Pyelonephritis
Pyelonephritis is a urinary tract infection that affects the ureters (the tube connection between kidney and bladder) and, in particular, the beginning of the ureters (pelvis kidney). It occurs more often in young women.
When these parts of urinary systems suffer the bacterial infection, it usually is a serious clinical condition and requires an urgent attention. Symptoms include high degree fever, frequent urination, and harsh pain sensation when urinating. As the infection progresses, there may have bacteria pus in the urine, which gives cloudy or milky urine. The infection may cause the bleeding or blood in the urine leading to dark red/brown colored urine. Other symptoms include the back or abdominal pain, and nausea and vomiting.
Please go to see your doctor for diagnosis and treatment when you have above symptoms, or have fever with painful urination or urine color change.