Opportunistic infections (OIs) are the main cause of morbidity and mortality among patients with HIV in developing countries. It is therefore critical that accurate diagnoses are made and that they are correctly recorded and managed. We reviewed 200 randomly selected records of clinical encounters with HIV infected pregnant women attending the ante-natal care (ANC) clinic in July 2012 at the Jaramogi Oginga Odinga Teaching and Referral Hospital in Kenya. None of the clients in WHO stage 4 and 2.8% of those in WHO stage 3 had a new OI diagnosis recorded during the clinical encounter. This data suggests current under-recording of OIs and the inconsistency between WHO staging and OI diagnosis. Structured methods such as SNOMED CT have the potential to improve complete and accurate recording of OIs which, in turn, enable automatedand accurate WHO staging.