Myxoedema coma: response of thyroid hormones with oral and intravenous high-dose L-thyroxine treatment.
Myxoedema coma is a medical emergency with high mortality. In this study, clinical response and plasma variations of thyroid hormones were analysed in 7 patients, 6 presenting with myxoedema coma and one with myxoedema ileus. These patients were treated with intravenous or oral l-thyroxine (l-T4). 1000 mu l-T4 iv were administered in two patients. Within 3 h, plasma T4 and triiodothyronine (T3) reached a peak upper normal range, then diminished slowly during 5-9 days. The 5 remaining patients were treated with 500 micrograms l-T4 po on the first day, then 100 micrograms l-T4 daily by mouth. Plasma T4 and T3 increased slowly, remaining in hypothyroid range but clinical response (assessed on mental status, pulse rate and body temperature) occurred within 24-72 h. Cortisone therapy was used in 3 patients. Two patients died of myocardial infarction, or septicemia, one while receiving cortisone therapy and i.v. l-T4, another one treated only by oral l-T4. This study suggests: 1) oral absorption of l-T4 is variable, but clinical response occurs quickly even in myxoedema ileus; 2) the intravenous route involves high peaks of plasma T4 and T3; 3) peripheral conversion of T4 to T3 allows gradually T3 delivery to organ systems, even if only l-T4 is used and 4) initial and daily dosage determinations need further studies.
Arlot
S
S
Service de Médecine Interne-Endocrinologie, Centre Hospitalier Régional, France.
Debussche
X
X
Lalau
J D
JD
Mesmacque
A
A
Tolani
M
M
Quichaud
J
J
Fournier
A
A
D000284:Administration, Oral; D000368:Aged; D003128:Coma / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality; D003348:Cortisone / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007262:Infusions, Intravenous; D008875:Middle Aged; D009230:Myxedema / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011379:Prognosis; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D014284:Triiodothyronine / Q000097:blood
D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine; D003348:Cortisone; D006854:Hydrocortisone