Hello and welcome to HCM,
An inguinal swelling occurs most commonly due to lymph node enlargement.
The blue-black discoloration of the overlying skin with a black circular lesion can be due to infection or some kind of skin lesion.
An aspiration cytology of the lesion is required.
This investigation will sample the cells of the lesion.
The cells are stained and examined microscopically.
The origin and character of the lesion can be determined by examining the cells of the lesion.
Lymph node enlargement can occur due to inflammation,
lymphoma or a
melanoma as suggested by black discoloration of the skin.
Malignancy is accompanied by weakness, loss of appetite, and
weight loss.
A preceding history of infection of the
urinary tract, lower limb can cause inflammatory enlargement of the inguinal lymph nodes.
Thanks and take care
Dr Shailja P Wahal