Prevalence and clinical significance of antithyroid antibodies in children with immune thrombocytopenic purpura

Thyroid Dysfunction in Patients With Immune Thrombocytopenia: Prevalence and it's Impact On Outcome

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia with or without bleeding. Mild to moderate thrombocytopenia can be seen with thyrotoxicosis and hypothyroidism. This study was conducted to assess prevalence of thyroid dysfunction in ITP and impact on treatment and outcomes. This prospective study included patients more than 12 years old, diagnosed as ITP. Serum Thyroxine (T4) and Thyroid Stimulating Hormone levels and anti-thyroid peroxidase (TPO) antibodies were done by electro- chemiluminescence immunoassay. A total of 168 patients were enrolled, with thyroid function tests available in 146 patients. Mean age was 30.6 years, with 67.8% females (n = 114). Sixty percent patients had chronic ITP and 25% had persistent ITP. Overall prevalence of thyroid disease was 25.7% in the study population, with overt hypothyroidism seen in 21 (16.4%) patients, subclinical hypothyroidism in 9 (7.0%) patients and subclinical thyrotoxicosis in 3 (2.3%) patients, while no patient had overt thyrotoxicosis. Thyroid status of the patients did not correlate with duration of ITP or response to treatment. Presence of anti TPO antibodies was associated with abnormal thyroid function and chronic ITP. The prevalence of thyroid dysfunction is increased in ITP patients. Many such cases have anti TPO antibodies, suggesting autoimmune pathology. Role of glucocorticoids, estrogens and systemic illness in these findings must be further studied before firm conclusion can be drawn about their routine inclusion in diagnostic work up.

Seizures in myelin oligodendrocyte glycoprotein antibody-associated disorders and related immune factors

PURPOSE

Epileptic seizures in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorders (MOGAD) have been increasingly reported in the past two decades. However, the characteristics and possible mechanism largely remain unknown. This study aimed to investigate the clinical characteristics and immune mechanism of epileptic seizures in children with MOGAD.

METHODS

We conducted a retrospective single-center case-control study from February 2019 to February 2021. Clinical characteristics and immune parameters of enrolled patients with seizures (n = 12) in MOGAD (n = 32), as compared with the antibody-negative (n = 13) and control (n = 23) groups were then analyzed.

RESULTS

Seizures occurred in 24.5% (12/49, including cases that were not enrolled) of MOGAD. In this group, magnetic resonance imaging (MRI) abnormalities, especially unilateral cortical lesion and leptomeningeal enhancement, were more frequent in patients with seizures than in individuals without seizures (p < 0.05). Levels of thyroid peroxidase antibodies (TPOAb) in the seizure+/MOG+ group were significantly (p < 0.05) higher than those in the seizure-/MOG+ and control groups, whereas no significant differences as compared with the seizure+/MOG- group were observed. TPOAb level and brain MRI performance may be associated with disease course, since two cases with increased TPOAb and abnormal brain MRI were reported, after a second seizure attack occurred.

CONCLUSION

Unilateral cerebral cortical encephalitis and isolated seizures, especially in clusters and focal seizures, may be special phenotypes of seizures in MOG-AD. TPOAb may be associated with seizures in immune-related neurological diseases, but not a specific marker of MOGAD. Therefore, TPOAb may be considered but not strongly recommended to be monitored in MOGAD.

Insights on chronic immune thrombocytopenia pathogenesis: A bench to bedside update

Immune thrombocytopenia (ITP) is a heterogeneous disease with an unpredictable course. Chronicity can develop in up to two-thirds of adults and 20-25% of children, representing a significant burden on patients' quality of life. Despite acceptable responses to treatment, precise etiology and pathophysiology phenomena driving evolution to chronicity remain undefined. We analyzed reported risk factors for chronic ITP and associated them with proposed underlying mechanisms in its pathogenesis, including bone marrow (BM) microenvironment disturbances, clinical features, and immunological markers. Their understanding has diagnostic implications, such as screening for the presence of specific antibodies or BM examination employing molecular tools, which could help predict prognosis and recognize main pathogenic pathways in each patient. Identifying these underlying mechanisms could guide the use of personalized therapies such as all-trans retinoic acid, mTor inhibitors, FcRn inhibitors, oseltamivir, and others. Further research should lead to tailored treatments and chronic course prevention, improving patients' quality of life.

