Mucormycosis in a Non-Hodgkin Lymphoma Patient Caused by Syncephalastrum racemosum: Case Report and Review of Literature

Disseminated Invasive Mucormycosis Infection Following Autologous Stem Cell Transplantation for Diffuse Large B-Cell Lymphoma

Invasive fungal infections (IFI) are challenging to predict, diagnose and treat, and are associated with a particularly high mortality among patients with hematological malignancies. They are relatively uncommon in patients with lymphoma, compared with those with acute leukemia or undergoing allogeneic transplantation. We present a patient, autografted for recurrent lymphoma, with fever and refractory diarrhea persisting post engraftment, eventually attributable to disseminated mucor infection. This case illustrates the challenge of timely diagnosis and initiation of treatment for IFI in lymphoma patients, who do not routinely receive antifungal prophylaxis, and the importance of aggressive investigation and symptom-directed tissue sampling for evidence of IFI in febrile immunocompromised hosts not responding to broad-spectrum antibiotics.

Rhino-Orbital-Cerebral Mycosis and Extranodal Natural Killer or/and T-Cell Lymphoma, Nasal Type

Background

Extranodal natural killer/T-cell lymphoma, nasal type is a syndrome of middle face destruction with an association to Epstein-Barr virus. Fungi have been recovered from the diseased tissue now and then but were often seen as a lymphoma-associated secondary infection. However, there are ENKTL-NT cases with the recoveries of fungi and complete recovery with antifungal therapy, which are quite similar to rhino-orbital-cerebral mycosis (ROCM) that often confuses the physicians.

Methods

We searched Medline for English-language manuscripts limited to “human” and “case reports,” “letters,” “reviews,” and “clinical conferences” from 1966 to 2022. We used MeSH terms “lymphoma, extranodal nk-t-cell” [MeSH Terms] or “lethal midline granuloma” [MeSH Terms], in combination with MeSH terms “microbiology” [subheading] or “microbiology” [all fields] or “fungi” [all fields] or “fungi” [MeSH Terms] for ENKTL-NT with infections. We used MeSH terms “Mycoses” in combination with “Nose” [Mesh] OR “Orbital Diseases” [Mesh] for rhino-orbital-cerebral fungal infections.

Results

We appraised 149 included articles and extracted references related to ENKTL-NT and/or ROCM. Themes and subcategories were subsequently derived. Our findings revealed that ROCM and ENKTL-NT are characterized by progressive and destructive ulcers in the midline face or rhino-orbital structures. ROCM is mainly caused by fungi in the order of Mucorales, and ENKTL-NT is usually associated with Epstein-Barr virus and sometimes fungi. Radiologically, both are characterized by non-specific features of sinusitis, soft tissue infection, and necrosis. Pathologically, ROCM and ENKTL-NT share the same characteristics of inflammation, necrosis, and granuloma. ROCM is characterized by the detection of fungi in tissue, while ENKTL-NT is typically positive for NK/T-cell markers and cytotoxic granule-associated proteins, proliferation, and vascular damage of angioinvasion, which could be incited by Mucor irregularis and Rhizopus arrhizus in patients and mice.

Conclusion

ENKTL-NT and ROCM share many similarities in clinical presentations, radiology, and histopathology, and might have the same etiology. This may explain why the two diseases are tangled together in the reported cases, and suggests the role that the fungi may play in the development of these ENKTL-NT/ROCM diseases. The reason why ENKTL-NT and ROCM are sometimes confused is that the main pathogens of ROCM, Mucor irregularis and Rhizopus arrhizus, are the fungal causative agents of ENKTL-NT.

Invasive pulmonary infection by Syncephalastrum species: Two case reports and review of literature

Background

Syncephalastrum species belong to the class Zygomycetes and order Mucorale. These are found in the environment and tropical soil, usually presenting as colonizers and rarely cause human infection. Syncephalastrum racemosum is a species of the genus Syncephalastrum and is the most commonly identified pathogen. Most cases are reported in immunocompromised individuals, such as patients on long term steroids, poorly controlled diabetes, or patients with malignancy.

