Background: Systemic lupus erythematosus (SLE) has various presentations in children. Hematologic abnormalities is common in childhood onset of SLE, however, isolated thrombocytopenia is relatively rare. Thus, we present a child with isolated thrombocytopenia as a rare presentation of SLE.

 Case presentation: A 12-year-old boy with chief complaints of loss of appetite, weight loss, decreased platelet count (8000/µL) and lymph node enlargement was referred to our hospital. Biopsy of lymph node showed reactive lymphadenopathy. Investigations regarding infectious disease was negative. Platelet count remained low after low dose steroidned therapy. Antinuclear antibody (ANA) and anti-double stranded DNA antibody screening tests were positive with titer of 1/62 and 1/54, respectively. Therefore, juvenile SLE was considered as the final diagnosis and raising the dose of prednisolone to 2mg/kg/day was associated with increasing platelet count to 40000/µL and a week later to 96000/µL.

 Conclusion: The findings of this study indicate that in cases with isolated thrombocytopenia refractory to conventional dose of steroids, SLE should be considered. This study justifies serum ANA and anti DNA assessment in children with thrombocytopenia