Chronic Immune Thrombocytopenia and Hashimoto's Hypothyroidism in an Adolescent: Presentation and Implications

Immune thrombocytopenia (ITP) is a disorder characterized by immune-mediated destruction of thrombocytes leading to peripheral blood platelet count of <100 × 10^9/L. Primary ITP is a terminology used in the absence of other causes or disorders that may be associated with thrombocytopenia, i.e., isolated thrombocytopenia. The term secondary ITP is used if such diseases coexist. We present here a case of a 14-year-old female diagnosed with immune thrombocytopenia. When her evaluation was not strongly supportive of primary ITP, she was screened and proved to have a concomitant Hashimoto thyroiditis. Contrary to the popular belief about secondary ITP in adult population, treatment of our patient's hypothyroidism did not improve her platelet's count, and the patient needed multiple immunosuppressive medications to improve her condition.

Primary immunodeficiencies, autoimmune hyperthyroidism, coeliac disease and systemic lupus erythematosus in childhood immune thrombocytopenia

AIM

To evaluate the cumulative prevalence of coeliac disease, systemic lupus erythematosus, autoimmune hyperthyroidism and primary immunodeficiencies in children with either newly diagnosed/persistent or chronic immune thrombocytopenia (ITP).

METHODS

Monocentric retrospective analysis of the clinical and biochemical features of 330 consecutive patients with ITP referred to our Pediatric Hematology Unit between January 2009 and December 2018.

RESULTS

The prevalence of systemic lupus erythematosus (0.3%), coeliac disease (0.3%) and autoimmune hyperthyroidism (0.6%) was not increased compared to general paediatric population. Of note, the prevalence of underlying primary immunodeficiencies was 2.4%, remarkably higher than the general paediatric population (P = .005). All the patients diagnosed with immunodeficiency developed either bi-/trilinear cytopenia or splenomegaly.

CONCLUSION

Whilst autoimmune and immunological screening is already recommended at the onset of immune thrombocytopenia, we recommend that primary immunodeficiencies be regularly screened during follow-up, especially in case of additional cytopenia or lymphoproliferation.

Association between acute disseminated encephalomyelitis and thyroid autoimmunity in children

BACKGROUND

Abnormal thyroid peroxidase antibody (TPOAb) levels are observed in various autoimmune diseases. However, the relationship between TPOAb and pediatric acute disseminated encephalomyelitis (PADEM) remains unclear. This study aimed to investigate the positive rate of TPOAb and thyroid dysfunction in children with acute disseminated encephalomyelitis (ADEM) and assess the relationship between TPOAb and clinical features of PADEM.

METHODS

This retrospective single-center case-control study was conducted from April 2017 to April 2019. We enrolled 23 children with ADEM and 23 age- and sex-matched healthy controls. Based on whether they were positive for TPOAb, the children with ADEM were allocated either to the TPOAb+ or TPOAb- group. The median follow-up time was 12 months (6-30 months). Observers were blinded to the patient groupings. We compared the clinical and imaging characteristics of the two groups.

RESULTS

Among the 23 patients with PADEM, 47.8% presented with abnormal TPOAb levels, while there were no TPOAb+ cases in the control group. Among the children with ADEM, there were significantly increased TPOAb positive rates and significantly decreased fT3 levels. TPOAb+ and TPOAb- subgroup analysis revealed significant differences in gait, fever, and total IgG. In the TPOAb+ group, there was a significant decrease in TPOAb levels at 2 weeks after ADEM onset. The follow-up of patients who were TPOAb+ at 3 months after onset showed a gradual decrease in their TPOAb levels back to normal. One patient who presented new nervous system symptoms after over 1 month also showed a simultaneous increase in TPOAb levels. There was a significant negative correlation between Glasgow Coma Scale (GCS) scores and TPOAb levels (p = 0.042, r = -0.892).

