SERPING1 and hyperinsulinemic hypoglycemia, familial, 4: Above all, relying just in ICD 10 D84.1 could be a risky situation, since this code is just related to C1-INH deficiency, thus, leaving out even the chance of a proxy for estimate HAE nC1-INH, the estimation with the present methodology accounts just for 90%–95% of all HAE cases.