Childhood vitiligo and thyroid disease

Abstracts

A associação entre vitiligo e tireoidopatia na criança é discutível. Cinquenta crianças com vitiligo e 40 sem vitiligo foram submetidas às dosagens séricas de anticorpos antitireoide e hormônio tireoestimulante. Um caso (grupo teste) e um caso controle mostraram títulos de TSH acima do limite normal; o vitiligo não representou maior risco para tireoidopatia.

Anticorpos; Criança; Glândula tireoide; Tireotropina; Vitiligo

COMMUNICATION

Childhood vitiligo and thyroid disease

Nurimar Conceição Fernandes^I; Márcia Maria Cajueiro Campos^II

^IAssociate Professor, School of Medicine, Universidade Federal do Rio de Janeiro. Instituto de Puericultura e Pediatria Martagão Gesteira. Hospital Universitário Clementino Fraga Filho – Rio de Janeiro (RJ), Brazil

IIMedical Graduate Studies (concentration: Dermatology), School of Medicine, Universidade Federal do Rio de Janeiro – Rio de Janeiro (RJ), Brazil

Mailing Address

ABSTRACT

The association of vitiligo / thyroid disease in childhood is debatable; 50 children with vitiligo and 40 without it were submitted to serum dosage of antithyroid antibodies and thyrostimulating hormone. One case (test group) and one control showed a serum titer of TSH above the normal limit; vitiligo did not represent a greater risk for thyroid disease.

Keywords: Antibodies; Child; Thyroid gland; Thyrotropin; Vitiligo

Vitiligo is seen in autoimmune thyroid conditions: chronic lymphocytic thyroiditis (Hashimoto's disease), the most common cause of hypothyroidism; Graves' disease, the most common etiology of hypothyroidism. Data on the frequency of children with vitiligo are inconsistent.^1-6 Hashimoto's Disease is characterized by painless diffuse nodular goiter and increased anti-thyroglobulin and thyroperoxidase enzyme (anti-TPO). Hypothyroidism is rare in children, and affects girls with a family history of thyroid condition more; there is polyuria, nycturia, exophtalmos, enlarged thyroid, fine tremor (warm and humid) of hands and tongue; tachycardia, divergent BP, weight loss and difficulty to concentrate; the diagnosis is confirmed by elevated free and total T3 and T4. Measurement of thyroid - stimulating hormone (TSH) which identifies unsuspected or oligosymptomatic disease is proposed as laboratory screening for thyroid dysfunction. An anti-TPO positive antibody is present in autoimmune thyroid dysfunctions.^7-8

Study design: case-control in which exposure factors calculated are altered serum levels of TSH and the presence of auto antibodies.

Fifty children (0-12 years) with vitiligo (test group), selected through a random draw among 120 individuals with the condition, and 40 (0-12 years) individuals without it, recruited during blood collecting for routine tests for other conditions, were evaluatedbetween 01/30/2003 and 01/30/2006 at IPPMG-UFRJ.

Exclusion Criteria (cases and controls): individuals on immunosuppressants, anticonvulsants, salicilates, iodides, sulfas, isoniazid, penicillin; diabetes mellitus, pernicious / hemolytic anemia, Down/Turner syndromes, Addison's disease, collagenoses, kidney, liver, heart conditions or malnutrition.

Vitiligo is defined clinically as ivory-white macules, well circumscribed and hiperpigmentada/hypopigmented with poliosis.

Examination for thyroid dysfunction includes gland palpation, heart rate, blood pressure and observation of sudoresis, polyuria, nycturia, fine tremor of hands and tongue. Venous blood samples collected in the morning (eight-hour fasting) were frozen at -70oC until all had been collected for simultaneous hormone and immunologic dosing.

Chemiluminescence Method– Diagnostic Products Corporation (DPC) – was used for serum dosing of TSH (N= 0.4 to 4 µU/mL) and anti-TPO (Negative: < 35 UI/mL; Positive: > 35 UI/mL). ⁷

A signed informed consent form was attained from guardians.

