Læknablaðið : fylgirit - 01.06.1982, Blaðsíða 41

28
SUPPRESSION OF THE NIGHT INCREASE IN SERUM TSH DURING
DEVELOPMENT OF KETOSIS IN DIABETIC PATIENTS
X XX m X
O. Schmitz . K.G.M.M. Alberti , A.B. Hreidarsson ,
X
P. Laurberg , J. Weeke , and H. Orskov .
XFirst and Second University Clinic of Internal Medicine,
Kommunehospitalet Aarhus. Institute of Clinical Experimental
Research, University of Aarhus, DK-8000 Aarhus Denmark and
XX
Department of Clinical Biochemistry, Royal Victoria
Infirmary, Newcastle-upon-Tyne, U.K.
The alterations in metabolic parameters, cirulating iodothyro-
nines and serum TSH were studied during a 81 h period of in-
sulin withdrawal in 6 young patients with juvenile type dia-
betes mellitus. Concomitant with the dearangement of metabolic
state a significant fall in serum T^ (in average 27%), serum
free T^ (28%), and T (12%) was observed. Serum free T re-
mained unchanged. Before and after the period of ketosis the
normal diurnal pattern of high serum TSH at night and low
levels during the daytime period was observed. During the
period of ketosis+the night level of serum TSH was significant-
ly depressed (46 - 9% lower at 23.00 h, p<o.ol) while no
significant alterations occured in daytime TSH. Both the vari-
ations in T^, reverse T (rT^) and night TSH were correlated
to the increase in blood-3-hydroxybutyrate. The depression of
the night surge in serum TSH may be of importance for the fall
in circulating levels of active iodothyronines during the
initial phase of illness, together with the wll known inhibi-
tion of T^ deiodination to T^ in peripheral tissues occurring
in acute íllness.