Multiple myeloma is a cancer affecting plasma cells, a type of white blood cell in the bone marrow responsible for producing antibodies. The disease itself and its therapies render patients highly susceptible to infections. This heightened vulnerability is a leading cause of complications, making it important to understand the risks involved.
Why Multiple Myeloma Increases Infection Risk
The heightened risk of infection in multiple myeloma stems from both the disease and its treatments. The cancer disrupts normal immune function by overwhelming the bone marrow with malignant plasma cells. These cancerous cells crowd out their healthy counterparts, leading to a significant drop in the production of functional antibodies necessary to fight off pathogens.
This process results in hypogammaglobulinemia, where the diversity of antibodies is severely limited. The malignant cells produce vast quantities of a single, non-functional antibody called a monoclonal protein, or M-protein. This M-protein is ineffective at combating infections, leaving the body’s defenses compromised against new bacterial or viral threats.
Compounding this immunodeficiency is the impact of various treatments. Therapies such as chemotherapy, immunomodulatory drugs, and steroids destroy cancer cells but also suppress the overall immune system. These treatments can reduce the counts of immune cells, including neutrophils and lymphocytes, weakening the body’s ability to fend off invaders. For patients undergoing a stem cell transplant, the preparatory high-dose chemotherapy eliminates the immune system for a period, creating a window of extreme vulnerability.
Common Types of Infections
Patients with multiple myeloma are particularly prone to certain types of infections. Bacterial infections are a primary concern, with the respiratory and urinary tracts being the most frequent sites of invasion. Pneumonia is especially common and can be severe, while urinary tract infections (UTIs) also occur with regularity. The risk of these localized infections escalating to a more dangerous systemic condition like sepsis, or blood poisoning, is a serious threat.
Viral infections also pose a significant danger. The influenza virus can lead to serious complications in individuals with weakened immunity. Another common viral threat is the reactivation of the varicella-zoster virus, which causes chickenpox, re-emerging as shingles. Viruses like COVID-19 also represent a substantial risk, as the suppressed immune system struggles to control viral replication.
Warning Signs of an Infection
Recognizing the early signs of an infection is important for anyone with multiple myeloma. Due to the suppressed immune response, some classic symptoms may be less pronounced, making it necessary for patients and their caregivers to be vigilant. A fever, even a low-grade one, or the presence of chills should always be reported to a healthcare provider without delay.
Other warning signs are specific to the location of the infection. A persistent cough, shortness of breath, or a sore throat can signal a respiratory infection like pneumonia. Pain or a burning sensation during urination is a symptom of a UTI. Any new areas of pain, redness, or swelling on the skin could indicate a skin infection, while diarrhea or vomiting may point to a gastrointestinal issue.
It is also important to be aware of more general symptoms. Unusual levels of fatigue that are beyond the baseline tiredness associated with the cancer or its treatment can be a red flag. Any new or unexplained confusion or change in mental state should be considered a serious sign that requires immediate medical evaluation.
Strategies for Prevention and Treatment
A proactive approach is fundamental to managing infection risk. Prevention begins with routine vaccinations, including the annual flu shot and vaccines against pneumonia. Doctors may prescribe prophylactic, or preventative, antibiotics or antiviral medications, particularly during periods of intense treatment. For patients with severely low antibody levels, intravenous immunoglobulin (IVIG) therapy can provide a temporary boost of functional antibodies.
Good hygiene practices are an effective way to reduce exposure to germs. Frequent and thorough hand washing is highly recommended, especially before eating and after being in public places. Patients may also be advised to avoid large crowds and close contact with individuals who are sick.
Should an infection occur, prompt treatment is necessary. When an infection is suspected, physicians will run tests, such as blood cultures, urine analyses, or imaging scans, to identify the specific pathogen. Once the cause is known, treatment is tailored accordingly. Bacterial infections are managed with antibiotics, and viral infections are treated with specific antiviral medications.