[Controversy in estimating glomerular filtration rate through traditional equations in transgender people: discussion through a case report].

Chronic kidney disease (CKD) and the number of transgender people is on the rise. Hormone replacement therapy may be associated with the development of adverse effects, including kidney disease. To report the case of a transgender patient using hormone therapy who developed CKD. Male transgender patient, 28 years old, using testosterone cypionate every 15 days, without any comorbidity. Evolved with hypertensive peaks of 160-150/110 mmHg and loss of kidney function (Ur 102 mg/dl, Cr 3.5 mg/dl, estimated Glomerular Filtration Rate (eGFR) of 22 ml/min/1.73m2 considering male gender and 16.6 ml/min/1.73m2 considering female gender). Abdominal ultrasound showed chronic parenchymal nephropathy. Due to the significant reduction in eGFR, the patient was referred for kidney transplantation, but he was not included in the list because he had a creatinine clearance of 23 ml/min/1.73m2 for males and 21.5 ml/min/1.73m2 for females in the most recent tests. Hormone replacement may have contributed to the increase in the patient's blood pressure and, consequently, to the development of CKD. There is still no well-established consensus on the best way to estimate the GFR in transgender people, and it seems to be more appropriate to consider the gender to which the person self-identifies or to perform the calculation for both genders, obtaining an estimate of the range in which the patient's GFR lies.