Primary Cutaneous Mucormycosis Caused by Rhizopus oryzae: A Case Report and Review of Literature

Cutaneous mucormycosis with suspected dissemination in a patient with metastatic adrenocortical carcinoma

Mucormycosis is a frequently lethal fungal infection that most commonly affects patients with poorly controlled diabetes or other immunosuppressed states. We report the case of a suspected disseminated Rhizopus infection in a patient who was pursuing naturopathic treatment including mud baths for metastatic adrenocortical carcinoma. He was empirically treated with liposomal amphotericin B but opted to stop treatment following multiorgan failure. The patient passed away on the tenth day of his hospital admission.

Primary cutaneous mucormycosis due to Rhizopus arrhizus in an immunosuppressed patient with paroxysmal nocturnal haemoglobinuria

OBJECTIVE

We present a case of primary cutaneous mucormycosis in a patient with bone marrow failure secondary to paroxysmal nocturnal haemoglobinuria (PNH).

CLINICAL CASE

A 60-year-old male patient with a history of PNH, complicated to a severe aplastic anaemia, presented to the emergency department complaining of papules on the lower limbs that rapidly turned into necrotic plaques within 2 months. Histopathological examination showed granulomatous and suppurative dermatitis with tissue necrosis and the presence of non-septate hyphae. Molecular identification was achieved by amplification and sequencing of the 18S-ITS1-5.8S-ITS2-28S rRNA region using the polymerase chain reaction. The sequence showed 100% identity with Rhizopus arrhizus. The patient received treatment with liposomal amphotericin B and surgical debridement. Nonetheless, the patient suffered from severe low red blood cells and platelets and also underwent septic shock; he died 6 days after admission to the hospital.

CONCLUSION

Mucormycosis in the setting of immunosuppression is challenging. Upon suspicion of a diagnosis, immediate treatment is required. Adjunctive therapies may be considered; however, the case fatality rate remains high.

Transcontinental Dispersal of Nonendemic Fungal Pathogens through Wooden Handicraft Imports

This study examined the viability and diversity of fungi harbored in imported wooden handicraft products sold in six retail stores in Florida, United States. Despite being subjected to trade regulations that require various sterilization/fumigation protocols, our study demonstrates high survival and diversity of fungi in wood products originating from at least seven countries on three continents. Among these fungi were nonendemic plant and human pathogens, as well as mycotoxin producers. Several products that are sold for use in food preparation and consumption harbored a novel (to North America) plant and human pathogen, Paecilomyces formosus. In addition, a high number of species isolated were thermophilic and included halophilic species, suggesting adaptability and selection through current wood treatment protocols that utilize heat and/or fumigation with methyl-bromide. This research suggests that current federal guidelines for imports of wooden goods are not sufficient to avoid the transit of potential live pathogens and demonstrates the need to increase safeguards at both points of origin and entry for biosecurity against introduction from invasive fungal species in wood products. Future import regulations should consider living fungi, their tolerance to extreme conditions, and their potential survival in solid substrates. Mitigation efforts may require additional steps such as more stringent fumigation and/or sterilization strategies and limiting use of wood that has not been processed to remove bark and decay. IMPORTANCE This study, the first of its kind, demonstrates the risk of importation of nonendemic foreign fungi on wooden handicrafts into the United States despite the application of sanitation protocols. Previous risk assessments of imported wood products have focused on potential for introduction of invasive arthropods (and their fungal symbionts) or have focused on other classes of wood products (timber, wooden furniture, garden products, etc.). Little to no attention has been paid to wooden handicrafts and the fungal pathogens (of plants and humans) they may carry. Due to the large size and diversity of this market, the risk for introduction of potentially dangerous pathogens is significant as illustrated by the results of this study.

