Table of Contents
Definition / general | Diagrams / tables | Gross images | Microscopic (histologic) imagesCite this page: Luca DC. Age related changes. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/bonemarrowagerelatedchanges.html. Accessed June 3rd, 2023.
Definition / general
- Cellularity averages 79% at ages 0 - 9 years, 50% at ages 30 - 69 versus 29% at ages 70 - 79
- With aging, hematopoietic tissue is replaced by fat
- Deeper medullary areas are typically more cellular than subcortical areas
- B cell production declines with age (Curr Opin Immunol 2005;17:463) although the relative abundance of pro B, pre B, immature, naive and mature B cells usually does not change appreciably between ages 24 and 88 years
- Occasional patients have exceptionally low numbers of lymphocyte precursors (Blood 2003;101:576)
- Hypocellularity in elderly marrow may be due to increased apoptosis (Mech Ageing Dev 2000;117:57)
- Usually no spicules in bone marrow aspiration from very young children, perhaps due to very low or absent fat content