Final answer:
A patient with nephropathy who suddenly develops abdominal pain, fever, and hematuria likely has acute pyelonephritis, a kidney infection with symptoms also including back pain and painful urination.
Step-by-step explanation:
A patient with nephropathy who suddenly develops abdominal pain, fever, and hematuria is most likely experiencing acute pyelonephritis. Acute pyelonephritis is an infection of the kidneys usually caused by bacteria spreading from the lower urinary tract or through the bloodstream. It typically presents with symptoms such as fever, chills, nausea, vomiting, lower back pain, and painful urination. Hematuria is commonly present (30-40% of cases) due to damage to the lining of the urinary tract.