Childhood diffuse parenchymal lung diseases: We need a new classification

Childhood interstitial lung disease in Turkey: first data from the national registry

The childhood interstitial lung diseases (chILD) Turkey registry (chILD-TR) was established in November 2021 to increase awareness of disease, and in collaboration with the centers to improve the diagnostic and treatment standards. Here, the first results of the chILD registry system were presented. In this prospective cohort study, data were collected using a data-entry software system. The demographic characteristics, clinical, laboratory, radiologic findings, diagnoses, and treatment characteristics of the patients were evaluated. Clinical characteristics were compared between two main chILD groups ((A) diffuse parenchymal lung diseases (DPLD) disorders manifesting primarily in infancy [group1] and (B) DPLD disorders occurring at all ages [group 2]). There were 416 patients registered from 19 centers. Forty-six patients were excluded due to missing information. The median age of diagnosis of the patients was 6.05 (1.3-11.6) years. Across the study population (n = 370), 81 (21.8%) were in group 1, and 289 (78.1%) were in group 2. The median weight z-score was significantly lower in group 1 (- 2.0 [- 3.36 to - 0.81]) than in group 2 (- 0.80 [- 1.7 to 0.20]) (p < 0.001). When we compared the groups according to chest CT findings, ground-glass opacities were significantly more common in group 1, and nodular opacities, bronchiectasis, mosaic perfusion, and mediastinal lymphadenopathy were significantly more common in group 2. Out of the overall study population, 67.8% were undergoing some form of treatment. The use of oral steroids was significantly higher in group 2 than in group 1 (40.6% vs. 23.3%, respectively; p = 0.040).   Conclusion: This study showed that national registry allowed to obtain information about the frequency, types, and treatment methods of chILD in Turkey and helped to see the difficulties in the diagnosis and management of these patients. What is Known: • Childhood interstitial lung diseases comprise many diverse entities which are challenging to diagnose and manage. What is New: • This study showed that national registry allowed to obtain information about the frequency, types and treatment methods of chILD in Turkey and helped to see the difficulties in the diagnosis and management of these patients. Also, our findings reveal that nutrition should be considered in all patients with chILD, especially in A-DPLD disorders manifesting primarily in infancy.

Childhood Interstitial Lung Disease

Childhood interstitial lung disease (chILD) is a heterogeneous group of diseases with various clinical and imaging findings. The incidence and prevalence have increased in recent years, probably due to better comprehension of these rare diseases and increased awareness among physicians. chILDs present with nonspecific pulmonary symptoms, such as tachypnea, hypoxemia, cough, rales, and failure to thrive. Unnecessary invasive procedures can be avoided if specific mutations are detected through genetic examinations or if typical imaging patterns are recognized on computed tomography. Disease knowledge and targeted therapies are improving through international collaboration. Pulmonary involvement in systemic diseases is not uncommon. Pulmonary involvement may be the first finding in connective tissue diseases. This review aims to present a systematic patient-targeted approach to the diagnosis of chILD.

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.

Etiologic Classification of Diffuse Parenchymal (Interstitial) Lung Diseases

Interstitial lung diseases (ILD) or diffuse parenchymal lung diseases (DPLD) comprise a large number of disorders. Disease definition and classification allow advanced and personalized judgements on clinical disease, risks for genetic or environmental transmissions, and precision medicine treatments. Registers collect specific rare entities and use ontologies for a precise description of complex phenotypes. Here we present a brief history of ILD classification systems from adult and pediatric pneumology. We center on an etiologic classification, with four main categories: lung-only (native parenchymal) disorders, systemic disease-related disorders, exposure-related disorders, and vascular disorders. Splitting diseases into molecularly defined entities is key for precision medicine and the identification of novel entities. Lumping diseases targeted by similar diagnostic or therapeutic principles is key for clinical practice and register work, as our experience with the European children’s ILD register (chILD-EU) demonstrates. The etiologic classification favored combines pediatric and adult lung diseases in a single system and considers genomics and other -omics as central steps towards the solution of “idiopathic” lung diseases. Future tasks focus on a systems’ medicine approach integrating all data and bringing precision medicine closer to the patients.

Clinical spectrum of children with interstitial pneumonia with autoimmune features

BACKGROUND

Interstitial pneumonia with autoimmune features (IPAF) is a term used to describe adult patients with interstitial lung disease (ILD) who display some clinical or serological features of autoimmune diseases and who do not meet the full criteria for a specific connective tissue disease (CTD). The aim of this study was to define the demographic, clinical, radiologic, serologic and histopathologic features and assess treatment in children with IPAF.

METHODS

This retrospective cohort study was conducted at a tertiary referral pediatric pulmonology center between January 2010 and August 2020. Children with proven interstitial pneumonia with no known etiologies were evaluated for IPAF according to European Respiratory Society/American Thoracic Society research statement of IPAF.

RESULTS

Among 132 children with ILD, 17 patients were evaluated in detail for IPAF criteria and six patients were further diagnosed as having IPAF. The incidence of IPAF in our patients with ILD was 4.5%. Four of these patients were female. The median age at the time of ILD diagnosis was 10.5 years. The most common initial symptom was shortness of breath, and the most common physical examination sign was crackles in both lungs. Steroid therapy was given to all patients and four patients received other immunosuppressive agents for steroid sparing. Two of those patients died because of respiratory insufficiency during the follow-up.

CONCLUSION

Children with interstitial pneumonia and certain clinical, serologic, and/or morphologic features should raise suspicion for the presence of an underlying systemic autoimmune disease. IPAF is also seen in children and should be categorized in chILD classifications.