NCLEX Review Guide: Multiple Myeloma

Definition & Pathophysiology

• Multiple myeloma is a malignant proliferation of plasma cells in the bone marrow that produces monoclonal immunoglobulins (M proteins). These abnormal plasma cells replace normal bone marrow elements and secrete paraproteins that can cause organ damage.
• The malignant plasma cells produce osteoclast activating factor (OAF), which stimulates osteoclasts to resorb bone, leading to hypercalcemia and pathologic fractures.

Risk Factors & Epidemiology

• Multiple myeloma most commonly affects individuals over the age of 65, with median age at diagnosis being approximately 70 years. It is more common in men than women and has a higher incidence in African Americans.
• Risk factors include advanced age, male gender, African American race, family history, radiation exposure, and certain chemical exposures (benzene, pesticides).

Common Symptoms

• Bone pain (especially in the back and ribs) is the most common presenting symptom, affecting approximately 70% of patients. The pain is typically constant and exacerbated by movement due to lytic bone lesions.
• Patients often present with fatigue and weakness due to anemia, which results from the replacement of normal hematopoietic cells in the bone marrow by malignant plasma cells.
• Recurrent infections occur due to impaired humoral immunity and neutropenia, with pneumonia and pyelonephritis being particularly common.

Complications

• Hypercalcemia occurs in 30% of patients due to increased bone resorption and can lead to confusion, dehydration, constipation, and cardiac arrhythmias.
• Renal insufficiency develops in approximately 20-40% of patients due to multiple factors including light chain proteinuria (Bence Jones proteins), hypercalcemia, dehydration, and amyloidosis.
• Spinal cord compression is a medical emergency that requires immediate intervention to prevent permanent neurological damage. It presents with back pain, weakness, sensory loss, and bowel/bladder dysfunction.
• Hyperviscosity syndrome occurs when excessive amounts of M proteins increase blood viscosity, leading to visual disturbances, neurological symptoms, and bleeding tendencies.

Diagnostic Criteria

• The diagnosis of multiple myeloma requires the presence of ≥10% clonal plasma cells in the bone marrow OR a biopsy-proven plasmacytoma PLUS one or more of the CRAB features attributable to the plasma cell disorder.
• Updated criteria also include biomarkers of malignancy: ≥60% plasma cells in the bone marrow, serum free light chain ratio ≥100, or >1 focal lesion on MRI.

Laboratory & Diagnostic Tests

• Serum protein electrophoresis (SPEP) and immunofixation are essential for detecting and identifying monoclonal proteins. Approximately 80% of patients have an IgG or IgA monoclonal protein.
• Serum free light chain (FLC) assay measures kappa and lambda free light chains and calculates the kappa/lambda ratio. An abnormal ratio indicates clonal plasma cell proliferation.
• Complete blood count (CBC) typically shows normocytic, normochromic anemia in 70% of patients at diagnosis. Leukopenia and thrombocytopenia may be present in advanced disease.
• Comprehensive metabolic panel may reveal elevated creatinine (renal insufficiency), hypercalcemia, and occasionally elevated liver enzymes.
• Bone marrow aspiration and biopsy show increased plasma cells (≥10%), often with abnormal morphology.
• Imaging studies include skeletal survey (traditional), low-dose whole-body CT, MRI, or PET/CT to detect bone lesions.

Pharmacological Management

• Treatment typically involves combination therapy with proteasome inhibitors (bortezomib, carfilzomib), immunomodulatory drugs (lenalidomide, pomalidomide), and corticosteroids (dexamethasone).
• Newer agents include monoclonal antibodies (daratumumab, elotuzumab), histone deacetylase inhibitors (panobinostat), and BCL-2 inhibitors (venetoclax).
• Bisphosphonates (pamidronate, zoledronic acid) are used to prevent skeletal-related events by inhibiting osteoclast activity. These medications require monitoring for renal function and osteonecrosis of the jaw.

Procedural Interventions

• Autologous stem cell transplantation (ASCT) remains a standard of care for eligible patients, typically following induction therapy to reduce tumor burden. The procedure involves harvesting the patient's own stem cells, administering high-dose chemotherapy (usually melphalan), and then reinfusing the collected stem cells.
• Radiation therapy is used for painful bone lesions, impending pathologic fractures, or spinal cord compression. It provides effective pain relief in approximately 75-100% of patients.
• Vertebroplasty or kyphoplasty may be performed for painful vertebral compression fractures to stabilize the spine and relieve pain.

Autologous Stem Cell Transplantation Process

1. Mobilization of stem cells using growth factors (G-CSF) with or without chemotherapy
2. Collection of peripheral blood stem cells via apheresis
3. Administration of high-dose chemotherapy (conditioning regimen)
4. Reinfusion of collected stem cells
5. Supportive care during pancytopenia period
6. Engraftment and recovery phase

Supportive Care

• Hydration is crucial to prevent renal damage from hypercalcemia and light chain excretion. Patients should maintain fluid intake of at least 2-3 liters per day unless contraindicated.
• Pain management often requires a multimodal approach including analgesics, bisphosphonates, radiation therapy, and sometimes surgical intervention for pathologic fractures.
• Prophylactic antibiotics may be considered for patients with recurrent infections, particularly during periods of intensive chemotherapy.
• Erythropoiesis-stimulating agents may be used for symptomatic anemia if not contraindicated.
• Hypercalcemia management includes IV fluids, bisphosphonates, and sometimes calcitonin for severe cases.