Development of a Monoclonal Antibody and a Serodiagnostic Lateral-Flow Device Specific to Rhizopus arrhizus (Syn. R. oryzae), the Principal Global Agent of Mucormycosis in Humans

Mucormycosis is a highly aggressive angio-invasive disease of humans caused by fungi in the zygomycete order, Mucorales. Though a number of different species can cause mucormycosis, the principal agent of the disease worldwide is Rhizopus arrhizus, which accounts for the majority of rhino-orbital-cerebral, pulmonary, and disseminated infections in immunocompromised individuals. It is also the main cause of life-threatening infections in patients with poorly controlled diabetes mellitus, and in corticosteroid-treated patients with SARS-CoV-2 infection, where it causes the newly described disease, COVID-19-associated mucormycosis (CAM). Diagnosis currently relies on non-specific CT, a lengthy and insensitive culture from invasive biopsy, and a time-consuming histopathology of tissue samples. At present, there are no rapid antigen tests for the disease that detect biomarkers of infection, and which allow point-of-care diagnosis. Here, we report the development of an IgG1 monoclonal antibody (mAb), KC9, which is specific to Rhizopus arrhizus var. arrhizus (syn. Rhizopus oryzae) and Rhizopus arrhizus var. delemar (Rhizopus delemar), and which binds to a 15 kDa extracellular polysaccharide (EPS) antigen secreted during hyphal growth of the pathogen. Using the mAb, we have developed a competitive lateral-flow device (LFD) that allows rapid (30 min) and sensitive (~50 ng/mL running buffer) detection of the EPS biomarker, and which is compatible with human serum (limit of detection of ~500 ng/mL) and bronchoalveolar lavage fluid (limit of detection of ~100 ng/mL). The LFD, therefore, provides a potential novel opportunity for the non-invasive detection of mucormycosis caused by Rhizopus arrhizus.

Bioburden contamination and Staphylococcus aureus colonization associated with firefighter's ambulances

Ambulance vehicles are an essential part of emergency clinical services. Bioburden control in ambulances, through cleaning and disinfection, is crucial to minimize hospital-acquired infections, cross contamination and exposure of patients and ambulances' crew. In Portugal, firefighter crews are responsible, besides fire extinction, for first aid and urgent pre-hospital treatment. This study assessed the bioburden in Portuguese firefighters' ambulances with a multi-approach protocol using active and passive sampling methods. Fungal resistance profile and mycotoxins detection in ambulances' ambient, and S. aureus (SA) prevalence and resistance profile in ambulances' ambient and colonization in workers were also investigated. Toxigenic fungi with clinical relevance, namely Aspergillus section Fumigati, were found on ambulance's air in the hazardous dimension range. Interestingly, surface contamination was higher after cleaning in several sampling sites. Prevalence of S. aureus was 3% in environmental samples, of which 2% were methicillin-sensitive (MSSA) and 1% methicillin-resistant (MRSA). About 2.07 fungal species were able to grow in at least one azole, ranging from one (44% samples) to five (6% samples) species in each azole. Mycotoxins were detected in mops and electrostatic dust cloths. Colonization by S. aureus in the firefighter crew was observed with a high associated prevalence, namely 48%, with a 24% prevalence of MSSA (8/33) and 21% of MRSA (7/33). Additional studies are needed to determine the potential risk of infection transmission between different vehicle fleets and under varying conditions of use. This will strengthen the paramedic sector's mission to save lives without putting their own health and safety at risk.

The Curious Case of "Case Report" of Infections Caused by Human and Animal Fungal Pathogens: An Educational Tool, an Online Archive, or a Format in Need of Retooling

Case reports describe the unusual occurrence and complications of diseases, diagnostic challenges, and notable therapeutic successes. Some journals have discontinued the case reports, while new case report journals have appeared in recent years. During the eightieth anniversary of Mycopathologia, it is fitting to examine the relevance of the case report since the journal continues to traverse the boundaries of basic and clinical sciences. A random sample of recent case reports and other articles were selected from Mycopathologia. Springer Nature individual article download statistics, and Google Scholar and Scopus citations numbers were compared to assess the reader access and bibliometric impact of case reports. Our analysis indicated that the case report format continues to be a vital element of publication in a cross-disciplinary journal such as Mycopathologia. Medical and veterinary case reports covering fungal pathogens are widely read as evident from their download numbers. The download numbers have a positive correlation with the completeness of the report, the topics and geographic origin of reports have a neutral influence, and the recency leads to lower downloads. There is no discernible trend between the download numbers and the citations of case reports as measured by Google Scholar and Scopus. A specially designed checklist for Mycopathologia case reports and new format MycopathologiaIMAGES are being introduced to improve the quality and relevance of case reports further.