Plasma glycosaminoglycans in endocrine ophthalmopathy

Abstract

With evidence on the important role of glycosaminoglycans (GAG) in the pathogenesis of endocrine ophthalmopathy (EO) having accumulated, the present study focused on the biochemical assessment of plasma GAG content in 37 EO patients as compared to 20 controls. Glycosaminoglycans were isolated from plasma samples by protein elimination, dialysis, and precipitation with ethanol and cetylpyridinium chloride. Patients (9.71, 5.09, 15.09 mg/100 ml; median, 25th, 75th percentile) exhibited significantly (p = 0.0021) higher plasma GAG levels than controls (4.6, 3.38, 6.8 mg/100 ml). Plasma GAG content was unrelated to age, sex, or antithyroid treatment. However, an even higher level of significance (p = 0.0001) was reached when discriminating between untreated patients with EO of recent onset (14.16, 10.35, 15.51 mg/100 ml) and controls. By contrast, steroid therapy of EO led to values (3.82, 1.85, 6.52 mg/100 ml) indistinguishable from those of the controls. Further statistical analysis of the results, based on a specificity of 95% for the control group, revealed a sensitivity of 91% for patients with untreated EO of recent onset, and a specificity of 100% for patients receiving steroid therapy. In comparison, plasma GAG content was determined in 8 untreated and in 6 treated EO patients by a second method already published. All untreated patients exhibited high GAG levels (median 2.23 mg/100 ml) whereas in treated EO patients normal plasma GAG values (0.17-0.34 mg/100 ml) were found. Follow-up determination of plasma GAG content in 7 patients undergoing steroid treatment unveiled a marked decrease of initially elevated values. These findings correlated well with clinical improvement of thyroid eye disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical activity score as a guide in the management of patients with Graves' ophthalmopathy

“…Kahaly has extensively studied the concentrations of glycosaminoglycans (GAGs) in the urine and plasma of patients with active and inactive, treated and not (yet) treated Graves' ophthalmopathy (Kahaly et al, 1990(Kahaly et al, , 1994Schuler et al, 1993). He found a significant Clinical activity score in Graves' ophthalmopathy 13 ᭧ 1997 Blackwell Science Ltd, Clinical Endocrinology, 47, 9-14 increase in GAGs in both the urine and plasma of patients with Graves' ophthalmopathy as compared with control groups.…”

Thyroid-associated Orbitopathy: Quantitative Evaluation of the Orbital Fat Volume and Edema Using IDEAL-FSE

“…The water fraction in orbital fat was greater in TAO patients than in the controls. Previous histological studies revealed lymphocytic infiltration and edema due to the accumulation of hydrophilic, interstitial glycosaminoglycans in the orbital fat and extraocular muscles of TAO patients [17,18]. Water retention was closely related to high osmolarity due to the accumulation of mucopolysaccharides in the orbit [19] and swollen orbital tissues impede venous outflow from the orbit.…”

Management of Graves' Ophthalmopathy: Reality and Perspectives

“…Kahaly and co-workers (85)(86)(87) reported, in a series of studies, that patients with active GO have increased plasma concentration and urinary excretion of GAG that tend to decrease after immunosuppressive management of the disease. The value of urine or plasma GAG determination in the assessment of GO activity, however, remains to be precisely defined.…”