Can elderly UTI affect eating habits such as poor appetite at some meals?

My lady gets 3 home cooked meals each day. She always eats a hearty breakfast but sometimes picks at lunch and/or dinner. She's not at all a picky eater and is open to a wide variety of foods ... she just sometimes won't eat one or both of her other meals. We keep fruit, yogurt, some sweets for snacks and a good variety of juices (including cranberry) and water available in addition to meals consisting of vegetables and meats and serve appropriately small servings. Her general health is good and she takes no daily medications (at age 100!) She's mobile with a walker. She does currently have a UTI and has been given an antibiotic to deal with that. I just wondered in the overall picture if a UTI could affect one's appetite.