Enlargement of Lymph Nodes and Spleen¶
Chapter 70 | Part 2: Cardinal Manifestations and Presentation of Diseases
KEY CLINICAL POINTS¶
- Lymphadenopathy is common in primary care, with >90% of cases being benign (e.g., infections, reactive processes) vs. <1% malignant.
- Splenomegaly is often associated with systemic diseases (e.g., infections, autoimmune disorders, malignancies).
- Biopsy is indicated for abnormal nodes (>2 cm, hard, fixed, or suspicious for malignancy) or when reactive causes are excluded.
- Post-splenectomy patients require pneumococcal and meningococcal vaccines due to increased infection risk.
- Massive splenomegaly (>8 cm below left costal margin) is most commonly due to lymphoma, leukemia, or myeloproliferative disorders.
1. DEFINITION & OVERVIEW¶
Lymphadenopathy refers to enlarged lymph nodes, which may be incidental or a presenting symptom. Splenomegaly is abnormal spleen enlargement, often indicating systemic disease. Lymph nodes are critical in immune response, while the spleen filters blood and stores red blood cells.
Table 70-1: Diseases Associated with Lymphadenopathy¶
| Category | Diseases |
|---|---|
| Infectious | Viral (EBV, CMV, HIV), Bacterial (TB, syphilis), Fungal (histoplasmosis), Parasitic (toxoplasmosis) |
| Immunologic | SLE, rheumatoid arthritis, IgG4-related disease |
| Malignant | Hodgkin’s lymphoma, NHL, metastatic cancer |
| Lipid Storage | Gaucher’s, Niemann-Pick |
| Endocrine | Hyperthyroidism |
| Other | Castleman’s disease, sarcoidosis, Kikuchi’s disease |
Table 70-2: Diseases Associated with Splenomegaly¶
| Mechanism | Diseases |
|---|---|
| Increased demand | Hereditary spherocytosis, thalassemia, infectious mononucleosis |
| Passive congestion | Cirrhosis, portal hypertension, congestive heart failure |
| Mechanism | Diseases |
|---|---|
| Infiltration | Lymphoma, metastatic cancer, Gaucher’s disease |
| Unknown | Idiopathic splenomegaly, Berylliosis |
1.1 Lymphadenopathy¶
Lymph nodes are secondary lymphoid organs; enlargement may reflect infection, inflammation, or malignancy. Nodes <1 cm are typically benign, while >2 cm may suggest malignancy.
1.2 Splenomegaly¶
The spleen filters blood, removes old RBCs, and stores platelets. Enlargement may result from increased demand (e.g., hemolysis), passive congestion, or infiltration by disease.
2. EPIDEMIOLOGY¶
Lymphadenopathy is common in primary care (2/3 cases benign, <1% malignant). Splenomegaly is less common but often indicates systemic disease. Age-related risk: benign causes predominate <50 years, malignant causes increase >50 years.
2.1 Lymphadenopathy¶
Most common causes: viral infections (e.g., EBV, CMV), bacterial infections (e.g., strep, TB), and reactive processes. Malignancy accounts for <1% of cases.
2.2 Splenomegaly¶
Incidence varies by region; common in tropical areas (e.g., 60% in New Guinea). Often associated with systemic diseases (e.g., malaria, TB, autoimmune disorders).
3. ETIOLOGY & PATHOPHYSIOLOGY¶
Lymphadenopathy arises from immune activation, infection, or malignancy. Splenomegaly results from increased demand (e.g., hemolysis), passive congestion, or infiltration by disease. Pathogenesis involves immune cell proliferation, inflammatory cytokines, or tumor infiltration.
3.1 Lymphadenopathy¶
Infections (viral, bacterial, fungal) trigger immune activation. Malignancies (lymphoma, leukemia) cause uncontrolled proliferation. Autoimmune diseases (SLE, rheumatoid arthritis) lead to chronic inflammation.
3.2 Splenomegaly¶
Increased demand: hemolysis (e.g., hereditary spherocytosis) or immune activation. Passive congestion: portal hypertension (cirrhosis). Infiltration: tumors (lymphoma, metastases), storage diseases (Gaucher’s), or infections (TB).
