The ‘euthyroid sick syndrome’: incidence, risk factors and prognostic value soon after allogeneic bone marrow transplantation

Abstract

We studied the incidence of thyroid function abnormalities observed soon after allogeneic bone marrow transplantations (BMT) and their predictive value on the overall prognosis. Free serum thyroxine, free serum triiodothyronine, total serum reverse triiodothyronine and serum thyrotropin levels were systematically measured in 78 patients before and 3 months after BMT. 41 (52%) had normal hormone levels and 37 (48%) had abnormal ones, among whom four (5%) had peripheral compensated hypothyroidism and 33 (43%) were described as having 'euthyroid sick syndrome' (low thyroxine state, or low T3 syndrome). Two factors strongly influenced the appearance of thyroid abnormalities: steroid dose at the time of thyroid function testing, and age (< or = 16 years/ > 16 years). Among the younger patients, 21 had no thyroid abnormalities, while five did. Among the older patients, 20 had no thyroid abnormalities, while 32 did (P < 0.001). The occurrence of thyroid abnormalities seemed to influence survival strongly, since the 30-month projected survival time was 83% for patients without abnormalities whereas it was 49% for patients with an abnormal profile (P < 0.001). In conclusion, evidence obtained among our population reveals that euthyroid sick syndrome indicates a poor prognosis and that it is very important to monitor thyroid hormone levels (particularly free hormones) soon after allogeneic BMT and regularly thereafter.

Relationship between circulating cytokine levels and thyroid function following bone marrow transplantation

“…The patients with low T 4 level at post-BMT 3 weeks had lower 1-year survival rate than those with normal T 4 level, which is in agreement with previous data. [7][8][9][10] No significant differences in thyroid hormone parameters were found according to the presence or severity of GVHD, which is similar to the finding of Vexiau et al 11 Cytokines were not significantly different between those patients who have subsequently died before 1 year post-BMT and those surviving.…”

“…The incidence of ESS after BMT is reported to be 43% at 3 months post-BMT, 11 but no study has assessed the serial changes of thyroid hormone parameters in the earlier post-BMT period, during which ESS development is expected to be more prominent and rapid. In our study, 91.3% patients had ESS, and low T 3 syndrome occurred in 58.8% patients and low T 3 , T 4 syndrome in 32.5% patients over the 6 months after BMT.…”

“…In a study of 78 patients undergoing allogeneic BMT, the 30-month projected survival time was 83% for patients without thyroid abnormalities but only 49% for patients with abnormal thyroid profiles. 11 In this study, we analyzed the relation of thyroid dysfunction and mortality. Significant differences were found in serum T 4 level between those patients who have subsequently died before 1 year post-BMT and those surviving.…”

“…[7][8][9][10] In patients undergoing bone marrow transplantation (BMT), the development of ESS indicates a poor prognosis. 11,12 Recently, attention has been focused on the role of cytokines in the pathogenesis of ESS. An increase in serum interleukin-6 (IL-6) and of tumor necrosis factor-a (TNF-a) concentrations was reported in ESS patients, especially those with low T 3 concentration.…”

Low triiodothyronine (T3) state: a predictor of outcome in respiratory failure? Results of a clinical pilot study

“…The low T3 state has been described in starvation (4), sepsis (5), surgery (6), myocardial infarction and heart failure (7,8), cardiopulmonary bypass (9), bone marrow transplantation (10) and any other severe illness (11).…”