Conidial heads (Fruiting Bodies) as a hallmark for histopathological diagnosis of angioinvasive aspergillosis

Abstract

Aspergillosis is a mycosis that afflicts immunocompetent and immunocompromised hosts; among the former it exhibits different clinical pictures, and among the latter the infection renders an invasive form of the disease. The histologic diagnosis of invasive aspergillosis is somewhat challenging mostly because of some morphological similarities between other fungi. However, when present, the conidial heads are pathognomonic of aspergillosis. The authors present the case of a 68-year-old woman who was submitted to autologous hematopoietic stem cell transplantation in the pursuit of multiple myeloma treatment. The post-transplantation period was troublesome with the development of severe neutropenia, human respiratory syncytial virus pneumonia, and disseminated aspergillosis, which was suspected because of a positive serum galactomannan antigen determination, and resulted in a fatal outcome. The autopsy findings showed diffuse alveolar damage associated with angioinvasive pulmonary aspergillosis with numerous hyphae and conidial heads in the lung parenchyma histology. The authors call attention to the aid of autopsy in confirming the diagnosis of this deep mycosis, since only the research of the galactomannan antigen may be insufficient and uncertain due to its specificity and of the possibility of false-positive results.

Pneumonia in a patient with lung cancer

“…Although the initial evaluation did not reveal the exact origin of systemic inflammatory response and respective causal agent, the positive galactomannan test was strongly indicative of Infection by Aspergillus [1,3,4]. Biopsy samples of lung tissue were sent to histopathology and bacteriologic studies, and the diagnosis of IPA was finally characterized based on the classical criteria [ [1][2][3][4][5]. In accordance with a previous successful outcome, the authors utilized monotherapy with voriconazole to treat the present case of IPA affecting a patient with lung cancer [3].…”

“…A 64-year-old male with antecedent of right lung adenocarcinoma submitted to chemotherapy and corticosteroids had prolonged febrile neutropenia associated with clinical and radiographic features of pneumonia. Although the initial evaluation did not reveal the exact origin of systemic inflammatory response and respective causal agent, the positive galactomannan test was strongly indicative of Infection by Aspergillus [1,3,4]. Biopsy samples of lung tissue were sent to histopathology and bacteriologic studies, and the diagnosis of IPA was finally characterized based on the classical criteria [ [1][2][3][4][5].…”

“…They mostly highlighted the peculiar microbial spectra of pneumonia in lung cancers and the necessity of considering the main microbial agents before empirical therapy [2]. Diagnosis of IPA is characterized by histopathological finding of hyphae and positive culture; clinical data, imaging and positive serology can yield possible diagnosis [4,5]. The culture positivity is up to 50.0% in bronchoalveolar lavage and 5.0% in blood samples, whereas the galactomannan test has the sensitivity of 82.0% and the specificity of 86.0% [4].…”

“…Prolonged neutropenia is defined when this change persists for more than 10 days [1]. Invasive Pulmonary Aspergillosis (IPA) usually affects individuals with prolonged neutropenia, which has been considered the major risk factor for this severe infection [1][2][3][4][5]. Corticosteroid therapy plays an additional role in severity and duration of neutropenia [1].…”

“…The clinical presentations of this mycosis are allergic bronchopulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, aspergilloma, and invasive aspergillosis [3]. Indicative data of pulmonary aspergillosis are clinical and imaging findings, elevated C-reactive protein and erythrocyte sedimentation rate, and positive galactomannan test [3]; diagnosis of IPA depends on histopathological findings of hyphae and positive culture [4,5]. We report a case of IPA in a male patient previously treated for lung adenocarcinoma, who had lung infection by A. fumigatus related to neutropenia and corticoid therapy.…”