Brief Answer:
Some possible diagnoses and suggestions

Detailed Answer:
Hello,

Thank you for using Healthcaremagic to post your health query.
I read carefully your question and I understand your concern.

You will need a physical exam of the testicles so a local doctor can palpate and understand the consistency of them.
It is normal that one testicle is slightly larger then the other. But when this difference is substantial, like you describe it, it can be:
- Varicose veins
- Fluid in the scrotum
- A tumor

All these can also be ruled out by a ultrasound of the testis.

Hope this is helpful.
Let me know if you need more clarifications.

Regards,     
Dr. Papaqako

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