Intestinal pseudo-obstruction in systemic lupus erythematosus: an uncommon but important clinical manifestation.

OBJECTIVES: To document intestinal pseudo-obstruction (IpsO) as a recognised clinical manifestation of systemic lupus erythematosus (SLE) and a possible new clinical entity with its apparent association with ureterohydronephrosis.
METHODOLOGY: We report six lupus patients who presented with IpsO and review 12 other cases from an English literature search. IpsO is defined as the presence of clinical features suggestive of intestinal obstruction but without organic obstruction, namely absence of bowel sounds, presence of multiple fluid levels on plain abdominal X-rays and exclusion of organic obstruction by imaging or surgical procedure. Other clinical characteristics related to the underlying lupus, serological and histological findings, treatment modalities and outcomes of these patients were reviewed.
RESULTS: All 18 patients fulfilled the ACR revised classification criteria for SLE. None showed any clinical features of scleroderma or overlap syndrome. The mean age of onset of IpsO was 29.0 (15-47) y. The female to male ratio was 16:2. Nine patients had IpsO as the initial presentation of their underlying lupus. Coexisting lupus involvement of other organ systems included glomerulonephritis (n=7), thrombocytopenia (n=5) and cerebral lupus (n=3). The serology data and autoantibody profile of some of the previously reported patients were incomplete. In our series, anti-Ro antibody was positive in 5/6 while anti-RNP was found in 1/6 patients only. All our patients had active lupus serology at presentation. 17/18 patients required the use of high dose systemic corticosteroid therapy while one patient responded to topical adrenocorticotrophin hormone treatment. Response was good and was observed early after commencement. Azathioprine was used as maintenance therapy in 6/18 patients with good effects. An apparent association with the presence of bilateral ureterohydronephrosis was found in 12/18 patients. These patients presented with dysuria without positive bacterial culture though features of chronic interstitial cystitis were not invariably found in these patients.
CONCLUSION: IpsO is an uncommon but important manifestation of SLE. The underlying pathology is not fully understood but it may be related to immune complex deposition. The finding of coexisting ureterohydronephrosis suggests that there may also be a central smooth muscle motility problem of neuropathic or myogenic pathophysiology which may or may not be secondary to vasculitis. Early recognition and treatment of IpsO in SLE is important.