Agammaglobulinemia: from X-linked to Autosomal Forms of Disease.

Interruptions or alterations in the B cell development pathway can lead to primary B cell immunodeficiency with resultant absence or diminished immunoglobulin production. While the most common cause of congenital agammaglobulinemia is X-linked agammaglobulinemia (XLA), accounting for approximately 85% of cases, other genetic forms of agammaglobulinemia have been identified. Early recognition and diagnosis of these conditions are pivotal for improved outcomes and prevention of sequelae and complications. The diagnosis of XLA is often delayed, and can be missed if patient has a mild phenotype. The lack of correlation between phenotype and genotype in this condition makes management and predicting outcomes quite difficult. In contrast, while less common, autosomal recessive forms of agammaglobulinemia present at younger ages and with typically more severe clinical features resulting in an earlier diagnosis. Some diagnostic innovations, such as KREC level measurements and serum BCMA measurements, may aid in facilitating an earlier identification of agammaglobulinemia leading to prompt treatment. Earlier diagnosis may improve the overall health of patients with XLA.

Infant Anaphylaxis: A Diagnostic Challenge.

PURPOSE OF REVIEW: Infant anaphylaxis has been increasing in incidence; however, significant gaps in the literature remain. The aim of this article is to review the most recent literature pertaining to infant anaphylaxis and discuss recent findings related to epidemiology, diagnosis, management, and prevention. RECENT FINDINGS: There is no accurate report of the incidence and prevalence of anaphylaxis in infancy. Food is the most common trigger for infant anaphylaxis reported. The diagnosis of anaphylaxis in infants is often missed, and, even when the diagnosis is made, epinephrine continues to be under-utilized. An epinephrine autoinjector with a shorter needle and lower dose is now available for infants. Concise criteria specifically focusing on infant anaphylaxis is needed to streamline its diagnosis and management. Diagnosis is underrecognized in infants leading to improper treatment. When the diagnosis is made, epinephrine continues to be under-utilized and under-prescribed in infants.