Nursing Assessment

• Perform a comprehensive pain assessment using a standardized pain scale, documenting location, quality, intensity, aggravating/alleviating factors, and impact on function. Bone pain in multiple myeloma is typically constant and worsens with movement.
• Assess for signs and symptoms of hypercalcemia including confusion, lethargy, constipation, nausea, vomiting, polyuria, and cardiac abnormalities.
• Monitor for signs of spinal cord compression (back pain, weakness, numbness, bowel/bladder dysfunction) which requires immediate medical intervention.
• Evaluate for bleeding tendencies due to thrombocytopenia or coagulopathy related to paraproteinemia.
• Assess for signs of infection, as patients are immunocompromised due to disease and treatment effects.

Nursing Interventions

• Administer prescribed medications according to protocols, monitoring for side effects and drug interactions. Particular attention should be paid to chemotherapy agents, bisphosphonates, and analgesics.
• Promote adequate hydration to prevent renal damage from hypercalcemia and light chain excretion. Monitor intake and output, and encourage fluid intake of 2-3 liters daily unless contraindicated.
• Implement fall prevention strategies due to increased risk of pathologic fractures. This includes environmental modifications, assistive devices, and patient education.
• Provide infection prevention education, including hand hygiene, avoiding crowds and ill contacts, and recognizing early signs of infection.

Patient Education

• Educate patients about their disease process, treatment options, and potential side effects of therapy. Emphasize the importance of adherence to treatment regimens and follow-up appointments.
• Teach patients to recognize and report signs of infection promptly (fever, chills, cough, dysuria) due to their immunocompromised state.
• Provide instruction on safe mobility techniques to prevent fractures, including proper body mechanics and use of assistive devices as needed.
• Educate about the importance of adequate hydration and strategies to maintain fluid intake, especially during periods of hypercalcemia.
• Discuss nutritional needs, including adequate protein intake to support immune function and calcium/vitamin D for bone health if not contraindicated by hypercalcemia.

• Multiple myeloma is a malignant proliferation of plasma cells in the bone marrow characterized by the production of monoclonal proteins and the CRAB features (hypercalcemia, renal insufficiency, anemia, and bone lesions).
• Diagnosis requires ≥10% clonal plasma cells in bone marrow or a plasmacytoma plus evidence of end-organ damage attributable to the plasma cell disorder.
• Common presenting symptoms include bone pain (especially back pain), fatigue, recurrent infections, and symptoms related to hypercalcemia or renal insufficiency.
• Treatment approaches include combination therapy with proteasome inhibitors, immunomodulatory drugs, corticosteroids, and monoclonal antibodies, with autologous stem cell transplantation for eligible patients.
• Supportive care measures include bisphosphonates for bone disease, adequate hydration for renal protection, pain management, and infection prevention.
• Nursing care focuses on symptom management, prevention of complications, medication administration, and patient education.

Potential Areas of Confusion

• Multiple myeloma vs. bone metastases: Both can present with bone pain and lytic lesions on imaging. However, multiple myeloma shows distinctive "punched-out" lesions without sclerotic changes, monoclonal protein in serum/urine, and plasma cell infiltration in bone marrow.
• Light chain myeloma vs. primary amyloidosis: Both involve light chain production, but primary amyloidosis features amyloid deposits in tissues causing cardiomyopathy, nephrotic syndrome, and neuropathy, while light chain myeloma shows the typical CRAB features.
• Renal failure in multiple myeloma: Often confused with other causes of renal failure. In myeloma, it's primarily due to cast nephropathy from light chains, hypercalcemia, and dehydration, rather than direct tumor infiltration.

NCLEX Strategy Tips

• For questions about multiple myeloma, focus on the characteristic CRAB features and how they relate to the underlying pathophysiology.
• When answering questions about nursing priorities, remember that prevention of pathologic fractures, renal protection, and infection prevention are top priorities.
• For medication-related questions, understand the common side effects and nursing considerations for proteasome inhibitors (peripheral neuropathy), immunomodulatory drugs (thromboembolism risk), and bisphosphonates (renal toxicity, osteonecrosis of jaw).
• In questions about laboratory values, look for the classic triad of anemia, elevated total protein with decreased albumin (creating an "albumin gap"), and elevated creatinine.

Common Pitfalls

• Overlooking hypercalcemia symptoms: Remember that hypercalcemia can present with subtle neurological symptoms before progressing to more obvious manifestations. Early signs include confusion, lethargy, and constipation.
• Confusing treatment goals: Multiple myeloma treatment is typically not curative but aims for disease control. Don't select answer options that suggest complete cure as the expected outcome.
• Underestimating infection risk: Patients with multiple myeloma are at risk for infection due to both disease-related immunodeficiency and treatment effects. Infection prevention is a critical nursing priority.
• Focusing only on bone pain: While bone pain is common, renal complications are a major cause of morbidity and mortality. Questions may test your knowledge of renal protective measures.

Self-Assessment Checkpoints