Necrotizing pneumonia due to Aspergillus and Salmonella after immune checkpoint inhibitor treatment: An unusual case and review of the literature

BACKGROUND

Immune checkpoint inhibitors (ICIs) are a promising new treatment for different types of cancer. The infectious complications in patients taking ICIs are rare.

CASE REPORT

A 58-year-old male who received chemotherapy consisting of pembrolizumab (PD-1 inhibitor) for esophagus squamous cell carcinoma one month before was admitted to the emergency room with shortness of breath soon after fiberoptic bronchoscopy, which was done for the inspection of the lower airway. A computed tomography of the chest revealed a progressive consolidation on the right upper lobe. Salmonella group D was isolated from the bronchoalveolar lavage (BAL) fluid culture. The fungal culture of the same clinical sample yielded Aspergillus niger; furthermore, a high titer (above the cut-off values) of Aspergillus antigen was found both in the BAL fluid and serum of the patient. Despite the effective spectrum and appropriate dose of antimicrobial treatment, the patient died due to disseminated intravascular coagulopathy.

CONCLUSIONS

Awareness of unusual pathogens in the etiology of pneumonia after ICI treatment may help to avoid underdiagnosis.

Evaluation of the diagnostic accuracy of galactomannan from the bronchoalveolar lavage fluid of patients with suspected invasive pulmonary aspergillosis

BACKGROUND

Several studies to evaluate the accuracy of galactomannan (GM) in bronchoalveolar lavage fluid (BALF) as a diagnostic tool have been carried out; however, there are still controversies about the optimal cut-off point of BALF GM.

AIMS

The objective of this study was to determine the diagnostic accuracy and the optimal cut-off point on BALF GM from patients with suspected invasive pulmonary aspergillosis (IPA) in a tertiary care hospital.

METHODS

A cross-sectional study with 188 patients (≥18 years) that had undergone a bronchoscopy with BAL due to suspected IPA was carried out. IPA was diagnosed according to the EORTC/MSG guidelines.

RESULTS

The optimal optical density cut-off point for BALF GM was 0.67, with sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 70%, 32.3%, and 100%, respectively.

CONCLUSIONS

BALF GM detection proved to be a useful supplementary technique in the early diagnosis of IPA in both neutropenic and non-neutropenic patients.

Invasive pulmonary aspergillosis in patients with acute respiratory syndrome by COVID-19

Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of Galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1 mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.

[Individualized antifungal therapy in critically ill patients with invasive fungal infection]

Invasive candidiasis (IC) is the most common invasive fungal infection (IFI) affecting critically ill patients, followed by invasive pulmonary aspergillosis (IPA). International guidelines provide different recommendations for a first-line antifungal therapy and, in most of them, echinocandins are considered the first-line treatment for IC, and triazoles are so for the treatment of IPA. However, liposomal amphotericinB (L-AmB) is still considered a second-line therapy for both clinical entities. Although in the last decade the management of IFI has improved, several controversies persist. The antifungal drugs currently available may have a suboptimal activity, or be wrongly used in certain IFI involving critically ill patients. The aim of this review is to analyze when to provide individualized antifungal therapy to critically ill patients suffering from IFI, emphasizing the role of L-AmB. Drug-drug interactions, the clinical status, infectious foci (peritoneal candidiasis is discussed), the fungal species involved, and the need of monitoring the concentration of the antifungal drug in the patient are considered.

Invasive pulmonary aspergillosis in patients with acute respiratory syndrome by COVID-19

Patients with COVID-19 who are admitted to intensive care unit (ICU) are at high risk of developing secondary infections, including invasive fungal infections such as invasive pulmonary aspergillosis (IPA). The main purpose was to analyse the putative COVID-19 Associated Pulmonary Aspergillosis (CAPA) patients in our setting. In these patients, we performed mycological culture in bronchoalveolar lavage (BAL) for isolation of Aspergillus sp. We followed the AspICU algorithm to diagnose putative IPA. Moreover, we considered relevant the positivity of galactomannan in BAL. We diagnosed putative IPA in 3 patients. The common features of these 3 patients were: more than 21 days of stay in ICU, severe acute respiratory distress syndrome (ARDS) and treatment with steroids (1mg/kg per day). Therefore, CAPA has to be systematically considered although a new algorithm to diagnose it is needed to treat patients in early stages in order to avoid catastrophic outcomes.

[Invasive pulmonary aspergillosis in patients with chronic obstructive pulmonary disease]

Invasive pulmonary aspergillosis (IPA) is a common infection in immunocompromised patients with hematological malignancies or allogenic stem cell transplantation, and is less frequent in the context of chronic obstructive pulmonary disease (COPD). Mucociliary activity impairment, immunosuppression due to the inhibition of alveolar macrophages and neutrophils by steroids, and receiving broad-spectrum antibiotics, play a role in the development of IPA in COPD patients. Colonized patients or those with IPA are older, with severe CODP stage (GOLD≥III), and have a higher number of comorbidities. The mortality rate is high due to the fact that having a definitive diagnosis of IPA in COPD patients is often difficult. The main clinical and radiological signs of IPA in these types of patients are non-specific, and tissue samples for definitive diagnosis are often difficult to obtain. The poor prognosis of IPA in COPD patients could perhaps be improved by faster diagnosis and prompt initiation of antifungal treatment. Some tools, such as scales and algorithms based on risk factors of IPA, may be useful for its early diagnosis in these patients.

[The different manifestations of pulmonary aspergillosis: multidetector computed tomography findings]

Pulmonary aspergillosis is a fungal infection usually caused by inhaling Aspergillus fumigatus spores. However, when we talk about aspergillosis, we normally refer to the spectrum of clinical and radiological findings that depend directly on the patient's immune status, on the prior existence of lung disease, and on the virulence of the infective organism. There are four types of pulmonary aspergillosis (aspergilloma, allergic bronchopulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, and invasive aspergillosis), and each type has its own distinct radiologic findings. We review the signs of pulmonary aspergillosis on multidetector computed tomography and we correlate them with patients' symptoms and immune responses. Likewise, we discuss the differential diagnoses.