ONTOLOGY IN DIALOGUE

In its first section the volume contains contributions dealing with the debate between the German philosopher Markus Gabriel and some scholars in Palermo who discussed the fundaments of his ontology. In the next sections are gathered essays on critical ontology in the modern age, essays on intersubjectivity in social ontology and on ontology of arts and aesthetics

Levothyroxine Monotherapy Cannot Guarantee Euthyroidism in All Athyreotic Patients

CONTEXT: Levothyroxine monotherapy is the treatment of choice for hypothyroid patients because peripheral T4 to T3 conversion is believed to account for the overall tissue requirement for thyroid hormones. However, there are indirect evidences that this may not be the case in all patients. OBJECTIVE: To evaluate in a large series of athyreotic patients whether levothyroxine monotherapy can normalize serum thyroid hormones and thyroid-pituitary feedback. DESIGN: Retrospective study. SETTING: Academic hospital. PATIENTS: 1,811 athyreotic patients with normal TSH levels under levothyroxine monotherapy and 3,875 euthyroid controls. MEASUREMENTS: TSH, FT4 and FT3 concentrations by immunoassays. RESULTS: FT4 levels were significantly higher and FT3 levels were significantly lower (p<0.001 in both cases) in levothyroxine-treated athyreotic patients than in matched euthyroid controls. Among the levothyroxine-treated patients 15.2% had lower serum FT3 and 7.2% had higher serum FT4 compared to euthyroid controls. A wide range of FT3/FT4 ratios indicated a major heterogeneity in the peripheral T3 production capacity in different individuals. The correlation between thyroid hormones and serum TSH levels indicated an abnormal feedback mechanism in levothyroxine-treated patients. CONCLUSIONS: Athyreotic patients have a highly heterogeneous T3 production capacity from orally administered levothyroxine. More than 20% of these patients, despite normal TSH levels, do not maintain FT3 or FT4 values in the reference range, reflecting the inadequacy of peripheral deiodination to compensate for the absent T3 secretion. The long-term effects of chronic tissue exposure to abnormal T3/T4 ratio are unknown but a sensitive marker of target organ response to thyroid hormones (serum TSH) suggests that this condition causes an abnormal pituitary response. A more physiological treatment than levothyroxine monotherapy may be required in some hypothyroid patients

[Circulating immunocomplexes in patients with various morbid conditions].

The polyethylenglycol (PEG) precipitation technique has been employed for the measurement of immune complexes in the circulation of 100 normal subjects and in 14 patients suffering from a variety of diseases (systemic lupus erythematodes, nephrosic syndrome, cryoglobulinaemia, Buckley's syndrome). Values higher than 0.80 UA on the absorption scale were considered pathological, namely 2 standard deviations above the mean (0.32 UA) in the subjects examined; in the patients, values between a minimum of 0.98 UA and a maximum of 2.38 UA were observed. Longitudinal study of these cases also pointed to the disappearance of immune complexes during therapy. The results suggest that the PEG precipitation technique can play an important part as a screening test in situations in which circulating IC pathology is suspected; it is also a sensitive means of monitoring treatment