Not many conditions manifest themselves overtly. Kidneys are good examples until it too late.
This is literally my day job, and whilst blood tests measure kidney function by far the biggest cause of kidney disease in the UK is blood pressure, diabetes, and underlying heart disease.
If you have a normal blood pressure, no clinical signs of diabetes on something like a urine test, and normal 12 lead ECG the chance of you having kidney disease as an older individual is very small.
Equally sadly many of the conditions that cause kidney failure not related to the above have no cure.
The biggest 'killer' in the world (including the third world), isn't infection or cancer, its cardiovascular disease. Blood pressure, smoking, weight, diabetes, family history are the biggest risk factors in cardiovascular disease.