Lupus erythematosus and Appendicitis

Pediatric Rheumatology 2008, 6:10doi:10.1186/1546-0096-6-10

2008 Cellini et al; licensee BioMed Central Ltd.

A 16 year old female with systemic lupus erythematosus presents with acute appendicitis. Final pathologic analysis of the appendix describes a lupus-associated vasculitis.

Acute abdomen in patients with systemic lupus erythematosus (SLE) can pose a diagnostic and therapeutic challenge. Most of these patients are on chronic steroid treatment which may mask symptoms and lead to delay in diagnosis. Delay in diagnosis and treatment can increase mortality. Lupus-associated vasculitis is reported to be the cause of acute abdomen in up to 60% of SLE patients [1]. We report a case of a female patient who was referred to us with symptoms of acute abdomen due to appendicitis associated with vasculitis.

This is a 16 year old female with a past medical history significant for systemic lupus erythematosus who presented to the ER with a one day history of right lower quadrant pain. The pain was described as constant and sharp, becoming steadily worse over the course of a day. She reported a decrease in appetite since the onset of symptoms. Past medical history was significant for SLE with biopsy- proven lupus glomerulonephritis, hypertension and hypothyroidism for which she was taking Prednisone 15 mg each day, Vasotec and Synthroid, respectively.

On exam the patient was afebrile with stable vital signs. She did not appear to be in any distress. Her abdomen was obese, and non-distended. She was moderately tender to palpation in the right lower quadrant but did not exhibit any signs of rebound or guarding. Her laboratory values were significant for a WBC count of 10.2 with 84% neutrophils and a urinalysis that was positive for 5–10 WBC/hpf and moderate amount of bacteria. A CT scan of the abdomen and pelvis was obtained which revealed a slightly prominent, hyperemic, non-air or fluid filled appendix with trace pelvic ascites.

Studies have found that vasculitis is the cause of acute abdomen in 35–60% of cases of SLE . Causes of vasculitis- associated acute abdomen in SLE patients include intestinal ischemia and necrosis, pancreatitis and cholecystitis. Acute appendicitis is usually considered a non-SLE-related cause of acute abdomen and is considered separate from the vasculitits- associated cases. Our case, however, suggests that there might be a cause and effect relationship between the two.