Bone marrow suppression also known as myelotoxicity or myelosuppression, is the decrease in production of cells responsible for providing immunity ( leukocytes), carrying oxygen (

erythrocytes Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...

), and/or those responsible for normal blood clotting (

thrombocytes Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ini ...

Bone marrow Bone marrow is a semi-solid tissue found within the spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of hematopoietic ...

suppression is a serious

side effect In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...

chemotherapy Chemotherapy (often abbreviated to chemo and sometimes CTX or CTx) is a type of cancer treatment that uses one or more anti-cancer drugs ( chemotherapeutic agents or alkylating agents) as part of a standardized chemotherapy regimen. Chemother ...

and certain drugs affecting the

immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splint ...

such as

azathioprine Azathioprine (AZA), sold under the brand name Imuran, among others, is an immunosuppressive medication. It is used in rheumatoid arthritis, granulomatosis with polyangiitis, Crohn's disease, ulcerative colitis, and systemic lupus erythematosu ...

. The risk is especially high in cytotoxic chemotherapy for

leukemia Leukemia ( also spelled leukaemia and pronounced ) is a group of blood cancers that usually begin in the bone marrow and result in high numbers of abnormal blood cells. These blood cells are not fully developed and are called ''blasts'' or ...

Nonsteroidal anti-inflammatory drug Non-steroidal anti-inflammatory drugs (NSAID) are members of a therapeutic drug class which reduces pain, decreases inflammation, decreases fever, and prevents blood clots. Side effects depend on the specific drug, its dose and duration of ...

s (NSAIDs), in some rare instances, may also cause bone marrow suppression. The decrease in blood cell counts does not occur right at the start of chemotherapy because the drugs do not destroy the cells already in the bloodstream (these are not dividing rapidly). Instead, the drugs affect new blood cells that are being made by the bone marrow. When myelosuppression is severe, it is called myeloablation. Many other drugs including common antibiotics may cause bone marrow suppression. Unlike chemotherapy the effects may not be due to direct destruction of stem cells but the results may be equally serious. The treatment may mirror that of chemotherapy-induced myelosuppression or may be to change to an alternate drug or to temporarily suspend treatment. Because the bone marrow is the manufacturing center of blood cells, the suppression of bone marrow activity causes a deficiency of blood cells. This condition can rapidly lead to life-threatening

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dise ...

, as the body cannot produce leukocytes in response to invading bacteria and

viruses A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's ...

, as well as leading to

anaemia Anemia or anaemia ( British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, ...

due to a lack of

red blood cells Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...

and spontaneous severe bleeding due to deficiency of

platelets Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby ini ...

Parvovirus B19 Primate erythroparvovirus 1, generally referred to as B19 virus (B19V), parvovirus B19 or sometimes erythrovirus B19, is the first (and until 2005 the only) known human virus in the family ''Parvoviridae'', genus ''Erythroparvovirus''; it measur ...

inhibits

erythropoiesis Erythropoiesis (from Greek 'erythro' meaning "red" and 'poiesis' "to make") is the process which produces red blood cells (erythrocytes), which is the development from erythropoietic stem cell to mature red blood cell. It is stimulated by decrea ...

by lytically infecting RBC precursors in the bone marrow and is associated with a number of different diseases ranging from benign to severe. In

immunocompromised Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that a ...

patients, B19 infection may persist for months, leading to chronic

anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, ...

with B19 viremia due to chronic marrow suppression.

Treatment

Bone marrow suppression due to

can be treated by changing to another medication such as

mycophenolate mofetil Mycophenolic acid (MPA) is an immunosuppressant medication used to prevent rejection following organ transplantation and to treat autoimmune conditions such as Crohn's disease and lupus. Specifically it is used following kidney, heart, and ...

(for organ transplants) or other disease-modifying drugs in

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are invol ...

Crohn's disease Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea (which may be bloody if inflammation is severe), fever, abdominal distension, ...

Chemotherapy induced myelosuppression

Bone marrow suppression due to anti-cancer chemotherapy is much harder to treat and often involves hospital admission, strict infection control, and aggressive use of intravenous

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...

at the first sign of infection. G-CSF is used clinically (see

Neutropenia Neutropenia is an abnormally low concentration of neutrophils (a type of white blood cell) in the blood. Neutrophils make up the majority of circulating white blood cells and serve as the primary defense against infections by destroying bacteri ...

) but tests in mice suggest it may lead to bone loss."Researchers urge monitoring of bone health during chemotherapy"
GM-CSF has been compared to G-CSF as a treatment of chemotherapy-induced myelosuppression/

. Trilaciclib (COSELA), a CDK4/6 inhibitor, is administered before

small cell lung cancer Small-cell carcinoma is a type of highly malignant cancer that most commonly arises within the lung, although it can occasionally arise in other body sites, such as the cervix, prostate, and gastrointestinal tract. Compared to non-small cell car ...

to control chemotherapy-induced myelosuppression.

Research

In developing new chemotherapeutics, the efficacy of the drug against the disease is often balanced against the likely level of myelotoxicity the drug will cause. In-vitro colony forming cell (CFC) assays using normal human bone marrow grown in appropriate semi-solid media such as ColonyGEL have been shown to be useful in predicting the level of clinical myelotoxicity a certain compound might cause if administered to humans.predicting-drug-induced-myelotoxicity
/ref> These predictive in-vitro assays reveal effects the administered compounds have on the bone marrow progenitor cells that produce the various mature cells in the blood and can be used to test the effects of single drugs or the effects of drugs administered in combination with others.

References

{{DEFAULTSORT:Bone Marrow Suppression Hematology Oncology

Treatment

Chemotherapy induced myelosuppression

Research

See also

References