Presence of thyroid abnormalities in children with systemic lupus erythematosus

Technetium-99m thyroid scan; does it have a diagnostic aid in sub-clinical auto-immune thyroid disease in systemic lupus erythematosus patients?

PURPOSE

Technetium-99m (Tc-99m) thyroid scintigraphy is a well known diagnostic tool that shows the entire gland in a single image. We aimed to evaluate its additive diagnostic value in subclinical autoimmune thyroid disease (S-AITD) in systemic lupus erythematosus (SLE) patients.

METHODS

We investigated 100 systemic lupus erythematosus (SLE) patients without overt thyroid involvement (eight men and 92 women; mean age 40±6.5 years) and 50 age and sex matched controls. All were subjected to thyroid evaluation using anti-thyroglobulin (anti-TG) and anti-thyroid peroxidase (anti-TPO) antibodies; hormones (FT3; FT4 and TSH) and Tc-99m thyroid scintigraphy.

RESULTS

14/100 (14%) and none (0%) were positive for S-AITD in SLE and control groups, respectively (P = 0.0001). They were classified by thyroid scintigraphy and hormonal profile into 2/14 Hashimoto; 10/14 atrophic thyroiditis and 2/14 Graves' disease. Anti-TPO was elevated in 12 SLE cases, while anti-TG was elevated in only 2/14 (P = 0.0001). Thyroid scintigraphy showed statistically significant associations with FT4, TSH and anti-TPO.

CONCLUSION

Tc-99m thyroid scintigraphy may have an additional diagnostic role in S-AITD among SLE patients, with an impact on patient management. This potential needs to be further evaluated in a larger series on a multicenter basis.

The spectrum of thyroid disorders in systemic lupus erythematosus

To study the spectrum of thyroid disorders in systemic lupus erythematosus (SLE). Hundred SLE patients as per American Rheumatology Association(ARA) classification criteria underwent clinical examination, including assessment of disease activity (SLEDAI) and laboratory evaluation for serum triiodothyronine (T3),free thyroxine (FT4), thyroid stimulating hormone (TSH), antithyroperoxidase (TPO) antibody and antithyroglobulin (TG) antibody. Hundred age- and sex-matched apparently healthy individuals served as control. Thirty-six (36%) lupus patients had thyroid dysfunction when compared to 8 (8%) of controls and all of them were women. Primary hypothyroidism was the commonest dysfunction in 14 (14%), while subclinical hypothyroidism and subclinical hyperthyroidism was seen in 12 (12%) and 2 (2%), respectively. Eight (8%) had isolated low T3 consistent with sick euthyroid syndrome. Eighteen (50%) of thyroid dysfunction were autoimmune in nature (autoantibody positive) and rest 18 (50%) were non-autoimmune. Euthyroid state with the elevation of antibodies alone was seen in 12 (12%) of the lupus patients. In contrast, only 5 (5%) of controls had primary hypothyroidism and 3 (3%) had subclinical hypothyroidism, while none had hyperthyroidism. SLEDAI score and disease duration were compared between lupus patients with thyroid dysfunction to those with normal thyroid function. A statistically significant association was found between SLEDAI and thyroid dysfunction of sick euthyroid type.SLE disease duration had no statistically significant association with thyroid dysfunction. Prevalence of thyroid autoantibodies in lupus patients was 30% when compared to 10% of controls. Ninety-six (96%) of the SLE patients were ANA positive, while 4 (4%) of them were ANA negative but were anti-Sm antibody positive. There were no suggestions of any other autoimmune endocrine diseases like diabetes or Addison's disease (clinically and on baseline investigations) in our lupus cohort and hence no further work up was done for these diseases. Thyroid disorders are frequent in SLE and are multifactorial with a definite higher prevalence of hypothyroidism as well as thyroid autoantibodies.

Pediatric lupus--are there differences in presentation, genetics, response to therapy, and damage accrual compared with adult lupus?

