A Patient with Postpartum Hypopituitarism (Sheehan's Syndrome) Developed Postpartum Autoimmune Thyroiditis (Transient Thyrotoxicosis and Hypothyroidism): A Case Report and Review of the Literature

Table 1

Results of thyroid and adrenal function tests and TPOAb and TGAb at 1 month before delivery (−1 m) (1 month ante partum) and 1–10 months after delivery (1–10 m) (1–10 months post partum).

Months (m)*	−1 m	1 m	2 m	4 m	6 m	7 m	8 m	9 m	10 m
Free T3 pmol/L	4.9	26.2	28.5	2.5	1.5	1.2	2.3	2.5	3.9
Free T4 pmol/L	15.4	70.8	75.9	4.3	1.4	0.9	8.7	10.9	15.4
TSH mIU/L	2.2	<0.005	<0.005	6.6	16.8	24.8	20.8	17.4	2.8
ACTH pmol/L	11.5	<0.4	<0.4**		<0.4**
Cortisol nmol/L	690	<5.5	<5.5**		<5.5**
TPOAb kIU/L	3.4		42.2		34.1				26.8
TGAb kIU/L	52.0		138.4		126.7				102.3
TRAb IU/L	0.3		0.4		0.5				0.4

Months (m)*: −1 m: 1 month before delivery (1 month ante partum) and 1–10 m: 1–10 months after delivery (1–10 months post partum). **Oral hydrocortisone (HC) had been discontinued for 1 week before the study. Free T3: free triiodothyronine, free T4: free thyroxine, TPOAb: antithyroid peroxidase antibody, TGAb: antithyroglobulin antibody, and TRAb: TSH receptor antibody. Normal reference ranges: free T3 3.5–6.6 nmol/L, free T4 11.6–21.9 pmol/L, TSH 0.4–4.20 mIU/L, ACTH 1.70–12.27 pmol/L, cortisol 110–505 nmol/L, TPOAb < 0.3 kIU/L, TGAb < 0.3 kIU/L, and TRAb (TRAb (human)) < 1.0 IU/L.
A patient with postpartum hypopituitarism (SS) developed postpartum autoimmune thyroiditis (PPAT). At 1 month post partum, she had thyrotoxicosis. She was negative for TRAb. She was positive for TPOAb and TGAb. TPOAb- and TGAb-titers increased after delivery. Serum thyroglobulin was 72 μg/L (normal < 32 μg/L). She had painless thyroiditis (autoimmune destructive thyroiditis). She had thyrotoxicosis due to destructive thyroiditis. ACTH was less than 0.4 pmol/L and cortisol was less than 5.5 nmol/L. She had ACTH deficiency and secondary hypoadrenalism; HC was started. At 4 months, she had hypothyroidism with TSH 6.6 mIU/L. At 6 months, TSH was 16.8 mIU/L. At 7 months, thyroxine (T4) was started. She had thyrotoxicosis at 1-2 months post partum and then hypothyroidism (PPAT). She had hypopituitarism (SS). She is now taking T4 and HC.