Objective: Cartilage-hair hypoplasia (CHH), a metaphyseal chondrodysplasia,
is usually associated with impaired cellular immunity. This study evaluate
s tumor al immunity in patients with CHH.
Methods: The concentrations of immunoglobulins G, A, and M (IgG, IgA, and I
gM) and Ige subclasses were studied in 20 patients. Data for 5 additional p
atients with recurrent infections were retrospectively reviewed.
Results: Seven of the prospectively evaluated patients (35%) had defective
humoral immunity. Three patients had IgA deficiency. Four patients had IgG2
deficiency, accompanied by Ig A deficiency, IgG4 deficiency, or both in 3
patients. IgG4 was low in most patients. Increased infections were usually
associated with supranormal Ige and IgG1 and subnormal IgA, IgG2, or IgG4 c
oncentrations. One retrospectively reviewed patient had severe hypogammaglo
bulinemia, and 3 had multiple IgG subclass deficiencies.
Conclusions: Humoral immunity is impaired in CHH and contributes to the inc
reased susceptibility to infections.