Sandra S. Kramer

Bronchiectasis in Children

Bronchiectasis (BR) is a descriptive term for abnormal, irreversibly dilated, and often thick walled bronchi, usually associated with inflammation. Causes are varied but include cystic fibrosis, aspiration, post infectious airway obstruction, immune abnormalities, immotile cilia, posttransplantation states, and congenital bronchial lesions. Although BR is uncommon in children, it causes significant mortality when present. Following a period of presumed decline due to antibiotics and vaccines, BR may increase in prevalence because of AIDS, organ transplantation complications, and changing patterns of childhood immunization. As with adults, high resolution CT (HRCT) is the most useful imaging tool for diagnosis and evaluation of bronchiectasis in children.

Airway growth after pediatric lung transplantation

BACKGROUND Lung transplantation (LT) has been successfully offered to pediatric patients. Very little is known about the growth of the transplanted lung, especially in the infant population. Computerized tomography (CT) scanning is a simple method for studying pediatric patients who have undergone LT. We evaluated the use of CT scans to assess airway growth after pediatric LT, compare airway diameter indexed to somatic growth between LT patients and normals, and compare the growth of pre-anastomotic and post-anastomotic airways indexed to somatic growth in pediatric LT patients. METHODS We reviewed CT scans on all pediatric patients who underwent primary LT before their fifteenth birthday between January 1995 and September 1998. Uniform measurements of diameter were made in pre-anastomotic (trachea, and proximal right and left bronchi) and post-anastomotic (distal right and left bronchi) sites. These measurements were then correlated with height and compared to previously published normal values. RESULTS Of the 16 patients who underwent LT during the study period, 11 had at least 2 sequential CT scans (LT age 3 months to 14 years, median 2 years). Thirty-one CT scans were reviewed. Inter-observer variability was within 1 standard deviation (2 mm) in 93% of the measurements and inter-observer reliability was 0.91 by analysis of variance. Tracheal transverse diameter plotted against body height (slope 0.0072, correlation coefficient 0.88) was virtually identical to previously published norms. A similar relationship between airway diameter and height was observed in pre-anastomotic and post-anastomotic segments. CONCLUSION CT scanning is a reliable method for assessing airway growth in pediatric LT recipients. Tracheal growth in pediatric LT recipients is similar to that of normal children. Post-anastomotic large airways grow similarly to native, pre-anastomotic airways.

Bronchial diseases and lung aeration in children.

Bronchial diseases are common in children, and are usually associated with disturbances of aeration. This article briefly summarizes the embryological development and respiratory physiology pertinent to pediatric bronchial diseases. Current diagnostic imaging tools are discussed, with an emphasis on CT, which can demonstrate bronchial pathology such as bronchial obstruction and bronchiectasis in larger bronchi, as well as indirectly show the peripheral physiologic consequences of bronchial disease, such as alterations in aeration. Computed tomography measurements of lung attenuation may aid in diagnosis in problematic cases. Diseases that affect the pediatric airways at different ages are reviewed. Knowledge of these entities is important for accurate interpretation of imaging studies.

Sporadic adenocarcinoma of the colon in children: case series and review of the literature.

Background: Adenocarcinoma of the colon is rare in pediatric patients and thus not much is known about its clinical and imaging characteristics. Observations: We present 4 adolescents with an average age of 15 years who present with several month histories of significant weight loss and abdominal pain. All had an abdominal and pelvic computed tomography scan, which revealed an adenocarcinoma in the colon. One patient had metastatic disease at diagnosis. The main treatment was primary resection and chemotherapy. Two of the children had a family history of colon cancer. Our case series depicts similarities and differences in disease presentation, tumor location, pattern of metastasis, genetics, management between adults and children and conducts a review of the relevant literature concerning adenocarcinoma in the pediatric population. Conclusions: In children, this disease has more aggressive histologies and presents more frequently in an advanced stage. This is because it is not a diagnosis often considered, leading to poorer outcomes. When patients present in the correct clinical context, the possibility of colonic adenocarcinoma should be considered in the differential diagnosis, which may in turn lead to better outcomes.

Physiologic imaging of the lung with volumetric high-resolution CT

The combination of high-resolution computed tomography (HRCT), rapid volumetric scanning, and advanced image display and analysis applications software is a powerful potential tool for the evaluation of physiologic and pharmacologic events in the lung. Currently employed in the experimental setting, this tool can provide verifiable and quantifiable information about regional responses in the lung, which were previously impossible to demonstrate. This is particularly true when physiologic or pharmacologic effects result in an anatomic change that can be directly imaged and measured within the limits of CT resolution. However, information about events occurring beyond resolution limits is potentially available indirectly from lung density and pulmonary blood flow measurements using CT techniques. The results of animal airway reactivity experiments making use of i.v. methacholine and CT imaging tools are presented as an example of “physiologic imaging.”

The pediatric airway.

Accurate diagnosis is important in the evaluation of airway disorders of infants and children. Today, multiple imaging techniques are available to evaluate the pediatric airway. In general, it is best to start with simple and readily available examinations, which may provide a diagnosis in most cases, and progress to more sophisticated studies only in cases where needed.

Three-dimensional imaging of the pediatric airway

Accurate imaging of the pediatric tracheobronchial tree is indicated for the evaluation of congenital or acquired abnormalities. Conventional axial computed tomography (CT) is now considered the best imaging modality for evaluation of the trachea and major bronchi, and has almost completely replaced the former gold standard of tracheobronchography. Preliminary results indicate that CT scan performance is further enhanced through the application of spiral technology and two-dimensional (2D) and 3D representation of the tracheobronchial tree. Spiral CT scans with 3D surface rendering offers an opportunity to replace traditional tracheobronchography with a safer, less invasive modality.

Factitious fungus in two children with cancer receiving liposomal amphotericin.

Amphotericin B deoxycholate and liposomal formulations of amphotericin are often started and continued empirically, in immunocompromised hosts, based on the computed tomography findings and the patients clinical picture. The authors describe two patients with presumed fungal pulmonary nodules, which were progressive despite prolonged treatment with liposomal amphotericin B. At subsequent biopsy, neither had evidence of active fungal disease; rather, the nodules revealed reactive changes and lipid-laden macrophages. These cases underscore the importance of establishing a microbiologic diagnosis in cases of presumed fungal infection.