Some complement deficiencies predispose to systemic lupus erythematosus (SLE) early in life. Currently, there are no known unique physiologic or genetic pathways that can explain the variability in disease phenotypes. Children present with more acute illness and have more frequent renal, hematologic, and central nervous system involvement compared to adults with SLE. Almost all children require corticosteroids during the course of their disease; many are treated with immunosuppressive drugs. Mortality rates remain higher with pediatric SLE. Children and adolescents accrue more damage, especially in the renal, ocular and musculoskeletal organ systems. Conversely, cardiovascular mortality is more prevalent in adults with SLE.

[Thyroid disorders and childhood rheumatic diseases]

INTRODUCTION

The relationship between thyroid dysfunction and autoimmune diseases has mainly been described in adults. The aim of this study was to analyse the prevalence and characteristics of thyroid abnormalities in children with rheumatic diseases.

PATIENTS AND METHOD

One hundred and forty-five patients (109 girls and 36 boys) from a rheumatology paediatric unit were studied for two years. The diagnoses were: juvenile idiopathic arthritis (JIA) (n=115), lupus (n=17), juvenile dermatomyositis (n=5), scleroderma (n=4), and one case each of the following: mixed connective mixed disease, CINCA syndrome (chronic infantile neurological, cutaneous and articular), TRAPS (tumour necrosis factor receptor-associated periodic syndrome), and familial mediterranean fever. T4 and TSH levels were carried out, and if these showed abnormalities, antithyroid antibodies (ATA) were determined.

RESULTS

Six girls aged between 2 and 17 years old had thyroid abnormalities. Three had JIA and three had lupus. Five were diagnosed with autoimmune hypothyroidism, with high ATA levels, and there was one case of hyperthyroidism. All of the patients with thyroid dysfunction had positive antinuclear antibodies (ANA), compared to 34.5% of the rest of the patients (p=0.003).

CONCLUSIONS

The prevalence of thyroid abnormalities in children with rheumatic disease was 4.14% to 7.9% in JIA patients with positive ANA, and up to 17.6% with lupus. The majority of patients were asymptomatic. Thyroid hormones should be determined when rheumatic disease is diagnosed and periodically afterwards.

Association lupus systémique et hypoparathyroïdie : à propos d’un cas

Hypoparathyroidism is very rarely diagnosed in patients with lupus.

CASE

A 39-year-old women had systemic lupus erythematosus known for 3 years. She was admitted for a paresthesia of the lower limb, depression, insomnia and 5 kg weight loss. The laboratory tests revealed hypoparathyroidism and no sign of disease activity. Treatment with oral calcium and vitamin D resulted in correction of the hypocalcemia and QT prolongation.

DISCUSSION

The combined diagnosis lupus-hypoparathyroidism has very rarely been reported. We suggest there may be a common underlying pathological process linking the two diseases. The occurrence of these diseases in the same individual may be related to an underlying genetic predisposition or secondary to the generalized autoimmune disease process.

Systemic lupus erythematosus

Systemic lupus erythematosus in children and adolescents is a multisystem autoimmune disease with a great variability in disease presentation and course. This article summarizes available epidemiologic data, clinical patterns, approaches to investigation and treatment, and recent outcome data.

Effect of maternal autoantibodies on fetal cardiac conduction: an experimental murine model

The pathogenesis of congenital heart block (CHB) remains unclear. The occurrence rate of neonatal CHB is low, even in murine models of lupus erythematosus. The assessment of heart block in murine maternal lupus models by measuring atrioventricular conduction in neonatal offspring is potentially confounded by fetal wastage. We therefore sought to develop a murine CHB model with a superior immune response and to use embryonic Doppler echocardiography to observe conduction system damage in the fetus. Mature 8-wk-old female C3H/HeJ mice (n=43) were immunized with 60 kD Ro, 48 kD La, or recombinant calreticulin autoantigens. ELISA confirmed that significant serum autoantibodies developed in all three immunized groups when compared with controls. Starting at 13 d of gestation, a significantly lower fetal heart rate (HR) and a higher percentage of fetal bradycardia/atrioventricular block (AVB, nonadvanced second degree) were observed in all immunized groups, compared with controls. There was 9-18% nonadvanced second-degree AVB in immunized groups and 0% in controls at <18 d of gestation. Neonatal electrocardiograms demonstrated only 1 degrees AVB in immunized groups. Maternal immunization with 60 kD Ro, 48 kD La, or recombinant calreticulin autoantigens resulted in AVB in a significant percentage of fetuses, however, lesser degrees of AVB were seen at birth. Significant fetal bradycardia and AVB may be missed by assessment only at birth in murine models of CHB due to fetal wastage.

