Brief Answer:
several possibilities can be there..

Detailed Answer:
Hello XXXXX, Welcome to HCM,
I've gone through your query and understand your concern,

I believe you've done Glycemic control study (HbA1C) along with the FBS and PPBS already (if not done yet, then do get it done to in to it)..

Apart from Diabetes, there's numerous other causes (both medical as well as non-medical) behind this..

Yes, your doctor's partly right, as urinary tract infection can certainly cause this (as presence of micro-organisms i.e. bacteria ,fungus can attract the ants)..

Presence of protein in urine (proteinuria) , RBCs, certain casts and crystals in urine can also result in the same..

There's even certain metabolic condition like Renal Glycosuria (secretion of excessive glucose in urine with/without diabetes) can also result in the same fashion, but please note that it's a quite rare, genetic disorder..

You should also note that several foods and beverages (excessive sugar rich foods , certain fruit juices in excessive quantity, excessive consumption of alcohol, even dehydration) all can result this..

Getting done a proper Urine Routine microscopy analysis along with Culture Sensitivity will through some light in to this..if the results along with the glycemic index turns out within normal limits then you shouldn't worry.. in that case, just be vigilant and under routine follow-ups of your doctor..nothing too concerning..

Hope this clarifies the doubt, let me know if there's any further queries..

Take Care
Kind Regards

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