Prolonged APTT and autoimmune overt hypothyroidism identified postpartum: a case report

Area of Science:

• Endocrinology
• Hematology
• Reproductive Medicine

Background:

• Thyroid disorders are linked to coagulation system abnormalities, with hypothyroidism potentially causing a hypocoagulant state.
• Thyroid function assessment is not routinely part of coagulation disorder evaluation.
• Pregnancy complications like severe preeclampsia and intrauterine growth restriction can necessitate thorough postpartum biochemical assessments.

Observation:

• A 32-year-old woman with no prior thyroid history presented with postpartum coagulation abnormalities, including prolonged activated partial thromboplastin time (APTT), low factor VIII, and reduced von Willebrand factor (vWF) and thrombin generation.
• Routine biochemical assessment 6 months postpartum revealed these coagulation issues, prompting further investigation.
• Thyroid function tests identified overt autoimmune hypothyroidism, characterized by high thyroid-stimulating hormone (TSH) and antibody levels, and low peripheral thyroid hormones.

Findings:

• Prolonged APTT in this patient served as a crucial diagnostic indicator for underlying hypothyroidism.
• The case demonstrates a direct correlation between overt autoimmune hypothyroidism and significant alterations in multiple coagulation factors and thrombin generation.
• Biochemical evidence of a hypocoagulant state was observed in conjunction with severe hypothyroidism.

Implications:

• Measurement of TSH should be considered in the diagnostic workup of unexplained prolonged APTT or other coagulation anomalies.
• This case underscores the clinical significance of assessing thyroid function in postpartum patients with coagulation disturbances, especially after complicated pregnancies.
• Early identification of hypothyroidism through TSH measurement can be vital for managing associated hemostatic abnormalities.