Association of isochromosome (7)(q10) in Shwachman–Diamond syndrome with the severity of cytopenia

Abstract

Key Clinical MessageWe report two male siblings with SDS. They have the same compound heterozygous mutations. Only one of the siblings acquired cytogenetic abnormality of i(7q) 2 years after diagnosis, became transfusion‐dependent, and underwent allogeneic hematopoietic stem cell transplantation. These cases indicate that i(7q) is associated with significant cytopenia in SDS patients.

Isochromosome i(7)(q10) in Myelodysplastic Syndrome – Case Report

“…19 Generally, i(7)(q10) is observed in patients with Shwachman-Diamond syndrome, a hereditary syndrome which presents in childhood and includes cytopaenia, pancreatic failure, growth deficit, skeletal abnormalities, mental retardation and marrow failure. 20,21 Interestingly, Shwachman-Diamond syndrome has a higher probability of progression to MDS/AML, due to karyotypic instability caused by mutations in the SBDS gene that are related to numerical and structural abnormalities of chromosome 7. 22 According to the Severe Chronic Neutropenia International Registry, the incidence of MDS in individuals with Shwachman-Diamond syndrome is 8.1% over 10 years.…”

“…25 However, this relationship has been controversial in some studies, in which patients with clones i(7q) presented progressive bone marrow insufficiency with severe cytopaenia over time. 13,20,26,27 Despite this, Leung et al reported a case of transient MDS associated with i(7)(q10) in a child where, without intervention, bone marrow cytogenetics returned to normal and with complete hematologic recovery. 24 In the present study, a new karyotype analysis was requested in 2019 to assess disease remission, showing a reduction in the percentage of abnormal metaphases.…”