Usefulness of bronchoalveolar lavage in a French pediatric cohort with hypersensitivity pneumonitis

Clinical radiological and pathological staging of children with hypersensitivity pneumonitis

OBJECTIVE

Hypersensitivity pneumonitis (HP) is rare in the pediatric population. To date, there are no studies defining a correlation between clinical, radiological, and pathological findings in children with HP. The objective of this study is to define the clinical, and radiological characteristics and prognosis of childhood HP and to examine the clinical, radiological, and pathological correlation between HP stages.

METHODS

Patients with suspected HP and followed at two tertiary care hospitals between 2000 and 2020 were retrospectively evaluated. Computed tomography (CT) of the chest of patients was evaluated by a single radiologist. The interagreement between clinical and radiological severity of the patients was calculated with the κ test.

RESULTS

Fourteen children with suspected HP were identified. The results of 10 patients with the definitive diagnosis were as follows: one patient (10%) had acute, five patients (50%) had subacute, and four patients (40%) had chronic HP. The most prominent findings in chest CT were hilar, or hilar and subcarinal lymphadenopathy (80%), centrilobular nodules (60%), patchy or diffuse ground-glass opacities (50%), and cysts (50%). The interagreement between clinical and radiological severity of the patients was 100% (approximate significance: 0.003). The diagnosis of four patients with suspected HP who were unresponsive to standardized medical treatments or developed multisystem involvement was diagnosed with other diseases. One patient (10%) with definitive chronic HP died due to respiratory failure during follow up.

CONCLUSION

Similar to adult HP, the prognosis is worse in children with existing fibrotic equivalents in chest CT. Patients who are not responding to standard medical treatments or develop multisystem involvement should be evaluated for other lung diseases.

Pediatric pulmonology 2020 year in review: Rare and diffuse lung disease

Pediatric Pulmonology publishes original research, review articles, and case reports on topics related to a wide range of children's respiratory disorders. Here we review some of the most notable manuscripts published in 2020 in this journal on (1) children's interstitial lung disease (chILD), (2) congenital airway and lung anomalies, and (3) primary ciliary dyskinesia and other non-cystic fibrosis bronchiectasis. The articles reviewed are discussed in context with published works from other journals.

Pediatric hypersensitivity pneumonitis: literature update and proposal of a diagnostic algorithm

Hypersensitivity pneumonitis (HP) is a rare disease in childhood with the prevalence of 4 cases per 1 million children and an incidence of 2 cases per year. The average age of diagnosis at pediatric age is approximately 10 years. The pathogenesis of HP is characterized by an immunological reaction caused by recurrent exposure to triggering environmental agents (mostly bird antigens in children). The clinical picture of HP is complex and variable in children, often presenting in subacute forms with cough and exertion dyspnea. A diagnosis of HP should be considered in patients with an identified exposure to a triggering antigen, respiratory symptoms, and radiologic signs of interstitial lung disease. Blood tests and pulmonary function tests (PFT) support the diagnosis. Bronchoscopy (with bronchoalveolar lavage and tissue biopsy) may be needed in unclear cases. Antigen provocation test is rarely required. Of note, the persistence of symptoms despite various treatment regimens may support HP diagnosis. The avoidance of single/multiple triggers is crucial for effective treatment. No evidence- based guidelines for treatment are available; in particular, the role of systemic glucocorticoids in children is unclear. With adequate antigen avoidance, the prognosis in children with HP is generally favorable.

Early-onset, fatal interstitial lung disease in STAT3 gain-of-function patients

Gain-of-function variants in STAT3 are known to cause severe, multifaceted autoimmunity. Here we report three individuals with de-novo STAT3 GOF alleles and early-onset, severe interstitial lung disease manifesting during the first 3 years of life. Imaging and histology revealed different forms of interstitial pneumonia alongside fibrotic and cystic tissue destruction. Definitive diagnosis was established by postmortem whole exome sequencing and functional validation of two new STAT3 variants. Such lung-predominant forms of STAT3 GOF disease expand the phenotypic spectrum of diseases associated with activating STAT3 variants and add to our understanding of this life-threatening inborn error of immunity.

Clinical Features of Hypersensitivity Pneumonitis in Children: A Single Center Study

BACKGROUND

Hypersensitivity pneumonia (HP) is an interstitial lung disease (ILD) mainly involving small airways and lung parenchyma that is caused by the inhalation of antigens in susceptible people to stimulate the body's immune response.

METHODS

A total of 6 Chinese children with HP treated in our center from July 2017 to July 2021 were included in our study.

RESULTS

Among the children, there were 4 males and 2 females, ranging in age from 4 to 14 years. Three cases had chest tightness and shortness of breath, 2 cases had cough, 1 case had chest pain, and 1 case had fever. Two cases of children had a history of close contact with pet dogs, 1 case had a history of contact with pigeons, 2 cases lived in a moldy house recently, and 1 case recently played a saxophone that had been idle for more than 2 years. The parents of two cases also had similar symptoms recently. The specific signs of chest HRCT of 6 cases all were in line with the characteristics of HP. After avoiding the sensitization environment, 2 children quickly recovered, 4 patients received low-dose glucocorticoid oral treatment, and after symptom control the dose was gradually reduced. The course of treatment was about 3-6 months.

CONCLUSIONS

Exposure to a potential antigen has been found in all 6 HP children. The clinical manifestations are heterogeneous and easy to confuse with other diseases. A clear history of exposure to the antigens, respiratory symptoms associated with HP, signs of HP on HRCT, and improvement after removal from the antigenic environment constitute the cornerstone of the diagnosis of HP children in our unit. Avoiding exposure to antigenic environment is the first step in treatment, and glucocorticoid use is necessary in children with persistent symptoms.