Streptococcal or Staphylococcal Infection: This is the most common cause of cervical adenitis, particularly in children. It is usually a result of a bacterial infection of the throat or skin that spreads to the lymph nodes in the neck.

Viral Upper Respiratory Infection: Viruses such as influenza, adenovirus, and enterovirus can cause cervical adenitis, often as part of a broader upper respiratory infection.
Tuberculosis (TB): Although less common in some regions, TB is a significant cause of cervical adenitis, especially in areas with high TB prevalence or in immunocompromised individuals.
Cat-Scratch Disease: Caused by Bartonella henselae, this infection is transmitted through cat scratches or bites and can lead to cervical adenitis.

Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma can present with cervical adenitis. Missing this diagnosis could lead to delayed treatment of a potentially life-threatening condition.
Metastatic Cancer: Cervical adenitis can be a sign of metastasis from various cancers, including head and neck cancers, lung cancer, and others. Early detection is crucial for treatment and prognosis.
Sarcoidosis: Although rare, sarcoidosis can cause cervical adenitis and is important to consider, especially in patients with other systemic symptoms or findings suggestive of sarcoidosis.

Toxoplasmosis: Typically seen in immunocompromised patients, toxoplasmosis can cause cervical adenitis.
Actinomycosis: A rare bacterial infection that can cause chronic cervical adenitis, often associated with dental procedures, oral surgery, or other forms of trauma to the mouth.
Brucellosis: A zoonotic infection that can cause cervical adenitis, among other symptoms, usually acquired through contact with infected animals or their products.
Histoplasmosis: A fungal infection that can cause cervical adenitis, particularly in individuals who have been exposed to bird or bat droppings.