The purpose of this study was to characterize the clinical and serological features of a large cohort of patients with antinuclear antibody (ANA) positive undifferentiated connective tissue disease (UCTD). Consecutive patients with UCTD, followed up at the Rheumatology Clinic of the participating centers, were included. Data from these patients were obtained by clinical evaluation and chart review. All patients were diagnosed as having UCTD on basis of the following criteria: positive ANA plus at least one clinical feature of connective tissue disease, but not fulfilling classification criteria for any differentiated connective tissue disease. One hundred eighty-four patients were studied (female patients—94.5%; mean age at time of evaluation—47 years). The most prevalent manifestations were arthralgia (66%), arthritis (32%), Raynaud’s phenomenon (30%), sicca symptoms (30%), and leukopenia (19%). The prevalence of ANA was 100%, anti-SSA 20%, anti-dsDNA 14%, and anti-SSB 7%. Patients with anti-dsDNA/anti-Sm, anticentromere/anti-Scl70, or anti-SSA/anti-SSB antibodies more frequently presented a set of manifestations close to systemic lupus erythematosus (SLE), systemic sclerosis, or Sjögren syndrome, respectively. We analyze a large cohort of UCTD. Seventy-two percent of these UCTD patients present lupus-, scleroderma-, or Sjögren-like features but do not fulfill classification criteria and mostly present a mild disease.

The authors report the case of a 48-years-old Caucasian women, with a previous diagnosis of systemic lupus erythematosus characterized by asthenia, fever, skin rash, alopecia, Raynaud's phenomenon, arthritis, pericardial effusion, interstitial pulmonary involvement, diffuse proliferative glomerulonephritis with crescents and anemia. The presence of severe anemia refractory to high doses of glucocorticoids (1 mg//Kg/day), iron therapy and blood transfusions, associated with a low reticulocyte count determined the execution of a bone marrow aspiration, biopsy and immunophenotyping, which were compatible with the diagnosis of Myelodysplastic Syndrome. The treatment with erythropoietin (5.000U 3x/week) and cyclophosphamide pulses (1 gr/m(2) month) induced complete regression of morphologic bone marrow changes and anemia. The main causes of anemia in lupus patients are discussed.