Selective immunoglobulin A (IgA) deficiency is the most common primary immunodeficiency and is characterized by low or absent serum IgA levels, predisposing affected individuals to recurrent infections, autoimmune disorders, and inflammatory conditions. Emerging evidence suggests a possible association between Kawasaki disease and IgA deficiency, highlighting the role of mucosal immunity and abnormal immune responses to infectious triggers. IgA-deficient patients may produce anti-IgA antibodies, and have a potential risk of anaphylactic reactions to the transfusion of any blood products which contain trace amounts of IgA, such as immunoglobulins.We describe a case of a girl 16 months old who developed an incomplete form of KD with persistent fever for nine days and a mild rash of the trunk with elevation of inflammatory blood test ( ESR: 92 mm/h, PCR: 11,4 mg/dl) and high levels of platelets ( PLT: 866.000/mmc) with a concomitant deficit of Ig A ( 1 mg/dL). We performed at ninth day of fever an echocardiogram showing a little fusiform aneurysm of LMCA ( 3,4 mm, Z-score + 4,7 ) with normal diameter value of LAD and RAD . She promptly responded to high doses of IVIG ( 2 g/Kg) and prednisone 1 mg/kg without signs Of anaphylaxis after the therapeutic infusion. The patient showed stable defervescence from the day after the therapy administration and the echocardiogram of control on eleventh day of illness didn’t show any CAA with normalization of LMCA diameter.
KD associated with sIgAD has important implications in the pathogenesis of KD.
Although selective IgA deficiency (sIgAD) is not the cause, it can affect the immune response, leading to milder symptoms of KD but also to problems with standard therapy (IVIG), requiring alternative treatments such as cyclosporine A. Furthermore, KD itself may be associated with intestinal barrier dysfunction and IgA deposition, suggesting a key role for this immunoglobulin and intestinal inflammation in the pathogenesis of the vasculitis.
Collecting data of clinical presentation, outcome and response to standard and alternative treatments of patients with deficit of Ig A associated to Kawasaki disease can help us to understand the possible role of Ig A into the disease pathophysiology.