Aspectos ultra-sonográficos e prevalência da tireoidite pós-parto em gestantes sem disfunção tireóidea atendidas em hospital público de São Paulo

Abstract

RESUMOAvaliamos prospectivamente a função, as imagens ultra-sonográficas e a auto-imunidade tireóidea em grupo racial heterogêneo de 800 mulheres grávidas, primíparas ou multíparas (1 a 7 gestações prévias) atendidas em hospital universitário de São Paulo durante o pré-natal. Quarenta e seis pacientes foram excluídas do estudo por apresentarem diagnóstico confirmado de doença tireóidea anterior; das 754 restantes, 386 abandonaram o seguimento antes ou após o parto. Assim, a coorte avaliada no puerpério constituiu-se de 368 puérperas, examinadas aos 3, 6, 12 meses e no 2º ano pós-parto. Embora 29 pacientes tenham tido aumento transitório daqueles anticorpos antitireóideos, caracterizando reação de auto-imunidade, estes progressivamente declinaram ou tornaram-se negativos durante o puerpério. Entretanto, nenhuma destas evoluiu com disfunção tireóidea durante o acompanhamento. Quarenta e nove pacientes (13,3%) desenvolveram progressivamente alterações funcionais da tireóide (principalmente hipotireoidismo), provavelmente devido à TPP. Além disso, a continuação do seguimento mostrou que em 18 a 24 meses, 42 mostraram níveis séricos de anti-TPO mais elevados, em comparação aos valores do primeiro ano. Os fatores de risco para o desenvolvimento da TPP, presentes durante a gravidez, foram: (1) níveis relativamente baixos de anti-TPO, entre 60 e 100U/mL [risco relativo ou odds ratio de 3,1] e (2) alterações estruturais ultrasonográficas da tireóide no primeiro trimestre [odds ratio de 6,4]. Concluí-mos que a prevalência de TPP em hospital público de São Paulo foi de 13,3%, considerando as 368 pacientes seguidas. Em 29 puérperas foi diagnosticada forma transitória de reação tireóidea auto-imune, caracterizada por elevação dos níveis séricos de anti-TPO, que posteriormente regrediram. ABSTRACTWe evaluated thyroid function, ultrasound images and presence of autoantibodies in a mixed racial group of 800 unselected primiparous or multiparous (1-7 previous pregnancies) pregnant women attended in a public hospital in the city of São Paulo. Forty-six patients were excluded from the study because of a confirmed diagnosis of a thyroid condition. Thus, a total of 754 women were available for further studies in the postpartum period. A relatively large number of those patients (n= 386) were lost or unavailable to follow-up either before or after delivery. A cohort of 386 puerperal healthy women was followed-up regularly at 3, 6, 12 and 24 months during the postpartum period, with regular thyroid function tests, random urine iodine measurements, assays for serum autoantibodies against thyroid antigens and imaging by ultrasound. Twenty-nine patients had a transient rise of anti-TPO-Ab characterizing an autoimmune reaction. These antibodies titres progressively declined or became negative. Moreover none of these patients have evidence for altered thyroid function during the 18-24 months of follow-up. Forty-nine patients (13.3%) changed their thyroid status, mainly to hypothyroidism, indicating perspectivas

Variation of iodine status during pregnancy and its associations with thyroid function in women from Rio de Janeiro, Brazil

“…However, the present study and the recent report by Saraiva et al (16) corroborate that the results obtained in São Paulo should not be extrapolated to the entire population of pregnant women in Brazil, a country with continental proportions and different profiles of iodine consumption, even in a single region. Compared with previous Brazilian studies, ours was the only one designed to evaluate the changes in iodine nutrition during the course of gestation because we measured UIC in the first and third trimesters in the same participant, while all other studies were done in a crosssectional manner (16)(17)(18)33,34) . In addition, considering the great variability of UIC, we sought to minimize this effect by analysing multiple urine samples from each pregnant woman.…”

Nutritional Status of Iodine in a Group of Pregnant Women from the State of Minas Gerais Correlated with Neonatal Thyroid Function

“…[3][4][5] Brazilian data on iodine sufficiency in pregnant women are controversial. In 2001, Barca et al 15 showed iodine sufficiency in 20 pregnant women attended in a public hospital of São Paulo, with iodine excretion represented by the median of urinary concentration of 167.8 mcg/l. In 2008, Soares et al 22 evaluated 147 pregnant women in Porto Alegre and obtained urinary iodine levels between 22 and 534 mcg/l, with 19.6% of the pregnant women showing urinary iodine concentration lower than 150 mcg/l, and median of 224 mcg/l, that is, adequate levels of urinary iodine concentration.…”

“… 14 The urinary iodine concentration measurement (in mcg/L) of occasional aliquots is considered as the real laboratory biochemical parameter for iodine use by the community. 15 Urinary iodine concentration was determined using inductively coupled plasma mass spectrometry. The manufacturer's reference interval was from 70 to 530 μg/g of creatinine.…”

Iodine nutritional status in Brazil: a meta-analysis of all studies performed in the country pinpoints to an insufficient evaluation and heterogeneity

“…Only few studies have analyzed pregnant women (25,30,43). Interesting, Ferreira evaluated 191 pregnant women in Ribeirao Preto, Sao Paulo, and found a very high IDD prevalence (57%) and an average UI of 144.4 μg/L (43).…”