Clinical Characteristics and Treatment Outcomes of Autoimmune Enteropathy in Children.

Background/Aims Pediatric autoimmune enteropathy (AIE) is a rare disease that causes intractable diarrhea in children. Through this study, we present seven cases of pediatric patients diagnosed with AIE. Our study aids in understanding the clinical and genetic characteristics of this rare genetic condition and the considerations in its management. Methods From December 1996 to September 2019, seven cases who were diagnosed as AIE in Seoul National University Children's Hospital were retrospectively analyzed. The clinical sources of all AIE cases were reviewed, including electronic medical records, histopathologic material, radiologic images, and laboratory findings. Results Initial symptoms were diarrhea (in six children) and hematochezia (in one patient). Later, all patients had severe diarrhea which started in the early months of life. Among the five patients tested on gene studies, forkhead box P3 (FOXP3) mutations were identified in four patients, and all of them were males. All patients initially received steroid treatment. Patients with a partial and transient response were considered for alternative agents. Three patients (42.9%) remained in remission under tacrolimus monotherapy, one patient (14.3%) with tacrolimus and prednisolone combination therapy, one patient (14.3%) with tacrolimus, prednisolone, and cyclosporine combination therapy, one patient (14.3%) had died of fulminant hepatitis, and one patient (14.3%) had died of septic shock. All patients were treated with tacrolimus for more than 1 year. Estimated glomerular filtration rate (eGFR) decreased in six patients (85.7%) and increased in one patient (14.3%). Conclusions In this study, all patients treated with tacrolimus showed amelioration of symptoms. However, histological characteristics did not correlate with symptom improvement. Therefore, the efficacy of treatment can be assessed by symptoms and frequent endoscopic biopsies are not required. For long-term use of tacrolimus, close observation of eGFR is recommended to detect nephrotoxicity early. [ABSTRACT FROM AUTHOR]