Allergic bronchopulmonary aspergillosis with atopic, nonatopic, and sans asthma-Factor analysis

Eosinophilic mucus diseases

Eosinophilic inflammation is primarily characterized by type 2 immune responses against parasitic organisms. In the contemporary human being especially in developed countries, eosinophilic inflammation is strongly associated with allergic/sterile inflammation, and constitutes an undesired immune reaction. This situation is in stark contrast to neutrophilic inflammation, which is indispensable for the host defense against bacterial infections. Among eosinophilic inflammatory disorders, massive accumulation of eosinophils within mucus is observed in certain cases, and is often linked to the distinctive clinical finding of mucus with high viscosity. Eosinophilic mucus is found in a variety of diseases, including chronic allergic keratoconjunctivitis, chronic rhinosinusitis encompassing allergic fungal sinusitis, eosinophilic otitis media, eosinophilic sialodochitis, allergic bronchopulmonary aspergillosis/mycosis, eosinophilic plastic bronchitis, and eosinophilic asthma. In these pathological conditions, chronic inflammation and tissue remodeling coupled with irreversible organ damage due to persistent adhesion of toxic substances and luminal obstruction may impose a significant burden on the body. Eosinophils aggregate in the hyperconcentrated mucus together with cell-derived crystals, macromolecules, and polymers, thereby affecting the biophysical properties of the mucus. This review focuses on the clinically significant challenges of mucus and discusses the consequences of activated eosinophils on the mucosal surface that impact mucus and persistent inflammation.

Epidemiology of the relationship between allergic bronchopulmonary aspergillosis and asthma

PURPOSE OF REVIEW

Allergic bronchopulmonary aspergillosis (ABPA) can complicate the natural history of asthmatic patients, especially the more severe ones, worsening disease control and increasing the need for therapies, steroids in particular, and medical care. The aim of the present review is to summarize the latest epidemiological data related to the relationship between asthma and ABPA and to offer a summary of the most recent strategies that could potentially facilitate in the identification of ABPA in asthmatic patients.

RECENT FINDINGS

In the last years, great efforts have been made by researchers worldwide to provide reliable epidemiological data on fungal sensitization and ABPA, especially in severe asthma patients both in adult and pediatric population. Data differ depending on the geographical area and population studied, but pooled data show a concerning 11% of severe asthma patients having ABPA and one out of four asthmatic patients being sensitized to fungi, Aspergillus fumigatus in particular.

SUMMARY

Reliable epidemiological data and advances in the diagnostic procedures can facilitate the detection of ABPA among asthmatic patients, improving the management of a still under-recognized and challenging condition.

Revised ISHAM-ABPA working group clinical practice guidelines for diagnosing, classifying and treating allergic bronchopulmonary aspergillosis/mycoses

BACKGROUND

The International Society for Human and Animal Mycology (ISHAM) working group proposed recommendations for managing allergic bronchopulmonary aspergillosis (ABPA) a decade ago. There is a need to update these recommendations due to advances in diagnostics and therapeutics.

METHODS

An international expert group was convened to develop guidelines for managing ABPA (caused by Aspergillus spp.) and allergic bronchopulmonary mycosis (ABPM; caused by fungi other than Aspergillus spp.) in adults and children using a modified Delphi method (two online rounds and one in-person meeting). We defined consensus as ≥70% agreement or disagreement. The terms "recommend" and "suggest" are used when the consensus was ≥70% and <70%, respectively.

RESULTS

We recommend screening for A. fumigatus sensitisation using fungus-specific IgE in all newly diagnosed asthmatic adults at tertiary care but only difficult-to-treat asthmatic children. We recommend diagnosing ABPA in those with predisposing conditions or compatible clinico-radiological presentation, with a mandatory demonstration of fungal sensitisation and serum total IgE ≥500 IU·mL-1 and two of the following: fungal-specific IgG, peripheral blood eosinophilia or suggestive imaging. ABPM is considered in those with an ABPA-like presentation but normal A. fumigatus-IgE. Additionally, diagnosing ABPM requires repeated growth of the causative fungus from sputum. We do not routinely recommend treating asymptomatic ABPA patients. We recommend oral prednisolone or itraconazole monotherapy for treating acute ABPA (newly diagnosed or exacerbation), with prednisolone and itraconazole combination only for treating recurrent ABPA exacerbations. We have devised an objective multidimensional criterion to assess treatment response.

CONCLUSION

We have framed consensus guidelines for diagnosing, classifying and treating ABPA/M for patient care and research.

High attenuation mucus in bronchi with allergic bronchopulmonary mycosis

BACKGROUND

High-attenuation mucus (HAM) is a specific manifestation of allergic bronchopulmonary mycosis (ABPM) on chest computed tomography (CT).

OBJECTIVES

To compare the diagnostic accuracy of the two definitions of HAM and to clarify the clinical and radiographic characteristics of HAM-positive and HAM-negative ABPM.

METHODS

CT images at the diagnosis of ABPM using Asano's criteria were retrospectively analysed. In Study #1, radiographic data obtained using the same CT apparatus in a single institute were analysed to determine the agreement between the two definitions of HAM: a mucus plug that is visually denser than the paraspinal muscles or that with a radiodensity ≥70 Hounsfield units. In Study #2, HAM was diagnosed by comparison with the paraspinal muscles in patients with ABPM reporting to 14 medical institutes in Japan.

RESULTS

In Study #1, 93 mucus plugs from 26 patients were analysed. A substantial agreement for HAM diagnosis was observed between the two methods, with a κ coefficient of 0.72. In Study #2, 60 cases of ABPM were analysed; mucus plugs were present in all cases and HAM was diagnosed in 45 (75%) cases. The median A. fumigatus-specific IgE titre was significantly lower in HAM-positive patients than in HAM-negative patients (2.5 vs. 24.3 UA /mL, p = .004). Nodular shadows were observed more frequently in the airways distal to HAM than in those distal to non-HAM mucus plugs (59% vs. 32%, p < .001).

CONCLUSION

In conclusion, agreement between the two methods to diagnose HAM was substantial. HAM was associated with some immunological and radiographic characteristics, including lower levels of sensitization to A. fumigatus and the presence of distal airway lesions.

Allergic bronchopulmonary aspergillosis manifested secondary to bacterial pleural empyema

A 54-year-old woman with no history of lung disease including bronchial asthma developed left bacterial pleural empyema due to the perforation of a lung abscess in the left lower lobe. Chest tube drainage and antibiotics improved the pleural empyema. Two months following discharge from the hospital, she developed a cough and left chest pain. Chest computed tomography revealed high-attenuation mucus plugs, atelectasis in the left lower lobe, and an increased peripheral blood eosinophil count. Bronchoscopy revealed a mucoid impaction in B8 of the left lower lobe, confirming the presence of Aspergillus fumigatus. A diagnosis of allergic bronchopulmonary aspergillosis was made, and treatment with oral prednisolone was initiated, resulting in the resolution of the mucus plugs and improvement of atelectasis.