Pathologic manifestations of invasive pulmonary aspergillosis in cancer patients: the many faces of aspergillus

Concurrent aspergillosis and cystic pulmonary metastases in a patient with tongue squamous cell carcinoma

Pulmonary Aspergillus infection may have a variety of manifestations depending on the patients’ immunity status and pre-existing lung conditions. Radiographically, aspergilloma, which is usually associated with noninvasive Aspergillus fumigatus conidia, may feature a characteristic mass in a cavity commonly located in the upper lobes of the lung. It is typically encountered upon pre-existing lung damage. Here we report Aspergillus growing in a pulmonary metastatic cavity in a 47-year-old male worker with a history of tongue cancer after a radical operation with neck dissection and concurrent chemotherapy in 2014. Chest radiography and computed tomography showed a cavitary lesion with a ball-in-hole lesion in the right upper lobe (RUL) and two cystic lesions within the bilateral upper lung field. Endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) from the RUL anterior segmental bronchus (RB3) revealed the presence of Aspergillus conidia and squamous cell carcinoma. Wedge resection of the cystic lesion within the left upper lobe confirmed the diagnosis of metastatic squamous cell carcinoma. This is a rare case of aspergillosis within cavities of pulmonary metastases in a patient who was diagnosed with tongue squamous cell carcinoma. The conclusive distinction between neoplasm and fungal infection is difficult to achieve by radiography, and a pathological biopsy by EBUS-TBB is necessary to aid diagnosis. Clinicians should be aware of such an atypical presentation of metastases coexisting with Aspergillus infection.

Invasive pulmonary aspergillosis in a patient with cirrhosis

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Invasive pulmonary aspergillosis should be considered in critically ill patients without neutropenia or obvious systemic immunosuppression.

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Patients with cirrhosis have a weakened immune system and are at risk for invasive fungal diseases including pulmonary aspergillosis.

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Algorithms for diagnosing invasive fungal infections provide useful guidance but should not replace clinical suspicion.

Aspergillus molds are ubiquitous environmental molds that can cause devastating invasive infections in immunocompromised patients. These infections often go unrecognized in critically ill patients. This case describes a 68 year-old female resident of a long-term nursing facility with history of dementia, nonalcoholic fatty liver disease with cirrhosis, chronic kidney disease stage III and insulin-dependent type 2 diabetes who presented with vomiting, diarrhea and leg swelling. She developed hypotension and was treated for sepsis but found to have negative routine infectious workup. Chest imaging showed nodular densities and bilateral opacities. She developed acute renal failure and hypoxic respiratory failure followed by acute decompensated cirrhosis with refractory volume overload and hypotension and was eventually transitioned to comfort care measures. Autopsy ultimately showed invasive pulmonary aspergillosis. Here we review the diagnosis and management of invasive fungal infections in critically ill patients without typical risk factors or clinical findings for invasive fungal disease. Invasive fungal infections are frequently missed and carry high mortality rates, therefore warranting consideration in critically ill populations.

Fungal Thyroiditis: An Overview

The authors review the epidemiology, clinical manifestations, diagnosis, and treatment of fungal thyroiditis cases previously reported in the medical literature. Aspergillus was by far the most common cause of fungal thyroiditis. Immunocompromised patients, such as those with leukemia, lymphoma, autoimmune diseases, and organ-transplant patients on pharmacological immunosuppression were particularly at risk. Fungal thyroiditis was diagnosed at autopsy as part of disseminated infection in a substantial number of patients without clinical manifestations and laboratory evidence of thyroid dysfunction. Local signs and symptoms of infection were indistinguishable from other infectious thyroiditis and included fever, anterior cervical pain, thyroid enlargement sometimes associated with dysphagia and dysphonia, and clinical and laboratory features of transient hyperthyroidism due to the release of thyroid hormone from follicular cell damage, followed by residual hypothyroidism. Antemortem diagnosis of fungal thyroiditis was made by direct microscopy and culture of a fine-needle aspirate, or/and biopsy in most cases. Since most patients with fungal thyroiditis had disseminated fungal infection with delay in diagnosis and treatment, the overall mortality was high.

