Differential Diagnosis of Abnormal Lymph Node Enlargement in a 3-Year-Old Male
Single Most Likely Diagnosis
- Infectious lymphadenitis: This is the most common cause of lymph node enlargement in children, often due to viral or bacterial infections such as streptococcal pharyngitis, mononucleosis, or cat-scratch disease. The age and presentation of the child make this a highly plausible diagnosis.
Other Likely Diagnoses
- Reactive lymphadenopathy: This condition occurs in response to a nearby infection or inflammation, which could be due to a variety of common childhood illnesses.
- Tuberculosis (TB): Although less common in some regions, TB remains a significant concern globally and can cause lymphadenopathy, especially in children exposed to TB or in areas with high TB prevalence.
- Autoimmune disorders: Conditions like juvenile idiopathic arthritis (JIA) or systemic lupus erythematosus (SLE) can present with lymphadenopathy among other systemic symptoms.
Do Not Miss Diagnoses
- Lymphoma: Although less common, lymphomas such as Hodgkin lymphoma or non-Hodgkin lymphoma are critical to diagnose early due to their significant impact on prognosis and treatment. They can present with painless lymphadenopathy.
- Leukemia: Acute lymphoblastic leukemia (ALL) is the most common childhood cancer and can cause lymphadenopathy, among other symptoms like pallor, fatigue, and petechiae.
- Neuroblastoma: This is a pediatric cancer that can cause lymphadenopathy, especially if it metastasizes to lymph nodes. It often presents with a mass in the abdomen or neck.
Rare Diagnoses
- Castleman disease: A rare disorder that involves an overgrowth of cells in the lymph nodes, which can cause lymphadenopathy.
- Kikuchi-Fujimoto disease: A rare, self-limiting condition that causes lymphadenopathy, typically in the neck, and is often accompanied by fever and night sweats.
- Lymphangiomatosis: A rare condition characterized by the abnormal growth of lymphatic vessels, which can lead to lymphadenopathy among other symptoms.
- Histocytosis: A group of rare diseases involving abnormal proliferation of histiocytes, which can cause lymphadenopathy, among other systemic symptoms.