Is it ethical for the federal government to pay the costs of kidney dialysis for all patients, regardless of age or income, as it now does, but not to pay the costs of other illnesses?

1. Is it ethical for the federal government to pay the costs of kidney dialysis for all patients, regardless of age or income, as it now does, but not to pay the costs of other illnesses? Which would be more reasonable and more feasible: extending benefits to those who have other illnesses or withdrawing them from those who need kidney dialysis?