low positive

[TYH]

My daughter was tested for celiac because it runs in the family. She is positive for the celiac gene. she has an IGA deficiency so she also gets tested for IgG. The range is  >9 positive. Her bloodwork shows she is a 10 for t-Transglutaminase (tTG) IgG . We have done several tests over the past 2 years due to many different reasons and this number has gone a little up or a little down but never higher than 17. Her Deamidated Gliadin Abs, IgG once went up but now is normal.

She also possibly has another autoimmune disease.

Her biopsy was negative.

I am curious to know why only the tTG is high and not going higher? Is this celiac or not?

[Scott Adams]

Your daughter's situation presents a complex but not uncommon scenario in celiac disease diagnosis. While she carries the celiac gene and shows elevated tTG-IgG levels (consistently hovering between 10-17), the negative biopsy and fluctuating deamidated gliadin antibodies create diagnostic uncertainty. The IgA deficiency complicates interpretation, as it requires reliance on IgG-based tests which can be less specific. The persistently (but mildly) elevated tTG-IgG could indicate several possibilities: early-stage celiac disease before visible intestinal damage occurs, potential cross-reactivity from another autoimmune condition, or what's sometimes called "potential celiac disease" where antibodies are present without villous atrophy. The stability of her numbers (never exceeding 17) suggests her immune system is reacting to gluten but perhaps not mounting the full-blown attack seen in classic celiac. Given her genetic risk and possible other autoimmune disease, many experts would recommend either a trial of strict gluten-free diet to monitor symptom and antibody response, or close monitoring with repeat testing. A consultation with a pediatric celiac specialist or immunologist could help navigate these ambiguous results, as they're more familiar with these borderline cases and can weigh all factors - including her other potential autoimmune issues - in providing the most accurate assessment and management plan.