My 5 year old daughter in constipated and has frequent UTIs.  Every time they test her urine, she has traces of blood in it and they disregard that.  When I five her any type of laxative (Mira-Lax, PediaLax) she gets sick and gets a fever and very lethargic.  Whats going on????
I would consider the constipation and UTI as two separate ailments. For constipation, giving high fiber diet including green leafy vegetables is very important. I prefer Medial over MiraLax. However, I prefer lactulose more, although it is a prescription medication. I doubt any connections between fever and lethargy with that of constipation. Rather, these symptoms are likely to be due to the recurrent UTI. The cause of recurrent UTI could be some sort of anatomical abbe ration which could be identified by a DMS scan. Please discuss the same with your pediatrician or urologist. Further treatment would depend on the findings. If antibiotics needs to be prescribed, it is better to check the sensitivity and prescribe accordingly. Intake of plenty of water as fluids is essential.