Comparison of Clinical Manifestation, Diagnosis, and Outcomes of Invasive Pulmonary Aspergillosis and Pulmonary Mucormycosis

Pulmonary Mucormycosis Involving the Left Main Bronchus and the Pulmonary Artery

Pulmonary mucormycosis is an extremely rare disease. It often occurs in immunocompromised patients, such as patients with diabetes and those on long-term steroid use. The prognosis of the disease is poor despite the administration of antifungal agents and removal of the necrotic tissue. Herein, we present a successfully treated case of pulmonary mucormycosis in a patient with type 2 diabetes who underwent left pneumonectomy because of the involvement of the left main pulmonary artery and the left main bronchus. Irrespective of the infected organ, complete debridement of the infected tissue and treatment with antifungal agents are essential for treating mucormycosis.

Disease burden and demographic characteristics of mucormycosis: A nationwide population-based study in Taiwan, 2006-2017

BACKGROUND

Epidemiological knowledge of mucormycosis obtained from national population-based databases is scarce.

OBJECTIVES

This study aimed to depict the disease burden and demographics of mucormycosis in Taiwan by using the Taiwan National Health Insurance Research Database (NHIRD) and those of aspergillosis as a comparator.

METHODS

Data from patients with either mucormycosis or aspergillosis from 2006 to 2017 identified with the International Classification of Diseases (ICD) codes were extracted from the NHIRD. The incidence, demographics and clinical data of both diseases were analysed.

RESULTS

A total of 204 patients with mucormycosis and 2270 patients with aspergillosis who were hospitalised and treated with mould-active antifungals between 2006 and 2017 were identified. The average annual incidence of aspergillosis (0.81 cases per 100,000 population [0.81/100,000]) was 11-fold higher than that of mucormycosis (0.07/100,000). A significant increase in incidence was observed for aspergillosis (from 0.48/100,000 in 2006 to 1.19/100,000 in 2017, p < .0001) but not for mucormycosis (from 0.04/100,000 in 2006 to 0.11/100,000 in 2017, p = .07). The major underlying disease identified was diabetes mellitus (60.8%) for mucormycosis and malignant neoplasms (45.9%) for aspergillosis. The all-cause 90-day mortality rate was similar between mucormycosis and aspergillosis patients (39% vs. 37%, p = .60). For mucormycosis patients, multivariate analysis revealed that posaconazole use was associated with lower in-hospital mortality (aOR 0.38; 95% CI 0.15-0.97; p = .04).

CONCLUSIONS

Mucormycosis is an uncommon fungal disease in Taiwan, occurring mostly in diabetic patients. However, the incidence might be underestimated due to limited diagnostics. Continuous surveillance might aid in delineating the evolving features of mucormycosis.

Definition, diagnosis, and management of COVID-19-associated pulmonary mucormycosis: Delphi consensus statement from the Fungal Infection Study Forum and Academy of Pulmonary Sciences, India

COVID-19-associated pulmonary mucormycosis (CAPM) remains an underdiagnosed entity. Using a modified Delphi method, we have formulated a consensus statement for the diagnosis and management of CAPM. We selected 26 experts from various disciplines who are involved in managing CAPM. Three rounds of the Delphi process were held to reach consensus (≥70% agreement or disagreement) or dissensus. A consensus was achieved for 84 of the 89 statements. Pulmonary mucormycosis occurring within 3 months of COVID-19 diagnosis was labelled CAPM and classified further as proven, probable, and possible. We recommend flexible bronchoscopy to enable early diagnosis. The experts proposed definitions to categorise dual infections with aspergillosis and mucormycosis in patients with COVID-19. We recommend liposomal amphotericin B (5 mg/kg per day) and early surgery as central to the management of mucormycosis in patients with COVID-19. We recommend response assessment at 4–6 weeks using clinical and imaging parameters. Posaconazole or isavuconazole was recommended as maintenance therapy following initial response, but no consensus was reached for the duration of treatment. In patients with stable or progressive disease, the experts recommended salvage therapy with posaconazole or isavuconazole. CAPM is a rare but under-reported complication of COVID-19. Although we have proposed recommendations for defining, diagnosing, and managing CAPM, more extensive research is required.

