Acute tubulointerstitial nephritis (ATIN) is an acute kidney disease that can develop under the influence of various exogenous and endogenous factors and is manifested by inflammatory changes in the tubulointerstitial tissue of the kidneys, often accompanied by the development of acute renal kidney damage (AKI). Approximately 3–19% of all AKI cases are due to ATIN nephrobiopsy data, which indicates a difficult non-invasive diagnosis of this disease. Complaints of patients with ATIN are few and are associated with manifestations of acute renal damage: a decrease in urine volume, an increase in blood pressure (BP). Important in the diagnosis of ATIN is urinary syndrome, manifested by proteinuria less than 1 gram per day, erythrocyturia, leukocyturia, including eosinophiluria. In patients with suspected ATIN, a full physical examination is performed, attention is drawn to the appearance of pain on palpation of the kidneys, blood pressure is measured, diuresis, and the presence of edema are assessed. In laboratory diagnostics, it is necessary to investigate the level of creatinine, blood urea, general urine analysis, with instrumental — ultrasound examination of the kidneys, if indicated, a kidney biopsy is performed. Treatment is aimed at immediate cessation of the effect of the etiological factor, maintenance of waterelectrolyte balance and correction of violations of acidbase balance, blood pressure. In this regard, it is possible to use crystalloid solutions, loop diuretics (furosemide, torasemide), antihypertensive drugs in accordance with the general principles of management of patients with AKI, immunosuppressive therapy for ATIN immune genesis, with ATIN drug genesis — glucocorticoids. In the presence of appropriate indications, renal replacement therapy is performed. The prognosis of the disease often depends on timely diagnosis and appropriate treatment. The paper presents the clinical case of a female patient affected with acute tubulointerstitial nephritis.
