I have a good reason to say that. parasites and/or candida overgrowth weaken the digestive organs, creating the perfect environment for them to proliferate. Having a candida overgrowth, let's say because of Antibiotics use, will make you more prone to parasites, because what protects you from them is compromised over time: gut flora, immune system, liver health, stomach acid, enzyme secretions... And same goes the other way, parasites can help candida proliferate.
What you mention is correct. Any gut issue, poisoning, infections... can lead to dark circles. But let me correct that for you: if you have a compromised gut, kidney, infection or whatever, well you have a compromised liver, because the liver has to filter the blood and if you're having one of those conditions you mentionned, well your blood is overloaded with toxins.
Restore proper gut flora and proper digestion>> no more infections, kidney issues, dark circles, or whatever disease you like that is related.