Case presentation

We are describing two cases of rare fungal infection by Syncephalastrum species causing invasive pulmonary manifestation. Both patients had compromised immune status and presented with worsening dyspnea to the emergency room. Both had signs and symptoms of bilateral worsening pneumonia evident by chest X-ray showing bilateral pulmonary infiltrates. Syncephalastrum species were isolated from sputum cultures. Deoxycholate amphotericin B was started and the response was monitored. One patient expired while the other improved. Syncephalastrum species belong to class Mucormycosis, rarely causing invasive infection but when they do outcome is potentially fatal. Very few cases are reported worldwide so the clinical course is still unclear. To the best of our knowledge, these are the first two cases to be reported from Pakistan.

Conclusions

These two cases describe pneumonia as a result of concomitant infection by rare fungal speciesSyncephalastrum and MRSA in immunocompromised patients. Few cases are reported so limited data is available to understand complete disease implications. Mucormycosis is a therapeutic challenge because of the phylogenetic diversity, un-availability of any serological testing and invasive disease pattern.

Gastrointestinal involvement of unusual Mucormycete Syncephalastrum racemosum in a diabetic patient with adenocarcinoma: rare case presentation with review of literature

BACKGROUND

Mucormycosis is a serious and often fatal mycotic infection caused by members of class Mucormycetes in populations with immunologic or metabolic disorders. Though several clinical manifestations are associated with mucormycetes, gastrointestinal involvement is quite rare.

CASE DESCRIPTION

We described a rare case of invasive fungal infection due to Syncephalastrum racemosum associated with gastric adenocarcinoma in a 48-year-old male patient with type II Diabetes mellitus. He presented with complaints of abdominal pain, nausea, vomiting, dyspepsia, dysphagia, loss of appetite, and weight. Histopathological examination showed broad and aseptate hyphae and culture of endoscopic biopsy tissue from pylorus and antrum yielded the fungal pathogen S. racemosum. The species was confirmed by molecular sequencing of D1/D2 region of the ribosomal DNA. The in vitro susceptibility of S. racemosum was tested by broth microdilution assay as per CLSI guidelines. The MICs suggest that the isolate was susceptible to Amphotericin B (0.25 µg/ml), Itraconazole (0.25 µg/ml) and Posaconazole (0.06 µg/ml) and showed resistance to Micafungin (>16 µg/ml). The patient was successfully treated with radical subtotal gastrectomy with lymphadenectomy and Amphotericin B antifungal therapy. There was a dilemma in concluding the pathogenicity of the isolate since; the symptoms noted were common for both gastric adenocarcinoma and mucormycosis. A review of previously reported cases on Syncephalastrum was presented in the paper with their clinical manifestations, treatment, and outcome.

CONCLUSION

To the best of our knowledge, this is the first report from India on the gastrointestinal involvement of S. racemosum. Patients with immunocompromised status are more prone to mucormycotic infections, and any typical presentations should be carefully examined for their etiological agent, and appropriate species directed therapy would help in a better outcome.

Diabetes mellitus as the major risk factor for mucormycosis in Mexico: Epidemiology, diagnosis, and outcomes of reported cases

Mucormycosis is an emerging infectious disease with high rates of associated mortality and morbidity. Little is known about the characteristics of mucormycosis or entomophthoromycosis occurring in Mexico. A search strategy was performed of literature published in journals found in available databases and theses published online at Universidad Nacional Autónoma de México (UNAM) library website reporting clinical cases or clinical case series of mucormycosis and entomophthoromycosis occurring in Mexico between 1982 and 2016. Among the 418 cases identified, 72% were diabetic patients, and sinusitis accounted for 75% of the reported cases. Diabetes mellitus was not a risk factor for entomophthoromycosis. Mortality rate was 51% (125/244). Rhizopus species were the most frequent isolates (59%, 148/250). Amphotericin B deoxycholate was used in 89% of cases (204/227), while surgery and antifungal management as combined treatment was used in 90% (172/191). In diabetic individuals, this combined treatment approach was associated with a higher probability of survival (95% vs 66%, OR = 0.1, 95% CI, 0.02-0.43' P = .002). The most common complications were associated with nephrotoxicity and prolonged hospitalization due to IV antifungal therapy. An algorithm is proposed to establish an early diagnosis of rhino-orbital cerebral (ROC) mucormycosis based on standardized identification of warning signs and symptoms and performing an early direct microbiological exam and histopathological identification through a multidisciplinary medical and surgical team. In summary, diabetes mellitus was the most common risk factor for mucormycosis in Mexico; combined antifungal therapy and surgery in ROC mucormycosis significantly improved survival.

