Mucormycosis Caused by Unusual Mucormycetes, Non-Rhizopus, -Mucor, and -Lichtheimia Species

<jats:title>SUMMARY</jats:title><jats:p><jats:named-content content-type="genus-species">Rhizopus</jats:named-content>,<jats:named-content content-type="genus-species">Mucor</jats:named-content>, and<jats:named-content content-type="genus-species">Lichtheimia</jats:named-content>(formerly<jats:named-content content-type="genus-species">Absidia</jats:named-content>) species are the most common members of the order Mucorales that cause mucormycosis, accounting for 70 to 80% of all cases. In contrast,<jats:named-content content-type="genus-species">Cunninghamella</jats:named-content>,<jats:named-content content-type="genus-species">Apophysomyces</jats:named-content>,<jats:named-content content-type="genus-species">Saksenaea</jats:named-content>,<jats:named-content content-type="genus-species">Rhizomucor</jats:named-content>,<jats:named-content content-type="genus-species">Cokeromyces</jats:named-content>,<jats:named-content content-type="genus-species">Actinomucor</jats:named-content>, and<jats:named-content content-type="genus-species">Syncephalastrum</jats:named-content>species individually are responsible for fewer than 1 to 5% of reported cases of mucormycosis. In this review, we provide an overview of the epidemiology, clinical manifestations, diagnosis of, treatment of, and prognosis for unusual Mucormycetes infections (non-<jats:named-content content-type="genus-species">Rhizopus</jats:named-content>, -<jats:named-content content-type="genus-species">Mucor</jats:named-content>, and -<jats:named-content content-type="genus-species">Lichtheimia</jats:named-content>species). The infections caused by these less frequent members of the order Mucorales frequently differ in their epidemiology, geographic distribution, and disease manifestations.<jats:named-content content-type="genus-species">Cunninghamella bertholletiae</jats:named-content>and<jats:named-content content-type="genus-species">Rhizomucor pusillus</jats:named-content>affect primarily immunocompromised hosts, mostly resulting from spore inhalation, causing pulmonary and disseminated infections with high mortality rates.<jats:named-content content-type="genus-species">R. pusillus</jats:named-content>infections are nosocomial or health care related in a large proportion of cases. While<jats:named-content content-type="genus-species">Apophysomyces elegans</jats:named-content>and<jats:named-content content-type="genus-species">Saksenaea vasiformis</jats:named-content>are occasionally responsible for infections in immunocompromised individuals, most cases are encountered in immunocompetent individuals as a result of trauma, leading to soft tissue infections with relatively low mortality rates. Increased knowledge of the epidemiology and clinical presentations of these unusual Mucormycetes infections may improve early diagnosis and treatment.</jats:p>