From the Guidelines
Bone marrow inflammation, also known as Myelitis, can cause significant damage, including fibrosis, anemia, and impaired blood cell production.
Key Effects of Myelitis
- Fibrosis: Inflammation can lead to the formation of scar tissue in the bone marrow, known as fibrosis, which can disrupt normal blood cell production 1.
- Anemia: Myelitis can cause a decrease in red blood cell production, leading to anemia, as seen in primary myelofibrosis (PMF) 1.
- Impaired blood cell production: Inflammation can affect the production of other blood cells, such as white blood cells and platelets, leading to various complications.
Diagnostic Considerations
The diagnosis of PMF, a condition characterized by bone marrow inflammation and fibrosis, requires careful morphologic assessment and the presence of specific criteria, including megakaryocyte proliferation and atypia, and the absence of other myeloid neoplasms 1.
Clinical Implications
The damage caused by bone marrow inflammation can have significant clinical implications, including palpable splenomegaly, leukoerythroblastosis, and increased serum lactate dehydrogenase levels 1.
From the Research
Damage Caused by Bone Marrow Inflammation
Bone marrow inflammation, also known as myelitis, can cause significant damage to the hematopoietic system. Some of the potential damages include:
- Increased proliferation, DNA damage, and cell death (i.e., apoptosis, pyroptosis, and necroptosis) in hematopoietic cells 2
- Premature loss of hematopoiesis function, particularly in individuals with inherited bone marrow failure syndromes or immune-mediated aplastic anemia 2
- Damage to hematopoietic stem and progenitor cells (HSPCs), leading to bone marrow failure or leukemia 3, 4, 5
- Disruption of the bone marrow microenvironment, leading to clonal selection and potentially malignant transformation 5, 6
- Production of reactive oxygen species (ROS), which can damage DNA and lead to the transformation of HSCs into cancerous cells 4
Effects on Hematopoiesis
Chronic inflammation can have detrimental effects on hematopoiesis, leading to:
- Emergency myelopoiesis, where HSCs transition from quiescence to active division and differentiation 3, 4
- Increased activation, proliferation, and differentiation of HSCs, leading to the generation and activation of immune cells required to combat acute injury 4
- Damage to the HSC niche, leading to HSC depletion and bone marrow failure 4, 5
Association with Hematological Malignancies
Bone marrow inflammation has been linked to the development and progression of hematological malignancies, including:
- Leukemia, where inflammatory signals can lead to the transformation of HSCs into cancerous cells 4, 5
- Lymphoid malignancies, where inflammation can impact normal niches for hematopoietic progenitor cells and mature immune cells 6
- Myeloid malignancies, where inflammation can support the outgrowth and survival of malignant cells residing in the bone marrow niche 6