Final answer:
A normal filtration fraction (FF) result is about 21.7%. In PP screening, this FF is derived from a GFR of 120 ml/min and an RPF of 574 ml/min. The appropriateness of using PSA or PCA3 tests for prostate cancer screening is debated due to potential overdiagnosis and harmful side effects from treatment.
Step-by-step explanation:
PP Screening Normal Result.
A normal result at PP screening, which assesses kidney function, would involve a filtration fraction (FF) measurement. This is calculated using the Glomerular Filtration Rate (GFR) and the Renal Plasma Flow (RPF). In a normal healthy person, the GFR is about 120 ml/min and the RPF is approximately 574 ml/min, resulting in an FF of about 0.217 or 21.7%. During the early stages of essential hypertension, FF remains normal, but it may increase as the condition progresses. Conversely, in cases of glomerular nephritis, a reduced FF is observed. Additionally, the renal clearance test for tubular secreting mass typically uses para-aminohippurate (PAH) with a normal level at 80 mg/min/1.73 sqm of body surface area, when plasma PAH concentration is 150 mg/100 ml.
As for cancer screening tests such as PSA and PCA3, these have been debated due to potential overdiagnosis and overtreatment of diseases that may not be life-threatening. For prostate cancer screening, the US Preventative Services Task Force recommended against using the PSA test for healthy men because it may not reduce mortality and can lead to significant side effects from unnecessary treatment. The PCA3 test is more accurate, but screening still poses similar issues. Whether all healthy men should be screened for prostate cancer and whether genetic risk screening for cancer or other diseases should be conducted remain controversial decisions that depend on a balance between benefits and potential harms.