We report the cases of two patients who had psychotic problems and were addicted to the use of cooking oil for eczema treatment. Case 1 was that of a 79-year-old woman who had a bipolar disorder and frequentlyused cooking oil topically when her skin was dry. Pruritic erythema developed in the trunk 3 months before she visited our department. She presented with pruritic, confluent erythematous macules over the trunk and the extremities. Histopathology revealed a mild spongiotic change and liquefaction in the epidermis and perivascular lymphocytic infiltrates in the upper dermis ; we established a diagnosis of eczematous dermatitis due to inappropriate use of cooking oil. She stopped topical use of cooking oil and was topically treated with glucocorticoid ointment and antihistamine, which relieved her symptoms in one week. Case 2 was that of a 39-year-old woman who had a delusional disorder and experienced atopic dermatitis since childhood. She had a steroid phobia ; therefore, she used cooking oil as an emollient for more than 9 years. She was admitted to our hospital at the age of 33-year-old ; her condition improved with the use of a moisturizer ; however, she discontinued moisturizer use thereafter. She was admitted to the psychiatry department in our hospital because her psychiatric condition worsened, as evidenced by the fact that she perpetrated domestic violence on her father. She was then referred to our department. At the visit, she presented with erythroderma and several scratch marks due to irritation caused by topical cooking oil. However, she refused to accept any dermatological treatment, including glucocorticoid ointment. She did not even take antipsychotic drugs, leading to aggravation of her delusional disorder. Meanwhile, her condition improved temporarily with the use of oral cyclosporine. However, she refused treatment again, and the eczema recurred. Eventually, erythroderma persisted with an abuse of cooking oil because her psychiatric condition prevented treatment compliance for the skin disease owing to refusal of advice and suggestions from the dermatologists and co-medical workers.

A 30-year-old man presented with erythema and erosion on the lips, hard palate mucosa, and glans for five days. He also had an erythematous patch on the dorsal aspect of the left hand and the right thigh. He presented with the same condition three times in 9 months. Fixed eruption was considered on the basis of the clinical findings. A histopathological examination of the left hand revealed liquefaction degeneration at the epidermal-dermal junction and necrotic keratinocytes in the epidermis consistent with fixed eruption. After a detailed inquiry, we suspected fixed eruption due to food. Open-patch tests with tonic water, avocado and coriander performed on the lip were all negative. A patch test of 1%-quinine performed on the lesion of the dorsal aspect of the left hand was positive. Thus, he was diagnosed with fixed food eruption (FFE) due to quinine. Quinine is often added to tonic water as a bitterness component. FFE stands for fixed eruption due to food and food additives, including quinine. A summary of previously reported cases suggests that quinine-induced FFE is more likely to occur on the lips and oral mucosa compared to FFE induced by other foods. It is necessary to suspect foods as the cause of fixed eruption if the patient has no particular history of drug intake.

Case 1 was a 43-year-old Japanese man who presented with erythrodermic, scaly lesions on the trunk and face and marked palmoplantar hyperkeratosis and fissures. His parents were consanguineous. He reported that he has had keratotic erythroderma since early childhood. He had been given the diagnosis of pityriasis rubra pilaris (PRP) in childhood and has been treated with topical corticosteroids and oral etretinate since that time. As he became older, the erythema on his face and trunk improved except for palmoplantar hyperkeratosis. Histopathological findings from a biopsy specimen taken from a lesion on the chest at the present visit showed hyperkeratosis with focal dyskeratosis, epidermal hyperplasia, loss of the granular layer and formation of keratin plugs in the infundibulum of hair follicles, which were compatible with PRP. The skin rash was relieved by emollient ointments, oral etretinate and whole body irradiation with narrow band ultraviolet B. Case 2 was a 45-year-old woman, who was an older sibling of case 1, and who presented with palmoplantar hyperkeratosis and desquamated erythema over the entire body, which she has had since childhood. Treatments with etretinate and cyclosporine resulted in some improvement of her lesions ; however, hyperkeratotic erythematous lesions remained in the palmoplantar regions and extremities. Whole-exome-sequencing analysis of genomic DNA from the siblings revealed that each sibling was homozygous for a novel missense mutation (c.4601C＞T, p. Thr1534Met) in the ABCA12 gene, while no mutation was found in the CARD14 gene which is one of the genes responsible for PRP. Therefore, we made a final diagnosis of congenital ichthyosis erythroderma in the siblings.

