Interventional Chest/Diagnostic Procedures
Cryobiopsy for ILD: Careful stewardship needed
Interest in transbronchial cryobiopsy has accelerated rapidly in recent years. This procedure is performed by advancing a cryoprobe into the peripheral lung via flexible bronchoscopy, where lung tissue freezes and adheres to the probe and is subsequently extracted as a cryobiopsy. The number of cryobiopsy-related publications has increased exponentially since it was described in 2009 (Babiak A, et al. Respiration. 2009;78:203). This interest stems from reports of high diagnostic yields in patients with interstitial lung disease (ILD) while maintaining complication rates similar to that of conventional bronchoscopic biopsy.
Traditional bronchoscopic biopsies are notoriously insensitive; a specific diagnosis can be established in fewer than a third of cases (Sheth JS, et al. Chest. 2017;151:389). As such, surgical lung biopsy continues to be recommended but is associated with significant mortality (2%) and morbidity (30%) in patients with ILD (Hutchinson JP, et al. ARJCCM. 2016;193:1161). Cryobiopsy, which appears to rival surgical lung biopsy in terms of ability to contribute to a specific diagnosis, is, therefore, a highly promising alternative (Tomassetti S, et al. AJRCCM. 2016;193:745).
As cryobiopsy is increasingly adopted around the world, however, troubling reports of serious complications have surfaced. Most notable is the recently reported experience of the initial 25 cases performed at the University of Pennsylvania, in which almost one in four patients suffered serious complications (DiBardino DM, et al. Ann Am Thorac Soc. 2017;14:851). The authors pointed to lack of a predefined procedural protocol, as well as several choices relating to the specific technique used, including inconsistent use of fluoroscopy, lack of prophylactic bronchial blocker placement, and predominant use of laryngeal mask airways as potential contributing factors. Indeed, many variations of the basic cryobiopsy procedure have been described (Lentz RJ, et al. J Thoracic Dis. 2017;9:2186), with no formal guidance or training available to inform advanced bronchoscopists interested in this procedure.
It is incumbent on the interventional pulmonology and ILD specialist communities to be responsible stewards of this promising procedure. Implementation of three parallel efforts to standardize and rigorously study this procedure should be considered as soon as possible: creation of expert consensus guidelines establishing best-practices for safe and effective biopsy technique; a training requirement before independent performance of the procedure; and creation of an international cryobiopsy registry to facilitate higher-quality research into optimal technique and outcomes. We owe this to our patients.
Robert J. Lentz, MD
Fabien Maldonado, MD, FCCP
Pediatric Chest Medicine
Chronic cough in children: New guidelines
A chronic cough is a common complaint among children whose parents seek medical evaluation. Chronic wet cough can indicate an underlying illness; therefore, an early diagnosis can lead to prevention of complications of the disease and improvement in quality of life.
CHEST is a leading resource in evidence and consensus-based guidelines on important topics affecting children. The most recent guidelines entitled Management of Children with Chronic Wet Cough and Protracted Bacterial Bronchitis (Chest. 2017;151(4):884-890) and Use of Management Pathways or Algorithms in Children with Chronic Cough (Chest. 2017;151(4):875-873) are updates from the 2006 CHEST guidelines on chronic cough in children.
The present updates utilized the CHEST methodological guidelines with chronic wet or productive cough and Grading of Recommendations Assessment, Development, and Evaluation framework and also performed a systematic review addressing key questions concerning the management of childhood disease for children 14 years and younger.
Guidance provided by the expert panel focused on recommendations to answer six key questions concerning the management of children 14 years and younger with a chronic wet cough unrelated to established chronic lung disease. The recommendations are:
1. Chronic cough is defined as the presence of a cough 4 weeks or longer in duration.
2. Assessment of the effect of the cough on the child and the family be undertaken as part of clinical consultation.
3. Evaluation of a chronic cough should be done with a systematic approach with pediatric-specific cough management protocols or algorithms.
4. Chest radiograph and, when age appropriate, spirometry with bronchodilator be undertaken as evaluation; tests for pertussis infection only to be performed if clinically suspected.
5. Chronic wet cough with no specific clinical features should receive antibiotics for 2 weeks targeted for common respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis).
6. When cough persists despite 2 weeks of appropriate antibiotics, it is recommended to continue for an additional 2 weeks.
7. Additional tests (eg skin prick test, Mantoux, bronchoscopy, chest CT scan) should be individualized in accordance with the clinical setting and child’s clinical symptoms and signs.
The panel recognizes the need for prospective studies to assess current algorithms outcomes of children with chronic cough. Both articles can be found on the guidelines section of the CHEST site.
John Bishara, DO