Your patient was five years old when he was referred to the Children's Hospital with a severe acute infection of ethmoid sinuses. His mother reported that he had recurrent sinus infections since he was one year old. He had pneumonia from an infection with Pneumocystis carinii when he was 3 years old. These infections were treated successfully with antibiotics. While he was in the hospital with ethmoiditis, group A ̢̣-hemolytic streptococci were cultured from his nose & throat. Despite the presence of the bacterial infection his white blood count was 4200 cells /̢̣l (normal count 5000-9000 cells/̢̣l). 26% of his white blood cells were neutrophils, 56% lymphocytes, & 28% monocytes.
Seven days after admission to the hospital, during which time he was successfully treated with antibiotics, his serum was tested for antibodies to the streptococcal antigen were found, his serum immunoglobulins were measured. The results are in the table below:
Immunoglobulin (mg/dl) | Patient Levels (mg/dl) | Normals (mg/dl)
IgG | 25 | 600-1500
IgA | 0 | 150-225
IgM | 210 | 75-150
A lymph node biopsy showed poorly organized structures with an absence of secondary follicles & germinal centers
His peripheral blood lymphocytes were examined by FACS analysis & the results are shown below:
Lymphocyte Cell Surface Marker | % Positive Cells | Normal/Abnormal
CD3 | 87% | Normal
CD56 | 2% | Normal
CD19 | 11% | Normal
All his B cells had surface IgM & IgD & none were found with surface IgG or IgA. Nor did his activated T cells bind to fluorescently labeled soluble CD40. He was treated with intravenous gamma globulin each month & labeled subsequently remained free of infection.
He has an older brother & sister. They are both well. There is no family history of unusual susceptibility to infection.