Published online Dec 14, 2014. doi: 10.3748/wjg.v20.i46.17686
Revised: June 17, 2014
Accepted: August 13, 2014
Published online: December 14, 2014
Processing time: 238 Days and 21.3 Hours
Selective IgM deficiency (sIGMD) is very rare; it may be associated with celiac disease (CD). We present the case of an 18-year-old man with sIGMD masking seronegative CD. Symptoms included abdominal pain, diarrhea and weight loss. Laboratory tests showed reduced IgM, DQ2-HLA and negative anti-transglutaminase. Villous atrophy and diffuse immature lymphocytes were observed at histology. Tissue transglutaminase mRNA mucosal levels showed a 6-fold increase. The patient was treated with a gluten-free diet (GFD) and six months later the symptoms had disappeared, the villous architecture was restored and mucosal tissue transglutaminase mRNA was comparable to that of healthy subjects. After 1 year of GFD, a complete restoration of normal IgM values was observed and duodenal biopsy showed a reduction of immature lymphocytes and normal appearance of mature immune cells.
Core tip: Selective IgM deficiency is a rare condition, associated in 5% of cases to Celiac Disease (CD). The CD diagnosis in patients with immunoglobulin deficiencies is based only on response to a Gluten-Free Diet (GFD). Deposits of tissue transglutaminase are found in duodenal samples of seronegative CD. Our case (IgM deficiency/seronegative CD) disclosed novel insights: (1) it is possible to observe a selective association of IgM deficiency/seronegative CD; (2) the histological diagnosis of CD may be complex due to poor lymphocyte maturation; (3) mRNA coding for tissue transglutaminase in duodenal mucosa could be a useful diagnostic tool; and (4) GFD may reverse IgM deficiency by promoting lymphocyte maturation.