CONCLUSION

There was a negative correlation of TPOAb levels with GCS scores. Therefore, TPOAb levels could be used for the prognosis of patients with PADEM. We recommend determining thyroid function when assessing patients with PADEM during follow-up.

Latent and Overt Polyautoimmunity in Children and Adolescents With Immune Thrombocytopenia

Autoantibodies are biomarkers for autoimmune disease diagnosis, monitoring, and prediction. Therefore, this study established the frequency of latent and overt polyautoimmunity in children and adolescents with >6 months of diagnosis of immune thrombocytopenia (ITP). Forty-seven patients with chronic or persistent disease had non-organ-specific and organ-specific autoantibodies assessed. Frequency of latent polyautoimmunity was 36.2%, and, of overt polyautoimmunity, it was 4.3%. Of ITP patients with latent polyautoimmunity, 52.9% were positive for antinuclear antibody (ANA), 47.1% for autoantibodies other than ANA, and 64.7% for multiple autoantibodies. In addition, patients with latent polyautoimmunity and those positive for ANA were significantly older at disease onset. Both ITP patients positive and negative for autoantibodies reported family members with autoimmune diseases. The autoantibodies observed were as follows: ANA, anti-dsDNA, anti-SSA/Ro, IgM aCL, anti-GAD, anti-IA2, anti-IAA, anti-TG, anti-TPO, anti-LKM1, and SMA. Of ITP patients with overt polyautoimmunity, 1 was diagnosed with type 1 diabetes mellitus and the other with thyroiditis. In conclusion, children and adolescents with ITP present high frequency of latent and overt polyautoimmunity even for autoantibodies other than ANA. Therefore, ANA and other non-organ-specific and organ-specific autoantibodies should be considered for assessment during ITP patients' follow-up.

Markers of autoimmunity in immune thrombocytopenia: prevalence and prognostic significance

Prior studies have demonstrated an increased prevalence of autoimmune markers in patients with immune thrombocytopenia (ITP). Clinical experience has suggested that there may be an association between autoimmune markers and poor outcomes in ITP, but current guidelines do not encourage routine testing in these patients. We retrospectively assessed the prevalence of autoimmune markers in adult patients with ITP from our institutional database and used multiple logistic regression analyses to test for an association between autoimmune marker positivity and thrombotic events or clinical remission. We also assessed whether positivity for common autoimmune markers was associated with positivity for platelet autoantibodies. There was a high rate of autoimmune marker positivity in this population, with antinuclear antibody (65%), antithyroid peroxidase antibody (31%), and direct antiglobulin (29%) the most commonly found. Antithyroid peroxidase antibody positivity was associated with a lower probability of remission (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.09-0.79; P = .017). Lupus anticoagulant positivity was associated with a higher rate of thrombosis (OR, 8.92; 95% CI, 1.94-40.95; P = .005), and antinuclear antibody was strongly associated with thrombosis (P = .001). There was no relation between platelet autoantibody positivity and the presence of autoimmune markers. These results suggest that many patients with ITP have a state of immune dysregulation that extends beyond platelet autoantibodies and that certain autoimmune markers may be prognostically useful in this disorder.

Can Anti-Thyroid Antibodies Influence the Outcome of Primary Chronic Immune Thrombocytopenia in Children?

Background:

Immune thrombocytopenia (ITP) is an acquired immune mediated disorder characterized by isolated thrombocytopenia. Pediatric ITP patients can develop autoantibodies such as anti-thyroglobulin (TG) and anti-thyroperoxidase (TPO), even in the absence of clinical signs of autoimmune disease.

Objective:

The purpose of this article is to provide a review about: 1) the prevalence of positivity of anti-thyroid antibodies (TPO and TG) in pediatric patients with chronic ITP; 2) the role of autoimmune thyroiditis on the outcome of chronic ITP.

Method:

The authors individually completed a review of the literature for this article. Retrospective and prospective clinical studies with pediatric cohorts were considered.

