Thrombocytosis, haemorrhagic pleural effusion and fibro-infiltrative patches with cavitary lung lesions in a child with COVID-19 pneumonia.

COVID-19 infection in children is relatively mild and is associated with fewer complications compared with adults. Here we report the case of a previously healthy preteen girl who presented with active COVID-19 and shock. On day 1, ultrasound of the thorax revealed a right-sided pleural effusion with haemorrhagic pus on diagnostic tap, which improved clinically with appropriate hospital treatment. Even at discharge, the chest X-ray barely changed, indicating a fibrotic area and a collapsed lung. The patient had persistent thrombocytosis, her inflammatory markers (C reactive protein, ESR, interleukin 6, serum ferritin, D-dimer and procalcitonin) were elevated, and a high-resolution CT scan of the thorax at discharge revealed fibro-infiltrative patches with cavitary lesions in COVID-19 pneumonia, which are unusual findings. The patient was discharged on clinical improvement and was doing fine on follow-up after 2 weeks.

Eltrombopag-Induced Thrombocytosis and Thrombosis in Patients With Antiphospholipid Syndrome and Immune Thrombocytopenic Purpura.

Antiphospholipid syndrome (APS) may be either as a primary or in association with an underlying systemic autoimmune etiology (36.2%), particularly systemic lupus erythematosus (SLE). Thrombocytopenia is infrequently observed in APS patients, with an occurrence of 22% to 42% with the frequency of thrombocytopenia, higher in APS and SLE combination than in primary APS. There have been some controversial reports regarding the treatment of APS syndrome with thrombocytopenia with TPO agonists. We like to report a case with APS syndrome with severe thrombocytopenia treated with TPO-RA and developed severe thrombocytosis and thrombosis. Our case represented the first case of TPO-RA in treating APS syndrome developed severe thrombocytosis and our case also concurred that use of TPO-RA agents should be strongly discouraged in APS until larger studies clarify the safety of TPO-RA agents in APS.

Clinical applications of thrombopoietin silencing: A possible therapeutic role in COVID-19?

Thrombopoietin (TPO) is most recognized for its function as the primary regulator of megakaryocyte (MK) expansion and differentiation. MKs, in turn, are best known for their role in platelet production. Research indicates that MKs and platelets play an extensive role in the pathologic thrombosis at sites of high inflammation. TPO, therefore, is a key mediator of thromboinflammation. Silencing of TPO has been shown to decrease platelets levels and rates of pathologic thrombosis in patients with various inflammatory disorders (Barrett et al, 2020; Bunting et al, 1997; Desai et al, 2018; Kaser et al, 2001; Shirai et al, 2019). Given the high rates of thromboinflammmation in the novel coronavirus 2019 (COVID-19), as well as the well-documented aberrant MK activity in affected patients, TPO silencing offers a potential therapeutic modality in the treatment of COVID-19 and other pathologies associated with thromboinflammation. The current review explores the current clinical applications of TPO silencing and offers insight into a potential role in the treatment of COVID-19.