Distinct Microbial Signatures Associated With Different Breast Cancer Types

A dysbiotic microbiome can potentially contribute to the pathogenesis of many different diseases including cancer. Breast cancer is the second leading cause of cancer death in women. Thus, we investigated the diversity of the microbiome in the four major types of breast cancer: endocrine receptor (ER) positive, triple positive, Her2 positive and triple negative breast cancers. Using a whole genome and transcriptome amplification and a pan-pathogen microarray (PathoChip) strategy, we detected unique and common viral, bacterial, fungal and parasitic signatures for each of the breast cancer types. These were validated by PCR and Sanger sequencing. Hierarchical cluster analysis of the breast cancer samples, based on their detected microbial signatures, showed distinct patterns for the triple negative and triple positive samples, while the ER positive and Her2 positive samples shared similar microbial signatures. These signatures, unique or common to the different breast cancer types, provide a new line of investigation to gain further insights into prognosis, treatment strategies and clinical outcome, as well as better understanding of the role of the micro-organisms in the development and progression of breast cancer.

Synthesis and Antifungal Screening of 2-{[1-(5-Alkyl/arylalkylpyrazin-2-yl)ethylidene]hydrazono}-1,3-thiazolidin-4-ones

Two novel thiosemicarbazones and eight novel 2-{[1-(5-alkyl/arylalkylpyrazin-2-yl)ethylidene]hydrazono}-1,3-thiazolidin-4-ones were prepared and tested against a panel of eight fungal strains–Candida albicans ATCC 44859, Candida tropicalis 156, Candida krusei E 28, Candida glabrata 20/I, Trichosporon asahii 1188, Aspergillus fumigatus 231, Lichtheimia corymbifera 272, and Trichophyton interdigitale 445. 1,3-Thiazolidin-4-ones exhibited activity against all strains, the most potent derivative was 2-{[1-(5-butylpyrazin-2-yl)ethylidene]hydrazono}e-1,3-thiazolidin-4-one. Susceptibility of C. glabrata to the studied 1,3-thiazolidin-4-ones (minimum inhibitory concentrations (MICs) were in the range 0.57 to 2.78 mg/L) is of great interest as this opportunistic pathogen is poorly susceptible to azoles and becomes resistant to echinocandins. Antifungal potency of thiosemicarbazones was slightly lower than that of 1,3-thiazolidin-4-ones.

Emerging infections caused by non-Aspergillus filamentous fungi

There are three broad groups of non-Aspergillus moulds: the mucormycetes, the hyalohyphomycetes and the phaeohyphomycetes. Infections with these pathogens are increasingly reported, particularly in the context of increasing use of immunosuppressant agents and improved diagnostics. The epidemiology of non-Aspergillus mould infections varies with geography, climate and level of immunosuppression. Skin and soft-tissue infections are the predominant presentation in the immunocompetent host and pulmonary and other invasive infections in the immunocompromised host. The more common non-Aspergillus moulds include Rhizopus, Mucor, Fusarium and Scedosporium species; however, other emerging pathogens are Rasamsonia and Verruconis species, which are discussed in this article. Outbreaks of non-Aspergillus mould infections have been increasingly reported, with contaminated medical supplies and natural disasters as common sources. Currently culture and other conventional diagnostic methods are the cornerstone of diagnosis. Molecular methods to directly detect and identify mould pathogens in tissue and body fluids are increasingly used.