Hello
Thanks for writing to us.

A palpable lump in the groin is most commonly caused by inguinal lymphadenopathy.
Depending on exact location a painful groin lump could be any of three general possibilities.

The first consideration is - lymph node. There is a cluster of lymph nodes in the groin which can become inflamed in response to some kind of infection. If you have any symptoms of infection in general including fever, pain with urination, or vaginal discharge this could trigger lymph node swelling.

Other causes include allergic reactions or some malignancy. So it is best to rule out STD’s(sexually transmitted disease) first and then move on to investigate other causes of swollen lymph node.
Since there is a good possibility of lymph node swelling we also need to know the size, number of lymph nodes along with its texture. We also need to check if it is on both sides. A lot of causes can be ruled out by physical examination of these lymph nodes.

The second possibility is that this could be a small infected sebaceous cyst. This is triggered by an ingrown hair which causes an infection and the infection progresses somewhat until pus accumulates under the skin. These can be quite painful and sometimes are treated with antibiotics or even a small procedure where the cyst is drained surgically.

The last possibility would be a hernia. These tend to be larger and are caused by a small weakness in the abdominal wall which allows for part of the bowels to push through creating a palpable lump.

You may get the initial physical examination, relevant tests and treatment done under care of your Physician.

I hope my answer and recommendations are adequate and helpful. Waiting for your further follow up queries if any.
Regards.

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