Coexistence of Celiac Disease and Systemic Lupus Erythematosus: A Case Report

Celiac disease (CD) is a chronic inflammatory disorder of the small intestine triggered by the ingestion of gluten. It has been associated with auto-immune disorders. Although many similarities exist between the pathogenesis of CD and systemic lupus erythematosus (SLE), their association has been rarely reported. We describe a case of a 23-year-old woman diagnosed with CD, and one year later developed SLE. CaSE REpORt

The diagnosis of CD was established, and a glutenfree diet was initiated. The six months follow-up showed a resolution of gastrointestinal symptoms and a weight gain. Additionally, laboratory parameters were within normal range. One year after, the patient presented with polyarthralgia, photosensitivity, alopecia, ascites and lymphopenia (700 cells/mm3). Serum anti-nuclear antibodies were positive with a titer of 1/160 and a homogeneous pattern. The titer of anti-dsDNA was high at 55 IU/l. The kidney function and cardiac exploration did not show any abnormality. The diagnosis of SLE associated with CD was made, and the patient started antimalarial drugs in association with oral prednisone 20 mg/day followed by a gradual taper. At two-year follow-up, a clinical remission was achieved, gastrointestinal symptoms were improved and the laboratory parameters were normal.

Introduction
Systemic lupus erythematosus (SLE) and celiac disease (CD) are complex and clinically heterogeneous autoimmune disorders. Their pathogeneses is still not completely understood; genetic and environmental factors are implicated [1-3]. SLE involves the gastrointestinal tract which is well documented [4] but its association with CD is rare [5,6]. Nevertheless, some data suggest that patients with SLE develop CD and vice versa, highlighting a possible association between these diseases [3,7]. We report the case of a 23-yearold woman with CD, who developed SLE one year after the diagnosis.

Case Presentation
A 23-year-old woman presented with pallor, abdominal pain, diarrhea, steatorrhea and weight loss. Physical examination showed meteorism, bilateral leg edema and muscle atrophy.
The laboratory evaluation revealed abnormal results, which included iron deficiency anemia at 6 g/dl, hypocholesterolemia at 0.6 g/l, and hypoalbuminemia positive antigliadin antibodies in patients with SLE is common [5].

Conclusion
The association between systemic lupus erythematosus and celiac disease deserves the attention of researchers. Further researches are needed in order to determine the true prevalence of this coexistence.

Conflicts of Interest
None.

Financial Support
None. Several theories have been proposed to explain this association, including the duration of exposure to gluten which would increase the risk of developing autoimmune diseases [13], and a genetic predisposition (HLA B8 DR3) [9]. High frequency of histocompatibility antigens HLA-DR3 is observed in both CD and SLE [2,5, 14,15]. Likewise, SLE is associated in 40 to 70% of cases with HLA-DR3 [15]. Six presented with CD. The mean age at diagnosis of the association SLE-CD was 28 years (16-47 years). CD occurred ten and twenty-three years before SLE respectively, in two cases. CD occurred concomitantly in four cases. The laboratory finding showed malabsorption. Mucosal histopathology revealed villous atrophy, classified as 4 according to Marsh's scale in two cases, stage 3 in one and stage 2 in two, and was normal in one case. All the patients were tested positive for anti-gliadin, anti-endomysial and anti-transglutaminase antibodies. Four patients had a cutaneous and articular form of SLE without visceral involvement. Lupus nephritis occurred in one case [16].

References
Zitouni, et al. reported five cases over a 4-year period. CD and SLE occurred concomitantly in one patient, whereas CD preceded SLE in one patient and was diagnosed afterwards in the remaining 3 patients. Villous atrophy on duodenal biopsy specimens with a favourable response to a gluten-free diet was noted in all the 5 patients. Only 4 patients had positive serological tests for celiac disease and only three had abdominal symptoms [17].
Due to its rarity, the association of CD with SLE is considered by some authors to be fortuitous. The study of Rensch, et al. included 103 patients with SLE, who were tested for the serological presence of IgA and IgM antigliadin and IgA antiendomysial antibodies. Those with positive serology underwent esophagogastroduodenoscopy with duodenal mucosal biopsy. Twenty-four patients (23.3%) tested positive for antigliadin antibody. None of them were found to have endoscopic or histological evidence of CD, making the false positive rate of antigliadin antibody 23%. According to the authors of this study, there seems to be no association between CD and SLE since false