Exploring the Clinical Utility of Metagenomic Next-Generation Sequencing in the Diagnosis of Pulmonary Infection

INTRODUCTION

We aimed to explore the real-world clinical application value and challenges of metagenomic next-generation sequencing (mNGS) for pulmonary infection diagnosis.

METHODS

We retrospectively reviewed the results of mNGS and conventional tests from 140 hospitalized patients with suspected pulmonary infections from January 2019 to December 2020. The sample types included bronchoalveolar lavage fluid, lung tissue by transbronchial lung biopsy, pleural effusion, blood, and bronchial sputum. Apart from the mNGS reports that our patients received, an extra comprehensive and thorough literature search was conducted.

RESULTS

Significant differences were noticed in the positive detection rates of pathogens between mNGS and conventional diagnostic testing (115/140, 82.14% vs 50/140, 35.71%, P < 0.05). The percentage of mNGS-positive patients was significantly higher than that of conventional testing-positive patients with regard to bacterial detection (P < 0.01), but no significant differences were found with regard to fungal detection (P = 0.67). Significant statistical differences were found between mixed infection cases (15, 22.70%) and single infection cases (4, 7.84%) in terms of diabetes (P = 0.03). The most frequent pattern of mixed infection was bacteria and fungi mixed infection (40, 40/89 = 44.94%), followed by bacteria mixed infection (29, 29/89 = 32.58%). The sensitivity of mNGS in pulmonary infection diagnosis was much higher than that of conventional test (89.17% vs 50.00%; P < 0.01), but the specificity was the opposite (75.00% vs 81.82%; P > 0.05).

CONCLUSION

mNGS is a valuable tool for the detection of pulmonary infections, especially mixed pulmonary infections. The most common combinations we found were bacterial-fungal coinfection and bacterial-bacterial coinfection. Still, there are many challenges in the clinical application of mNGS in the diagnosis of pulmonary infections. There is still a lot of work to be done in interpreting the mNGS reports, because both clinical judgment and literature analysis strategy need to be refined.

Role of flexible bronchoscopy in the diagnosis of invasive fungal infections

BACKGROUND

There are sparse data on the role of flexible bronchoscopy (FB) in diagnosing invasive mould infections (IMIs).

OBJECTIVE

To investigate the safety and usefulness of FB in IMI. We evaluate the factors associated with a successful diagnosis of IMI using FB. Further, we compare subjects of invasive pulmonary aspergillosis (IPA) with pulmonary mucormycosis (PM).

METHODS

We retrospectively reviewed the clinical features, imaging data, bronchoscopy, microbiology and pathology details of subjects who underwent FB for suspected IMI. We categorised FB as diagnostic if it contributed to the diagnosis of IMI. We performed a multivariate analysis to identify the factors associated with a diagnostic bronchoscopy.

RESULTS

Of the 3521 FB performed over 18 months, 132 (3.7%) were done for suspected IMIs. We included 107 subjects for the final analysis. The risk factors for IMI included renal transplantation (29.0%), diabetes (27.1%), haematological malignancy (10.3%) and others. We found bronchoscopic abnormalities in 33 (30.8%) subjects, and these were more frequent in those with confirmed PM (67%) than IPA (27%). IMI was confirmed in 79 (14 proven, 48 probable and 17 possible) subjects. FB was diagnostic in 71%. We experienced major complications in three cases (2.7%), including one death. On multivariate analysis, the visualisation of endobronchial abnormalities during FB (OR [95%, CI], 8.5 [1.4-50.4]) was the only factor associated with a diagnostic FB after adjusting for age and various risk factors.

CONCLUSIONS

Flexible bronchoscopy is a useful and safe procedure in diagnosing IMIs. The presence of endobronchial abnormalities predicts a successful diagnostic yield on FB.

The disease burden of mucormycosis in Japan: results from a systematic literature review and retrospective database study

OBJECTIVE

To evaluate outcomes, healthcare resource utilization, and costs associated with mucormycosis in inpatient settings in Japan.

