The evolving spectrum of 'non-classical' Diamond-Blackfan anaemia--a case of eADA positive pancytopenia in a young adult

Clinical and molecular characteristics of forty Chinese children with essential thrombocythemia: A single-center, retrospective analysis

Due to the infrequency of essential thrombocythemia (ET) in children, little is known about its pathophysiological mechanism. To learn about the clinical and molecular features of Chinese children with ET, we retrospectively analysed 40 children with ET in a single center from 2015-2021. More than half of the children (51.3%, 20/39) were asymptomatic at diagnosis. Nearly half of the children (48.7%, 19/39) had microvascular symptoms, including headache, dizziness, stomachache, and paresthesia. Only two cases experienced vascular events. The proportion of children with typical "driver gene mutations" (i.e., JAK2 p.V617F, CALR exon 9, or MPL exon 10 mutation) was low (12.5%, 5/40). The equivalent ratio of children carried atypical driver gene mutations; however, 30 (75%) patients did not harbour driver gene mutations. Children carrying JAK2 p.V617F had lower platelet count (938 × 10⁹ /L vs. 1654 × 10⁹ /L, p = 0.031) compared to those without driver gene mutations. Cases harbouring typical driver mutations had higher median WBC counts than those without driver gene mutations (15.14 × 10⁹ /L vs. 8.01 × 10⁹ /L, p = 0.015). Compared to those without driver gene mutations, cases carrying typical and atypical driver gene mutations were both younger (median ages were 12, 6, and 7 years old, respectively; p = 0.023). The most prevalent non-driver gene mutations and those mutations with prognostic significance in adult counterparts were less common in children with ET compared to adults with ET.

Diamond Blackfan anemia 2008-2009: broadening the scope of ribosome biogenesis disorders

PURPOSE OF REVIEW

Diamond Blackfan anemia (DBA) is an inherited bone marrow failure syndrome characterized by erythroid failure, congenital anomalies and predisposition to cancer. Recently, the notion of DBA as a disorder of ribosome biogenesis has been clarified. Correlations between molecular underpinnings and disease pathophysiology, while elusive, are beginning to emerge. Advances in these areas will be explored in this review.

RECENT FINDINGS

All known genes mutated in DBA encode ribosomal proteins associated with either the small (RPS) or large (RPL) subunit and in these cases ribosomal protein haploinsufficiency gives rise to the disease. The number of genes affected, their potential interactions with the environment and modifier genes, and the myriad of potential signaling pathways linking abortive ribosome synthesis to cell-cycle regulators may all contribute to disease heterogeneity. Genotype/phenotype relationships emerging over the past year promise to shed light on these complex interrelationships and their role in DBA pathophysiology.

SUMMARY

The nosology of DBA has recently expanded to include two distinct disease categories: a classical inherited bone marrow failure syndrome and a 'ribosomopathy'. The description of DBA as a ribosomopathy has provided a context for scientific inquiry analogous to the description of Fanconi anemia as a disorder of DNA repair.