Recurrent immune thrombocytopenia: case reportA 23-year old woman developed recurrent immune thrombocytopenia (ITP) following administration of COVID-19-Vaccine-Pfizer-BioNTech.The woman was diagnosed with ITP at the age of 14 years. Thereafter, she received high-dose immunoglobulins and her platelet count was normalised. One year later, she presented with recurrent ITP. She received 4 consecutive daily infusions of high-dose immunoglobulins and a temporary platelet count recovery was observed. One month later, her platelet counts rapidly decreased. Subsequently, prednisone was started; however, her symptomatic thrombocytopenia persisted with recurrent epistaxis and metrorrhagia. Thereafter, rituximab was administered. The platelet count returned to normal after a year and remained in the normal range. When a new ITP recurrence was observed, again it was successfully treated with high-dose immunoglobulins. Immunosuppressive treatment with mycophenolate was started with a complete platelet count recovery. In December 2020, her mother and grandmother developed a life-threatening SARS-CoV-2 pneumonitis. She tested negative for SARS-CoV-2 infection detected by real-time polymerase chain-reaction (RT-PCR) assay. She had a complete ITP remission for 3 years and still she was on mycophenolate treatment. She received the first dose of the of COVID-19-Vaccine-Pfizer-BioNTech [Pfizer-BioNTech SARS-CoV-2 vaccine; dosage and route not stated] on March 20, and the second dose on 10 April 2021. Fifteen days after receiving the second dose of vaccine, peripheral blood control showed a decreased platelet count. Her treatment with mycophenolate was continued, and low-dose prednisone was added. One week later, she was admitted to emergency room with severe headache, metrorrhagia, and cutaneous haemorrhages. She was not taking any medications other than mycophenolate and prednisone. A complete blood count revealed severe thrombocytopenia with normal leucocytes and red cells indices. The peripheral blood film did not reveal platelet clumping or SC histocytes. Her coagulation profile, renal and liver functions were normal. Brain CT ruled out the presence of haemorrhages and Chest-X-ray was normal. A viral serological tests, blood cultures and urine analysis were negative for active infections.The woman received high-dose immunoglobulins for two subsequent days and prednisone an continued on mycophenolate. Her platelet counts slowly increased in five weeks. Prednisone was tapered and discontinued in 4 weeks. After 3 months, her platelet count recovered. She had ITP remission with a normal platelet count and continued on mycophenolate therapy.