RESUMEN
Japanese spotted fever is an emerging rickettsiosis caused by Rickettsia japonica and is characterized by high fever, rash, and eschar formation. Other symptoms are often vague and nonspecific and include headaches, nausea, vomiting, and myalgia. We present a case of a 46-year-old woman with Japanese spotted fever, complicated by transient bilateral sensorineural hearing loss and presenting cutaneous IgM/IgG immune complex vasculitis. The patient was admitted with a history of several days of high fever, generalized skin erythema, and hearing impairment. Laboratory findings revealed thrombocytopenia and elevated liver enzyme and C-reactive protein levels. Pure-tone audiometry revealed bilateral sensorineural hearing loss, and a skin biopsy revealed leukocytoclastic vasculitis with deposition of C3 and IgM on the vessel walls. Under the tentative diagnosis of rickettsiosis, scrub typhus, or Japanese spotted fever, the patient was treated with minocycline, and her symptoms improved within approximately 10 days. A definitive diagnosis was made on the basis of a serological test showing increased antibody levels against Rickettsia japonica. Japanese spotted fever can cause transient sensorineural hearing loss, a rare complication that presents with cutaneous IgM/IgG immune complex vasculitis.
RESUMEN
Nontuberculous mycobacteria cause a wide range of infections, including cutaneous infections, in both immunocompromised and immunocompetent patients. Although pulmonary nontuberculous mycobacterial infections have increased significantly in Japan in recent years, there is less evidence on clinical and microbiological characteristics of cutaneous nontuberculous mycobacterial infections in Japan. We reviewed 86 Japanese cases reported between July 2016 and November 2021 and analyzed them in conjunction with the eight patients from our institution who were diagnosed with cutaneous nontuberculous mycobacterial infections by culture between 2015 and 2021. In the aggregate series, the average patient age was 60 years, and the ratio of immunocompromised hosts was 53%, both of which were higher than those in previous reports from other countries. No female predominance was observed, unlike in pulmonary nontuberculous mycobacteria infections. Rapidly growing mycobacteria accounted for 58% of the cases (n = 54), whereas slowly growing mycobacteria for 43% (n = 40). Mycobacterium marinum (also known as Mycobacteroides marinum) (n = 20, 21%) was the most common cause, followed by Mycobacterium chelonae (n = 18, 19%), Mycobacterium abscessus (also known as Mycobacteroides abscessus) (n = 15, 16%), and Mycobacterium ulcerans (n = 11, 12%). While clinical appearance was variable, M ulcerans infections usually presented with ulcers, while nodules were common among infections caused by M chelonae and M marinum. Disseminated infections involving multiple organs were observed in 23 patients (24%). Thirty-two cases (30%) were preceded by exposure, including raising or handling fish, trauma, and invasive medical procedures. Most patients were treated with more than two antibiotics and responded to therapy.