Differential Diagnosis for Swollen Lymph Nodes, Fatigue, and Systemic Symptoms

The patient presents with a complex set of symptoms including slowly growing swollen lymph nodes over 3 years, recent acceleration of lymph node growth, fatigue, appetite loss, nausea, lightheadedness, and fever. Given the progression and combination of these symptoms, a comprehensive differential diagnosis is necessary.

• Single Most Likely Diagnosis (40%):

  • Lymphoma: The gradual enlargement of lymph nodes over years, recent acceleration, and systemic symptoms such as fatigue, appetite loss, nausea, and fever are highly suggestive of lymphoma. The presence of a left supraclavicular lymph node is particularly concerning for lymphoma.

• Other Likely Diagnoses (30%):

  • Chronic Infections (e.g., Tuberculosis): Although the patient did not respond to a week of antibiotics, chronic infections like TB can cause prolonged fever, weight loss, and lymphadenopathy. The normal initial LDH, CRP, and ESR do not rule out TB, as these can be normal in early or certain forms of the disease.
  • Autoimmune Disorders (e.g., Rheumatoid Arthritis, Lupus): These conditions can cause lymphadenopathy, fever, and systemic symptoms. However, the absence of joint symptoms or other specific findings for these diseases makes them less likely.
  • Chronic Lymphocytic Leukemia (CLL): CLL can present with lymphadenopathy and systemic symptoms, although it is more common in older adults.

• Do Not Miss Diagnoses (20%):

  • Hodgkin Lymphoma: Similar to non-Hodgkin lymphoma but often presents in younger individuals and can have a more favorable prognosis with early treatment. The left supraclavicular lymph node is particularly concerning for this diagnosis.
  • Metastatic Cancer: Although less likely given the age and gradual onset, certain cancers (like breast, lung, or stomach cancer) can metastasize to lymph nodes and cause systemic symptoms. The recent increase in symptoms could indicate progression of disease.
  • HIV/AIDS: Infection with HIV can lead to lymphadenopathy, systemic symptoms, and increased susceptibility to infections. Given the potential for severe consequences if missed, testing for HIV is crucial.

• Rare Diagnoses (10%):

  • Castleman Disease: A rare disorder that can cause lymphadenopathy, fever, and systemic symptoms. It is often associated with HIV infection but can occur in HIV-negative individuals.
  • Kikuchi-Fujimoto Disease: A rare, self-limiting condition that causes lymphadenopathy, fever, and night sweats, more common in young women.
  • Sarcoidosis: Although it can cause lymphadenopathy and systemic symptoms, the absence of respiratory symptoms or skin findings makes this less likely.

Justification

The differential diagnosis is based on the combination of chronic and acute symptoms presented by the patient. The key factors influencing the likelihood of each diagnosis include the duration and progression of lymphadenopathy, the presence of systemic symptoms such as fever and weight loss, and the lack of response to antibiotic treatment. Given the complexity and potential severity of these conditions, a thorough diagnostic workup including imaging studies, lymph node biopsy, and specific tests for infections and autoimmune disorders is essential.