Differential Diagnosis for a Left Neck Level 2 Nontender Mass in Pediatrics
Single Most Likely Diagnosis
- Reactive lymphadenopathy: This is the most common cause of a neck mass in children, often resulting from a viral upper respiratory infection. The fact that the mass is nontender and located in the neck, a common site for lymph nodes, supports this diagnosis.
Other Likely Diagnoses
- Tuberculosis (TB) lymphadenitis: Although less common, TB can cause lymphadenopathy, especially in endemic areas or in children with exposure history. The lack of tenderness does not rule out TB.
- Cat-scratch disease: Caused by Bartonella henselae, this condition can lead to lymphadenopathy, typically in the neck, after a cat scratch or bite. The absence of tenderness is consistent with this diagnosis.
- Mononucleosis: Infectious mononucleosis, caused by Epstein-Barr virus, can lead to lymphadenopathy, including in the neck. The nontender nature of the mass is compatible with this condition.
Do Not Miss Diagnoses
- Lymphoma: Although less common, lymphoma (Hodgkin or non-Hodgkin) can present with lymphadenopathy. It is crucial to consider this diagnosis due to its significant implications for treatment and prognosis.
- Metastatic disease: Certain cancers, such as neuroblastoma, rhabdomyosarcoma, or thyroid cancer, can metastasize to the lymph nodes in the neck. Early detection is vital for effective management.
- Toritcollis or congenital muscular torticollis with associated lymphadenopathy: While the primary issue is the muscular torticollis, associated lymphadenopathy can sometimes be the presenting feature.
Rare Diagnoses
- Branchial cleft cyst: A congenital anomaly that can present as a neck mass, typically along the anterior border of the sternocleidomastoid muscle. It is less common but should be considered in the differential diagnosis.
- Thyroglossal duct cyst: Another congenital anomaly that can present as a midline neck mass, although it can occasionally be off midline. It is a rare cause of a neck mass but is important to recognize.
- Kikuchi disease: A rare form of lymphadenitis, more common in Asian populations, which can mimic lymphoma or tuberculosis. It is self-limiting but can be diagnosed after excluding other more serious conditions.