Based on the eight‑dimensional framework of Prim‑Lex theory, this paper redefines uremia (end‑stage renal disease) as “an irreversible phase transition of the kidney‑body system from a global coherent state to a localized decoherent state.” Its occurrence is not a linear progression of a single etiology but a collective phase transition of the eight‑dimensional system: Prim‑Unity·Prim‑Fire (decoherence of the NADH/NAD⁺ redox couple in renal tubular epithelial cells) → Two Principles·Yin‑Yang (polarization of AMPK–mTOR signaling) → Three Realms·GC⁴A (disruption of cross‑scale damage communication among glomeruli, tubules, and interstitium) → Four Phenomena·Four Colors (abnormal cell cycle re‑entry and apoptosis of renal tubular epithelial cells) → Five Elements·Five Models (quintuple coupling of glucotoxicity, lipotoxicity, proteinuria, oxidative stress, and mitochondrial dysfunction) → Six Dimensions·Six Directions (collapse of podocyte mitochondrial cristae structure) → Seven Luminaires·Seven Rhythms (loss of circadian rhythm of glomerular filtration rate) → Eight Trigrams·Eight Information (uremic toxin entropy explosion driven by gut‑kidney axis dysbiosis). This paper systematically elaborates the pathological manifestations, diagnostic methods, and targeted therapeutic strategies for each dimension, demonstrates the scientific validity of the eight‑dimensional comprehensive coherent‑state criterion ,as a unified benchmark for uremia diagnosis, staging, and efficacy evaluation, and proposes a five‑tier graded diagnosis and treatment pathway for “life‑cycle kidney disease prevention – screening – critical window intervention – systematic rehabilitation – renal replacement therapy,” thereby completing the scale bridging of Prim‑Lex theory from “planetary civilization governance” to “kidney health governance.”