• What is nephrology

Nephrology is a specialty of medicine and pediatrics that concerns itself with the study of normal kidney function, kidney problems, the treatment of kidney problems and renal replacement therapy (dialysis and kidney transplantation). Systemic conditions that affect the kidneys (such as diabetes and autoimmune disease) and systemic problems that occur as a result of kidney problems (such as renal osteodystrophy and hypertension) are also studied in nephrology.

• what is hypertension

Hypertension (HTN or HT), also known as high blood pressure or arterial hypertension, is a chronic medical condition in which the blood pressure in the arteries is persistently elevated. Blood pressure is expressed by two measurements, the systolic and diastolic pressures, which are the maximum and minimum pressures, respectively, in the arterial system. The systolic pressure occurs when the left ventricle is most contracted; the diastolic pressure occurs when the left ventricle is most relaxed prior to the next contraction. Normal blood pressure at rest is within the range of 100–140 millimeters mercury (mmHg) systolic and 60–90 mmHg diastolic. Hypertension is present if the blood pressure is persistently at or above 140/90 mmHg for most adults; different numbers apply to children.

Hypertension usually does not cause symptoms initially, but sustained hypertension over time is a major risk factor for hypertensive heart disease, coronary artery disease, stroke, aortic aneurysm, peripheral artery disease, and chronic kidney disease.

sources: https://en.wikipedia.org/wiki/Nephrology, https://en.wikipedia.org/wiki/Hypertension