There are as many as 500,000 undiagnosed cases of PI in the US alone. However, awareness of PI is low among both physicians and the general public, and many patients are left undiagnosed. Reasons for this may include: A lack of awareness of PIs and/or their management. The masking of symptoms due to frequent antibiotic use. Symptoms may present differently to different specialists over a number of years. The lengthy process of confirmation, which includes many tests and consultations