In the test group (9 µwhite / 8 non white and 18 µwhite / 15 non white), there were 24 cases of generalized vitiligo, 9 segmental, 7 focal, 5 mucous and 5 acrofacial; in the control group, 9 µwhite / 11 non white and 13 µwhite / 7 non white, 17 (34%) children in the test group and 8 (20%) controls had a family history of thyroid condition; the ratio was the same in both groups (p=0.064) (Table 1).

There was an increased serum level of TSH (6.56µU/ml) in one case in the test group (10 years, white, vulvar mucous form) and in one control: 8 years, non white, with psoriasis, positive family history of thyroid condition (4.27µU/ml). Anti-TPO was negative for both groups (Table 2).

There was no evidence of thyroid disease in any of the groups.

ublications available are case series that include adults, adolescents and children, and are vague regarding lab tests used, which make a correct assessment of the association vitiligo/thyroid condition in the pediatric age group difficult. ^{1, 2, 4, 9, 10}

Only three observational studies with children (= 12 years) with vitiligo have been published: 1 case of thyroid disease/625 (0.16%) 5; 1 case of hypothyroidism/73 (1.3%) 3; 2 cases with anti-thyroid antibodies /59 (3.4%) 3; 1 case with altered TSH/66 (1.6%). ³

The meaning of anti-TPO in the absence of clinical signs and the importance of screening individuals with vitiligo is speculative. The results of the present case control study did not show a higher risk for thyroid disease and anti-thyroid antibodies. With the present knowledge no changes regarding vitiligo are observed even if a gland dysfunction is detected and treated.

REFERENCES

• 1. Pagovich OE, Silverberg JI, Freilich E, Silverberg NB. Thyroid abnormalities in pediatric patients with vitiligo in New York city. Cutis. 2008;81:463-6.
• 2. Iacovelli P, Sinagra JLM, Vidolin AP, Marenda S, Capitanio B, Leone G. Relevance of thyroiditis and of other autoimmune diseases in children with vitiligo. Dermatology. 2005;210:26-30.
• 3. Silva CMR, Pereira LB, Gontijo B, Ribeiro GB. Vitiligo na infância: características clínicas e epidemiológicas. An Bras Dermatol. 2007;82:47-51.
• 4. Kurtev A. Thyroid function and autoimmunity in children and adolescents with vitiligo. J Eur Acad Dermatol Venereol. 2004;18:99-117.
• 5. Handa S, Dogra S. Epidemiology of childhood vitiligo: a study of 625 patients from North Índia. Pediatric Dermatol. 2003;20:207-10.
• 6. Kuhl IC, Weissbluth ML, Bakos L, Wollmann TM. Pesquisa de autoanticorpos e funçăo tireoidiana em pacientes portadores de vitiligo e alopecia areata. An Bras Dermatol. 1995;70:421-5.
• 7. Buescu A, Grego Filho J. Propedęutica nas doenças da tireoide. In: Carneiro AJV, Fraga EG, Pimentel ML, Vargas SSM, editores. Clínica médica. Doenças da tireóide. Săo Paulo: Atheneu; 2003. p.1-23.
• 8. Guimarăes MM. Doenças tireoidianas na infância. In: Carneiro AJV, Fraga EG, Pimentel ML, Vargas SSM editores. Clínica médica. Doenças da tireóide. Săo Paulo: Atheneu; 2003. p.119-44.
• 9. Kakourou T, Kanaka-Gantenbein C, Papadopoulou A. Increased prevalence of chronic autoimmune (Hashimoto's) thyroiditis in children and adolescents with vitiligo. J Am Acad Dermatol. 2005;53:220-3.
• 10. Schallreuter KE, Lemke R, Brandt O. Vitiligo and other diseases: coexistence or true association ? Study on 321 patients. Dermatology. 1994;188:269-75.

*

Trabalho realizado no Instituto de Puericultura e Pediatria Martagão Gesteira (IPPMG) e Hospital Universitário Clementino Fraga Filho da Universidade Federal do Rio de Janeiro (HUCFF/UFRJ) – Rio de Janeiro (RJ), Brasil.

Publication Dates

• Publication in this collection
  03 June 2009
• Date of issue
  Apr 2009

History

• Accepted
  01 Nov 2008
• Received
  21 June 2007