COVID-19 associated mucormycosis (CAM) in Kashan, Iran: clinical presentations, risk factors, management, and outcomes

BACKGROUND

This study aimed to estimate the disease burden and describe the clinical presentation, risk factors, and outcome of CAM in a single centre in Iran.

METHODS

A case of mucormycosis was defined as one that had clinical and radiological features consistent with mucormycosis along with demonstration of the fungus in tissue via KOH mount/culture/histopathological and molecular examination.

RESULTS

We report 30 cases of COVID-19 associated mucormycosis (CAM). The results of this study showed the affected age group in the range of 40-79 years (median = 65.5; IQR = 5) with women (16/30, 53%) affected more than men (14/30, 47%). Among the fungi recovered, Rhizopus oryzae had the highest frequency (79%). Out of the 30 patients, 28 (93%) patients were diabetic with 24 (80%) patients having other co-morbidities. Headache followed by retro-orbital pain, proptosis/ptosis and rapid diminution of vision was a common sequence of symptoms reported by the majority of cases. Use of mechanical ventilation (58% vs. 6%, p = 0.003), O2 required (92% vs. 50%, p = 0.024), and development of renal dysfunction during hospital stay (17% vs. 0%, p = 0.041) was significantly higher in non-survivors than survivors. Temperature (C°), PR (pulse rate), mean levels of serum creatinine, BUN, troponin, and neutrophils were significantly higher in non-survivors (p < 0.05). Besides, Albumin and PO2 were also significantly higher in survivors than non-survivors.

CONCLUSION

Despite medical and surgical treatment, the mortality rate among CAM patients is still high. Thus, concerted efforts of revamping surveillance, diagnosis and management, along with public awareness and patient education, are the requisites for managing COVID-19 and mucormycosis.

Invasive Fusarium rhinosinusitis in COVID-19 patients: report of three cases with successful management

Invasive fungal rhinosinusitis (IFRS) is a life-threatening infection that can occur in immunocompromised patients, including those with COVID-19. Although Mucorales and Aspergillus species are the most common causes of IFRS, infections caused by other fungi such as Fusarium are rare. In this report, we present three cases of proven rhinosinusitis fusariosis that occurred during or after COVID-19 infection. The diagnosis was confirmed through microscopy, pathology, and culture, and species identification of the isolates was performed by DNA sequencing the entire ITS1-5.8 rRNA-ITS2 region and translation elongation factor 1-alpha (TEF-1α). Antifungal susceptibility testing was conducted according to CLSI guidelines. The causative agents were identified as Fusarium proliferatum, F. oxysporum + Aspergillus flavus, and F. solani/falciforme. Treatment involved the administration of antifungal medication and endoscopic sinus surgery to remove the affected mucosa, leading to the successful resolution of the infections. However, one patient experienced a recurrence of IFRS caused by A. flavus 15 months later. Early diagnosis and timely medical and surgical treatment are crucial in reducing mortality rates associated with invasive fusariosis. Additionally, the cautious use of corticosteroids in COVID-19 patients is highly recommended.

Diagnosis of mucormycosis using a simple duplex PCR assay: Analysis of 160 clinical samples from COVID-19 patients

Early diagnosis of mucormycosis, a severe and potentially fatal complication in immunocompromised and COVID-19 patients, is crucial for initiating timely antifungal therapy and reducing infection mortality. In this study, the diagnostic performance of a duplex polymerase chain reaction (PCR) assay was evaluated to detect Mucorales-specific and Rhizopus oryzae-specific targets in 160 clinical samples collected from 112 COVID-19 patients suspected of invasive fungal rhinosinusitis (IFRS). During potassium hydroxide (KOH) direct microscopy, non-septate hyphae were observed in 73 out of 160 samples (45.63%); however, using duplex PCR, 82 out of 160 specimens (51.25%) tested positive. Among the positive PCR samples, 67 (81.71%) exhibited a double band (both 175 and 450 base pairs [bp]) indicating the presence of R. oryzae, and 15 (18.29%) showed only a single band (175 bp), suggesting the presence of non-R. oryzae Mucorales. DNAs from 10 microscopically negative samples and 4 samples with septate hyphae in microscopy were successfully amplified in PCR. Considering Calcofluor white fluorescence microscopy as the gold standard for laboratory diagnosis of mucormycosis, the duplex PCR assay utilized in this study exhibited a sensitivity of 93.88%, a specificity of 100%, a negative predictive value of 91.18%, and a positive predictive value of 100% for detecting mucormycosis in IFRS specimens. The duplex PCR assay demonstrated higher sensitivity compared to direct examination with KOH (82 vs. 73) and culture (82 vs. 41), enabling rapid detection/identification of Mucorales even in samples with negative culture or in biopsies with only a few hyphal elements.