Results:

From the analysis of data, we found 4 papers which included studies only on pediatric population, and which corresponded to selected criteria. Pediatric ITP patients have been shown to have a statistically significant prevalence of anti-thyroid antibodies over healthy controls (11.6-36% versus 1.2-1.3%). No correlation has been found between the platelet count and the prevalence of positive anti-thyroid antibodies at any time of the follow up.

Conclusion:

The results of our bibliographic research demonstrated that: a) pediatric patients with chronic ITP tend to have a statistically significant prevalence of anti-thyroid antibodies positivity respect to general pediatric population; b) there are no clear data about the role of autoimmune thyroiditis as prognostic factor for chronic course of ITP in pediatric age.

Immune Thrombocytopenia in an Adolescent with Hashimoto’s Thyroiditis – Case Report

Introduction: In childhood, thrombocytopenia caused by transient antibody-mediated thrombocyte destruction is most frequently diagnosed as immune thrombocytopenic purpura (ITP). We report the case of a girl with ITP associated with autoimmune thyroiditis.

Case presentation: A 11-year-old female patient with Hashimoto’s thyroiditis presented with clinical signs of petechiae and ecchymoses on the extremities. Laboratory tests showed remarkable thrombocytopenia with a platelet count of 44,500/μL, hence she was referred to a hematologic consultation. The peripheral blood smear showed normal size platelets in very low range. The bone marrow examination exposed hyperplasia of the megakaryocyte series with outwardly morphologic abnormalities. The patient was diagnosed with ITP, and her first-line treatment was pulsed steroid and immunoglobulin therapy. The thrombocytopenia was refractory to these first-line medications. After 6 months of corticotherapy and a period of severe menorrhagia, azathioprine immunosupression was initiated as a second-line treatment. Her platelet count rapidly increased, and the evolution was good, without bleeding complications.

Conclusion: In case of a medical history of autoimmune diseases and treatment-resistant ITP, attention must be focused on detecting coexisting autoimmune diseases and adjusting the treatment in accordance with the chronic evolution of the disease.

Role of antithyroid autoimmunity as a predictive biomarker of chronic immune thrombocytopenia

BACKGROUND

Immune thrombocytopenia (ITP) is an acquired immune-mediated disorder characterized by isolated thrombocytopenia. Pediatric ITP patients are prone to develop autoantibodies such as antithyroglobulin (TG) and antithyroperoxidase (TPO), even in the absence of clinical signs of autoimmune disease. The aim of this multicenter retrospective study was to evaluate (1) the prevalence of positivity of antithyroid antibodies (TPO and TG) in a large cohort of pediatric patients with chronic ITP; (2) the role of autoimmune thyroiditis as a prognostic factor for chronicity of ITP.

PROCEDURE

For this retrospective study, we collected data from patients diagnosed as affected by chronic ITP between 2011 and 2014 in six centers belonging to the Italian Association of Pediatric Haematology and Oncology (AIEOP).

RESULTS

From the analysis of data, we found a significantly higher prevalence of antithyroid antibodies in children with chronic ITP (11.6%) than in the pediatric population (1.2%-1.3%). No correlation has been found between the platelet count and the prevalence of positive antithyroid antibodies at any detection time of the study.

CONCLUSIONS

The results of our study demonstrated that (1) the prevalence of positivity for antithyroid antibodies (anti-TPO and anti-TG) in pediatric patients with chronic ITP results is significantly higher than in the pediatric population; (2) autoimmune thyroiditis does not seem to play a role as a prognostic factor for chronicity of ITP in pediatric patients.

Reliable assessment of the incidence of childhood autoimmune hemolytic anemia

BACKGROUND

Childhood autoimmune hemolytic anemia (AIHA) is a rare and severe disease characterized by hemolysis and positive direct antiglobulin test (DAT). Few epidemiologic indicators are available for the pediatric population. The objective of our study was to reliably estimate the number of AIHA cases in the French Aquitaine region and the incidence of AIHA in patients under 18 years old.

PROCEDURE

In this retrospective study, the capture-recapture method and log-linear model were used for the period 2000-2008 in the Aquitaine region from the following three data sources for the diagnosis of AIHA: the OBS'CEREVANCE database cohort, positive DAT collected from the regional blood bank database, and the French medico-economic information system.

