Siddhartha G. Kapnadak

Infection control strategies that successfully controlled an outbreak of Mycobacterium abscessus at a cystic fibrosis center

BACKGROUND Mycobacterium abscessus infection in patients with cystic fibrosis (CF) can result in accelerated clinical decline and the potential for direct or indirect transmission between patients has been recently demonstrated. Data on the outcomes of M abscessus outbreaks and the efficacy of specific infection control procedures in patients with CF remain limited. This study provides follow-up from an outbreak of pulmonary M abscessus in our center, highlighting outcomes and strategies that appear to have prevented further spread of the organism. METHODS Data from our adult CF center (1989-2015) were analyzed, including chart reviews of all patients with positive mycobacterial sputum cultures, cultures from environment surfaces, and epidemiologic evaluation of infected patients. Following an M abscessus outbreak in 2009, infection control policies were intensified based on CF guidelines and surveillance data were collected and reviewed. RESULTS Five cases of M abscessus were involved in the outbreak; 3 patients died during follow-up. An environment search failed to reveal an intermediary source of transmission between patients. After implementation of infection control measures composed of staff/patient education, environment sterilization, and patient isolation, no new cases were detected. CONCLUSIONS Direct or indirect patient-to-patient transmission of M abscessus is a threat in the CF population. A multifaceted infection control strategy based on CF guidelines was effective in halting transmission in our center.

Clinical outcomes associated with high, intermediate, and low rates of failed extubation in an intensive care unit

PURPOSE Extubation failure is associated with adverse outcomes in mechanically ventilated patients, and it is believed that high rates of failed planned extubation (FPE) should be avoided. However, many believe that very low rates may also correlate with adverse outcomes if resulting from overly conservative weaning practices. We examined the relationship between the percentage of FPE (%FPE) and associated outcomes, with the aim of elucidating a favorable middle range. METHODS A total of 1395 extubations were analyzed in mechanically ventilated subjects. Monthly %FPE values were separated into tertiles. Ventilator-free days (VFDs), intensive care unit-free days (IFDs), and mortality were compared among tertiles. RESULTS Monthly %FPE tertiles were as follows: low, less than 7%; intermediate, 7% to 15%; and high, greater than 15%. There were significant differences in VFDs and IFDs by tertile from low to high (VFDs: low, 11.8; intermediate, 12.1; high, 9.9 [P = .003]; IFDs: low, 10.5; intermediate, 10.7; high, 9.0 [P = .033]). Post hoc comparisons demonstrated significant differences between the middle and high tertiles for both VFDs and IFDs. CONCLUSIONS Although exact rates may vary depending on setting, this suggests that a high %FPE (>15) should be avoided in the intensive care unit and that there may be an intermediate range where ventilator outcomes are optimized.

Lung transplantation in idiopathic pulmonary fibrosis

ABSTRACT Introduction: Idiopathic Pulmonary Fibrosis (IPF) is a unique type of interstitial pneumonia in which progressive fibrosis can ultimately result in respiratory failure and death. The median survival of IPF remains dismal despite newer anti-fibrotic therapies. Lung transplantation is the only modality currently known to enhance survival for patients with IPF. Areas covered: Since IPF is predominantly a disorder of the elderly, determination of the impact of co-morbidities is crucial for risk stratification of the individual patient. We review the potential effect of anti-fibrotic therapy in the pre and post-transplant period; and also discuss the factors that need to be considered in deciding between single lung and bilateral lung transplantation. Expert commentary: Early referral to a transplant center is recommended for patients with IPF due to the high waiting list mortality. Evaluation of the transplant candidate should also be directed specifically at identifying co-morbidities that portend higher risk. While there has been a universal trend favoring bilateral lung transplantation over single lung transplantation for IPF, there are inherent pros and cons for both strategies and decisions should be individualized. Further studies are required to deduce the efficacy and safety of anti-fibrotic drugs in the immediate pre-and post-lung transplantation period.

Common clinical features of CF (respiratory disease and exocrine pancreatic insufficiency)

First described as a disease of the pancreas, cystic fibrosis is a genetically inherited progressive disease affecting multiple organ systems. Pulmonary and pancreatic involvement is common in individuals with cystic fibrosis, and the former is attributable to most of the mortality that occurs with the condition. This chapter provides an overview of a clinical approach to the pulmonary and pancreatic manifestations of cystic fibrosis.

