[Autoimmune thyroid diseases associated with glomerular nephropathy. 3 cases].

Area of Science:

• Nephrology
• Immunology
• Endocrinology

Background:

• Thyroid autoimmune diseases, such as Hashimoto's thyroiditis and Graves' disease, are common endocrine disorders.
• Glomerulonephritis encompasses a group of kidney diseases affecting the glomeruli.
• The association between thyroiditis and glomerulonephritis is not fully understood.

Observation:

• Three patients with different thyroiditis diagnoses presented with distinct forms of glomerulonephritis.
• Patient 1 (Hashimoto's thyroiditis) developed membranous glomerulonephritis with specific immune deposits.
• Patient 2 (Graves' disease) developed rapidly progressive glomerulonephritis post-radioiodine therapy.
• Patient 3 (Hashimoto's thyroiditis) presented with crescentic glomerulonephritis.

Findings:

• All patients exhibited circulating antithyroglobulin antibodies, with high titers in two.
• Immune complex analysis was negative in all patients at the time of renal biopsy.
• The study identified associations between thyroiditis and both membranous and crescentic glomerulonephritis.
• Thyroglobulin was detected in subepithelial deposits in one patient.

Implications:

• Glomerular lesions beyond the classical membranous type can be associated with thyroiditis.
• The subclinical nature of Hashimoto's thyroiditis necessitates routine screening for antithyroglobulin antibodies.
• Systematic antibody testing in women with idiopathic glomerulonephritis may reveal underlying thyroid disease.
• This highlights the importance of considering autoimmune thyroid disease in the differential diagnosis of glomerulonephritis.