A 20-year-old woman had acquired a reddish plaque on her buttock since she was 3 years old. Subsequently, palmoplantar reddish plaque followed and she was diagnosed as having psoriasis bya dermatologist. She visited our department because her palmoplantar lesions gradually worsened. Oral apremilast dramatically improved her palmoplantar symptoms. Apremilast is a phosphodiesterase 4 inhibitor released in 2017 in Japan. Clinical trial of apremilast revealed that palmoplantar psoriasis physician global assessment score one or more became 0 in 46% of patients (placebo 25%). Palmoplantar psoriasis is often refractory by topical and/or ultravilolet therapy. As the first line of systemic therapy, apremilast can be a new option for this condition.

Here, we report a case of cutaneous endometriosis. A 39-year-old woman presented with a subcutaneous nodule in the right inguinal region with a 1-month history. The patient had undergone infertility treatment for 9 years before she visited us. Computed tomography (CT) analysis revealed a subcutaneous nodule with an indistinct border, ruling out the possibility of adenomyosis of the uterus or inguinal hernia. We performed surgical excision of the nodule. Histopathologically, the nodule was composed of glandular ducts and surrounding stroma that was directly connected to the round ligament of the uterus. After ruling out the possibility of an apocrine gland or ectopic mammary gland on the basis of an immunohistochemistry examination, endometriosis was diagnosed. Cutaneous endometriosis should be considered in the differential diagnosis of a patient with an inguinal subcutaneous nodule.

A 61-year-old man was diagnosed with polymyositis, and treatment with prednisolone (PSL) was initiated in May 2013. Computed tomography (CT) analysis revealed left cervical and axillary lymphadenopathy before the treatment, but the findings had been followed-up. However, the lymph nodes became larger, and the biopsy revealed that they were malignant melanoma. Further examination did not reveal any primary lesion. There was no clinical improvement after DTIC therapy and DAC-Tam-Feron therapy ; vemurafenib was administered from May 2015. After the initiation of vemurafenib, the size of the metastatic lesions reduced immediately. However, we changed vemurafenib to nivolumab at a dose of 2 mg/kg every 3 weeks because of disease progression. The patient complained of fatigue and his serum myogenic enzyme levels elevated after the second administration of nivolumab. These signs and symptoms were considered to indicate the exacerbation of polymyositis. Nivolumab was continued with PSL at 20 mg ; his condition improved, and his serum myogenic enzyme levels rapidly decreased. However, his metastatic lesions did not reduce after five courses of nivolumab. Furthermore, ipilimumab was also ineffective ; thereafter, dabrafenib and trametinib treatment was initiated in June 2016. The tumors were well controlled ; however, he became resistant to the drugs. Despite treatment, he died of melanoma in July 2017. Although an immune checkpoint inhibitor exacerbated a pre-existing autoimmune disorder, we were able to continue the therapy with appropriate management.

A 56-year-old man with a history of pervasive developmental disorder complained of a scrotal mass for five years. The verrucous tumor not only covered the scrotum and the penile shaft but also extended to the prepuce close to the glans, with crusts. Histologically, the tumor cells consisted of atypical keratinocytes with cancer pearl formation and surface koilocyte formation, leading to the diagnosis of a Buschke-Löwenstein tumor. The nuclei of some of the tumor cells were immunoreactive to anti-human papilloma virus antibodies. Three courses of CA chemotherapy (combined therapy of cisplatin and doxorubicin) and 60 Gy of broad radiotherapy successfully cured the lesion. No recurrence was observed after 24 months.

