Five congenital agammaglobulinemic (CA) boys, started their recurrent bacterial infections between the ages of 3-18 months, presenting otitis (4), pneumonias (4), chronic diarrhea (4), meningitis (2), septicemia (2), septic arthritis (1) and urinary infection (1). The gamma globulin fraction was below 0.08 mg/dL in all patients. IgG, IgA, IgM and IgE levels were always below 50 mg/dL, 2 mg/dL, 35 mg/dL and 20 IU/mL, respectively. Secretory IgA was non-detectable in all patients. Total complement levels were normal (3) and the C3 fraction was elevated in 4 patients. The in vitro response of peripheral lymphocytes to PHA was normal in 4 patients, as well as the number of OKT3, OKT4 and OKT8 cells (2).