kidney disease vs nephropathy

kidney disease and nephropathy both are nouns.

Word	Noun	Adjective	Verb	Adverb
kidney disease	Yes	No	No	No
nephropathy	Yes	No	No	No

As nouns, kidney disease and nephropathy are synonyms defined as:

Other synonyms of kidney disease include nephrosis, renal disorder.

kidney disease (noun)	nephropathy (noun)
a disease affecting the kidneys	a disease affecting the kidneys