Could CT scan avoid unnecessary flexible bronchoscopy in children with active pulmonary tuberculosis? A retrospective study

Comparison of single coronal thick-slab minimum intensity projection with flexible bronchoscopy for airway compression in children with lymphobronchial tuberculosis

AIM

To generate standardised coronal minimum intensity projection (MinIP) computed tomography (CT) reconstructions, and compare these with flexible bronchoscopy in children with lymphobronchial tuberculosis (LBTB).

MATERIALS AND METHODS

Standardised coronal MinIP reconstructions were performed from CT images in children with LBTB and the findings of three readers were compared with the reference standard, flexible bronchoscopy (FB), regarding airway narrowing. Intraluminal lesions, the site of the stenosis, and the degree of stenosis were also evaluated. The length of stenosis was evaluated by CT MinIP only.

RESULTS

Sixty-five children (38 males; 58.5% and 27 females; 41.5%), with ages ranging from 2.5 to 144 months were evaluated. Coronal CT MinIP demonstrated a sensitivity of 96% and specificity of 89% against FB. The most common site of stenosis was the bronchus intermedius (91%), followed by the left main bronchus (85%), the right upper lobe bronchus RUL (66%), and the trachea (60%).

CONCLUSION

Coronal CT MinIP reconstruction is useful in demonstrating airway stenosis in children with lymphobronchial TB, with high sensitivity and specificity. CT MinIP had additional advantages over FB in that it allowed objective measurement of the diameter of stenosis, measurement of the length of stenosis, and evaluation of post-stenotic segments of the airways and lung parenchymal abnormalities.

Complicated intrathoracic tuberculosis: Role of therapeutic interventional bronchoscopy

In recent years bronchoscopy equipment has been improved with smaller instruments and larger size working channels. This has ensured that bronchoscopy offers both therapeutic and interventional options. As the experience of paediatric interventional pulmonologists continues to grow, more interventions are being performed. There is a scarcity of published evidence in the field of interventional bronchoscopy in paediatrics. This is even more relevant for complicated pulmonary tuberculosis (PTB). Therapeutic interventional bronchoscopy procedures can be used in the management of complicated tuberculosis, including for endoscopic enucleations, closure of fistulas, dilatations of bronchial stenosis and severe haemoptysis. Endoscopic therapeutic procedures in children with complicated TB may prevent thoracotomy. If done carefully these interventional procedures have a low complication rate.

The role of bronchoscopy in the diagnosis and management of pediatric pulmonary tuberculosis

Bronchoscopy is useful as a diagnostic and therapeutic procedure in children with Tuberculosis (TB) disease complicated by airway obstruction. It is needed in children when surgical intervention may be required for airway compression, when drug resistance is suspected, and to rule out an alternative diagnosis for airway obstruction. Bronchoscopy with bronchoalveolar lavage (BAL) should be performed when other, less invasive samples cannot be collected, or when they fail to provide useful diagnostic information. BAL specimens collected at bronchoscopy can be tested using molecular TB assays and mycobacterial culture. The aim of this review is to evaluate the role of bronchoscopy in the diagnosis and management of pulmonary TB in children, and, specifically, to review the role of interventional bronchoscopy. A search of electronic databases was undertaken using the online databases PubMed, Ovid MEDLINE, EMBASE, Google Advanced Scholar, and Web of Science to identify relevant literature. The search was limited to pediatrics, pulmonology, bronchoscopy, and pediatric pulmonary tuberculosis for all articles published in English on pediatric bronchoscopy between 2010 and 2020. Recent advances in pediatric bronchoscopy was included, as well as recent research on improving the diagnosis with the use of interventional bronchoscopy. The role of bronchoscopy in pediatric pulmonary tuberculosis has changed during the last decade, from a simple method of collecting samples for bacteriological conformation to an more sophisticate procedure. New methods are available for collecting samples, which includes the use of Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and also better methods of bacteriological conformation. Interventions are now possible; not only to improve the diagnostic abilities of bronchoscopy but also to diagnose, manage, and follow-up upon airway-related complications. Bronchoscopy services remain limited in resource-limited countries due to the high cost of equipment.

