Nephrolithiasis is the condition characterized by the presence of nephroliths (also referred to as calculi or kidney stones) which are stones located within the kidney pelvis. Nephroliths have several potential causes, and a host of possible presentations are associated with their presence. Some factors may enhance the susceptibility to nephrolithiasis such as congenital abnormalities, metabolic disorders or disorders that promote urine retention, but no specific underlying disorder need exist.

Individuals with kidney stones may be have no clinical signs, although some patients may be quite ill, as the presence of stones can cause pain and lead to kidney failure, sepsis (infection throughout the bloodstream) and even death. Depending on the specific case, specific diagnostics and therapeutics are tailored to the individual.

Several diseases/disorders are similar to nephrolithiasis. These include:

Pyelonephritis, which is an infection of the kidney

Urolithiasis, which are stones anywhere throughout the urinary tract

Lower urinary tract infection

Chronic kidney failure may be associated with or the result of nephrolithiasis.

Other causes of abdominal pain such as pancreatitis or peritonitis (inflammation of the abdominal cavity) need to be considered, as some animals with nephrolithiasis will experience abdominal pain.

Disorders associated with back pain such as intervertebral disc protrusion or a spinal infection or tumor may need to be differentiated.

Disorders that cause increased thirst and urination including hyperadrenocorticism (Cushing's disease), diabetes mellitus, kidney disease and liver disease