Brief Answer:
Group/colonies of bacteria.

Detailed Answer:
Hi,

I went through the query and understood your concern.

In urine test colonized mean the group and usually refer to bacterial colonies. The bacteria will form a group and on microscopic examination it appears as a group (colony). This along with the symptom of pain in right side suggest UTI and hence you require antibiotics / urinary antiseptics.

Drink plenty of fluids and take anti spasmodic like dicyclomine with NSAID like aceclofenac for pain along with antibiotic. Since these are prescription drugs contact your doctor for prescription.

I hope this information helps you and answered your query.
Feel free to ask for any further questions and I will be glad to answer them.

Wish you good health and faster recovery.
Regards

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