogeneic hematopoietic stem cell transplantation, but clinical and histological features are unspecific. The aim of this study was to correlate the histological GI GVHD grade with the clinical outcomes. In a retrospective study of 112 patients with clinically suspected GI GVHD, colonic biopsies were reviewed by three pathologists without knowledge of the corresponding clinical data and classified in four scores, according to the NIH Consensus Project recommendations: no GVHD, possible, probable, and unequivocal GVHD. At the end of the study, the histological and clinical data were confronted with the following results: clinical diagnosis of GI GVHD was established for 70 patients (62.5%) and histological scores correlated well with the clinical diagnosis (p < 0.001) and particularly with the prognosis (p < 0.05).When severe lesions were observed, the 1 year overall survival declined to 9%. None of the features reported in the literature to support GVHD diagnosis, eosinophil count, endocrine cells aggregate, immunohistochemical analysis (cytomegalovirus, CD123, chromogranin), did not help us for diagnosis. So routine histopathology alone without immunohistochemistry is a strong and reproducible tool to diagnose GI GVHD with the help of clinical and biological information, and most importantly, histological grading proved to be a powerful prognostic value.

[Incidental intraplacental gestational choriocarcinoma on a full-term placenta]. / Choriocarcinome gestationnel intra-placentaire de découverte fortuite sur un placenta à terme.

Of all the gestational trophoblastic tumors, the gestational choriocarcinomas have the worst prognosis and the most uncommon. We report a case diagnosed on a full-term placenta, discovered incidentally. The patient, gravida 2, para 1, delivered a hypotrophic infant at 38 weeks gestation. The placenta was examined in the laboratory to perform anatomo-pathological examination in order to explain the growth retardation. This study revealed the presence of an intraplacental choriocarcinoma. Disease staging was negative for both mother and child, and beta-HCG levels remained at zero. These two factors are rather good prognosis for choriocarcinoma. With this observation, we highlight the added-value of placental examination, which seems essential for any fetal pathology, pathological pregnancy and intrapartum complications. Anatomo-pathological examination must be meticulous and systematized in order to not overlook an intraplacental tumor.

[Placental pathology of uteroplacental vascular deficiency]. / Anatomie pathologique de l'insuffisance vasculaire utéroplacentaire.

The indications of the pathological examination of the placenta are mainly represented by uteroplacental vascular deficiency. The clinical context is often evocative, but it can sometimes be solely an intra-uterine growth retardation or an unexplained in utero fetal death. So, the pathological lesions of this uteroplacental vascular deficiency must be well-known to be correctly interpreted, for none of these lesions is truly specific. The pathological diagnosis is based on a group of macroscopic and microscopic arguments. Various physiopathological mechanisms, often imperfectly known, can be at the origin of an uteroplacental vascular insufficiency, but in the current position, the pathological examination does not allow etiopathogenic orientation. The development of the trophoblastic biopsies gives us access to a new material which, in parallel with the cytogenetic analysis, often allows us, in front of an unexplained intra-uterine growth retardation, to direct the diagnosis towards uteroplacental vascular insufficiency. The histological analysis of the chorionic villous sampling taken precociously during pathological pregnancies is thus a major diagnostic contribution. But especially, this analysis gives access to new information which, in the near future, will enable us to better define the pathological evolution of the lesions of hypoxic chorionic villous and to contribute to a better knowledge of this pathology which, under many aspects, still conceals many mysteries.