Hi

Thanks for the query

The image you have posted seems to be an infected sebacious cyst. It is not possible for the pool water to infect the cyst; it could be just a co-incidence.

Sebaceous cysts are small bumps that develop beneath the skin on your face, neck, trunk, etc. They are usually slow-growing and often painless. They arise from the glands that secrete oily matter that lubricates hair and skin (sebaceous glands). As the collection inside the cyst increases it becomes tense and infected, sometimes it can burst out due to increased pressure.

For the time being, you can squeeze and remove the contents of the sac, and also keep the area clean. You can try taking some antibiotics such as amoxycillin or cefuroxime to control the infection. Consult your doctor for complete evaluation and excision of the same.

Hope I have answered your query; I will be available for the follow-up queries.

Regards
Dr. Naveen Kumar N.
ENT and Head & Neck Surgeon

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