Keio Journal of Medicine

We encountered a-27-year-old female patient who developed refractory severe headache and photophobia after the first dose of COVID-19 vaccine. Despite her prior history of migraine, we diagnosed COVID-19 vaccine-induced aseptic meningitis. Symptoms were significantly resolved after methylprednisolone therapy. On reviewing the literature, we could find only nine similar cases, with over half of them affecting women aged 20-40 years. Although uncommon, aseptic meningitis should be suspected in patients with persistent or delayed onset of headache following COVID-19 vaccination...

Neurofibromatosis 1 (NF1), also known as von Recklinghausen disease, is one of the most common neurocutaneous genetic disorders. Loss of function of the NF1 gene results in overactivation of the RAS/MAPK pathway, leading to neurocutaneous manifestations and osseous abnormalities. Because of medical progress, molecular testing for NF1 after genetic counseling is now available in Japan. In addition, revised diagnostic criteria for NF1 were proposed by NF1 experts of an international panel in 2021. Because the overall degree of severity and manifestations in each patient are not predictable, age-specific annual monitoring and patient education by a multidisciplinary team are important for the management of NF1...

Constipation is a complicated condition. Chronic constipation is diagnosed when constipation occurs for more than 3 months. Chronic constipation is classified using patient symptoms and the pathophysiology. New therapeutic agents to treat chronic constipation have recently been approved in Japan. However, treatments for constipation that is refractory to traditional laxatives have been approved, an algorithm for the treatment of chronic constipation has not yet been developed. The accumulation of knowledge and data is necessary to develop a new algorithm...

Gorlin syndrome and Cowden syndrome are hereditary diseases that are characterized by multiple malignancies, cutaneous symptoms, and various other abnormalities. Both disorders are caused by a mutation of the gene that regulates cell proliferation and growth, resulting in tumorigenesis. Representative mutations are mutation in the patched 1 gene (PTCH1) in Gorlin syndrome and mutation in the phosphatase and tensin homolog deleted from chromosome 10 (PTEN) gene in Cowden syndrome. Making a diagnosis of these diseases in the early years of life is important because detection of malignancies at an early stage is linked to improved prognosis...

Tuberous sclerosis complex (TSC) is an autosomal dominant inherited disease characterized by systemic hamartomas, neuropsychiatric symptoms known as TAND (TSC-associated neuropsychiatric disorders), and vitiligo. These symptoms are attributed to the constant activation of mechanistic target of rapamycin complex 1 (mTORC1) caused by genetic mutations in the causative genes TSC1 or TSC2. The elucidation of the pathogenesis of this disease and advances in diagnostic technologies have led to dramatic changes in the diagnosis and treatment of TSC...

The sensory and immune systems have been studied independently for a long time, whereas the interaction between the two has received little attention. We have carried out research to understand the interaction between the sensory and immune systems and have found that inflammation and bone destruction caused by fungal infection are suppressed by nociceptors. Furthermore, we have elucidated the molecular mechanism whereby fungal receptors are expressed on nociceptors and skin epithelium, how they cooperate to generate fungal pain, and how colitis and bone metabolism are regulated by mechanosensors expressed on the gut epithelium...

The hair follicle is an appendage of the skin that undergoes hair cycles throughout life. Recently, numerous genes expressed in the hair follicles have been identified, and variants in some of these genes are now known to underlie hereditary hair diseases in humans. Hereditary hair diseases are classified into non-syndromic and syndromic forms. In the Japanese population, the non-syndromic form of autosomal recessive woolly hair, which is caused by founder pathogenic variants in the lipase H (LIPH) gene, is the most prevalent hereditary hair disease...

Our Research Group for Rare and Intractable Skin Diseases operates within the Project for Research on Intractable Diseases of the Ministry of Health, Labour, and Welfare of Japan and is conducting research on eight rare intractable skin diseases. Five of these are monogenic disorders (epidermolysis bullosa, congenital ichthyoses, oculocutaneous albinism, pseudoxanthoma elasticum, and hereditary angioedema), and for a sixth [generalized pustular psoriasis (GPP)], genetic predisposing factors are important. This review introduces our activities for raising public awareness of these six intractable hereditary skin diseases and summarizes our recent achievements in clarifying the situation of medical treatments for these diseases in Japan...

Inflammatory bowel diseases (IBD) are currently recognized to involve chronic intestinal inflammation in genetically susceptible individuals. Patients with IBD mainly develop gastrointestinal inflammation, but it is sometimes accompanied by extraintestinal manifestations such as arthritis, erythema nodosum, episcleritis, pyoderma gangrenosum, uveitis, and primary sclerosing cholangitis. These clinical aspects imply the importance of interorgan networks in IBD. In the gastrointestinal tract, immune cells are influenced by multiple local environmental factors including microbiota, dietary environment, and intercellular networks, which further alter molecular networks in immune cells...

The number of patients with chronic kidney disease (CKD) is on the rise worldwide, and there is urgent need for the development of effective plans against the increasing incidence of CKD. Podocytes, glomerular epithelial cells, are an integral part of the primary filtration unit of the kidney and form a slit membrane as a barrier to prevent proteinuria. The role of podocytes in the pathogenesis and progression of CKD is now recognized. Podocyte function depends on a specialized morphology with the arranged foot processes, which is directly related to their function...

