Background and aims To examine the clinical features, prognosis and response to treatments for severe thrombocytopenia in patients with connective tissue diseases (CTDs).

Methods The data of 131 CTDs inpatients with severe thrombocytopenia were reviewed. Severe thrombocytopenia was defined as blood platelet counts (BPC) under 20 000/mm³, and patients were divided into 3 groups according to BPC at discharge: no response (NR), partial response (PR), complete remission (CR). The differences of clinical features, treatments, and prognosis were analysed.

Results Of the 131 patients, 70 cases were diagnosed as primary Sjögren’s Syndrome (pSS), 53 cases as SLE and 8 cases as other CTDs. 88.6% of them were female and the mean age of SLE patients was younger than pSS and other CTDs patients. The bleeding severity was negatively correlated with patients’ lowest BPC during hospitalisation. BPC at discharge was positively correlated with BPC during follow-up. There was no significant difference in basal data among NR, PR and CR group except serum IgG level that was lower in NR group than PR and CR group. The treatments were identical among the 3 groups, except that the use of IVIG was more frequently in CR group than the other 2 groups. Mortality in patients with partial or complete remission was significantly lower than in those without remission.

Conclusions Severe thrombocytopenia is more common in SLE and pSS patients than in other CTDs and high IgG level may predict a better efficacy. IVIG is helpful to achieve a full response and those unresponsive to the treatments at discharge have poor outcome.