3.2.0.0 Di­ag­no­sis

In a pa­tient with clas­sic symp­toms, mea­surement of plas­ma glu­cose is sufficient to di­ag­nose di­a­betes (symp­toms of hy­per­glycemia or hy­per­glycemic cri­sis plus a ran­dom plas­ma glu­cose ≥200 mg/dL [11.1 mmol/‍L]). In these cases, know­ing the plas­ma glu­cose level is crit­i­cal be­cause, in ad­di­tion to confirming that symp­toms are due to di­a­betes, it will in­form man­age­ment de­ci­sions. Some pro­viders may also want to know the A1C to de­ter­mine how long a pa­tient has had hy­per­glycemia. The cri­te­ria to di­ag­nose di­a­betes are list­ed in Table 2.2.