Thyroid lipomatosis in a 36-year-old patient with rheumatoid arthritis and a kidney transplant

Abstract

SummaryThyroid lipomatosis is a rare disease, as a total of 20 cases have been described in the literature. It is characterized by diffuse infiltration of the stroma by mature adipose tissue and by progressive growth that produces different degrees of compressive symptoms. Our aim is to present the case of a 36-year-old woman who consulted because of dyspnea caused by a multinodular goiter. She underwent surgery with the presumptive diagnosis of a malignant neoplasia, but the pathological examination of the surgical specimen established the diagnosis of thyroid lipomatosis.Learning points Thyroid lipomatosis is a rare, benign disease characterized by diffuse infiltration of the stroma by mature adipose tissue.The pathophysiology of diffuse proliferation of adipose tissue in the thyroid gland is unclear.Thyroid lipomatosis is clinically manifested by a progressive enlargement of the thyroid that can involve the airway and/or upper gastrointestinal tract, producing dyspnea, dysphagia, and changes in the voice.Given the rapid growth of the lesion, the two main differential diagnoses are anaplastic carcinoma and thyroid lymphoma.Imaging studies may suggest a differential diagnosis, but a definitive diagnosis generally requires histopathological confirmation after a thyroidectomy.

An Unusual Amyloid Goiter in a 48-Year-Old Woman with Rheumatoid Arthritis, Secondary Amyloidosis and Renal Failure

“…Physical examination usually shows a so , nontender goiter that is nodular or di use. In most cases, tests show normal thyroid function, but both hyperthyroidism and hypothyroidism have been described in a few patients, usually mild, like our case [7].…”

“…Until 2000, García-Villanueva et al referred 200-250 published cases [5]. In our review, we have only found 9 cases published in the last 10 years, all of them were associated with kidney disease (CKD), with or without kidney transplant: 3 of them were associated with familial Mediterranean fever [1,6], 2 cases were associated with rheumatoid arthritis [3,7], 1 case was associated with bronchiectasis [2], another case with bronchiectasis and ankylosing spondylitis [1], and other 2 cases were associated with Crohn's disease [4] and multiple myeloma [8] ( Table 1). Hijazi et al [9] reviewed four more cases of thyrolipomatosis until 2018, publishing a new case in a 53-year-old woman with renal failure secondary to diabetic nephropathy, without anatomopathological study for amyloid.…”

“…Fat accumulation in amyloid goiters can be explained by tissue hypoxia secondary to progressive capillary and thyroid follicle destruction due to amyloid deposition. Tissue hypoxia may result in metaplasia of stromal broblasts to become adipose cells, which accumulate adipose tissue in the gland, increasing its size [1,[6][7][8].…”

“…yroid lipomatosis is clinically apparent due to a progressive enlargement of the thyroid that can involve the airway and/or upper gastrointestinal tract, producing dyspnea, dysphagia, and changes in the voice [7]. ey tend to show rapid progression, which means that di erential diagnosis must be made with malignant processes such as lymphoma or anaplastic cancer [6,7].…”

“…On MRI, fatty in ltration causes increased signal intensity both on T1-and T2-weighted images, with suppression on fat-saturated sequences. Cases with di used fatty in ltration can be di cult to di erentiate from thyrolipomatosis [7]. In a pathological examination, the thyroid reveals a loss of normal architecture with diffuse infiltration of mature adipose tissue without atypias.…”