Table 1.
Characteristics of 59 index patients with subnormal IgGSc and normal total IgGa
| Characteristic | Subnormal IgG1 | Subnormal IgG3 | Subnormal IgG1+ IgG3 | All patients |
|---|---|---|---|---|
| n | 13 | 33 | 13 | 59 |
| Mean age, years ± SD | 34 ± 13 | 45 ± 12 | 48 ± 13 | 44 ± 13 |
| Men, % (n) | 23.1 (3) | 6.1 (2) | 38.5 (5) | 16.9 (10) |
| Diabetes, % (n) | 0 | 6.1 (2) | 15.1 (2) | 6.8 (4) |
| Mean BMI, kg/m2 ± SD | 27.3 ± 7.8 | 26.6 ± 5.7 | 30.8 ± 12.8 | 28.1 ± 8.2 |
| Autoimmune condition(s), % (n) | 23.1 (3) | 42.4 (14) | 30.8 (5) | 37.3 (22) |
| Atopyb, % (n) | 23.1 (3) | 36.4 (12) | 15.4 (2) | 28.8 (17) |
| Other allergyc, % (n) | 53.8 (7) | 51.5 (17) | 46.2 (6) | 50.8 (30) |
| Mean IgA, mg/dL ± SD | 154 ± 74 | 206 ± 106 | 196 ± 91 | 200 ± 95 |
| Mean IgM, mg/dL ± SD | 263 ± 86 | 120 ± 99 | 104 ± 75 | 117 ± 90 |
| Median days between pre-, post-PPSV23 tests (range) | 32 (27–47) | 35 (19–129) | 32 (19–158) | 33 (19–158) |
aAbbreviations: Ig Immunoglobulin, BMI Body mass index, PPSV23 Polyvalent pneumococcal polysaccharide vaccination. IgG subclass levels were measured before IgG replacement therapy. Mean ± 2 SD was defined as reference ranges for all Ig measurements. Ig reference ranges are: total IgG 7.0–16.0 g/L (700–1600 mg/dL); IgG1 4.2–12.9 g/L (422–1292 mg/dL); IgG2 1.2–7.5 g/L (117–747 mg/dL); IgG3 0.4–1.3 g/L (41–129 mg/dL); IgG4 0–2.9 g/L (1–291 mg/dL); IgA 700–4000 mg/L (70–400 mg/dL); IgM 400–2300 mg/L (40–230 mg/dL). Subnormal Ig concentrations were defined as those below the corresponding reference limits
bAllergic asthma, allergic rhinitis, or allergic dermatitis/eczema
cUrticaria, angioedema, or anaphylaxis