Immunity to Aspergillus fumigatus: the basis for immunotherapy and vaccination

Efficient responses to fungi require different mechanisms of immunity. Dendritic cells (DCs) are uniquely able to decode the fungus-associated information and translate it into qualitatively different T helper (Th) immune responses. Murine and human DCs phagocytose conidia and hyphae of Aspergillus fumigatus through distinct recognition receptors. The engagement of distinct receptors translates into disparate downstream signaling events, ultimately affecting cytokine production and co-stimulation. Adoptive transfer of different types of DCs activates protective and non-protective Th cells as well as regulatory T cells, ultimately affecting the outcome of the infection in mice with invasive aspergillosis. The infusion of fungus-pulsed or RNA-transfected DCs also accelerates recovery of functional antifungal Th 1 responses in mice with allogeneic hematopoietic stem cell transplantation. Patients receiving T cell-depleted allogeneic hematopoietic stem cell transplantation are unable to develop antigen-specific T cell responses soon after transplant due to defective DC functions. Our results suggest that the adoptive transfer of DCs may restore immunocompetence in hematopoietic stem cell transplantation by contributing to the educational program of T cells. Thus, the remarkable furictional plasticity of DCs can be exploited for the deliberate targeting of cells and pathways of cell-mediated immunity in response to the fungus.

The invasive and saprophytic syndromes due to Aspergillus spp

Aspergillus spp. produce a wide range of invasive and sapropytic syndromes which may involve any tissue. Within a given tissue or organ the pathology and pathogenesis varies enormously, ranging from angioinvasive disease to noninvasive saprophytic disease. The individual invasive and saprophytic syndromes in which a causative role can be attributed to Aspergillus spp. are detailed specifically with reference to the underlying pathology and pathogenesis, the clinical setting and features, and the manner in which a diagnosis can be established.

Anti-Aspergillus fumigatus efficacy of pentraxin 3 alone and in combination with antifungals

The collectin pentraxin 3 (PTX3) is an essential component of host resistance to pulmonary aspergillosis. Here we examined the protective effects of administration of PTX3 alone or together with deoxycholate amphotericin B (Fungizone) or liposomal amphotericin B (AmBisome) against invasive aspergillosis in a murine model of allogeneic bone marrow transplantation. PTX3, alone or in combination with the polyenes, was given intranasally or parenterally either before, in concomitance with, or after the intranasal infection with Aspergillus fumigatus conidia. Mice were monitored for resistance to infection and parameters of innate and adaptive T-helper immunity. The results showed the following: (i) complete resistance to infection and reinfection was observed in mice treated with PTX3 alone; (ii) the protective effect of PTX3 was similar or superior to that observed with liposomal amphotericin B or deoxycholate amphotericin B, respectively; (iii) protection was associated with accelerated recovery of lung phagocytic cells and T-helper-1 lymphocytes and concomitant decrease of inflammatory pathology; and (iv) PTX3 potentiated the therapeutic efficacy of suboptimal doses of either antimycotic drug. Together, these data suggest the potential therapeutic use of PTX3 either alone or as an adjunctive therapy in A. fumigatus infections.

Vaccination of mice against invasive aspergillosis with recombinant Aspergillus proteins and CpG oligodeoxynucleotides as adjuvants

In a murine model of invasive pulmonary aspergillosis, dendritic cells (DCs) pulsed with Aspergillus antigens induced the activation of CD4(+) Th1 cells capable of conferring resistance to the infection. Here we show that the combined, local delivery of unmethylated CpG oligodeoxynucleotides (ODNs) and the Asp f 16 Aspergillus allergen resulted in the functional maturation and activation of airway DCs capable of inducing Th1 priming and resistance to the fungus. Therefore, ODNs act as a potent adjuvant for the vaccine-induced protection against the fungus by promoting dominant Th1 response to Aspergillus antigens and allergens.