Case 28-2019: A 22-Year-Old Woman with Dyspnea and Chest Pain

Secondary spontaneous pneumothorax as the presenting manifestation of filamin A-associated lung disease

Secondary pneumothorax due to early-onset emphysema can be a presenting feature of filamin A mutation. https://bit.ly/3ycAeCs.

Heterogenous Disease Course and Long-Term Outcome of Children's Interstitial Lung Disease Related to Filamin A Gene Variants

Rationale: Variable disease course and outcomes have been reported in children's interstitial lung disease associated with FLNA (Filamin A gene) variants. Objectives: To further delineate long-term respiratory outcomes and identify potential contributing factors to severe disease course. Methods: We retrospectively collected longitudinal data from three centers on nine cases (one male) with FLNA variants and early respiratory disease onset (within the first 24 mo of life). Clinical, radiographic, and histopathologic data were analyzed, focusing on cardiorespiratory disease course. Results: All required early respiratory support (three invasive ventilation, three noninvasive ventilation, three supplemental oxygen), and all experienced frequent severe infective respiratory exacerbations. Three died in infancy from refractory respiratory failure and pulmonary hypertension (PH). The six surviving individuals were 3, 10, 11, 15, 18, and 33 years old at time of reporting. The extent of functional respiratory impairment decreased with age; at last follow-up, there were no individuals on home invasive ventilation, one on nocturnal noninvasive ventilation, four on oxygen, and one on no respiratory support. Spirometry consistently demonstrated moderate to severe obstructive defects (forced expiratory volume in 1 s/forced vital capacity [FVC] z-score, -3.76 to -1.77; percent predicted FVC, 31.5% to 92.1%). Seven required PH treatment in early childhood (7/9), and three of the survivors (3/6) still receive treatment. Radiologic and histopathologic findings were consistent among cases. Conclusions: Early mortality was common, but many survivors stabilized even after severe symptoms in infancy. All survivors had persistent obstructive defects on spirometry, and half have persistent or recurrent PH. These typical findings are suggestive of this rare diagnosis and should prompt consideration of genetic testing.

Application of lung volume reduction surgery for a child with filamin A (FLNA) mutations

Diffuse lung disease in early childhood due to mutations in the filamin A gene has been recently reported. Clinical outcomes vary among individuals indicating variability in phenotype but a substantial proportion of reported cases in early life have ended up in death or lung transplantation. We recently encountered a school-aged child in whom the diagnosis of a filamin A mutation was delayed and the natural history of emphysematous lung disease was altered by serial lung volume reduction surgeries. She eventually underwent a bilateral lung transplant and we report the natural history of her disease and treatments applied herein.

Heterogeneous Pulmonary Phenotypes in Filamin A Mutation-Related Lung Disease

Background: Interstitial lung disease (ILD) has been recently reported in a few patients with pathogenic variants in the Filamin A (FLNA) gene with variable presentation and prognosis. This study evaluated the respiratory manifestations and clinical features in children with FLNA disease. Methods: We conducted a retrospective review of pediatric patients with variants in FLNA in a tertiary children's hospital. The clinical features, genotype, management, and outcomes were analyzed. Results: We identified 9 patients with variants in FLNA aged 15 months to 24 years, 4 females and 5 males. Six patients had abnormal chest imaging ranging from mild interstitial prominence to atelectasis, interstitial densities, and hyperinflation. Three patients with ILD presented during the neonatal period or early infancy with respiratory distress or respiratory failure requiring supplemental oxygen or assisted ventilation via tracheostomy. We report male twins with the same FLNA variant and lung disease, but different ages and clinical features at presentation eventually culminating in respiratory failure requiring assisted ventilation. All patients had FLNA variants identified by FLNA sequencing, had abnormal echocardiograms, and none of the patients underwent lung biopsy or lung transplantation. The outcomes were variable and could be as severe as chronic respiratory failure. Conclusion: The wide spectrum of respiratory manifestations and abnormal chest imaging in our study highlights the importance of evaluation for lung disease in patients with variants in FLNA. FLNA sequencing in suspected cases with ILD may obviate the need for a lung biopsy, prompt surveillance for progressive lung disease, and evaluation for associated clinical features.

Filamin A Mutations: A New Cause of Unexplained Emphysema in Adults?

Emphysema is a chronic respiratory disorder characterized by destruction of alveoli, usually due to cigarette smoking or exposure to noxious particles or gases. Dysfunction of proteins that are involved in lung development and maintenance, such as alpha-1 antitrypsin, also contributes to emphysema. Filamin A (FLNA) is an actin-binding protein involved in cytoskeleton reorganization. Mutations in the FLNA gene classically lead to abnormal neuronal migration and connective and vascular tissue anomalies. Pulmonary manifestations consist of a wide range of pulmonary disorders that occur during infancy. We report the first familial case of emphysema in non- and very low-smoking adults who carry a loss-of-function mutation of the FLNA gene. The identification of this new risk factor for emphysema encourages (1) screening, prevention and monitoring of pulmonary disorders in patients with FLNA mutation and (2) screening for FLNA mutation in patients with early-onset emphysema that is associated with low-smoking or vascular or connective tissue anomalies.

Recognizing genetic disease: A key aspect of pediatric pulmonary care

Advancement in technology has improved recognition of genetic etiologies of disease, which has impacted diagnosis and management of rare disease patients in the pediatric pulmonary clinic. This review provides an overview of genetic conditions that are likely to present with pulmonary features and require extensive care by the pediatric pulmonologist. Increased familiarity with these conditions allows for improved care of these patients by reducing time to diagnosis, tailoring management, and prompting further investigation into these disorders.