Screening and diagnostic tests have different meanings and purposes. A screening test is done to detect disease in people who do not have any symptoms of disease. You can read more about health screening tests in Singapore here.
A diagnostic test is performed to confirm the presence of disease.
In your case, IgA nephropathy can certainly be SCREENED for, at a GP clinic or at the polyclinic. Screening for IgA nephropathy is carried out by collecting a urine sample, and looking for blood or protein.
On the other hand, diagnosis for IgA nephropathy requires a kidney biopsy. This is an invasive procedure that is not done at the polyclinic. It involves taking a small piece of your kidney tissue for examination under a microscope.
Given your family history of IgA nephropathy, it sounds like the doctors who have seen you think it best for you to get a referral to see a kidney specialist (nephrologist).
They have given good advice to you, namely:
1. See a polyclinic GP, and explain your concern about IgA nephropathy in the context of your brother's diagnosis.
2. Your GP will write a referral letter to get you an appointment to see a kidney specialist at the hospital. The wait time for an appointment can be 2 - 4 weeks. The GP may also decide to perform certain basic screening tests at the same appointment as he sees fit, such as the urine dipstick test, and blood tests for your kidney markers. This is so that by the time your kidney specialist apppointment comes round, the results of the screening tests will be ready for the kidney specialist to analyse and interprete too.
