Since fiscal year 2015, our hospital has conducted regular hospital inspections by a medical engineer (ME). About 1 year after the start of this inspection, fungi and common bacteria were detected, so we searched for the cause and report here successful cleanup of the incubator. When the incubator was cleaned during a periodic inspection, the ME discovered that dirt mainly adhered to the fan and the bed rest. Also, fungi were detected from the fans, so the ME cleaned and disinfected all the fans and then switched to a process of washing the central supply room. Following this process, bacteria were no longer detected from inside the incubator, but they have been consistently detected from the fans. We have no reported cases of patient infection, and we believe this is because the ME is responsible for periodic cleaning against bacteria and for conducting inspections. This demonstrates that successful cleaning of the incubator led to control of the spread of infectious diseases.

Autoimmune enteropathy (AIE) is a rare disease, characterized by intractable diarrhea, villous atrophy of the small intestine, and the presence of circulating anti-enterocyte autoantibodies. Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, and mutations in FOXP3, which is a master gene of regulatory T cells (Tregs), are major causes of AIE. Recent studies have demonstrated that mutations in other Treg-associated genes, such as CD25 and CTLA4, show an IPEX-like phenotype. We present the case of a 13-year-old girl with CTLA4 haploinsufficiency, suffering from recurrent immune thrombocytopenic purpura and intractable diarrhea. We detected an autoantibody to the AIE-related 75 kDa antigen (AIE-75), a hallmark of the IPEX syndrome, in her serum. She responded well to a medium dose of prednisolone and a controlled dose of 6-mercaptopurine (6-MP), even after the cessation of prednisolone administration. Serum levels of the soluble interleukin-2 receptor and immunoglobulin G (IgG) were useful in monitoring disease activity during 6-MP therapy. In conclusion, autoimmune-mediated mechanisms, similar to the IPEX syndrome, may be involved in the development of enteropathy in CTLA4 haploinsufficiency. Treatment with 6-MP and monitoring of disease activity using serum levels of soluble interleukin-2 receptor and IgG is suggested for such cases.