METHODS

We performed a systematic literature review, followed by a retrospective database study using hospital health claims for patients in Japan hospitalized with a diagnosis of mucormycosis between January 2010 and January 2019. Outcomes assessed included duration of index hospitalization; index stay mortality; hospital readmission within 30, 60, and 90 days after index hospitalization discharge; drug/treatment utilization and patterns; number of patients examined for mucormycosis during the index hospitalization; and index stay inpatient costs.

RESULTS

From our systematic literature review of articles describing 133 patients with mucormycosis, mortality in the index hospitalization was 55.6%. From our database study of 126 patients hospitalized for mucormycosis, mortality during the index hospitalization was 35.7% and mean index stay duration was 94 days. Hematologic malignancies were the most common risk factor in the literature review and the most common comorbidity in the database study. During the index stay, 39 patients (31.0%) received liposomal amphotericin B (L-AMB) treatment and 74 patients (58.7%) received other antifungal treatments. Median total inpatient costs for the index hospitalization were equivalent to approximately US$60,945, including US$29,283 in drug costs.

CONCLUSIONS

This study investigated the healthcare resource utilization and cost of medical resources caused by mucormycosis in Japan. The drug costs for antifungal treatments comprised about half of total inpatient costs. Mucormycosis leads to high mortality, high healthcare resource utilization, and high costs.

Has the mortality from pulmonary mucormycosis changed over time? A systematic review and meta-analysis

OBJECTIVES

Pulmonary mucormycosis (PM) is increasingly being reported in immunocompromised patients and has a high mortality. Our aim was to assess the mortality of PM and its trend over time. We also evaluated the role of combined medical-surgical therapy in PM.

METHODS

We performed a systematic review of Pubmed, Embase, and Cochrane central databases. Studies were eligible if they described at least five confirmed cases of PM and reported mortality. We also assessed the effect of combined medical-surgical therapy versus medical treatment alone on PM mortality. We used a random-effects model to estimate the pooled mortality of PM and compared it across three time periods. The factors influencing mortality were assessed using meta-regression. We evaluated the risk difference (RD) of death in the following: subjects undergoing combined medical-surgical therapy versus medical therapy alone, subjects with isolated PM versus disseminated disease, and PM in diabetes mellitus (DM) versus non-DM as a risk factor.

RESULTS

We included 79 studies (1544 subjects). The pooled mortality of PM was 57.1% (95% confidence interval [CI] 51.7-62.6%). Mortality improved significantly over time (72.1% versus 58.3% versus 49.8% for studies before 2000, 2000-2009, and 2010-2020, respectively, p 0.00001). This improved survival was confirmed in meta-regression after adjusting for the study design, the country's income level, and the sample size. Combined medical-surgical therapy was associated with a significantly lower RD (95%CI) of death: -0.32 (-0.49 to -0.16). The disseminated disease had a higher risk of death than isolated PM, but DM was not associated with a higher risk of death than other risk factors.

CONCLUSIONS

While PM is still associated with high mortality, we noted improved survival over time. Combined medical-surgical therapy improved survival compared to medical treatment alone.

Diagnostic value of galactomannan in serum and bronchoalveolar lavage fluid for invasive pulmonary aspergillosis in non-neutropenic patients

OBJECTIVE

To evaluate the diagnostic performance of galactomannan (GM) detection in serum and bronchoalveolar lavage fluid (BALF) for invasive pulmonary aspergillosis (IPA) in non-neutropenic patients.

METHODS

A total of 291 non-neutropenic patients in the Second Xiangya Hospital of Central South University were included. According to the 2019 EORTC/MSG guidelines, all cases were divided into an IPA group (n = 24) and a non-IPA group (n = 267). Receiver operating characteristic (ROC) curves were drawn to compare the diagnostic efficiency of GM detection in BALF and serum.

RESULTS

According to the receiver operating characteristic curves of BALF and serum GM, the areas under the curve were 0.961 and 0.699, respectively. The optimal BALF GM detection was found when the cutoff value was set to 0.87, whereas the sensitivity and specificity were 91.7% and 92.5%, respectively.

CONCLUSIONS

BALF GM detection is more sensitive than serum GM detection for diagnosing IPA, and the optimal cutoff value for BALF GM is 0.87.

