Abstract | Hashimotov tireoiditis (HT) je najčešća autoimuna endokrinološka bolest, obuhvaća do 10%
populacije te je danas vodeći uzrok hipotireoze. Karakterizira ga povišen titar protutijela na
tireoidnu peroksidazu (TPOAt) i tireoglobulin (TgAt). Obzirom na rastuće dokaze o utjecaju
tireoidnih protutijela na kliničku manifestaciju bolesti, proveli smo opširnu fenotipsku
karakterizaciju bolesnika s HT-om, s posebnim naglaskom na autoimunost, kako bismo bolje
razumjeli etiologiju i simptomatologiju ove bolesti.
Ispitanici su regrutirani u sklopu Ambulante za bolesti štitnjače Kliničkog zavoda za nuklearnu
medicinu u Kliničkom bolničkom centru Split, u razdoblju od 2013. do 2017. g. Ukupno smo
uključili 491 ispitanika kojima je dijagnoza HT-a postavljena na temelju kliničkog pregleda uz
ultrazvučni pregled štitnjače s ehografskim karakteristikama difuzne bolesti te biokemijsko
mjerenje razine hormona i protutijela.
Prikupili smo informacije o kliničkim karakteristikama kojima se definira HT (TSH, T3, T4, FT4,
TgAt, TPOAt, volumen štitnjače) i fenotipskim karakteristikama ispitanika (dob ispitanika,
BSA, broj simptoma hipotireoze, sistolički i dijastolički arterijski tlak) s ciljem ispitivanja
korelacija među njima. Posebno smo se usredotočili na analiziranje skupine koja uključuje
290 ispitanika koji nisu na terapiji LT4, s ciljem detaljnijeg ispitivanja utjecaja autoimunosti
na kliničku manifestaciju bolesti. Također, dodatno smo analizirali i razlike između dviju
podskupina ispitanika koje smo podijelili u odnosu na uzimanje terapije levotiroksinom (LT4).
Najznačajniji rezultat naše studije je po prvi put ustanovljena pozitivna korelacija TgAt s
brojem simptoma u skupini ispitanika koji nisu na terapiji LT4 (r = 0,25, P = 0,0001), koja
ostaje značajna i nakon prilagodbe za razinu TPOAt, T3, TSH i volumena štitnjače (β = 0,66, SE
= 0,3, P = 0,0299). Pronašli smo statistički značajnu povezanost razine TgAt sa sljedećim
simptomima: lomljivost kose (P = 0,0043), edem lica (P = 0,0061), otečenost očnih kapaka (P
= 0,0293), promuklost glasa (P = 0,0349). Prema rezultatima naše studije, povišena razina
TgAt povezana je s povećanim brojem simptoma kod bolesnika s HT-om, što ukazuje na
ulogu tireoidne autoimunosti u kliničkoj manifestaciji bolesti. U skladu s tim, preporučujemo
ispitivanje razine TgAt kod bolesnika s HT-om koji imaju izraženije kliničke tegobe te
smatramo da su nužna daljnja istraživanja kako bismo razlučili koji simptomi su posljedica
smanjene funkcije štitnjače; a koji od simptoma su autoimune etiologije. |
Abstract (english) | Hashimoto's thyroiditis (HT) is the most common form of autoimmune endocrine disorders,
affecting up to 10% of population and it is leading cause of hypothyroidism today. HT is
characterized by positivity to autoantibodies to thyroglobulin (TgAb) and thyroid peroxidase
(TPOAb). Intrigued by the rising evidence of the role of thyroid antibodies on disease
manifestation, we performed a comprehensive phenotypic characterization of patients with
HT, with specific focus on thyroid autoimmunity, to get better understanding of disease
manifestation.
Patients were recruited at the Outpatient clinic for thyroid disorders in Nuclear Medicine
Department at the University Hospital of Split in the period from 2013 to 2017. Our cohort
included 491 subjects whom diagnosis of HT has been established with clinical examination
including thyroid ultrasound with typical echographic pattern of diffuse thyroid disease,
complemented with biochemical measurements of hormones and thyroid antibodies.
We collected information on HT related clinical parameters (TSH, T3, T4, FT4, TgAb, TPOAb,
thyroid volume) and patients’s phenotypes (age, BSA, number of hypothyroidism symptoms,
blood pressure) with aim to test for correlations between them. We especially investigated
data from 290 patients with HT without levothyroxine (LT4) therapy with the aim to evaluate
possible association of autoimmunity on clinical manifestation. Moreover, we have analyzed
differences between two subgroups of HT patients depending on levothyroxine (LT4)
therapy-intake.
Our key and novel finding is the existence of significant positive correlation between TgAb
levels and the number of symptoms (r = 0.25, P = 0.0001) in HT patients without LT4 therapy,
that remained significant after adjustment for TPOAb, T3, TSH levels and thyroid volume (β =
0.66, SE = 0.3, P = 0.0299). Increased TgAb levels are significantly associated with fragile hair
(P = 0.0043), face edema (P = 0.0061), edema of the eyes (P = 0.0293) and harsh voice (P =
0.0349). According to the results of our study elevated TgAb levels are associated with
symptom burden in HT patients, suggesting a role of thyroid autoimmunity in clinical
manifestation of HT. Based on these results; we recommend screening for TgAb antibodies
in HT patients with symptom burden. We also suggest that further work on understandings
of symptoms appearance due to their autoimmune or hypothyroid causation is needed. |