Western Nephrology. Nephrology, Physician Assistant (PA) • 3 Providers. 1960 Ken Pratt Blvd Ste B, Longmont CO, 80501. Make an Appointment. (303) 776-7759. Western Nephrology is a medical group practice located in Longmont, CO that specializes in Nephrology and Physician Assistant (PA). Providers Overview Location Reviews XX..