Cerebrospinal fluid proteins in subclinical and overt hypothyroidism.
METHODS
We analysed cerebrospinal fluid (CSF) albumin and immunoglobulin G (IgG) concentrations and psychometric performance in subclinical (n = 6) and overt hypothyroidism (n = 9) before and after 6 months with L-thyroxine.


RESULTS
In overt hypothyroidism, CSF albumin and IgG concentrations were increased before therapy [mean(SD): 328(156) mg/l and 69(27) mg/l], but within the reference interval [198(48) mg/l and 39(11) mg/l], P < 0.05, after therapy. In contrast, in subclinical hypothyroidism CSF protein concentrations were within the reference intervals before and after therapy. Psychometric testing indicated an improvement in performance in both groups.


CONCLUSIONS
The increase in CSF proteins in overt hypothyroidism does not appear to be related to thyroid autoimmune disease per se, since we found no increase in CSF proteins in individuals with subclinical hypothyroidism and presence of thyroid antibodies. The increase might rather be caused by a blood-brain barrier dysfunction related to low thyroid hormone concentrations.
Nyström
E
E
Department of Endocrinology (The Thyroid Unit), Sahlgren's University Hospital, University of Göteborg, Sweden.
Hamberger
A
A
Lindstedt
G
G
Lundquist
C
C
Wikkelsö
C
C
D000328:Adult; D000418:Albumins / Q000032:analysis; D001812:Blood-Brain Barrier; D002556:Cerebrospinal Fluid Proteins / Q000737:chemistry*; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000134:cerebrospinal fluid*; D007074:Immunoglobulin G / Q000032:analysis; D008875:Middle Aged; D011594:Psychometrics; D013972:Thyrotropin / Q000172:deficiency
D000418:Albumins; D002556:Cerebrospinal Fluid Proteins; D007074:Immunoglobulin G; D013972:Thyrotropin