Differential Diagnosis for Enlarged Hypoechoic Lymph Node in Right Groin
Single Most Likely Diagnosis
- Metastatic malignancy: Given the location in the groin, a common site for lymph node metastasis from lower limb or pelvic malignancies, and the characteristics of the lymph node (enlarged, hypoechoic, increased cortical thickness), metastatic disease is a leading consideration. The size (1.9 x 1 cm) and description suggest a reactive or malignant process.
Other Likely Diagnoses
- Reactive lymphadenopathy: This could be due to infection, inflammation, or autoimmune diseases. The lymph node's reaction to a nearby infection or inflammation could explain its enlargement and altered echotexture.
- Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma can present with lymphadenopathy, and the groin is a possible location. The lymph nodes in lymphoma are often enlarged and may have a hypoechoic appearance.
Do Not Miss Diagnoses
- Tuberculosis (TB): Although less common in some regions, TB can cause lymphadenopathy that might appear similar on ultrasound. Missing TB could lead to significant morbidity if not treated promptly.
- Cat-scratch disease: Caused by Bartonella henselae, this condition can lead to lymphadenopathy, typically in the axilla or neck but potentially in the groin if the scratch is on the lower limb. It's crucial not to miss this diagnosis due to its specific treatment and potential for complications.
Rare Diagnoses
- Castleman disease: A rare disorder that involves an overgrowth of cells in the lymphatic system, which can cause lymphadenopathy. It's uncommon and might present with systemic symptoms in addition to localized lymph node enlargement.
- Kikuchi-Fujimoto disease: A rare, self-limiting condition that causes lymphadenopathy, typically in the neck but potentially elsewhere, including the groin. It's more common in young women and of Asian descent.
- Sarcoidosis: Although more commonly associated with pulmonary symptoms, sarcoidosis can cause lymphadenopathy. The groin is an uncommon location, but it should be considered in patients with known sarcoidosis or those presenting with systemic symptoms suggestive of the disease.