Do not feed any cat Simply Nourish! It almost killed our cat. It gave him crystals in his urethra so bad he had to get his penis snipped down to where his urethra was wide enough he wouldn’t incur anymore crystal issues. Unfortunately he passed February 2016 from FIV. We miss him every day and no fur baby should ever have to fear for their life, nor go through the medical procedures he had to suffer through. Raw diets are the best diets. If you’re going to go canned wet food, PetGuard has worked best for my kiddos.Now I'm thoroughly convinced it was the Nature's Variety wetfood causing the constipation - we switched the to something else (Simply Nourish canned) and my cat pooped 3-4 stools within a couple of hours after eating. We didn't end up going back to the vet for an enema.
Bear in mind, on the NV wetfood, we were also giving probiotics, 1/4 teaspoon of Miralax and 1/4 teaspoon of olive oil under the vet's instructions and he still hadn't pooped for about 3 days.
Anyway...we will still be going back to the vet eventually, but not til our kitty finishes his cycle of antibiotics for the suspected UTI. They will repeat the blood tests and urinalysis to see if the antibiotics cleared things or if they are looking at kidney disease.