Renal Dysfunction in Patients With Inflammatory Bowel Disease and the General Population (NEPHRO-IBD)

Inclusion Criteria: * Age over 18 years * Confirmed IBD based on the overall clinical picture and endoscopic examination, or no IBD (control group without IBD) * Consent to participate in the study * Cognitive abilities sufficient to complete the questionnaires Exclusion Criteria: * diabetes * dysuric symptoms suggestive of urinary tract infections * in women, menstruation (urinalysis can be performed 3 days before the onset and 3 days after the end of menstruation) * refusal to participate in all procedures performed in the study * age under 18 or over 80 * pregnancy * other serious comorbidities whose presence or exacerbation may cause abnormalities in laboratory tests suggesting kidney disease * previous surgery whose presence may cause abnormalities in laboratory tests suggesting kidney disease * extreme physical exertion within 7 days before the test (marathons, half-marathons, triathlons) and intense physical exertion - strength training - within 1 day before the test. \[moderate physical exertion such as walking, swimming, or cycling is not a contraindication\]. • Excessive alcohol consumption 14 days before the study * Inability to perform necessary tests: e.g., inability to perform an imaging test * Unavailability of data: if the study is based on registry data, exclusion of individuals for whom there is incomplete data * Dehydration * Use of nephrotoxic medications\* within a month before and during the study * Use of angiotensin inhibitors, sartans, or flozins that were introduced into treatment within \<3 months \*Nephrotoxic drugs: * Nonsteroidal anti-inflammatory drugs (NSAIDs) - occasional use is not contraindicated, but use for ≥ 10 days is an exclusion criterion * Gold salts * Penicillamine * Interferon alpha * Antituberculosis drugs (rifampicin, ethambutol, isoniazid) * Pamidronate * Biseptol * Antiviral drugs (acyclovir) * Anticonvulsants (carbamazepine, diazepam, phenobarbital) * Cyclosporine A, tacrolimus * Chinese herbs * Oncology drugs (cisplatin)