RESULTS

A list of 281 different patients was obtained after cross-matching the three databases; 44 AIHA cases were identified in the period 2000-2008; and the total number of cases was estimated to be 48 (95% confidence interval [CI]: 45-55). The calculated incidence of the disease was 0.81/100,000 children under 18 years old per year (95% CI 0.76-0.92).

CONCLUSION

Accurate methods are required for estimating the incidence of AIHA in children. Capture-recapture analysis corrects underreporting and provides optimal completeness. This study highlights a possible under diagnosis of this potentially severe disease in various pediatric settings. AIHA incidence may now be compared with the incidences of other hematological diseases and used for clinical or research purposes.

The effect of anti-thyroid antibodies positivity on children with primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) is the most common cause of acquired thrombocytopenia in children. Anti-thyroid antibodies (aTA) have previously been found to be present in various autoimmune diseases. Our aim was to study the effect of aTA positivity (which are anti-thyroid peroxidase (aTPo) and/or anti-thyroglobulin (aTg)) on children with primary immune thrombocytopenia and their relation to treatment response. Sixty-one children with primary ITP were enrolled in the present study. They were further subdivided into: ND&P group (newly diagnosed and persistent) and chronic ITP group. Seventy-five apparently healthy children were enrolled as control group. aTPo and aTg antibodies were significantly higher and more frequently positive in all children with ITP and in each ITP group than the control group (P <.05 in all). But, there were no statistically significant differences between the two ITP subgroups (P >.05). aTA positive children with ITP had significantly lower platelet count: at the start of treatment (P =.009), after receiving methylprednisolone or intravenous immunoglobulin (P =.02) and at one month follow-up (P =.003) than aTA negative children with ITP. Lastly, aTA positive children had more relapses (P =.03), continued more frequently to have relapses after one year in the ND&P group (P =.02) and required immunosuppressive therapy more frequently in the chronic ITP group (P =.005).

Delayed Appearance of Cutaneous Lesions of Cutaneovisceral Angiomatosis (CAT) Leading to Misdiagnosis of Immune Thrombocytopenia

Cutaneovisceral angiomatosis with thrombocytopenia (CAT), also called multifocal lymphangioendotheliomatosis with thrombocytopenia (MLT), is a rare and newly described vascular malformation. Skin manifestations and thrombocytopenia are the hallmark of CAT/MLT, and visceral lesions are described. We report an infant with pulmonary hemorrhage, thrombocytopenia, and antiplatelet antibodies. There was no cutaneous involvement and the child was initially diagnosed with immune thrombocytopenia. Poor response to immune thrombocytopenia-directed therapy raised suspicion for an alternative diagnosis, and the ultimate diagnosis of CAT/MLT was made by lung tissue sampling. Unexpectedly, 2 years after resolution of pulmonary lesions and thrombocytopenia, the child developed typical cutaneous lesions.

Clinical practice: immune thrombocytopenia in paediatrics

Immune thrombocytopenia (ITP) is a disease affecting both children and adults. It is defined as acquired isolated thrombocytopenia caused by the autoimmune production of anti-platelet antibodies. Childhood ITP most frequently occurs in young children who have been previously well, although a viral respiratory tract infection often precedes thrombocytopenia. A benign and self-limiting course is common, but major bleeding complications such as intracranial haemorrhage may occur. Yet one cannot predict which child will have a prolonged course of thrombocytopenia and who will develop an intracranial haemorrhage. In children without atypical characteristics, only minimal diagnostic investigations are needed, and most paediatric ITP patients do not need platelet-enhancing therapy even though various treatment options are available. A "watch and wait" strategy should be considered in paediatric patients with mild disease. Steroids, intravenous immunoglobulin G or anti-D immunoglobulin are the current first-line therapeutic measures for children at risk for severe bleeding. When life-threatening bleeding occurs, a combination of therapies is needed. In this review, we summarise the current knowledge on primary ITP in children and adolescents.