Celiac disease is a genetically determined disease with its onset in childhood. In November 2021, a 51-year-old female patient was admitted to the Gastroenterology Department with complaints with diarrhea 5 times daily and severe protein-energy malnutrition by the type of senile kwashiorkor. Analysis of her history indicated that in March 2021, the patient took amoxicilline 500 mg twice daily, as prescribed by the local therapist, for 2 weeks, whereupon she noted the appearance of diarrhea that lasted for a month. Moreover, antibiotic-associated diarrhea was ruled out. A celiac-disease-specific histological pattern of the small bowel mucosa was revealed (the ratio of villus height to crypt depth was 1:1), as well as the titer of antibodies to recombinant tissue transglutaminase-2 IgA class >210 U/ml. This could establish a diagnosis of symptomatic celiac disease. During the gluten-free diet, the stool returned to normal; the body weight gradually began to increase. The persistent severe condition in the patient, hypokalemia, skin bronze hue, low aldosterone levels could diagnose primary hypoaldosteronism. Liver biopsy could diagnose small duct primary sclerosing cholangitis. Thus, it is important to note that the onset of celiac disease may occur may occur in people over 50 years of age; whereas primary hypoaldosteronism and primary sclerosing cholangitis may be associated with celiac disease and have a common autoimmune origin.