Abstract Number: PB1241
Meeting: ISTH 2020 Congress
Background: Immune thrombocytopenia (ITP) is the most common cause of thrombocytopenia in children and adolescents. Most cases are considered primary, but others are secondary to coexisting conditions. The occurrence of secondary ITP has been estimated based on clinical experience of experts and short series (around 20%), but there is a lack of data regarding its incidence in our country.
Aims: To study the incidence and outcome of secondary ITP in a large cohort of pediatric Spanish patients.
Methods: A retrospective observational study was conducted in two pediatric University hospitals in Spain between 2009 and 2019, which included children from 4 months to 18-year-old diagnosed with ITP. Data were recorded from clinical charts: gender, age at diagnosis, coexisting condition and associated characteristics (at diagnosis or during the follow-up), outcome and treatment.
Results: A total of 442 patients were diagnosed with ITP during the period study. Mean age was 5.4 (SD 4.4); a 49.1% were boys. Most of them (n=284; 64.3%) were catalogued as newly diagnosed ITP, 55 (12.4%) as persistent ITP, and 102 (23.1%) as chronic ITP.
Secondary ITP was diagnosed in 78 cases (17.4 %). Clinical characteristics and outcome depending on coexisting conditions are shown in table 1 and figure 1. Apart from them, there are 10 chronic ITP patients under suspicion of an underlying autoimmune disease or immunodeficiency.
Conclusions: Characteristics of our cohort are comparable to that describe in the literature. Secondary ITP identification is important as it predicts outcome. Whereas most of secondary ITP are diagnosed at onset (especially those secondary to vaccines or infections), others like autoimmune diseases or immunodeficiencies should be rule out periodically as they are usually diagnosed later, even years after or later of ITP onset. An early diagnosis of the underlying disease could have an impact on choosing a tailored treatment.
[Cumulative incidence of remission depending on the underlying diagnosis of secondary ITP]
| Coexisting condition | n | Age ITP onset. Mean (SD) | Gender | Age at diagnosis of coexisting condition. Mean (SD) | Clinical characteristics, observations and treatment administered |
| Vaccines | 21 | 3.8 (4.3) | F: 12 M: 9 | At onset | -Most of them received IVIG -Two cases of persistent ITP -Two cases of chronic ITP (suspicion of CVID in one case) |
| Viral infection | 26 | 6.7 (5.0) | F: 15 M: 11 | At onset | -VEB: 12; CMV: 7; Parvovirus: 1; Others: 6 -Most of them (n=15) received IVIG -Persistent ITP: 3 cases. Chronic ITP: 4 cases. |
| Immunodeficiency: CVID | 7 | 10.8 (3.8) | F: 5 M: 2 | 13.7 (3.7) | -All cases of CVID are in remission after receiving substitutive IVIG. Four of them also received immunosuppressive treatment (MMF and sirolimus). |
| Immunodeficiency associated to other syndromes | 6 | 9 (5.7) | F: 3 M: 3 | At onset | -DiGeorge and one Kabuki sd patients received TPO analogs. -Down sd. patients are in remission. |
| EVANS | 4 | 9 (5.4) | F: 3 M: 1 | 10.6 (3.3) | -Three patients received immunosuppressive treatment (MMF). -Underlying ALPS in one case. |
| Autoinmunity | 11 | 10 (3.06) | F: 9 M: 2 | 12.2 (3.0) | -Five patients in complete remission after receiving specific treatment: hydroxychloroquine +/- glucosteroids. -Four patients are under treatment with TPO analogs and specific treatment -One patient in complete remission after receiving rituximab (refractory to other treatments, corticodependent) |
| Others | 3 | 13 (5.0) | F: 1 M: 2 | At onset | -Chemotherapy (2) and cotrimoxazole (1) -All in CR after avoiding the cause. |
[Secondary conditions of ITP, clinical characteristics and treatment administered.]
To cite this abstract in AMA style:
Berrueco Moreno R, Sebastian E, Solsona M, González de Pablo J, Ruiz-Llobet A, Sevilla J. Secondary Immune Thrombocytopenia in Children: Characteristics and Outcome of a Large Cohort from Two Spanish Centers [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/secondary-immune-thrombocytopenia-in-children-characteristics-and-outcome-of-a-large-cohort-from-two-spanish-centers/. Accessed December 6, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/secondary-immune-thrombocytopenia-in-children-characteristics-and-outcome-of-a-large-cohort-from-two-spanish-centers/