Lung Transplantation Biopsy Specimens With Bronchiolitis Obliterans or Bronchiolitis Obliterans Organizing Pneumonia Due to Aspiration

Follow-up on the therapeutic effects of a budesonide, azithromycin, montelukast, and acetylcysteine (BAMA) regimen in children with post-infectious bronchiolitis obliterans

Background

Post-infectious bronchiolitis obliterans (PIBO) is a rare, severe chronic lung disease without optimal treatment. Currently, treatment in children mainly relies on systemic corticosteroids, but long-term use of these drugs may lead to adverse reactions. This study aimed to evaluate the short-term efficacy of the budesonide, azithromycin, montelukast, and acetylcysteine (BAMA) regimen in paediatric PIBO patients and whether it can reduce systemic corticosteroid use.

Methods

This was a prospective study. From June 2017 to July 2020, patients diagnosed with PIBO at Yuying Children’s Hospital of Wenzhou Medical University were treated with the BAMA regimen for 3 months. Methylprednisolone was added only when the clinical manifestations did not improve or deteriorated. All patients were followed up every 2 to 4 weeks, and changes in clinical symptoms were recorded. Pulmonary function tests and high-resolution computed tomography (HRCT) were performed, and systemic corticosteroid use was recorded after the 3-month follow-up.

Results

A total of 75 patients with PIBO were included; overall, 54 patients completed the course of treatment. After treatment, the respiratory manifestations were improved in 37 patients (68.5%), but 4 patients (7.4%) showed decreased exercise tolerance, and 2 patients (3.7%) were readmitted to the hospital. Additionally, 17 (56.7%) of the 30 patients whose pulmonary function was re-examined showed improvement, and 28 (77.8%) of the 36 patients who underwent HRCT showed marked improvement. Importantly, 20 patients (54.1%) received systemic corticosteroids for 2 weeks or less, while 31.5% of patients used no corticosteroids.

Conclusions

The BAMA regimen effectively relieved clinical symptoms and signs of PIBO in children, improved pulmonary function and HRCT manifestations, and reduced the use of systemic corticosteroids.

Parenteral administration of oral medications in lung transplant recipients: An underrecognized problem

Microcrystalline cellulose (MCC) is an insoluble material commonly used as a binder and filler in oral medications. Identification of pulmonary intravascular deposition of MCC in transbronchial biopsies from lung transplant (LT) recipients following parenteral injection of oral medications has only been reported once. A search of our surgical pathology electronic database was performed from January 1, 2000 to November 1, 2017 using the text "transplant transbronchial." The diagnosis field for all cases retrieved was then searched for the text "cellulose." These cases were queried for patient demographics and outcomes. Between January 1, 2000 and November 1, 2017, 1558 lung transplants were performed in 1476 individual patients at our institution; 12 were identified to have MCC in their lung tissue. Patients with MCC identified on biopsies were more likely to be transplanted for cystic fibrosis versus other indications and younger versus older. MCC identified in 2 of our cases was favored to be donor derived. Of the 12 patients, 6 (50%) are deceased. MCC within the pulmonary vasculature may be an indicator of increased complications, mortality, or shortened survival in LT recipients. Detecting intravascular MCC and distinguishing it from aspirated foreign material can be challenging. Awareness of the differential diagnosis for pulmonary foreign material is of paramount importance for the pathologist.

Bronchiolitis obliterans organizing pneumonia, 25 years: a variety of causes, but what are the treatment options?

Bronchiolitis obliterans organizing pneumonia is an inflammatory lung disease involving the distal bronchioles, respiratory bronchioles, bronchiolar ducts and alveoli. Its cause is generally unknown, but there are several known causes and associated systemic diseases. The clinical features include cough, shortness of breath and bilateral crackles. The vital capacity is slightly decreased, and the diffusing capacity is moderately to severely decreased. The high-resolution chest CT scan shows bilateral ground-glass opacities with air bronchograms and triangular, pleura-based opacities. Corticosteroid therapy is the best treatment option. The outcome of patients suffering from bronchiolitis obliterans organizing pneumonia is good, as up to 80% of individuals will be cured.

Revision of the 1996 working formulation for the standardization of nomenclature in the diagnosis of lung rejection

In 1990, an international grading scheme for the grading of pulmonary allograft rejection was adopted by the International Society for Heart and Lung Transplantation (ISHLT) and was modified in 1995 by an expanded group of pathologists. The original and revised classifications have served the lung transplant community well, facilitating communication between transplant centers with regard to both patient management and research. In 2006, under the direction of the ISHLT, a multi-disciplinary review of the biopsy grading system was undertaken to update the scheme, address inconsistencies of use, and consider the current knowledge of antibody-mediated rejection in the lung. This article summarizes the revised consensus classification of lung allograft rejection. In brief, acute rejection is based on perivascular and interstitial mononuclear infiltrates, Grade A0 (none), Grade A1 (minimal), Grade A2 (mild), Grade A3 (moderate) and Grade A4 (severe), as previously. The revised (R) categories of small airways inflammation, lymphocytic bronchiolitis, are as follows: Grade B0 (none), Grade B1R (low grade, 1996, B1 and B2), Grade B2R (high grade, 1996, B3 and B4) and BX (ungradeable). Chronic rejection, obliterative bronchiolitis (Grade C), is described as present (C1) or absent (C0), without reference to presence of inflammatory activity. Chronic vascular rejection is unchanged as Grade D. Recommendations are made for the evaluation of antibody-mediated rejection, recognizing that this is a controversial entity in the lung, less well developed and understood than in other solid-organ grafts, and with no consensus reached on diagnostic features. Differential diagnoses of acute rejection, airway inflammation and chronic rejection are described and technical considerations revisited. This consensus revision of the working formulation was approved by the ISHLT board of directors in April 2007.

Pathology of lung transplantation

The International Society for Heart and Lung Transplantation has a standardized nomenclature for the evaluation of lung allografts. Rejection of the lung allograft is divided into acute and chronic forms. Acute cellular rejection is characterized by perivascular accumulations of mononuclear cells and eosinophils; bronchiolar inflammation is also included in the grading scheme. Acute antibody-mediated rejection in lung allografts is not well defined. Chronic rejection is manifest by fibrous scarring narrowing the lumen of bronchioles, arteries, and veins. The diagnosis of rejection requires the exclusion of infection and other pathology in the allograft.