A 57-year-old woman visited a hilly area to pursue her hobby of digging bamboo shoots. She suffered tick bites on her left thigh and right axilla at 16 and 8 days before the first visit, respectively. She started experiencing general malaise at 5 days before the visit and developed spotted erythema on the lower limbs on the day before the visit. She visited a dermatology clinic on the next morning with a body temperature of 37℃ (which rose to 38.5℃ later), and she was referred to our hospital with a clinical diagnosis of Japanese spotted fever on the same day. The disease-related symptoms (malaise, spotted erythema, and fever) and blood test abnormalities subsided with the oral administration of minocycline at a dose of 200 mg/day. The detection of Rickettisia japonica DNA from the black crust on the right axilla and significant elevation of the specific sera IgM and IgG confirmed the clinical diagnosis. The earliest possible treatment is recommended to prevent severe outcomes of Japanese spotted fever. Fever, malaise, erythema, joint pain, and nausea are the early symptoms, the first three of which are the most common ones. We reviewed and analyzed a total of 90 reported cases of Japanese spotted fever from 1989 to 2018 April to find useful related symptoms for the earliest possible treatment. Our analyses indicated that fever and erythema are useful symptoms for preventing severe outcomes with early intervention.

We report the case of tinea nigra caused by Annulohypoxylon sp. between the right 2nd, 3rd, 4th, and 5th toes and on the right 4th toenail of a 93-year-old man. Clinically, it was a non-inflamed, linear, patchy, black-brown pigmented spot that was more black-toned than those in the reported cases. At the time of recurrence of the nail plate lesion, a pale brown linear pigmented spot with a mosaic-like appearance was observed via dermoscopy. Microscopic examination from interdigit and nail plate revealed numerous black-brown hyphae. In the culture of the scales, the colonies turned from black to white villi at each passage. In the slide culture, only hyphae grew ; the spores and conidia did not grow. Hortaea werneckii and Venezuelan endemic Stenella araguata were ruled out. Genetic analyses of the ITS-D1/D2 region from the culture samples led to an identification of Annulohypoxylon sp. There have been no cases of infection in humans with plant rot fungus species. The possibility of contamination was ruled out because of obvious clinical features of tinea nigra, and only Annulohypoxylon sp. could be isolated and cultured. We hypothesized that the infection was from the living environment. To the best our knowledge, this is the first case in the world of tinea nigra caused by Annulohypoxylon sp. Although an antifungal agent was applied topically, relapse was observed in both the toe web and the nail plate. We recommend that tinea nigra caused by this species should be regarded as an incurable disease.

Dipeptidyl peptidase-4 (DPP-4) inhibitors are used to treat diabetes mellitus. Bullous pemphigoid, associated with the use of such inhibitors, is characterized by blistering without erythema and low anti-BP180 NC16a antibody titers. However, no study has yet assessed the characteristics of bullous pemphigoid associated with diabetes mellitus. Here, we divided 93 pemphigoid patients treated at the Ehime University Graduate School of Medicine, Department of Dermatology, over the past 10 years into three groups by the presence or absence of diabetes at pemphigoid onset and a history of oral DPP-4 inhibitor prescription. We assessed clinical features, eosinophil numbers in peripheral blood, anti-BP180 NC16a antibody titers, and treatments. Bullous pemphigoid patients with diabetes mellitus exhibited the characteristic features of pemphigoid patients that are associated with the use of DPP-4 inhibitors. Our findings suggest that DPP-4 inhibitors trigger pemphigoid onset in patients with diabetes mellitus.

John McGrath (MD, FRCP, FMedSci) holds the Mary Dunhill Chair in Cutaneous Medicine at the St John's Institute of Dermatology, King's College London, and is Head of Department for the St John's Institute of Dermatology and its Genetic Skin Disease Unit, as well as Honorary Consultant Dermatologist to the Guy's and St Thomas' NHS Foundation Trust in London. He is also Honorary Professor of Dermatologyat the Universityof Dundee.