[Childhood tuberculosis]

Childhood TB is an indication of failing TB control in the community. It allows disease persistence in the population. Mortality and morbidity due to TB is high in children. Moreover, HIV co-infection and multidrug-resistant diseases are as frequent in children as in adults. Infection is more frequent in younger children. Disease risk after primary infection is greatest in infants younger than 2 years. In case of exposure, evidence of infection can be obtained using the tuberculin skin test (TST) or an interferon-gamma assay (IGRA). There is no evidence to support the use of IGRA over TST in young children. TB suspicion should be confirmed whenever possible, using new available tools, particularly in case of pulmonary and lymph node TB. Induced sputum, nasopharyngeal aspiration and fine needle aspiration biopsy provide a rapid and definitive diagnosis of mycobacterial infection in a large proportion of patients. Analysis of paediatric samples revealed higher sensitivity and specificity values of molecular techniques in comparison with the ones originated from adults. Children require higher drugs dosages than adults. Short courses of steroids are associated with TB treatment in case of respiratory distress, bronchoscopic desobstruction is proposed for severe airways involvement and antiretroviral therapy is mandatory in case of HIV infection. Post-exposure prophylaxis in children is a highly effective strategy to reduce the risk of TB disease. The optimal therapy for treatment of latent infection with a presumably multidrug-resistant Mycobacterium tuberculosis strain is currently not known.

Bronchoscopic assessment of airway involvement in children presenting with clinically significant airway obstruction due to tuberculosis

INTRODUCTION

The incidence of complicated lymph node disease in tuberculosis (TB) in children less than 15 years of age varies from 8% to 38%. There are few published studies on the bronchoscopic appearance and severity of airway obstruction caused by lymph node involvement of the airways resulting from Mycobacterium tuberculosis (MTB). The primary aim of the study was to describe the flexible bronchoscopic findings of lymph node involvement of the airways caused by MTB in children with severe airway obstruction. The secondary aim was to compare the degree of airway involvement in HIV negative to HIV positive children as well the airway involvement caused by drug susceptible and drug resistant MTB.

PATIENTS AND METHODS

All children between 1 month and 13 years of age presenting with clinical and radiological signs of significant airway obstruction suspected of being the result of MTB infection were studied. In addition to routine examination for MTB disease a flexible bronchoscope and bronchoalveolar lavage (BAL) for MTB culture were performed on all the children.

RESULTS

Two hundred fifty children (16% HIV positive) were studied. Median age was 14 months and the median weight 8.5 kg. MTB was cultured from 78% (n = 194) of children with the BAL positive in 44%. The BAL culture yield was significantly higher in children with radiological evidence of pneumonia when compared to children with airway involvement alone (P = 0.004). The bronchial tree was obstructed on the right in 85% (n = 212), the left in 66% (n = 164), and both sides in 53% (n = 132) of cases. The commonest sites of obstruction were bronchus intermedius (72%) and left main bronchus (62%). Drug resistance was present in 16% (n = 28). There was no difference in the site or severity of obstruction when comparing drug susceptible to drug resistant cases or HIV positive to HIV negative children.

CONCLUSIONS

Bronchus intermedius and left main bronchus were the commonest sites of airway obstruction. The MTB culture yield from BAL was higher in children with pneumonia when compared to those with airway involvement alone. HIV positive or children with drug resistant TB did not have more severe airway obstruction.

The role of rigid and flexible bronchoscopy in children

Bronchoscopy for paediatric respiratory disease is a routine procedure in paediatric pulmonology. Rigid bronchoscopy is now much less commonly used than flexible bronchoscopy. Technological advances have brought better picture quality and easier storage of video documentation. Indications with clear clinical benefit are congenital or acquired unexplained airway obstruction. In pulmonary infections or infiltrates in immunodeficient or immunosuppressed children not responding to empirical treatment a pathogen may be identified by bronchoscopy and bronchoalveolar lavage (BAL). Bronchoscopy and BAL can be indicated in children with unusual presentations of chronic cough or wheeze, and cystic fibrosis. The use of transbronchial biopsies (TBB) is established in paediatric lung transplantation. New applications and techniques are being developed, such as endobronchial ultrasound and transbronchial needle biopsy of lymph nodes and the role of airway stent placement have become better understood.

[Specific features of tuberculosis in childhood]

Primary infection with Mycobacterium tuberculosis usually occurs during childhood. The source of infection is most often an adult. The risk of infection in exposed children is modulated by various factors related to the infectiousness of the index case, exposure conditions, and the child himself. This review aims to describe the specific diagnostic and therapeutic features of latent TB infection and TB disease in childhood.