Multiple subcutaneous abscesses by Corynebacterium amycolatum in a patient with severe idiopathic aplastic anaemia.

Corynebacterium amycolatum is a part of the normal skin flora and has been underestimated as a pathogen. However, in recent years, the species has gained recognition as an important pathogen causing severe infections, particularly in immunocompromised patients. Nevertheless, identifying these organisms at the species level is difficult in routine clinical microbiology, leading to limited knowledge of their clinical manifestations in infectious diseases. In this study, we report a rare case of multiple subcutaneous abscesses in a patient with severe neutropenia, wherein C.amycolatum was identified as the causative organism through genotyping tests. This case highlights the importance of this organism as an aetiological agent of severe skin infections in patients with compromised immune systems.

Identification of a rare MET variant in a familial case of extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is an intraepithelial adenocarcinoma that primarily affects the genital and axillary areas in elderly individuals. A limited number of paired familial EMPD cases (i.e., parent-offspring, siblings) have been reported, whereas the genetics of these cases have not yet been adequately studied. We report the first familial case of EMPD involving three affected siblings. The tumour-only multi-gene panel testing using surgical specimens revealed a heterozygous c.2997A>C (p.Glu999Asp) nonsynonymous variant in the proto-oncogene MET (NM_000245.4) in the three affected siblings. The germline multi-gene panel testing using peripheral blood lymphocytes revealed the same missense MET variant in all five family members, including the two asymptomatic offspring (51 and 37 years of age). The MET variant we identified could be involved in EMPD carcinogenesis. Further genomic analyses of familial cases of EMPD are warranted to validate the pathogenic relevance of MET variants in EMPD development.

A case of drug-induced hypersensitivity syndrome complicated with fulminant type 1 diabetes and type 2 myocardial infarction.

Drug-induced hypersensitivity syndrome (DiHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a type of drug eruption that causes multiorgan disorders after the administration of certain drugs such as anticonvulsants. Herein, we report the case of a 66-year-old man with DiHS/DRESS complicated by fulminant type 1 diabetes (FT1D), shock, and cardiac involvement who was treated conservatively without systemic corticosteroid administration. He had taken carbamazepine for trigeminal neuralgia for 7 weeks until he noticed eruptions on his trunk. Two days after admission, he developed diabetic ketoacidosis, resulting in hypovolemic shock. The patient was diagnosed with FT1D, and insulin was administered. Additionally, the patient had a fever over 38°C, elevated white blood cells (>20 000/µL), liver dysfunction, atypical lymphocytes, and lymphadenopathy, but no evidence of viral reactivation. The lymphocyte transformation test for carbamazepine was positive, and human leukocyte antigen typing revealed the A31:01 haplotype, a risk factor for carbamazepine-induced cutaneous adverse drug reactions. Collectively, a diagnosis of atypical DiHS and a definitive case of DRESS was made. Moreover, myocardial dysfunction wall motion was observed. A close examination revealed mild coronary artery stenosis, leading to a diagnosis of type 2 myocardial infarction due to relative ischemia. The patient was carefully monitored without systemic corticosteroid administration because both clinical findings and laboratory data peaked on the same day. The patient's eruption and general condition improved, and he was discharged 4 weeks later. While most cases of DiHS/DRESS with cardiac involvement present with myocarditis, the possibility of ischemic heart disease should be considered in patients with cardiac involvement under shock.

Severe graft-versus-host disease-like enterocolitis accompanied with cytomegalovirus-reactivation in drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms.

Drug-induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe drug adverse reaction with skin eruption and visceral organ involvement. The characteristic clinical features of DIHS/DRESS are reactivation of human herpesviruses (HHV) and the development of autoimmune diseases, but their pathogenesis and associations are not yet understood. Here, we report a 66-year-old man who presented with fever, generalized erythema, diffuse lymphadenopathy, and diarrhea after 3 weeks of treatment with zonisamide. Reactivation of HHV-6 and cytomegalovirus (CMV) was detected during the clinical course. The patient was diagnosed with DIHS/DRESS and treated with systemic prednisolone, i.v. immunoglobulin therapy, and ganciclovir. However, severe enterocolitis persisted for 6 months. A series of examinations revealed features of both CMV enterocolitis, as indicated by identification of a few CMV-positive cells on immunohistochemical analysis, and graft-versus-host disease (GVHD)-like enterocolitis indicated by orange-peel appearance on endoscopic examination and histopathological loss of goblet cells. Intractable enterocolitis continued and the patient finally died of pneumonia. An autoimmune predisposition in DIHS/DRESS patients in combination with CMV reactivation was considered to trigger the severe enterocolitis of this case that showed GVHD-like features of the gastrointestinal tract. GVHD-like organ damage is a pathological condition rarely observed in DIHS/DRESS but should be recognized as one of the most severe complications of the disease.

Successful treatment of breakthrough disseminated Trichosporon asahii fungemia in a patient with acute myeloid leukemia receiving itraconazole prophylaxis.

We encountered a case of a 73-year-old man with acute myeloid leukemia who developed Trichosporon asahii systemic infection while on itraconazole prophylaxis during severe neutropenia. Cryptococcal antigen was useful for diagnosis. Although itraconazole was ineffective in protecting against trichosporonosis, treatment was successful with voriconazole following liposomal amphotericin B.

Histopathological insights into hair loss in Cronkhite-Canada syndrome: diffuse anagen-telogen conversion precedes clinical hair loss progression.

Cronkhite-Canada syndrome (CCS) is a rare disorder characterised by gastrointestinal polyposis and ectodermal changes, represented by extensive alopecia. Detailed histopathological investigations of alopecic lesions in two female CCS patients with severe hair loss revealed a marked increase in telogen hair follicles with no sign of loss or of the minaturisation or atrophy of hair follicle structures and the absence of inflammatory change, despite severe inflammation in the gastrointestinal tract. These findings suggested that hair regrowth can be expected without systemic corticosteroids, if they are not necessary for treatment of the gastrointestinal tract, and that anagen-telogen transition is an early event preceding clinical hair loss in CCS.

Trichophyton tonsurans infection manifesting as multiple concentric annular erythemas.

We report a case of dermatophytosis in a Judo wrestler caused by Trichophyton tonsurans (T. tonsurans) with clinical features that mimicked the concentric rings of tinea imbricata. Tinea imbricata is a unique dermatophytosis caused by Trichophyton concentricum (T. concentricum), observed endemically in subtropical to torrid zones and characterized by impressive concentric rings. We found three similar cases of the dermatophytosis in the literature that were reported as tinea pseudoimbricata or tinea indecisiva. All of these cases were associated with systemic or local immunosuppression, perhaps simulating the mechanism of tinea imbricata, which is known to involve the lack of delayed type hypersensitivity to T. concentricum. These cases imply that iatrogenic immunosuppression may perhaps play an important role in the development of the unique clinical features mimicking tinea imbricata. Furthermore, three of the four cases, including the presented case, were caused by T. tonsurans. It may be necessary to consider T. tonsurans infection when multiple concentric erythemas are encountered.