How I diagnose and treat organizing pneumonia in hematopoietic cell transplant recipients.

Organizing pneumonia (OP) is a known non-infectious pulmonary complication following allogeneic hematopoietic cell transplant (HCT) and represents a significant risk factor for non-relapse mortality in HCT recipients. Unlike bronchiolitis obliterans syndrome, it is not universally acknowledged as a distinctive pulmonary manifestation of chronic-graft-versus-host disease (cGVHD) and therefore, its diagnostic criteria and management approach is lacking. Given it shared similar clinical features, radiological and histological findings to OP in non-HCT population, the diagnostic approach and treatment strategy for OP in HCT recipient is largely adapted from the non-HCT population. In this paper, we aim to enhance the understanding of OP within the context of cGVHD following HCT, distinguish its clinical features and treatment strategy from non-HCT counterpart, thereby reinforcing its recognition as a pulmonary manifestation of GVHD. We will propose the diagnostic criteria and outline our approach in diagnosis and treatment strategy, highlighting the potential challenges that may arise in each process. Finally, we will discuss knowledge gaps in this field and identify the area of need for future research.

Portopulmonary Hypertension.

PoPH is a well-recognized complication of portal hypertension with or without cirrhosis and is classified as a subset of PAH. Identification of PoPH is crucial as it has a major impact on prognosis and liver transplant candidacy. Echocardiogram is the initial screening tool of choice and the patient should proceed to RHC for confirmation. PAH-directed therapy is the treatment of choice, allowing the patient to achieve a hemodynamic threshold to undergo a liver transplant safely.

Epidemiology of Lower Respiratory Tract Infections and Community-Acquired Respiratory Viruses in Patients with Bronchiolitis Obliterans Syndrome after Hematopoietic Cell Transplantation: A Retrospective Cohort Study.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS)-chronic graft-versus-host disease (cGVHD) affecting the lungs-is an uncommon complication of allogeneic hematopoietic cell transplant (HCT). The epidemiology and complications of lower respiratory tract infections (LRTIs) and community-acquired respiratory viruses (CARVs) in these patients are poorly understood. OBJECTIVES: We aim to characterize the epidemiology of LRTIs in patients with BOS complicating HCT. We also aim to explore the association of LRTIs and CARV detection on lung function in BOS patients. STUDY DESIGN: Adult patients with BOS at Stanford Health Care between January 2010 and December 2019 were included in this retrospective cohort study. LRTI diagnosis was based on combined clinical, microbiologic, and radiographic criteria, using consensus criteria where available. RESULTS: Fifty-five patients with BOS were included. BOS was diagnosed at a median of 19.2 (IQR 12.5-24.7) months after HCT, and patients were followed for a median of 29.3 (IQR 9.9-53.2) months from BOS diagnosis. Twenty-two (40%) patients died after BOS diagnosis; 17 patients died from complications of cGVHD (including respiratory failure and infection) and 5 died from relapsed disease. Thirty-four (61.8%) patients developed at least one LRTI. Viral LRTIs were most common, occurring in 29 (52.7%) patients, primarily due to rhinovirus. Bacterial LRTIs-excluding Nocardia and non-tuberculous mycobacteria (NTM)-were the second most common, occurring in 21 (38.2%) patients, mostly due to Pseudomonas aeruginosa. Fungal LRTIs, NTM, and nocardiosis occurred in 14 (25.5%), 10 (18.2%), and 4 (7.3%) patients, respectively. Median time to development of the first LRTI after BOS diagnosis was 15.3 (4.7-44.7) months. Twenty-six (76.5%) of the 34 patients who developed LRTIs had infections due to more than one type of organism-fungi, viruses, Nocardia, NTM, and other bacteria-over the observation period. Patients with at least one LRTI had significantly lower forced expiratory volume in one second percent predicted (FEV1%) (37% vs. 53%, p = 0.0096) and diffusing capacity of carbon monoxide (DLCO) (45.5% predicted vs. 69% predicted, p = 0.0001). Patients with at least one LRTI trended toward lower overall survival (OS) (p = 0.0899) and higher non-relapse mortality (NRM) (p = 0.2707). Patients with a CARV detected or LRTI diagnosed after BOS-compared to those without any CARV detected or LRTI diagnosed-were more likely to have a sustained drop in FEV1% from baseline of at least 10% (21 [61.8%] versus 7 [33.3%]) and a sustained drop in FEV1% of at least 30% (12 [36.4%] versus 2 [9.5%]). CONCLUSIONS: LRTIs are common in BOS and associated with lower FEV1%, lower DLCO, and a trend toward decreased OS and higher NRM. Patients with LRTIs or CARVs (even absent lower respiratory tract involvement) were more likely to have substantial declines in FEV1% over time than those without. The array of organisms-including P. aeruginosa, mold, Nocardia, NTM, and CARVs-seen in BOS reflects the unique pathophysiology of this form of cGVHD, involving both systemic immunodeficiency and structural lung disease. These patterns of LRTIs and their outcomes can be used to guide clinical decisions and inform future research.

