Fetal cerebral hemorrhage due to X-linked GATA1 gene mutation

Acute fetal leukemia: When should it be suspected? What assessment should be performed? A case series and review of literature

INTRODUCTION

Acute fetal leukemia is rare and characterized by a very poor prognosis. The aims of this study were to identify cases of acute fetal leukemia and to describe ultrasound and fetopathological findings that should lead to a suspicion of this diagnosis, as well as the investigations required to confirm it.

METHODS

A national retrospective study was conducted. Clinical data, prenatal ultrasounds and postmortem findings of fetal acute leukemia cases were collected and analyzed.

RESULTS

We collected seven cases: four in utero fetal deaths, two neonatal deaths and one termination of pregnancy. Prenatal ultrasounds showed fetal hydrops (42.9%) associated with hepatosplenomegaly (100%). In addition, post-mortem examination (n = 6) suggested a Down syndrome in one case and showed other organomegaly (83.3%) due to blastic infiltration, mainly in the liver, along with extrahepatic multivisceral hematopoiesis. Immunostainings allowed to specify the type of leukemia (71.4%). In one case, diagnosis was made on blood smear and flow cytometry was performed on fresh blood samples. All cases corresponded to acute myeloid leukemia. Karyotype was abnormal in 4 cases (66.7%), including one free trisomy 21, two mosaic trisomy 21 and one chromosome 15 deletion. GATA1 gene mutations were identified in two cases: one mosaic trisomy 21 and one with normal karyotype.

CONCLUSION

Any hepatosplenomegaly associated with fetal hydrops and a negative immune, infectious, and metabolic work-up, should suggest acute fetal leukemia and prompt additional investigations.

COL4A1/COL4A2 and inherited platelet disorder gene variants in fetuses showing intracranial hemorrhage

BACKGROUND

Variants of COL4A1/COL4A2 genes have been reported in fetal intracranial hemorrhage (ICH) cases but their prevalence and characteristics have not been established in a large series of fetuses. Fetal neonatal alloimmune thrombocytopenia is a major acquired ICH factor but the prevalence and characteristics of inherited platelet disorder (IPD) gene variants leading to thrombocytopenia are unknown. Herein, we screened COL4A1/COL4A2 and IPD genes in a large series of ICH fetuses.

METHODS

A cohort of 194 consecutive ICH fetuses were first screened for COL4A1/COL4A2 variants. We manually curated a list of 64 genes involved in IPD and investigated them in COL4A1/COL4A2 negative fetuses, using exome sequencing data from 101 of these fetuses.

RESULT

Pathogenic variants of COL4A1/COL4A2 genes were identified in 36 fetuses (19%). They occurred de novo in 70% of the 32 fetuses for whom parental DNA was available. Pathogenic variants in two megakaryopoiesis genes (MPL and MECOM genes) were identified in two families with recurrent and severe fetal ICH, with variable extraneurological pathological features.

CONCLUSION

Our study emphasizes the genetic heterogeneity of fetal ICH and the need to screen both COL4A1/COL4A2 and IPD genes in the etiological investigation of fetal ICH to allow proper genetic counseling.

Diagnostic Value of Sylvian Fissure Hyperechogenicity in Fetal SAH

BACKGROUND AND PURPOSE

Fetal SAH is an intracranial malformation. The typical diagnostic features of fetal SAH in ultrasound have not been reported. This study aimed to evaluate the diagnostic value of Sylvian fissure hyperechogenicity by prenatal ultrasound in fetuses with SAH.

MATERIALS AND METHODS

The features on ultrasound and MR imaging of 10 fetuses with SAH were reviewed and summarized. The diagnostic value of the Sylvian fissure in fetal SAH by prenatal ultrasound was evaluated.

RESULTS

The typical and most obvious manifestations of SAH during the prenatal period were hyperechogenicity in the subarachnoid cavity, especially in the Sylvian fissure; all 10 cases (10/10) had such manifestations. Other manifestations included a hyperecho in other sulci (6/10), especially in the subfrontal sulcus, superior temporal sulcus, or parieto-occipital sulcus; a hyperecho in the cisterns (8/10), especially in the suprasellar cistern, posterior cranial fossa, cisterna ambiens, or quadrigeminal cistern; and a hyperecho around the anterior and posterior longitudinal fissures (2/10). Combined hemorrhage in the parenchymal layer or ventricles (9/10) was found. In addition, Doppler ultrasound showed that the peak flow velocity in the MCA increased in 6 cases (6/10).

CONCLUSIONS

The homogeneous hyperechogenicity of the Sylvian fissure is an important clue for detecting and diagnosing fetal SAH by prenatal ultrasound. A diagnostic approach has been proposed for fetal SAH, which has great significance in further prognosis.

