Phenotypic parameters predict time to normalization in infants with hypogammaglobulinemia.

Purpose: Infants with recurrent infection may be found to have hypogammaglobulinemia without impaired specific antibody responses. Many will be diagnosed with transient hypogammaglobulinemia of infancy.

Methods: This study used a parametric survival analysis of 100 infants with hypogammaglobulinemia to predict time to normalization.

Results: Aggregate initial immunoglobulins (IgG + IgA + IgM), as a percentage of age-adjusted normal, predicted time to resolution: median time to resolution for the infants in the lowest quartile of aggregate levels (≤81 % of age-adjusted lower limits) was greater than 5 years, with 34 % resolving in 3 years. For infants in the highest quartile (≥130 % of age-adjusted lower limits), the median was 9.9 months, with 77 % resolving in 3 years (P = 0.008). Initial IgG level, as a percentage of age-adjusted normal, also predicted resolution: the median time in the lowest quartile (≤78 % of age-adjusted lower limits) was greater than 5 years, with 36 % resolving in 3 years. In the highest quartile (≥128 %), the median time was 14.5 months, with 70 % resolving in 3 years (P = 0.010). Male sex was associated with more rapid resolution. The median time in males was 13 months, with 73 % resolution in 3 years. The median time in females was greater than 5 years, with 32 % resolution in 3 years.

Conclusions: These results suggest that if a term infant presents with hypogammaglobulinemia, protective specific antibody titers, and an absence of other known immune deficiency, initial immunoglobulin levels and sex may predict time to normalization.