Machine Learning Algorithms to Differentiate Among Pulmonary Complications After Hematopoietic Cell Transplant.

BACKGROUND: Pulmonary complications, including infections, are highly prevalent in patients after hematopoietic cell transplantation with chronic graft-vs-host disease. These comorbid diseases can make the diagnosis of early lung graft-vs-host disease (bronchiolitis obliterans syndrome) challenging. A quantitative method to differentiate among these pulmonary diseases can address diagnostic challenges and facilitate earlier and more targeted therapy. STUDY DESIGN AND METHODS: We conducted a single-center study of 66 patients with CT chest scans analyzed with a quantitative imaging tool known as parametric response mapping. Parametric response mapping results were correlated with pulmonary function tests and clinical characteristics. Five parametric response mapping metrics were applied to K-means clustering and support vector machine models to distinguish among posttransplantation lung complications solely from quantitative output. RESULTS: Compared with parametric response mapping, spirometry showed a moderate correlation with radiographic air trapping, and total lung capacity and residual volume showed a strong correlation with radiographic lung volumes. K-means clustering analysis distinguished four unique clusters. Clusters 2 and 3 represented obstructive physiology (encompassing 81% of patients with bronchiolitis obliterans syndrome) in increasing severity (percentage air trapping 15.6% and 43.0%, respectively). Cluster 1 was dominated by normal lung, and cluster 4 was characterized by patients with parenchymal opacities. A support vector machine algorithm differentiated bronchiolitis obliterans syndrome with a specificity of 88%, sensitivity of 83%, accuracy of 86%, and an area under the receiver operating characteristic curve of 0.85. INTERPRETATION: Our machine learning models offer a quantitative approach for the identification of bronchiolitis obliterans syndrome vs other lung diseases, including late pulmonary complications after hematopoietic cell transplantation.

A Young Woman With a Rapidly Growing Thoracic Tumor.

CASE PRESENTATION: A 38-year-old woman presented with 2 months of dry cough, progressive shortness of breath, central chest pain, nausea, vomiting, and dizziness. She was previously healthy and was not taking any medications. She denied fever, night sweats, or weight loss. She had a two pack-year smoking history and had quit smoking at 27 years of age. She denied drug use and had no recent travel history. Family history was pertinent for ovarian cancer, breast cancer, and colon cancer.

Just hypercalcaemia or acute ST elevation myocardial infarction? A review of hypercalcaemia-related electrocardiographic changes.

In elderly patients presenting with confusion and recurrent falls, conditions including infection, acute stroke, acute coronary events and electrolyte abnormalities have to be strongly considered as diagnostic possibilities. ECG is a non-invasive test that often serves as a useful tool in suggesting the underlying electrolyte disturbance. However, ECG must be interpreted with caution as it can, at times, be misleading, as in this case of hypercalcaemia seen by us. We discuss the different ECG findings in hypercalcaemic situations.