4. CLINICAL FEATURES¶
Lymphadenopathy may be painless or tender, with size and texture indicating etiology. Splenomegaly presents with LUQ discomfort, early satiety, or pain from infarction. Physical exam findings include palpable spleen, tender nodes, or signs of systemic illness.
4.1 Lymphadenopathy¶
Symptoms: fever, weight loss, night sweats. Signs: tender vs. nontender nodes, localized vs. generalized involvement. Size >2 cm or hard texture raises suspicion for malignancy.
4.2 Splenomegaly¶
Symptoms: LUQ pain, early satiety. Signs: palpable spleen, fullness on inspiration, venous hum. Complications: rupture, hypersplenism (cytopenias).
5. DIFFERENTIAL DIAGNOSIS¶
Lymphadenopathy: infectious (mononucleosis, TB), autoimmune (SLE), malignancy (lymphoma, metastases). Splenomegaly: infections (malaria, TB), storage diseases (Gaucher’s), myeloproliferative disorders, or systemic diseases (SLE, cirrhosis).
5.1 Lymphadenopathy¶
Benign: viral infections, reactive hyperplasia. Malignant: lymphoma, leukemia, metastases. Autoimmune: SLE, rheumatoid arthritis.
5.2 Splenomegaly¶
Infectious: malaria, TB. Storage diseases: Gaucher’s, Niemann-Pick. Malignancies: lymphoma, leukemia. Congestive: cirrhosis, heart failure.
6. INVESTIGATIONS & DIAGNOSIS¶
Diagnostic approach includes history, physical exam, imaging (ultrasound, CT), and biopsy. Laboratory tests include CBC, serology, and imaging for staging.
6.1 Laboratory Tests¶
CBC (cytopenias in hypersplenism), serology (EBV, CMV, HIV), and inflammatory markers. Coagulation studies may be needed for bleeding risk.
6.2 Imaging¶
Ultrasound (first-line for spleen size), CT/MRI for staging. Lymph node biopsy for definitive diagnosis of malignancy.
7. MANAGEMENT & TREATMENT¶
Management depends on etiology: antibiotics for infections, splenectomy for massive splenomegaly, and chemotherapy for malignancies. Post-splenectomy prophylaxis includes vaccines and infection monitoring.
7.1 Lymphadenopathy¶
Antibiotics for bacterial infections. Biopsy for suspicious nodes. Chemotherapy for lymphoma or leukemia. Monitoring for autoimmune diseases.
7.2 Splenomegaly¶
Splenectomy for hypersplenism or rupture. Management of underlying disease (e.g., TB, SLE). Vaccination for post-splenectomy patients.
8. PROGNOSIS & COMPLICATIONS¶
Prognosis varies by etiology. Complications include sepsis (post-splenectomy), splenic rupture, and hypersplenism. Early diagnosis and treatment improve outcomes.
8.1 Lymphadenopathy¶
Benign causes have excellent prognosis. Malignancies require prompt treatment. Autoimmune diseases may progress to systemic involvement.
8.2 Splenomegaly¶
Complications: splenic rupture, sepsis, hypersplenism. Prognosis depends on underlying disease (e.g., CML vs. lymphoma).
9. SPECIAL CONSIDERATIONS¶
Pediatric patients often have reactive lymphadenopathy. Elderly patients may have higher malignancy risk. Pregnancy requires careful evaluation for splenomegaly or lymphadenopathy.
9.1 Pediatrics¶
Benign causes (viral infections) are common. Watch for signs of malignancy in older children.
9.2 Pregnancy¶
Splenomegaly may be due to infections (e.g., malaria) or autoimmune diseases. Avoid splenectomy unless necessary.
10. KEY POINTS & CLINICAL PEARLS¶
- Lymphadenopathy is often benign; biopsy is indicated for suspicious nodes.
- Splenomegaly is a red flag for systemic disease.
- Post-splenectomy patients require vaccines and prompt infection evaluation.
- Ultrasound is the first-line tool for spleen size assessment.
- Massive splenomegaly (>8 cm) is most commonly due to lymphoma or leukemia.