Tracheal diverticula in advanced cystic fibrosis: Prevalence, features, and outcomes after lung transplantation

BACKGROUND Tracheal diverticula (TD) are rare anomalies that may harbor infected secretions, posing potential risk to patients with lung disease. In an end-stage cystic fibrosis (CF) cohort, we describe the characteristics and associated post-lung transplant (LTx) outcomes of TD. METHODS Pre-transplant computed tomography (CT)s were reviewed in CF patients undergoing LTx. TD were characterized radiographically and on autopsy when available. Pre-transplant clinical variables and post-transplant outcomes were compared by TD status. RESULTS Of 93 patients, 35 (37.6%) had TD. 58% of TD had fat-stranding, and post-mortem TD examinations revealed histology carrying intense submucosal inflammation, and purulent contents that cultured identical species to sputum. There was no difference in post-LTx survival [HR 1.77 (0.82-3.82), p=0.147], bacterial re-colonization, or rejection in patients with TD compared to those without. Patients with TD were more likely to die from infection, but the result was not statistically significant [HR 2.02 (0.62-6.63), p=0.245]. CONCLUSIONS We found a high prevalence of TD in end-stage CF, where diverticula may represent a large-airway bacterial reservoir. TD were not associated with differences in post-LTx outcomes, but given the infectious concerns further investigation is necessary.

A 21-Year-Old Woman With Cystic Fibrosis, Abdominal Pain, and Recent Weight Loss

A 21-year-old woman with cystic fibrosis (CF) was seen in the pulmonary clinic complaining of abdominal pain. Her past medical history included bilateral lung transplantation for CF pulmonary disease 26 months previously, as well as gastroesophageal reflux disease and pancreatic insufficiency. Her baseline weight was 49.1 kg (BMI, 19.4 kg/m2).

Imaging of Lung Transplantation

Lung transplantation has become a viable treatment option for end-stage lung disease. Common indications for lung transplantation are chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis, cystic fibrosis, alpha-1 antitrypsin deficiency, and pulmonary arterial hypertension. Either single or bilateral lung transplantation can be performed, but bilateral lung recipients appear to have a better median survival than single lung recipients. Complications after lung transplantation are common and may have nonspecific clinical and radiologic manifestations. The time point at which these complications occur relative to the date of transplant is crucial in formulating a differential diagnosis and recognizing them accurately. Significant advances in imaging techniques and recognition of air trapping in exhalation images and other patterns /distribution of parenchymal abnormalities have led to routine use of HRCT for diagnostic evaluation in patients manifesting respiratory decline in the lung transplant recipient.

Radiologic computed tomography features of Mycobacterium abscessus in cystic fibrosis.

Mycobacterium abscessus infection in cystic fibrosis (CF) patients can lead to poor outcomes. Early diagnosis is important, but there are no studies outlining specific imaging features of M. abscessus in CF.

An Unusual Cause of Pulmonary Nodules After Stem Cell Transplantation

&NA; A man in his 20s with a history of classical Hodgkins lymphoma was admitted with fever. His original lymphoma diagnosis was made 3 years prior, when he had presented with lymphadenopathy and a mediastinal mass. He had relapsed disease despite chemotherapy and radiation. As a result, he underwent autologous peripheral blood stem cell transplant (SCT) 6 months prior to current presentation and subsequently allogeneic SCT 2 months prior for added graft vs tumor effect.

A middle rate of failed extubation is desirable?: Questions unanswered (reply).

We have read the research by Kapnadak et al [1] with great interest. In this article, the authors evaluate the differences in clinical outcomes relative to a high, intermediate, or low percentage of failed planned extubation. They describe that the best percentage of failed planned extubation is located in the intermediate range (7%-15%) because, in this range, more ventilator-free days and intensive care unit–free days are observed. Furthermore, no significant difference was found in secondary outcome mortality. In this way, we have some questions. Prolongedweaning is defined as the process that requiredmore than 7 days from the first attempt at withdrawal of mechanical ventilation until extubation, as described by Penuelas [2] and Sellares [3]. This prolonged weaning is associated with a higher rate of failed extubation compared with simple or difficult weaning [2,3]. Therefore, the authors should specify the type of weaning in each subgroup because this could affect the results. Furthermore, the study did not specify the period of mechanical ventilation according to tertile distribution. It is necessary to know this information because an association between prolongedmechanical ventilation and extubation failure has been described [4,5].