Endocrine Abstracts

Introduction: The treatment of central hypothyroidism with a combination of levothyroxine (T4) and liothyronine (T3) is not recommended for most patients since it does not show an advantage over T4L monotherapy. However, in certain patients who remain symptomatic under replacement therapy with T4L and thyroid stimulating hormone (TSH) within the reference values, combined treatment with T4 and T3 can be tested.

Clinical case: Male, 39 years old, medical history of craniopharyngioma, submitted to surgical intervention with subsequent panhypopituitarism. Medicated with 125 mg levothyroxine, 10 mg hydrocortisone, 0.12 mg desmopressin and monthly dose of testosterone. The patient was admitted for septic shock due to Klebsiella pneumoniae cellulitis, aggravated by pyelonephritis due to Morganella morganni, with acute kidney injury and metabolic acidemia, requiring aminergic support and non-invasive ventilation, being submitted to several cycles of antibiotic therapy. Despite the reversal of the infectious condition and improvement in renal function, the patient remained in comatose state, hypotensive (89–65 mmHg), bradycardic (51bpm) and hypothermic (33.4ºC). Blood test showed hyponatremia (130 mEq), normoglycemia (78 mg/dl), free T4 within the reference values (1.10 ng/dl), but with non-dosable free T3, despite 40 days of 150 mg levothyroxine therapy. A deficient conversion of T4 to T3 was assumed and treatment with 75 mg of T3 was started, showing a remarkable improvement in consciousness after 1 day of therapy and normalization of temperature (37.2ºC), blood pressure (112–60 mmHg) and heart rate (60bpm) after 3 days, having gradually discontinued liothyronine. At the date of suspension with 1.52 ng/dl of free T4 and 2,72 pg/ml of free T3.

Discussion: The patient presented hypothyroidism decompensation secondary to sepsis. Initially, the patient’ recovery was expected after normalization of the clinical status and normalization of T4 levels. However, the patient maintained a weakened clinical condition, disagreeing with the analytical data, so a combination of thyroid hormone therapy was implemented. This combination therapy should be performed under close monitoring, given the potency of T3 (3 times more potent than T4). The present case highlights that in patients with severe hypothyroidism, including coma, with poor response to T4 replacement, the combination with T3 may be useful, although not recommended.