Kidney pain is also caused due to pyelonephritis or kidney infection. Pain occurs due to infection and inflammation of the capsule that surrounds the kidney. Unlike back pain, both these types of kidney pain are accompanied with fever, nausea and vomiting. Other potential causes of kidney pain include cancer and bleeding inside the kidneys due to injury. Dull aching pain in kidney can be caused due to polycystic kidney disease or gradual blockage of urine flow.
Sustain is defined as to support something or to endure a trial or hardship. 1  An example of sustain is for a foundation to support the house. 2  An example of sustain is to survive days without food or water.
Hence, to keep from sinking, as in despondence, or the like; to support.No comfortable expectations of another life to sustain him under the evils in this world. [Tillotson. To maintain; to keep alive; to support; to subsist; to nourish; as, provisions to sustain an army.