Lupus Enteritis as the Only Manifestation of Active Systemic Lupus Erythematosus

Abstract

Lupus enteritis is a rare manifestation of systemic lupus erythematosus (SLE). It is a difficult diagnosis to make, especially in the absence of other symptoms related to active SLE. We present a case of a 25 year old female who presented with lupus enteritis as the sole manifestation of active SLE. A 25 year old female presented to the ED with diffuse abdominal pain, diarrhea, nausea, and vomiting for 2 days. She had a medical history of seasonal allergies. Family history was significant for SLE in her cousin. Her vital signs were normal, and physical exam revealed lower abdominal tenderness. A CT of the abdomen showed marked circumferential wall thickening and edema of the proximal and mid small bowel loops predominantly involving the submucosa (Image 1). Our main differential diagnoses were intestinal angioedema and mesenteric vein thrombosis. The mesenteric vessels were patent and without evidence of thrombosis. Infectious workup was negative. Laboratory testing for hereditary angioedema showed a normal C1 Esterase Inhibitor level and low C3 and C4 levels. Autoimmune work-up showed elevated ANA (13.6), anti-Smith antibody (ab), and anti-RNP ab (Table 1). The patient was diagnosed with SLE enteritis. She was maintained on bowel rest, given intravenous (IV) hydration, and started on methylprednisolone 60 mg IV daily. She had significant improvement of all her symptoms and was discharged on prednisone 75 mg by mouth daily. In SLE, isolated gastrointestinal activity without other organ involvement is highly unusual. Lupus enteritis presents with non-specific symptoms, making the diagnosis difficult. Nevertheless, it is important to identify this disease manifestation as the mortality among patients with SLE with acute abdominal pain is approximately 11%. Lupus enteritis causes submucosal edema of the jejunum and ileum. The classic findings on CT scan include circumferential bowel wall thickening (“target sign”), dilation of intestinal segments, and engorgement of mesenteric vessels (“comb sign”). The CT scan in our case showed the “target sign”. Given her negative work up for hereditary angioedema and her family history of lupus, we decided to test for SLE. We did not perform an upper endoscopy because it often does not contribute to diagnosis. It's important to note that while most sources advocate pulse dose steroids, we were able to achieve symptomatic control with methylprednisolone 60 mg daily.2543_A Figure 1. Ab (antibody); ANA (anti-nuclear antibodies); dsDNA (double-stranded DNA); Anti-RNP (anti-ribonucleoprotein).2543_B Figure 2. Image 1. Marked circumferential wall thickening consistent with “target sign” involving multiple loops of proximal/mid small bowel. There is predominantly submucosal thickening/edema, more predominantly in the mid abdomen. The thickened small bowel loops are minimally dilated. However, there is no transition point. There is moderate volume of ascites.