Differential Diagnosis for Swollen Lymph Nodes and Flank Pain
Single Most Likely Diagnosis
- Lymphoma: This is a type of cancer that begins in cells of the lymph system, which is part of the immune system. The presence of swollen lymph nodes in two distinct areas (groin and neck) along with flank pain could indicate a systemic disease like lymphoma, which often presents with lymphadenopathy (enlarged lymph nodes) and can cause pain due to organ involvement or compression.
Other Likely Diagnoses
- Tuberculosis (TB): TB can cause lymphadenopathy and systemic symptoms. The flank pain could be related to renal involvement, as TB can affect the kidneys.
- Infectious Mononucleosis: Caused by the Epstein-Barr virus, this condition can lead to swollen lymph nodes, fever, and fatigue. Flank pain might be due to splenomegaly (enlarged spleen) or less commonly, kidney involvement.
- HIV Infection: Early stages of HIV infection can present with lymphadenopathy and various systemic symptoms, including pain. The immune system suppression can lead to a variety of opportunistic infections that might cause flank pain.
Do Not Miss Diagnoses
- Testicular Cancer with Metastasis: Although less common, testicular cancer can metastasize to lymph nodes in the groin and neck. The flank pain could be due to retroperitoneal lymph node involvement.
- Renal Cell Carcinoma: This type of kidney cancer can cause flank pain and, in advanced stages, metastasize to lymph nodes.
- Syphilis: In its secondary stage, syphilis can cause lymphadenopathy and a wide range of systemic symptoms. It's crucial to consider syphilis due to its potential for serious complications if left untreated.
Rare Diagnoses
- Castleman Disease: A rare disorder that involves an overgrowth of cells in the lymphatic system, which can cause lymphadenopathy and systemic symptoms.
- Kikuchi-Fujimoto Disease: A rare, self-limiting condition that causes lymphadenopathy, typically in the neck, and can be accompanied by systemic symptoms.
- Whipple's Disease: A rare, systemic bacterial infection that can cause lymphadenopathy, among other symptoms, due to malabsorption and systemic infection.
Each of these diagnoses has a different level of likelihood based on the combination of symptoms presented (swollen lymph nodes in the groin and neck, along with flank pain). A thorough diagnostic workup, including imaging studies, blood tests, and potentially biopsies, would be necessary to determine the underlying cause.