Can bone marrow in a bone go bad?

Bone marrow is a soft, gelatinous tissue found inside bones. It contains hematopoietic stem cells that can differentiate into red blood cells, white blood cells, and platelets. Bone marrow also contains adipose tissue and stromal cells that provide structural and functional support.

The lifespan of bone marrow cells varies. Red blood cells live for about 120 days, platelets for about 10 days, and white blood cells for just hours to days. This constant turnover means bone marrow is very metabolically active and requires an abundant blood supply.

So can bone marrow “go bad” and if so, how?

What happens when bone marrow goes bad?

There are a few ways bone marrow can go bad:

Infection

Like any tissue in the body, bone marrow is susceptible to infection. Bacteria, viruses, or fungi can enter the bone and infect the marrow. This is known as osteomyelitis and can be difficult to treat since the infection is walled off inside the bone. Symptoms include bone pain, fever, and fatigue. Without treatment, the infection can destroy bone marrow leading to low blood counts.

Bone marrow failure disorders

There are genetic disorders that disrupt the normal production of blood cells in the bone marrow. These bone marrow failure syndromes include aplastic anemia, myelodysplastic syndromes (MDS), and paroxysmal nocturnal hemoglobinuria (PNH). The marrow stops making enough healthy blood cells, leading to low counts and increased risk of bleeding and infection. Bone marrow transplantation may be required to replace the diseased marrow.

Leukemia

Leukemia is a blood cancer arising from white blood cells produced in the bone marrow. When bone marrow contains too many abnormal white blood cells, they crowd out the healthy cells. This leads to low red cell, platelet, and normal white cell counts. Without treatment, leukemia can be fatal as the body can no longer make enough functional blood cells. Chemotherapy is used to try to kill the cancerous cells and allow healthy marrow to regrow.

Multiple myeloma

Multiple myeloma is a cancer involving plasma cells, a type of white blood cell made in bone marrow. In multiple myeloma, plasma cells proliferate uncontrollably and produce abnormal proteins that accumulate in the blood and urine. The cancerous plasma cells crowd out normal white and red blood cell production leading to anemia and immune problems. Multiple myeloma also causes lytic bone lesions as the malignant cells dissolve bone mineral. Treatment includes chemotherapy, immunotherapy, and stem cell transplants.

Metastatic cancer

Sometimes cancers originating in other parts of the body, like breast or prostate cancer, can metastasize to the bone marrow. This is referred to as bone metastasis. The cancer cells disrupt normal marrow function and impact blood cell counts. They also stimulate osteoclasts leading to bone destruction. Metastases may be treated with chemotherapy, radiation, or surgery.

What causes bone marrow to go bad?

There are several potential causes for unhealthy or dysfunctional bone marrow:

Genetic mutations

Many bone marrow failure syndromes and blood cancers are caused by acquired genetic mutations or inherited genetic disorders. These mutations disrupt normal cell growth, death and function. For example, a mutation in the RB1 tumor suppressor gene can lead to retinoblastoma cancer which can spread to bone marrow.

Toxins

Exposure to chemicals like benzene or radiation can damage stem cells and lead to marrow problems like aplastic anemia. Cancer treatments like chemotherapy and radiation can also impair bone marrow function in the short-term. However, this is usually reversible once treatment is completed.

Autoimmune disorders

In some autoimmune diseases, the body’s immune system mistakenly attacks blood cells made in the bone marrow. For example, in immune thrombocytopenia (ITP), the immune system destroys platelets. In aplastic anemia, white blood cells called T-cells attack the marrow, causing severe pancytopenia.

Infections

Viruses like hepatitis C, HIV, and Epstein-Barr virus (EBV) can infect marrow cells. Parvovirus B19 is known to infect red blood cell precursors. These infections disrupt normal hematopoiesis and blood cell production.

Unknown causes

In other cases, bone marrow failure occurs for unknown reasons. The body’s microenvironment and supporting stromal cells may become damaged or defective, impairing marrow function. The cause in these cases is often not identified.

Risk factors

Certain factors can increase the risk of bone marrow problems:

Genetic disorders

People born with inherited disorders like Fanconi anemia, dyskeratosis congenita, or Diamond-Blackfan anemia have abnormal marrow function.

Chemical exposure

Working with chemicals like pesticides, benzene, or taking certain medications can be toxic to bone marrow. Chemotherapy used to treat cancers also damages marrow.

Radiation exposure

People exposed to radiation through nuclear accidents, medical radiation or radiation therapy have a higher risk of marrow problems.

Viruses

HIV, hepatitis C, EBV and parvovirus infection can lead to low blood cell counts by infecting marrow cells.

Age

As people age, bone marrow becomes less efficient at producing blood cells. Older adults are more prone to anemia, MDS and other marrow disorders.

Autoimmune disorders

Having an overactive immune system that attacks the body’s own tissues puts people at risk of low blood counts.

Cancer

Those with a history of cancers, like lymphoma or breast cancer, have a higher chance of metastasis to the bone marrow.

Signs bone marrow may be unhealthy

There are some signs that can indicate a person’s bone marrow is not functioning properly:

Anemia

Anemia, meaning low red blood cell counts, commonly results from poor marrow function. This causes fatigue, weakness, pale skin and shortness of breath.

Low white blood cell count

A low white blood cell count is called leukopenia. White blood cells fight infection so leukopenia impairs the immune system.

Low platelet count

Thrombocytopenia refers to a low platelet count. Platelets help blood clot, so low levels cause easy bruising and bleeding.

