Abstract:
Immunological Thrombocytopenic Purpura or ITP is the most common benign
blood disease in pediatrics.
The aim of this work is to analyze the epidemiological, clinical,
paraclinical and etiological profile of Primary and secondary immune
thrombocytopenia.
It is a retrospective study over a period of four years from September
2017 to September 2021, collecting all cases of immunological
thrombocytopenic purpura hospitalized in hematology pediatric unit at
the Abderrahim Harouchi Children’s Hospital in Casablanca.
135 patients with ITP were hospitalized in this period including 76 boys
(56.3%) and 59 girls (43.7%). The average age was 5.8 years (1 month
-14 years). According to Buchanan bleeding score, 3.4% of the patients
were grade 0, 9.6%, were grade 1 and 39.2% of the patients were grade
2, 41.5 % of the patients were grade 3, 5% in grade 4 and only 1 case
was in grade 5. Etiologically, 86% of primary ITP and 14% of secondary
ITP were recorded. The etiological assessment revealed 9 cases of
Helicobacter pilori infection, 6 cases of immune deficiency (5 cases of
WISKOTT ALDRICH and 1 case of ALPS) and4 probable cases of systemic
lupus erythematosus.
Patients were treated with either corticosteroids or intravenous
immunoglobulin (IgIV). The trend was towards acute ITP in 85 cases
(63%), persistent and chronic ITP in 50 cases (37%).
For a better management of chronic and persistent ITP a complete
etiological assessment is essential. This will allow to propose an
etiological treatment and therefore an improvement of thrombocytopenia.
Keywords: primary immune thrombocytopenia, secondary immune
thrombocytopenia, child, wiskott Aldrich syndrome, helicobacter
infection.
INTRODUCTION
Immune thrombocytopenic purpura (ITP) is the most common benign
hemopathy in pediatrics, it is defined as an acquired autoimmune
bleeding disorder with a low platelet count, usually, less than 100,000
in the presence of a generalized petechial rash, bruising, or bleeding
in an otherwise healthy child [1].The incidence of ITP ranges from
1.1 to 6.4 cases per 100,000 children-years with peak in childhood (age
1–5 years) [2,3]. There is a slight predominance in males than
females [4].
The classification of ITP depends on the duration of disease based on
the following definitions: newly diagnosed (from diagnosis to three
months), persistent (3-12 months), and chronic (after 12 months)
[3,5]. Chronic ITP is seen in 10 to 25% of these patients with a
prevalence estimated as 9.5 to 11.2 per 100,000 persons year [3].
The ITP etiology should be sought in the presence of a recurrent or
chronic ITP. Most cases are considered idiopathic and labelled as
‘primary ITP’, whereas approximately 20% of ITP cases are associated
with an underlying disorder and are labelled as ‘secondary ITP’[3].
This secondary ITP can be due to infection with a number of agents,
including hepatitis C virus (HCV), human immunodeficiency virus (HIV),
and Helicobacter pylori. Other causes include underlying autoimmune and
lymphoproliferative disorders such as systemic lupus erythematosus,
Wiskott-Aldrich syndrome, and common variable immunodeficiency, as well
as drugs such as trimethoprim-sulfamethoxazole [3].
The ITP patients are usually treated with steroids or immunoglobulin as
a first line treatment. For chronic ITP the traditional therapies are
rituximab and splenectomy [3]. Mortality from ITP in children is
rare and mainly due to complications from catastrophic bleeding,
specifically intracranial hemorrhage [1]. The disease is
self-limiting in a large proportion of patients, and 75% to 90% of
children will recover spontaneously within 6 to 12 months [2,6].
The aim of this retrospective study is to highlight the frequency of
secondary ITP among ITP patients, to precise the specificities of theses
patients, and to determine the etiological profile of the ITP in
children.
