SÍNDROME DA SECREÇÃO INADEQUADA DE HORMÔNIO ANTIDIURÉTICO EM PACIENTES COM SÍNDROME PARANEOPLÁSICA: UMA REVISÃO INTEGRATIVA

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by the excessive production or action of antidiuretic hormone (ADH), resulting in persistent hyponatremia and inadequate urinary osmolarity increase. In oncology patients, ectopic secretion of ADH by tumor cells is responsible for the paraneoplastic manifestation of SIADH. Objective: To investigate the epidemiological and clinical profile of patients with paraneoplastic syndrome who developed SIADH. Methods: A qualitative systematic review was conducted covering the period from January 2014 to April 2024, according to the PRISMA protocol, using the databases PubMed, Virtual Health Library (BVS), ScienceDirect, and Cochrane Library. Studies were included that met the following eligibility criteria: presence of at least one combination of search terms in the title; English language; freely available full-text articles; addressing SIADH as a paraneoplastic syndrome and case reports. Abstracts, reviews, animal studies, conference proceedings, theses, and dissertations were excluded. Results: Among the 77 publications identified, only 32 met the inclusion criteria. Regarding sociodemographic profile, case reports from North America (43.75%) were more frequent. Male patients had a higher prevalence of SIADH (53.12%). The average age of the patients was 54.06 (±21.23). In the clinical profile, neuroblastoma was the most prevalent type (28.12%). The average serum sodium levels were 118.03 (±8.25) mEq/L. Urinary osmolality ranged between 266 and 902 mOsm/Kg, with a mean of 506.34 (±160.48) mOsm/Kg. Conclusion: The study highlights the relevance of SIADH as a paraneoplastic syndrome, particularly in men. Neuroblastoma was the most frequently associated condition. Future studies with more robust methodological designs are essential to deepen the understanding of SIADH in patients with paraneoplastic syndrome.