Bone pain

Marrow disorders like leukemia can cause bone pain as the marrow expands or is injured by cancer cells.

Frequent infections

With reduced white blood cells from unhealthy marrow, infections become more common and severe.

Fatigue

Anemia and low blood counts lead to excessive fatigue, weakness and shortness of breath.

Bleeding problems

Low platelets mean blood doesn’t clot well. Nosebleeds, bleeding gums, scattered bruises and heavy periods can result.

Bone fractures

Cancer like multiple myeloma weakens bones and makes them more prone to fractures.

Diagnosing unhealthy bone marrow

If signs of marrow problems are present, doctors use several tests to evaluate bone marrow function:

Blood tests

A complete blood count (CBC) measures red and white blood cell and platelet counts. Blood chemistry tests assess kidney and liver function, proteins and enzymes. These can detect anemia, infection, or cancer activity.

Bone marrow biopsy

A core sample of actual bone marrow is extracted usually from the hip bone. The sample is examined under a microscope to evaluate cellularity and look for abnormalities.

Cytogenetic testing

chromosomes of marrow cells are analyzed for genetic mutations that could indicate MDS, leukemia or other bone marrow disorders.

Imaging tests

X-rays, CT scans or PET scans of bones can detect fractures, lytic lesions, or bone tumors indicating metastatic cancer.

Blood cultures

Blood is tested to see if bacteria or fungus is present indicating infection in the bone or marrow.

Treating unhealthy bone marrow

The treatment for unhealthy bone marrow depends on the specific diagnosis:

Antibiotics for infection

Intravenous antibiotics are used to treat osteomyelitis and clear infection from the bone and marrow. Long courses lasting several weeks may be needed.

Chemotherapy

For blood cancers like leukemia, intensive chemotherapy is used to kill abnormal cells in the marrow. This allows normal cells to regrow.

Immunosuppressants

Drugs that suppress the immune system may be used to treat marrow dysfunction caused by autoimmune disorders.

Blood transfusions

If blood counts are very low, transfusions can temporarily help supplement red blood cells and platelets.

Growth factors

Medications like erythropoietin and GM-CSF stimulate bone marrow to produce more blood cells.

Stem cell transplant

For severe marrow failure, transplantation of healthy bone marrow stem cells can repopulate the marrow and allow normal blood cell production.

Supportive care

Until marrow recovers, patients may need IV fluids and electrolytes, pain management, and medication to prevent infections.

Prognosis

The prognosis for unhealthy bone marrow depends on the specifics of the condition:

Cancer

Leukemia, myeloma and other marrow cancers have improved survival rates with modern treatments but are often difficult to cure entirely.

Marrow failure disorders

Inherited conditions like Fanconi anemia have no cure currently. Supportive care and transplant can prolong life but outcomes vary.

Aplastic anemia

Survival is good if enough marrow function returns. 10-year survival is 60-80% with treatment, or 20-30% without.

Acquired marrow problems

Marrow toxicity from chemicals, radiation or infections often resolves if the exposure is removed and marrow recovers over time.

Osteomyelitis

Bone infections can be cured with prompt, aggressive antibiotic therapy lasting weeks to months.

Overall, unhealthy bone marrow left unchecked and untreated can be life-threatening. But diagnosis and management by a hematologist and oncologist provide the best chance for recovery of normal marrow function.

Prevention

Some ways to help prevent bone marrow problems include:

Avoid toxins

Limit exposure to chemicals like pesticides and benzene that are toxic to marrow. Take appropriate safety precautions when working with hazardous substances.

Practice safe habits

Be aware of activities that pose radiation risk and follow safety guidelines, like using sunblock outside. Get recommended cancer screenings to detect leukemia early.

Eat healthy

Consume a balanced diet rich in vitamins and minerals needed for good marrow function, like vitamin B12, folate, iron and selenium.

Exercise

Regular physical activity keeps bones and marrow healthy. Weight-bearing activities promote bone strength.

Don’t smoke

Avoid tobacco as it contains carcinogens that damage cells. Smoking raises the risk of MDS and leukemia.

Treat underlying conditions

Properly manage any medical conditions you have, like autoimmune disorders or hepatitis C, that could affect marrow.

Get vaccines

Immunizations help prevent infections from bacteria or viruses that could spread to bone marrow. Get an annual flu shot.

See your doctor

Have regular wellness visits for evaluation of blood cell counts. Report any fatigue, infections or other concerning symptoms promptly.

While bone marrow problems aren’t always preventable, following healthy lifestyle practices can help keep your marrow in good working order. Consult your doctor if you have any concerns.

Conclusion

Bone marrow is susceptible to a number of disorders that can impair its ability to properly produce blood cells. These include cancers like leukemia, immune conditions, genetic abnormalities, infections, and toxic exposures. Symptoms of unhealthy marrow include fatigue, frequent infections, and problems with bleeding or bruising. Tests like bloodwork, bone marrow biopsy and cytogenetic analysis help diagnose marrow disorders. Treatments vary based on the specific illness but may include antibiotics, chemotherapy, radiation, medications and stem cell transplant. If caught early, many marrow problems can be successfully managed. Practicing healthy habits is important to try to prevent bone marrow dysfunction. Being aware of your body and reporting any concerning symptoms to your doctor allows for prompt evaluation and treatment if your bone marrow does “go bad”. With close follow-up and care from a hematologist, outcomes can be optimized.

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