Thyroid vascularity is increased in patients with active acromegaly.
OBJECTIVE
To determine whether acromegalic patients have increased thyroidal vascularity and blood flow on colour flow Doppler sonography (CFDS).


METHODS
Prospective study of consecutive patients.


METHODS
Twenty-four acromegalic patients (11 men, 13 women, age 49 +/- 9 years); 38 patients with nontoxic goitre (NTG; 12 men, 26 women, age 50 +/- 7 years); 36 normal subjects (controls; 16 men, 20 women, age 46 +/- 9 years). Among acromegalic patients, 10 had active, untreated disease (Acro-U), seven were in remission after surgery (Acro-R), seven had active disease under treatment with somatostatin analogues (SMSa) (Acro-SA) (Sandostatin LAR, 20 mg, every 28 days).


METHODS
CFDS pattern and intrathyroidal peak systolic velocity (PSV) were determined by a colour Doppler system with a 7.5-MHz linear transducer. PSV measurements were made at the level of the intrathyroidal arteries (normal values 3.8 +/- 1.0 cm/s). Thyroid volume was calculated by the ellipsoidal model. Assays included measurements of serum GH, IGF-I, free T4, free T3, TSH, antithyroglobulin (anti-Tg) and antithyroperoxidase (anti-TPO) antibodies, TSH-receptor antibodies (TRAb).


RESULTS
Serum GH (+/- SD) and IGF-I (+/- SD) levels were: Acro-U: GH 26 +/- 31 microg/l, IGF-I 783 +/- 299 microg/l; Acro-SA: GH 15 +/- 25 microg/l, IGF-I 366 +/- 212 microg/l; Acro-R: GH 1.3 +/- 1.0 microg/l, IGF-I 241 +/- 99 microg/l. To convert values for serum GH to mU/l multiply by 2.6; to convert values for serum IGF-I to nmol/l multiply by 0.13075. All controls had CFDS pattern 0 (absent vascularity or minimal spots); among NTG patients, 36 had pattern 0 and two had pattern I (parenchymal blood flow with patchy uneven distribution). Five patients with acromegaly had pattern 0, 12 had pattern I and seven pattern II (mild increase of colour flow Doppler signal with patchy distribution). Among the five acromegalic patients with pattern 0, three were Acro-R and two were Acro-SA. Among patients with pattern I, six were Acro-U, two were Acro-SA and four were Acro-R. Among patients with pattern II, four were Acro-U and three Acro-SA; two patients of the latter group had elevated serum IGF-I under SMSa treatment. Intrathyroidal PSV was 3.8 +/- 1.0 cm/s in controls, 4.0 +/- 1.1 cm/s in NTG, 7.4 +/- 0.8 cm/s in Acro-U, 4.9 +/- 1.3 cm/s in Acro-SA treatment and 4.5 +/- 1.0 in Acro-R. (Acro-U vs. Acro-SA, P = 0.0003; vs. Acro-R, Controls, or NTG, P < 0.0001). PSV values in Acro-SA were higher than those observed in NTG or controls (P = 0.05, P = 0.01, respectively); PSV values in Acro-R did not differ from those in NTG or controls. Intrathyroidal PSV values were correlated with serum IGF-I (r = 0.73, P < 0.0001) and, although less strongly, GH levels (r = 0.54, P = 0.01). Goitre was present in 19 of 24 patients; diffuse in three and nodular in 16. Thyroid function was normal in all subgroups of acromegalic patients. Anti-Tg, anti-TPO antibodies and TRAb were negative in all subjects.


CONCLUSIONS
Patients with active acromegaly have increased intrathyroidal blood flow (colour flow Doppler sonography pattern II, increased peak systolic velocity values); this was not observed in the large majority of patients under treatment with somatostatin analogues and in any patient in remission. Accordingly, colour flow Doppler sonography and peak systolic velocity measurements may be considered an additional useful peripheral parameter for rapid assessment of the activity of acromegaly.
Bogazzi
Fausto
F
Department of Endocrinology and Metabolism, University of Pisa, Italy. f.bogazzi@endoc.med.unipi.it
Manetti
Luca
L
Bartalena
Luigi
L
Gasperi
Maurizio
M
Grasso
Lucia
L
Cecconi
Elisabetta
E
Rago
Teresa
T
Pinchera
Aldo
A
Martino
Enio
E
D000172:Acromegaly / Q000097:blood / Q000000981:diagnostic imaging / Q000503:physiopathology*; D000208:Acute Disease; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012039:Regional Blood Flow; D012044:Regression Analysis; D018709:Statistics, Nonparametric; D013599:Systole; D013961:Thyroid Gland / Q000098:blood supply* / Q000000981:diagnostic imaging; D013963:Thyroid Hormones / Q000097:blood; D018615:Ultrasonography, Doppler, Color
D013963:Thyroid Hormones; D007334:Insulin-Like Growth Factor I