[Childhood-onset systemic lupus erythematosus]

Systemic Lupus Erythematosus (SLE) remains a challenging autoimmune disease in term of etiology, pathogenesis and treatment. It is estimated that 10-17% of lupus patients present before the age of 16. SLE in children appears to have more severe organ involvement than in adults. The outcome of childhood SLE has improved during the last decade, but the morbidity remains high.

Systemic lupus erythematosus in childhood

Systemic lupus erythematosus is a disease of immune dysregulation that strikes approximately 1 in 2000 individuals. The usual patient is a young woman of child-bearing age; however, this illness affects patients of all ages, ethnic backgrounds, and both sexes. Twenty percent of all cases of lupus are diagnosed during the first two decades of life. Perhaps the most essential point in treating a child with lupus is to be aware and concerned about how to deliver treatment to a patient in the middle of their physical, intellectual, and emotional development.

Autoimmune thyroid disorders in juvenile chronic arthritis and systemic lupus erythematosus

The appearance of autoimmune thyroiditis in the course of other autoimmune diseases, which do not affect specific organs (systemic lupus erythematosus, Sjögren syndrome, rheumatoid arthritis and others), is more frequent than is usually believed. Nevertheless, it is scarcely studied, especially in children. The purpose of this study was to look for autoimmune lesions of the thyroid gland in children suffering from juvenile chronic arthritis (JCA) and systemic lupus erythematosus (SLE). Twenty seven children having JCA and twelve children with SLE, aged 5 to 18 years, were enrolled into study. In all of them the disease was in an active phase. The serum levels of total thyroid hormones (T3, T4) and TSH, thyroid antibodies (TAB and MAB) and antinuclear antibodies (ANAB) were analyzed using respectively fluoroimmunologic, microhemagglutination and indirect immunofluorescention tests. According to our results, autoimmune thyroiditis was found in 12 out of 27 children with JCA (44.4%); 85.2% of them were euthyroid, 11.1% had a compensated hypothyroidism, and 3.7% had Hashi-toxicosis. From a clinical point of view, very interesting was the combination of JCA, autoimmune thyroiditis and pseudoxanthoma elasticum in a 13-year old girl. Positive thyroglobulin antibodies (1:80-1:5120) were found in 17 out of 27 cases of JCA (63%). The microsomal antibodies were elevated (1:100-1:1600) in 7 out of 27 (25.9%); antinuclear antibodies (1:80-1:640) were detected in 15 out of 27 cases of JCA (55.5%). A simultaneous elevation of all three kinds of antibodies was found in 14.8% of children with JCA, and of TAB and MAB--in 18.5%. Thyroid gland disorders were detected also in children suffering from SLE. Thyroglobulin antibodies were positive (1:80-1:5120) in 7 out of 12 cases. Antinuclear antibodies (1:320-1:2560) were detected in 8 out of 12 cases (66.7%). The serum levels of T3, T4 and TSH were in the reference limits in all children with SLE. The present study suggests that involvement of the thyroid gland is not uncommon in autoimmune disease in Autoimmune thyroiditis can occur in association with other autoimmune diseases, affecting some organs or systems, such as the insulin-dependent diabetes mellitus, pernicious anaemia, thrombocytopenia, vitiligo, as well as some chromosomal aberrations--Turner's syndrome, Noonan's syndrome and Down's disease [1]. The appearance of autoimmune thyroiditis together with other autoimmune diseases which do not affect specific organs (such as systemic lupus erythematosus, Sjögren syndrome) is the reason to classify them in a common subgroup of the autoimmune polyendocrine syndromes--type IIID [2]. The rheumatic diseases are--more frequently than suspected--associated with autoimmune thyroiditis, but this connection is not well studied. The literature offers very scarce information on the problem, especially for the childhood. The purpose of this study was to look for autoimmune lesions of the thyroid gland in children suffering from juvenile chronic arthritis (JCA) and systemic lupus erythematosus (SLE).