Ataxia-telangiectasia (A-T) is characterised by progressive neurological abnormalities, oculocutaneous telangiectasias and immunodeficiency (decreased serum IgG subclass and/or IgA levels and lymphopenia). However, 10% of A-T patients present with decreased serum IgG and IgA with normal or raised IgM levels. As cerebellar ataxia and oculocutaneous telangiectasias are not present at very young age, these patients are often erroneously diagnosed as hyper IgM syndrome (HIGM). Eight patients with A-T, showing serum Ig levels suggestive of HIGM on first presentation, are described. All had decreased numbers of T lymphocytes, unusual in HIGM. The diagnosis A-T was confirmed by raised alpha-fetoprotein levels in all patients. To prevent mistaking A-T patients for HIGM it is proposed to add DNA repair disorders as a possible cause of HIGM.

The autosomal-dominant (AD) form of the hyperimmunoglobulin E syndrome (HIES) has been described as a multisystem disorder including immune, skeletal and dental abnormalities. Recently, the evaluation of patients from families in which HIES was inherited in a manner more consistent with autosomal-recessive (AR) inheritance, showed that AR-HIES is a clinically distinct disease entity. In addition to classical immunologic findings of AD-HIES, the AR form presents with severe recurrent fungal and viral infections with herpes zoster, herpes simplex and characteristic mollusca contagiosa. Furthermore, cerebral vascular sequelae, including vasculitis, infarction and haemorrhage were noted. In this report, we describe the clinical picture of two patients who showed remarkable resemblance to the description of AR-HIES, but also developed fatal aneurysmal dilatation of the thoracic aorta in adolescence. This finding may further consummate the clinical picture of AR-HIES and emphasize the possibility to develop early aortitis, most likely preceding the critical aneurysm formation at older age. This process should be anticipated during childhood in cases with AR-HIES.

Based on the present observations, we define a patient as functionally asplenic--and therefore at risk for life-threatening infections-when Howell-Jolly bodies are present in the blood smear, a very small spleen is found by ultrasound, or splenic blood flow is compromised.

2 Marinkovich MP, Taylor TB, Keene DG et al. LAD-1, the linear IgA dermatosis autoantigen, is a novel 120 kDa anchoring filament protein synthesized by epidermal cells. J Invest Dermatol 1996; 106:734-8. 3 Pas HH, Kloosterhuis GJ, Heeres K et al. Bullous pemphigoid and linear IgA dermatosis sera recognize a similar 120 kDa keratinocyte collagenous glycoprotein with antigenic cross-reactivity to BP180. J Invest Dermatol 1997; 108:423-9. 4 Zone JJ, Taylor TB, Meyer LJ et al. The 97 kDa linear IgA bullous disease antigen is identical to a protein of the extracellular domain of the 180 kDa bullous pemphigoid antigen, BPAg2. J Invest Dermatol 1998; 110:207-10. 5 Nakatani C, Muramatsu T, Shirai T. Immunoreactivity of bullous pemphigoid (BP) autoantibodies against the NC16A and C-terminal domains of the 180 kDa BP antigen (BP180): immunoblot analysis and enzyme-linked immunosorbent assay using BP180 recombinant proteins. Br J Dermatol 1998; 139:365-70. 6 Hirako Y, Nishizawa Y, Sitaru C et al. The 97-kDa (LABD97) and 120-kDa (LAD-1) fragments of bullous pemphigoid antigen 180 ⁄ type XVII collagen have different N-termini. J Invest Dermatol 2003; 121:1554-6. 7 Matsumura K, Amagai M, Nishikawa T et al. The majority of bullous pemphigoid and herpes gestationis serum samples react with the NC16a domain of the 180-kDa bullous pemphigoid antigen. Arch Dermatol Res 1996; 288:507-9. 8 Schmidt E, Herzele K, Schumann H et al. Linear IgA disease with circulating IgA antibodies against the NC16A domain of BP180. Br J Dermatol 1999; 140:964-6. 9 Zillikens D, Herzele K, Georgi M et al. Autoantibodies in a subgroup of patients with linear IgA disease react with the NC16A domain of BP180. J Invest Dermatol 1999; 113:947-53.