Published online Aug 25, 2020. doi: 10.5314/wjd.v8.i1.1
Peer-review started: January 29, 2020
First decision: May 5, 2020
Revised: May 29, 2020
Accepted: June 20, 2020
Article in press: June 20, 2020
Published online: August 25, 2020
Rhinocerebral mucormycosis (RCM) is a rare fatal fungal infection which is on the increase among immunocompromised hosts such as patients who have had hematological cancers, or have received immunosuppressive drugs, corticosteroids, or other T cell suppressing agents.
We report a case of RCM caused by Rhizopus oryzae, one of the most common opportunistic pathogens, in a patient suffering from a fourth relapse of acute myeloid leukemia. The patient developed RCM after he had received long-term antibiotic agents and corticosteroids. The pathogen was isolated three times from nasal secretions collected from the deep parts of the nasal cavity and was identified by morphology and internal transcribed spacer sequencing. Blood infection was excluded by droplet digital polymerase chain reaction and blood culture. The patient was empirically treated with caspofungin and voriconazole for several days while the lesions continued to progress. The patient was given amphotericin B in combination with caspofungin after RCM was suspected, and the lesions improved over the course of treatment, which lasted several days. However, the patient eventually died of the primary disease.
This case indicates that immunosuppressive drugs, including corticosteroids and antimetabolites in hematological tumor, do increase the risk of infections of this type. Early diagnosis, prompt and frequent surgical debridement, and treatment with amphotericin B without delay are all essential in combatting RCM.
Core tip:Rhizopus oryzae, a common but also useful environmental fungus, is usually employed in the brewing industry. Cases of rhinocerebral mucormycosis in humans are relatively rare. The case we report confirmed the pathogenic fungi through repeated molecular identification and advanced droplet digital polymerase chain reaction technology. We also discuss the patient’s laboratory test results and the early inefficacy of azole antifungal drugs. The high-risk factors and effective treatment for Rhizopus oryzae in such patients are also discussed.