In order for the Kallmann Syndrome (KS) to be diagnosed with accuracy, the first thing your doctor needs is a blood test to assess your hormone levels, as well as to find out a potential deficit in the production of GnRH.
Since KS is associated with smell disorders, an olfactory test is highly useful as well. Unfortunately, this kind of tests lead to confusing results in most of the cases. Olfactory bulbs can be examined by means of MRI, too.
Finally, a genetic screening to detect potential affected genes in the patient will be required as well.