Benido Silva, VâniaPereira, Maria TeresaLeal Moreira, CarlaSantos Monteiro, SílviaInácio, IsabelCardoso, Helena2023-10-242023-10-242021-08Benido Silva V, Pereira MT, Moreira CL, Santos Monteiro S, Inácio I, Cardoso MH. Nephrotic Syndrome as a Cause of Transient Clinical Hypothyroidism. Case Rep Endocrinol. 2021;2021:5523929. doi:10.1155/2021/55239292090-651X2090-6501http://hdl.handle.net/10400.16/2847Nephrotic syndrome may trigger the onset of hypothyroidism, promoting massive urinary protein losses including thyroxine (T4) and triiodothyronine (T3) along with their binding proteins. At an early stage, a clinical and biochemical euthyroid state is expected. However, in patients with prolonged and severe proteinuria, especially with concomitant low thyroid reserve, urinary losses of free and protein-bound thyroid hormones are sufficiently pronounced to induce a subclinical or overt hypothyroidism. Despite its high prevalence in clinical practice, the literature lacks case reports of newly diagnosed clinical hypothyroidism due to NS in adults, making this condition under-recognized. We report a case of a 23-year-old man with previous normal thyroid function who developed overt hypothyroidism due to a severe nephrotic syndrome, requiring supplementation with levothyroxine (LT). After the patient had undergone bilateral nephrectomy, treatment with LT was discontinued and thyroid function normalized.engjournal article10.1155/2021/5523929