Safety of anti‐SARS‐CoV‐2 vaccination for patients with immune thrombocytopenia

Abstract

Severe coronavirus disease 2019 , due to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), may be associated with mild thrombocytopenia, 1,2 and some COVID-19-induced immune thrombocytopenia (ITP) cases have been reported. 3,4 Some reports suggest that patients with pre-existing ITP may experience a relapse 5 in the case of SARS-CoV-2 infection that could be prevented by vaccination. However, a growing number of de novo ITP occurring after anti-SARS-CoV-2 vaccination are being reported with mRNA-based vaccines. In a recent series, 6 20 patients who received either BNT162b2 (Comirnaty â ) or mRNA-1273 (SpikeVax â ) vaccines had new-onset thrombocytopenia after the first injection (median time: 5 days), usually associated with bleeding and low platelet counts (median: 2 9 10 9 /l). The incidence of vaccine-induced thrombocytopenia remains difficult to assess precisely as no routine blood count is recommended after vaccination. However, it appears very low, with >20 million people vaccinated in the United States with at least one dose at the time this paper 6 was submitted. However, whether patients with ITP have a risk of relapse after anti-SARS-CoV-2 vaccination remains a matter of debate. In France, the National Reference Centre for Adult Immune Cytopenia proposed that anti-SARS-CoV-2 vaccination should be considered in patients with ITP and that a platelet count should be obtained 1 week after each vaccine injection in order to detect ITP relapse. In the present study, we assessed the evolution of a cohort of patients with ITP that received anti-SARS-CoV-2 vaccination.We conducted an observational study in four French referral centres from January 2021 to June 2021. Inclusion criteria were patients aged >18 years with a previous ITP diagnosis (primary or secondary) according to international criteria 7 and receiving at least one anti-SARS-CoV-2 vaccine injection. All these patients were already enrolled in the prospective CARMEN-France registry and were not opposed to real-world data collection about ITP management. All clinical and biological data used in the present study were already recorded in the registry (authorisation number 2012-438 from the French national agency regulating data protection).From January to June 2021, 92 adult patients with ITP (55 women, 59Á8%), with a median [interquartile range (IQR), range] age of 69 [19, years (Table SI) were selected. In all, 78 patients had primary ITP (85%), and two had a history of COVID-19-associated ITP 1 year previously. At the time of first vaccine dose, the median (IQR, range)

COVID-19 vaccination in patients with immune thrombocytopenia

“…In contrast, a study of 92 ITP patients who mostly received the BNT162b2 vaccine, did not observe decreased platelet count after first and second vaccination. 12 In our mixed-effects model, we did observe a significant decrease of platelet counts of 6.3% in ITP patients after COVID-19 vaccination. As there is a high degree of interand intra-individual variability in platelet counts over time, we systemically measured patients over a longer observation period and corrected for inter-and intra-individual variability.…”

“…Other observational studies found comparable incidences between 12 to 25%. [11][12][13] . The amount of patients needing rescue medication was 6.9% in our study compared to 8.7% in the study of Crickx, et al 12 In other autoimmune diseases, exacerbation of symptoms after COVID-19 vaccination has anecdotally been described, with rapid remission after glucocorticoids.…”

“…[11][12][13] . The amount of patients needing rescue medication was 6.9% in our study compared to 8.7% in the study of Crickx, et al 12 In other autoimmune diseases, exacerbation of symptoms after COVID-19 vaccination has anecdotally been described, with rapid remission after glucocorticoids. 19,20 However, in a single center study of 26 patients with chronic inflammatory diseases, no patients experienced disease flare.…”

“…Exacerbation of thrombocytopenia in ITP patients after COVID-19 vaccination has been described in retrospective studies, but a systematic evaluation of platelet counts over time is missing. [10][11][12][13] Therefore, it is still unclear how COVID-19 vaccination affects ITP patients over time, if and when thrombocytopenia develops and when they are at risk for bleeding.…”

Coagulopathy and Fibrinolytic Pathophysiology in COVID-19 and SARS-CoV-2 Vaccination

“…Risk factors for ITP relapse with vaccination include ongoing treatment, old age [ 164 ], and post-splenectomy status or a long history of prior treatment [ 165 ]. In terms of platelets, low platelet counts are reportedly associated with a higher risk of relapse [ 164 ], and platelet counts often decrease rapidly in patients with normal platelet count [ 166 ]. Regardless of the platelet count, attention should be paid to transition of the platelet count in ITP patients.…”