Endocrine Abstracts

Methods: A prospective study in 35 patients hospitalized for AKI for two consecutive years was carried out. TFT (serum thyrotropin, TSH; free thyroxine, FT₄; and total triiodothyronine, T₃ concentrations) were measured in each patient on three occasions: at admission, at hospital discharge and at their first outpatient visit.

Results: Total prevalence of alterations in TFT was 82.9% (n=29). Of those, euthyroid sick syndrome (ESS) with low T₃ only was the most common (n=13, 37.1%) derangement. In the whole group of patients TSH (0.93 (0.35–2.27) μU/ml) and FT₄ (1.2±0.3 ng/dl) were normal, whereas T₃ was low (0.7±0.1 ng/ml). TSH, FT₄ and T₃ were similar in different types of AKI. In the simple regression analysis we only found a negative correlation between TSH and serum urea concentrations (ρ=−0.382; P=0.024). At hospital discharge (median hospital stay 6 days (2–10)), TFT showed significant changes only in T₃ concentrations (0.8±0.3 ng/ml, P=0.013). At this point, the percentage of patients with normal TFT increased from 17.1% at baseline to 40% at discharge and then to 66.7% at their first outpatient visit. We found no association between the presence and type of alterations in TFT and clinical (sex, age, personal history of diabetes and/or hypertension, number and type of drugs used, signs and symptoms, and degree, type and etiology) and prognostic (hospital stay, recovery of renal function, need of renal replacement therapy, residual chronic renal failure and mortality) factors associated to AKI.

Conclusion: Over 80% of AKI patients exhibit alterations in TFT. The commonest derangement is ESS (~70%), mainly low T₃ syndrome, which is present in about one third of the patients with altered TFT. ESS recovers spontaneously as renal function improves. The presence of TFT alterations seems not to be associated with clinical and prognostic implications in AKI patients.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.