Adult primary immune deficiency: what are we missing?

BACKGROUND: More than 200 primary immune deficiencies have been described. In adults, their identification can be difficult. The lack of timely referrals, diagnostic facilities, and available expertise often delay appropriate treatment. Because an increasing number of adults are now diagnosed with immune deficiencies, there is a need to better understand the immune deficits in this age group. The study objective was to analyze the diagnostic spectrum of adults with primary immune deficiency and to determine the presumptive diagnostic accuracy of the referring physicians. METHODS: We conducted a retrospective chart review over a 10-year period of all individuals referred to a dedicated center for adults with primary immune deficiency. Suspected cases were confirmed using standard clinical criteria and state of the art immune assays. RESULTS: Of the 381 individuals studied, 244 were diagnosed as immune deficient. Of these, 210 had primary immune deficiency classified as novel, defined, and undefined. Forty-three patients had a prior diagnosis and were referred for follow-up care, and 201 patients were newly diagnosed. Most patients had common variable immune deficiency. Despite an apparent high index of suspicion in initiating the referrals, only one third of these patients had a prior quantitative assessment of serum immunoglobulins. CONCLUSIONS: In this first known analysis of a large cohort of adults with suspected immune deficiency using established diagnostic criteria, we confirmed the diagnosis in two thirds of all patients. Our findings highlight the wide spectrum of primary immune deficiency states seen in adult medical practices and the need for increased awareness of their existence.