GATA-1 Defects in Diamond-Blackfan Anemia: Phenotypic Characterization Points to a Specific Subset of Disease

Diamond−Blackfan anemia (DBA) is one of the inherited bone marrow failure syndromes marked by erythroid hypoplasia. Underlying variants in ribosomal protein (RP) genes account for 80% of cases, thereby classifying DBA as a ribosomopathy. In addition to RP genes, extremely rare variants in non-RP genes, including GATA1, the master transcription factor in erythropoiesis, have been reported in recent years in patients with a DBA-like phenotype. Subsequently, a pivotal role for GATA-1 in DBA pathophysiology was established by studies showing the impaired translation of GATA1 mRNA downstream of the RP haploinsufficiency. Here, we report on a patient from the Dutch DBA registry, in which we found a novel hemizygous variant in GATA1 (c.220+2T>C), and an Iranian patient with a previously reported variant in the initiation codon of GATA1 (c.2T>C). Although clinical features were concordant with DBA, the bone marrow morphology in both patients was not typical for DBA, showing moderate erythropoietic activity with signs of dyserythropoiesis and dysmegakaryopoiesis. This motivated us to re-evaluate the clinical characteristics of previously reported cases, which resulted in the comprehensive characterization of 18 patients with an inherited GATA-1 defect in exon 2 that is presented in this case-series. In addition, we re-investigated the bone marrow aspirate of one of the previously published cases. Altogether, our observations suggest that DBA caused by GATA1 defects is characterized by distinct phenotypic characteristics, including dyserythropoiesis and dysmegakaryopoiesis, and therefore represents a distinct phenotype within the DBA disease spectrum, which might need specific clinical management.

Genetic Profiling of Idiopathic Antenatal Intracranial Haemorrhage: What We Know?

Intracranial hemorrhage (ICH) is reported in premature infants and rarely, in prenatal life. Fetal ICH can be accurately identified in utero and categorized by antenatal sonography and/or MRI. Infectious disease, maternal drug exposure, alloimmune thrombocytopenia, maternal trauma, coagulation disorders and twin-to-twin transfusion syndrome can cause fetal ICH. However, in many cases, the cause is not identified and a genetic disorder should be taken into consideration. We conducted a review of the literature to investigate what we know about genetic origins of fetal ICH. We conducted targeted research on the databases PubMed and EMBASE, ranging from 1980 to 2020. We found 311 studies and 290 articles were excluded because they did not meet the inclusion criteria, and finally, 21 articles were considered relevant for this review. Hemostatic, protrombotic, collagen and X-linked GATA 1 genes were reported in the literature as causes of fetal ICH. In cases of ICH classified as idiopathic, possible underlying genetic causes should be accounted for and investigated. The identification of ICH genetic causes can guide the counselling process with respect to the recurrence risk, in addition to producing relevant clinical data to the neonatologist for the optimal management and prompt treatment of the newborn.

Antenatal diagnosis of fetal intraventricular hemorrhage: systematic review and meta-analysis

AIM

To determine how the severity of antenatally diagnosed germinal matrix-intraventricular hemorrhage (GMH-IVH) relates to morbidity and mortality, and to explore potential risk factors.

METHOD

We conducted a systematic review and individual patient data meta-analysis of antenatally diagnosed fetal GMH-IVH. The primary outcomes were mortality and morbidity. Potential associations with clinical factors during pregnancy were explored. Analysis employed Fisher's exact test and logistic regression.

RESULTS

We included 240 cases from 80 studies. Presence of venous infarction was associated with mortality (odds ratio [OR] 4.3, 95% confidence interval [CI] 1.4-13.25), motor impairment (OR 103.2, 95% CI 8.6-1238), epilepsy (OR 6.46, 95% CI 2.64-16.06), and developmental delay (OR 8.55, 95% CI 2.12-48.79). Shunt placement was associated with gestational age at GMH-IVH diagnosis and in utero progression. Many cases had uncomplicated pregnancies but possible co-occurring conditions included twin gestation, small for gestational age, and congenital anomalies.

INTERPRETATION

Severity of fetal GMH-IVH, specifically venous infarction, is associated with overall mortality and morbidity. Risk factors for fetal GMH-IVH are poorly understood and controlled studies are required.

WHAT THIS PAPER ADDS

Preterm germinal matrix-intraventricular hemorrhage (GMH-IVH) grading can be applied to fetuses. Many fetal germinal matrix hemorrhages occur in otherwise typical pregnancies. Half of fetuses with post-hemorrhagic ventricular dilatation receive a shunt after delivery. Fetuses with grade I or II GMH-IVH have few sequelae. Fetuses with periventricular hemorrhagic infarction have a high burden of motor impairment.