Rare clinical manifestations in systemic lupus erythematosus: a review on frequency and clinical presentation.

The purpose of this study was to review the frequency and clinical presentation of the rarest clinical manifestations of systemic lupus erythematosus (SLE). A list of 6 rare SLE manifestations were defined: gastrointestinal, liver, pulmonary, cardiac, ocular and neurological manifestations. Each topic was assigned to a pair of authors to perform a literature search and article review. In total, 149 articles were included in the literature review: 37 for gastrointestinal manifestations, 6 for liver manifestations, 27 for pulmonary manifestations, 50 for cardiac manifestations, 16 for ocular manifestations, 13 for neurological manifestations. Gastrointestinal disorders included several clinical presentations with variable frequency (from 0.5% to 10.7% of the cases); liver involvement included lupus-related hepatitis (9.3%) and autoimmune hepatitis (2.3%). The rarest pulmonary manifestations identified were shrinking lung syndrome, described in 1.5% of patients, while interstitial lung disease and lupus pneumonia were reported in 4% and 3% of patients respectively. Myocarditis and pulmonary hypertension were also rarely described in SLE patients although ranging from 0.4-16% and 1-14% respectively, depending on the methodology used for its identification. Ocular manifestations in SLE included some rare manifestations (reported in less than 5% of patients) and lupus retinopathy that is described in 1.2-28.8% of patients depending on methods of ascertainment. Aseptic meningitis and chorea were also confirmed as very rare manifestations being reported in less than 1% and in 0.3-2.4% of cases respectively. The results of this literature review provide the basis for a better understanding of some less-known manifestations of SLE and for stressing the need for a higher awareness in diagnostic and therapeutic protocols regarding these rare disease aspects.