A case of COVID-19-associated mucormycosis due to Lichtheimia ramosa

BACKGROUND

Mucormycosis is a life-threatening invasive fungal infection in immunocompromised and COVID-19 patients.

CASE REPORT

Here, we report a fatal rhino-orbito-cerebral mucormycosis caused by Lichtheimia ramosa, in a 79-year-old diabetic female. She was initially admitted to the hospital for COVID-19 infection and received broad-spectrum antibiotics and corticosteroids. After 1 month, she was admitted again because of persistent headaches and decreased right eye movement when the computed tomography scan showed mucosal thickening and opacification of paranasal sinuses. Microbiological investigations, including culture and direct microscopy, and histopathological findings confirmed the diagnosis of proven mucormycosis. The isolated causal agent was identified as Lichtheimia ramosa by sequencing the entire ITS region of nuclear ribosomal DNA. Despite surgical debridement and administration of liposomal amphotericin B 5 mg/kg/day, the patient's level of consciousness suddenly deteriorated; she was intubated and mechanically ventilated in the ICU and died on the same day.

CONCLUSION

To our knowledge, this is the first worldwide case of COVID-19-associated rhino-orbito-cerebral mucormycosis due to Lichtheimia ramosa.

Case report: COVID-19-associated mucormycosis co-infection with Lomentospora prolificans: The first case and review on multiple fungal co-infections during COVID-19 pandemic

Along with the pandemic COVID-19 spreads, new clinical challenges have emerged in the health care settings, among which there is a high risk of secondary invasive fungal infections with significant mortality. Here, we report a case of invasive fungal rhino orbital sinusitis due to the simultaneous co-infection by Rhizopus oryzae and Lomentospora prolificans, both identified by sequencing, in a 70-year-old Afghanistanian female with COVID-19. The patient was subjected to surgical debridement as well as taking liposomal amphotericin B, voriconazole, and on discharge, her condition was good. As far as we know, this is the first case of co-infection of COVID-19-associated mucormycosis (CAM) and Lomentospora prolificans infection. Multiple fungal co-infections in COVID-19 patients are reviewed.

Microbial and clinical epidemiology of invasive fungal rhinosinusitis in hospitalized COVID-19 patients, the divergent causative agents

Since COVID-19 spread worldwide, invasive fungal rhinosinusitis (IFRS) has emerged in immunocompromised patients as a new clinical challenge. In this study, clinical specimens of 89 COVID-19 patients who presented clinical and radiological evidence suggestive of IFRS were examined by direct microscopy, histopathology, and culture, and the isolated colonies were identified through DNA sequence analysis. Fungal elements were microscopically observed in 84.27% of the patients. Males (53.9%) and patients over 40 (95.5%) were more commonly affected than others. Headache (94.4%) and retro-orbital pain (87.6%) were the most common symptoms, followed by ptosis/proptosis/eyelid swelling (52.8%), and 74 patients underwent surgery and debridement. The most common predisposing factors were steroid therapy (n = 83, 93.3%), diabetes mellitus (n = 63, 70.8%), and hypertension (n = 42, 47.2%). The culture was positive for 60.67% of the confirmed cases, and Mucorales were the most prevalent (48.14%) causative fungal agents. Different species of Aspergillus (29.63%) and Fusarium (3.7%) and a mix of two filamentous fungi (16.67%) were other causative agents. For 21 patients, no growth was seen in culture despite a positive result on microscopic examinations. In PCR-sequencing of 53 isolates, divergent fungal taxons, including 8 genera and 17 species, were identified as followed: Rhizopus oryzae (n = 22), Aspergillus flavus (n = 10), A. fumigatus (n = 4), A. niger (n = 3), R. microsporus (n = 2), Mucor circinelloides, Lichtheimia ramosa, Apophysomyces variabilis, A. tubingensis, A. alliaceus, A. nidulans, A. calidoustus, Fusarium fujikuroi/proliferatum, F. oxysporum, F. solani, Lomentospora prolificans, and Candida albicans (each n = 1). In conclusion, a diverse set of species involved in COVID-19-associated IFRS was observed in this study. Our data encourage specialist physicians to consider the possibility of involving various species in IFRS in immunocompromised and COVID-19 patients. In light of utilizing molecular identification approaches, the current knowledge of microbial epidemiology of invasive fungal infections, especially IFRS, may change dramatically.

A case of COVID-19-associated rhino-orbito-cerebral mucormycosis caused by Apophysomyces variabilis with a review of the literature

A fatal case of COVID-19-associated mucormycosis (CAM) affected a 40-year-old woman who was initially admitted to our hospital due to a SARS-CoV-2 infection. Her clinical condition worsened, and she finally died because of respiratory failure, hemodynamic instability, and mucormycosis with invasion into the orbit and probably the brain. According to DNA sequence analysis of the fungus isolated from the patient, Apophysomyces variabilis was involved. This is the first published case of CAM and the third case of mucormycosis due to this mold.