Gain-of-function mutations had been believed to function as a single mutation in oncogenes, although some secondary mutations, such as EGFR T790M mutations, are frequently acquired in patients that are resistant to tyrosine kinase inhibitor treatment. Recently, we and other investigators have reported that multiple mutations (MMs) frequently occur in the same oncogene before any therapy. In a recent pan-cancer study, we identified 14 pan-cancer oncogenes (such as PIK3CA and EGFR) and 6 cancer type-specific oncogenes that are significantly affected by MMs...

A 75-year-old man underwent distal gastrectomy for advanced gastric cancer in September 2018. During the adjuvant chemotherapy, computed tomography (CT) revealed recurrence sites in the liver and para-aortic lymph nodes. Therefore, chemotherapy was initiated. After first-line (capecitabine with oxaliplatin) and second-line (paclitaxel with ramucirumab) treatments, nivolumab was used as third-line chemotherapy. This treatment showed a strong effect against the tumor. However, following an immune-related adverse effect (irAE) because of nivolumab, the therapy was halted...

The standard method for sleep state classification is thresholding the amplitudes of electroencephalography (EEG) and electromyography (EMG) data, followed by manual correction by an expert. Although popular, this method has some shortcomings: (1) the time-consuming manual correction by human experts is sometimes a bottleneck hindering sleep studies, (2) EEG electrodes on the skull interfere with wide-field imaging of the cortical activity of a head-fixed mouse under a microscope, (3) invasive surgery to fix the electrodes on the thin mouse skull risks brain tissue injury, and (4) metal electrodes for EEG and EMG recording are difficult to apply to some experimental apparatus such as that for functional magnetic resonance imaging...

Food protein-induced enterocolitis syndrome (FPIES) is a type of non-IgE-mediated gastrointestinal food allergy. FPIES is characterized by repetitive vomiting without classic IgE-mediated allergic skin or respiratory symptoms 1-4 h after causative food ingestion. The condition may be classified as acute or chronic, typical or atypical, and liquid or solid according to the course of symptoms, presence of IgE antibodies, and causative food, respectively. Since the development of international consensus guidelines in 2017, epidemiological studies have been conducted in many countries...

Patients with tracheostomy who undergo a full sternotomy have an increased risk of mediastinitis and sternal infection. This report describes a reoperative aortic valve replacement (re-AVR) for structural valve deterioration (SVD) through a lower hemisternotomy. This procedure was performed on a 71-year-old man with a tracheostomy who had previously undergone a Bentall procedure with a bioprosthetic valve to replace an enlarged ascending aortic aneurysm. Comorbidities included chronic renal failure requiring hemodialysis...

This study investigated lifestyle changes and the self-reported mental health status of Japanese community residents during the COVID-19 pandemic. Differences in demography, daily lifestyle changes, and approaches to problem solving were analyzed in two age cohorts (<60 vs ≥60 years). The prevalence of moderate/increased psychological distress was 31.7%, with no significant difference between the cohorts. Compared with the pre-COVID-19 era, more than 80% of the participants stopped eating out and spent more time at home, and more than 70% used public transport less frequently...

Emerging infections are caused when microorganisms that are maintained in a reservoir where they cause no harm, transmit from the reservoir to a new host. I have been studying the replication, molecular basis for pathogenesis, and host responses to emerging viruses, including influenza virus, Ebola virus, and SARS-CoV-2, and using the knowledge gained from these studies to develop antivirals and vaccines.Influenza viruses cause epidemics every winter, but occasionally new influenza viruses emerge and spread worldwide (pandemic)...

The quest to cure cancer has been one of the Holy Grails of medicine. The discovery I am going to share with you, CAR T cells, is a promising new form of therapy of cancer that offers the prospect of curing cancer using the immune system. CAR T cells are the first form of synthetic biology to enter the practice of medicine. The notion of using the immune system to fight cancer is an old idea. Over a century ago, bacteria were ground up and injected into patients with late-stage cancers, and occasionally the cancer would disappear...

Our understanding of the biology of the intestinal epithelium has advanced since the establishment of an organoid culture system. Although organoids have enabled investigation of the mechanism of self-renewal of human intestinal stem cells in vitro, it remains difficult to clarify the behavior of human normal and diseased intestinal epithelium in vivo. Recently, we developed a xenotransplantation system in which human intestinal organoids are engrafted onto epithelium-depleted mouse colons. This xenograft recapitulated the original tissue structures...

Uterus transplantation (UTx) is now a potential option to allow women with uterine factor infertility to give birth. However, UTx is still at an experimental stage, and basic animal studies, including in non-human primates, are needed for the accumulation of data prior to clinical application. Considering that UTx may provide new hope to Japanese women, we launched UTx research in 2009 and have since accumulated a large archive of results in the UTx research field. Furthermore, we have carried out various activities aimed at the implementation of clinical applications of UTx in Japan while clarifying the ethical and social issues involved...