MATERIALS AND MEHODS
In this retrospective study, 135 ITP patients admitted in
Hematology-oncology unit in pediatrics 3 Department, A. HAROUCHI
University Hospital, Casablanca, Morocco, between September 2017 and
September 2021 were included. Patients were included in this study if
their age at diagnosis was less than15 years, and their platelet count
was low (less than 100 000/mm3). Exclusion criteria included the
following: the presence of mild splenomegaly and having received
treatment that may cause drug-induced thrombocytopenia. The demographic
and clinical characteristics of patients at the initial diagnosis of ITP
were abstracted from their medical records. These data included age,
gender, initial platelet count, initial presentation of mucocutaneous
purpura.The bleeding was assessed using the BUCHANAN score (grade 0,
grade 1, grade 2, grade 3, grade 4 and grade 5). Patients were graded
based on their medical history or a physical examination completed at
the time of the appointment. Grade 1 is few bruises and petechiae. Grade
5 is life threatening hemorrhage. Furthermore, data about the need for
treatment of ITP and the response to treatment were collected. The
screening for antinuclear antibody (ANA), hepatitis C virus (HCV),
hepatitis B virus (HBV), human immunodeficiency virus (HIV),
immunoglobulin dosage and lymphocyte phenotype were tested in the
patients with chronic ITP. The H. pylori stool antigen test or the urea
breath test were used to screen patients for H. pylori were abstracted
from the medical records.
RESULTS
A total of 135 children who were diagnosed with ITP at our unit between
September 2017 and September 2021 and were included in this study. Their
age at diagnosis ranged between 1 month and 14 years, with a mean of
5,8. There were 76 boys (56.3%) and 59 girls (43.7%). According to
Buchanan bleeding score, 3.4% of the patients (5 cases) were grade 0,
9.6% (13 cases), were grade 1 and 39.2% of the patients (53 cases)
were grade 2, 41.5 % of the patients (56 cases) were grade 3, 5% in
grade 4 and only 1 case was in grade 5.
116 patients (86%) were diagnosed as having primary ITP and 19 (14%)
were considered to have secondary ITP because the ITP was associated
with another underlying disorder or condition. Among the 135 children,
85 patients (62.9%) had an acute ITP and 50 patients (37%) had a
chronic ITP. In these chronic ITP, a concurrent immune disease was
observed in 19 (38%) patients who were diagnosed with secondary ITP. Of
those who were diagnosed with secondary ITP, 6 (31,5%) had primary
immune deficiency and 4 (21%) had systemic lupus erythematosus. The 9
remaining patients (47.3%) had a helicobacter infection. All patients
were tested for the presence of HCV, HBV, and HIV, and none tested
positive. In patients with primary immune deficiency we found 5 cases of
Wiskott Aldrich syndrome. All these patients had thrombocytopenia,
eczema and recurrent infections.
Table 1 shows the characteristics of patients with primary and secondary
ITP. Patients with secondary ITP were slightly younger than patients
with primary ITP. The mean age was 6 years for patients with primary ITP
and 5.4 years for patients with secondary ITP. Among patients with
secondary ITP, the mean age of patients with a primary immune deficiency
(mean: 3.7 years) was lower than that for patients with other disorders
(mean: 6.5 years). At the time of diagnosis, 74% of patients with
secondary ITP and 62% patients with primary ITP had an initial platelet
count >30 109 /L. Among patients with secondary ITP, the
median initial platelet count for patients with a primary immune
deficiency was slightly higher (34 109 /L) than that for patients with
other disorders (23 109 /L). At the time of diagnosis, the Buchanan
bleeding score was higher than 2 in 48 % of patients with primary ITP
and in 37% of patient with secondary ITP. The two groups had poor
response to corticosteroid treatment (less than 20% had good response).
However, the primary ITP patients had good response to immunoglobulin in
55% of cases versus 14,8% of good response in the secondary ITP
patients.
Table 1. Clinical, laboratory characteristics and response of treatment
of the whole cohort of 143 patients