Latest Thoughts on Treating Pediatric Mucormycosis

Mucormycosis is one of the most complicated to diagnose and treat invasive fungal diseases. Diagnostic techniques have not significantly advanced in years, and recent international consensus treatment guidelines offer some insight into the current best approaches to treating this deadly invasive mold.

Digestive enzymes of fungal origin as a relevant cause of false positive Aspergillus antigen testing in intensive care unit patients

Background

Galactomannan antigen (GM) testing is widely used in the diagnosis of invasive aspergillosis (IA). Digestive enzymes play an important role in enzyme substitution therapy in exocrine pancreatic insufficiency. As digestive enzymes of fungal origin like Nortase contain enzymes from Aspergillus, a false-positive result of the test might be possible because of cross-reacting antigens of the cell wall of the producing fungi. We, therefore, asked whether the administration of fungal enzymes is a relevant cause of false-positive GM antigen test results.

Methods

Patients with a positive GM antigen test between January 2016 and April 2020 were included in the evaluation and divided into two groups: group 1—Nortase-therapy, group 2—no Nortase-therapy. In addition, dissolved Nortase samples were analyzed in vitro for GM and β-1,3-D-glucan. For statistical analysis, the chi-squared and Mann‒Whitney U tests were used.

Results

Sixty-five patients were included in this evaluation (30 patients receiving Nortase and 35 patients not receiving Nortase). The overall false positivity rate of GM testing was 43.1%. Notably, false-positive results were detected significantly more often in the Nortase group (73.3%) than in the control group (17.1%, p < 0.001). While the positive predictive value of GM testing was 0.83 in the control group, there was a dramatic decline to 0.27 in the Nortase group. In vitro analysis proved that the Nortase enzyme preparation was highly positive for the fungal antigens GM and β-1,3-D-glucan.

Conclusions

Our data demonstrate that the administration of digestive enzymes of fungal origin like Nortase leads to a significantly higher rate of false-positive GM test results compared to that in patients without digestive enzyme treatment.

A case of invasive pulmonary mucormycosis resulting from short courses of corticosteroids in a well-controlled diabetic patient

A patient with well-controlled type 2 diabetes mellitus developed a severe pulmonary infection secondary to Rhizopus spp. after receiving short courses of corticosteroids for a respiratory tract infection. He recovered after an aggressive surgical intervention and treatment with isavuconazole. Patients on chronic corticosteroid therapy have a higher risk for pulmonary mucormycosis, but there are much fewer reports of mucormycosis occurring in patients after only short courses of steroid therapy.

Risk factors for mortality in patients with pulmonary mucormycosis

BACKGROUND

Pulmonary mucormycosis (PM) represents a serious burden in terms of morbidity and mortality in immunocompromised patients. Studies of prognostic factors in patients with PM are limited and have involved small numbers of patients.

METHODS

Adult patients diagnosed with proven and probable PM according to the modified definitions of the EORTC/MSG 2008 in a tertiary hospital in Seoul, South Korea, between 2008 and 2019 were retrospectively enrolled.

RESULTS

A total of 49 patients including 31 (63%) with proven PM and 18 (37%) with probable PM were enrolled. The 90-day mortality rate was 49% (24/49). Neutropenia, thrombocytopenia, use of voriconazole at clinical suspicion, positivity of non-sterile culture, use of steroid and treatment without surgery were more common in fatal cases than non-fatal cases. Voriconazole use at clinical suspicion for invasive mould pneumonia (OR 6.91, P = .01) and prolonged neutropenia (OR 4.86, P = .03) were independent risk factors for mortality. Voriconazole use at clinical suspicion was associated with positive galactomannan (GM) assay (OR 5.93, P = .02) and history of invasive pulmonary aspergillosis (OR, 6.88, P = .05).

CONCLUSION

About half of the patients with PM died within 90 days of diagnosis, and fatal outcomes were common in patients with prolonged neutropenia and empirical voriconazole use. Caution is needed in using voriconazole even in patients with positive GM results and prior histories of invasive pulmonary aspergillosis in whom PM cannot be ruled out by differential diagnosis.