Decreased plasma cartilage acidic protein 1 in COVID-19.

Cartilage acidic protein-1 (CRTAC1) is produced by several cell types, including Type 2 alveolar epithelial (T2AE) cells that are targeted by SARS-CoV2. Plasma CRTAC1 is known based on proteomic surveys to be low in patients with severe COVID-19. Using an ELISA, we found that patients treated for COVID-19 in an ICU almost uniformly had plasma concentrations of CRTAC1 below those of healthy controls. Magnitude of decrease in CRTAC1 distinguished COVID-19 from other causes of acute respiratory decompensation and correlated with established metrics of COVID-19 severity. CRTAC1 concentrations below those of controls were found in some patients a year after hospitalization with COVID-19, long COVID after less severe COVID-19, or chronic obstructive pulmonary disease. Decreases in CRTAC1 in severe COVID-19 correlated (r = 0.37, p = 0.0001) with decreases in CFP (properdin), which interacts with CRTAC1. Thus, decreases of CRTAC1 associated with severe COVID-19 may result from loss of production by T2AE cells or co-depletion with CFP. Determination of significance of and reasons behind decreased CRTAC1 concentration in a subset of patients with long COVID will require analysis of roles of preexisting lung disease, impact of prior acute COVID-19, age, and other confounding variables in a larger number of patients.

Outcomes of prednisone-tapering regimens for cardiac sarcoidosis: A retrospective analysis demonstrating a benefit of infliximab.

BACKGROUND: The optimal treatment strategy for cardiac sarcoidosis has not been standardized. We examined the effectiveness of three prednisone-tapering treatment regimens for cardiac sarcoidosis. METHODS: We retrospectively reviewed prednisone-tapering treatment regimens for cardiac sarcoidosis that contained prednisone alone (P), prednisone plus methotrexate (P-M), and prednisone plus infliximab containing regimens (P-I). We defined the success of each regimen as the ability to lower the daily prednisone dose to 7.5 mg or less for 6 or more months without developing an adverse cardiac event. We also examined the lowest effective daily prednisone dose achieved without developing an adverse cardiac event. RESULTS: We identified 61 treatment regimens in 33 cardiac sarcoidosis patients that were analyzed. The success rate of prednisone-tapering regimens was significantly different P: 8/30, 27%; P-M: 3/23, 13%; P-I: 6/8, 75%., p = 0.04. The lowest effective daily prednisone dose for the regimens was also significantly different: P: 14.1 ± 10.1 mg; P-M: 16.9 ± 9.4 mg; infliximab: 7.8 ± 4.9 mg, (p = 0.03); by both measures the success was greatest with the P-I regimen. CONCLUSIONS: For the treatment of cardiac sarcoidosis, prednisone-tapering regimens containing infliximab are superior to those containing prednisone alone or prednisone plus methotrexate in terms of reaching 7.5 mg/day of prednisone for more than 6 months and achieving the lowest effective prednisone.

Persistent blood DNA methylation changes one year after SARS-CoV-2 infection.

We recently reported the COVID-19-induced circulating leukocytes DNA methylation profile. Here, we hypothesized that some of these genes would persist differentially methylated after disease resolution. Fifteen participants previously hospitalized for SARS-CoV-2 infection were epityped one year after discharge. Of the 1505 acute illness-induced differentially methylated regions (DMRs) previously identified, we found 71 regions with persisted differentially methylated, with an average of 7 serial CpG positions per DMR. Sixty-four DMRs persisted hypermethylated, and 7 DMR persisted hypomethylated. These data are the first reported evidence that DNA methylation changes in circulating leukocytes endure long after recovery from acute illness.

The association of baseline sarcoidosis measurements with 6-month outcomes that are of interest to patients: Results from the On-line Sarcoidosis Assessment Platform Study (OSAP).

INTRODUCTION: The impact of common measures to assess sarcoidosis have not been compared longitudinally to outcomes that are meaningful to patients. We prospectively examined the relationship of baseline measurements of sarcoidosis status to outcomes of interest to patients longitudinally over 6 months. METHODS: Sarcoidosis patients cared for at 6 US medical centers were "phenotyped" at baseline with measurements of pulmonary function, organ involvement, health related quality of life (HRQoL) instruments, and their anti-sarcoidosis treatment history. These patients were followed for 6 months by monitoring outcomes of interest to patients (OIPs) including steps walked, calories expended, sleep, HRQoL measures, workdays missed and health care utilization. For each baseline phenotypic measurement, patients were dichotomized into two groups above and below a specified cutoff value. The area under the OIP versus time curve was compared between these two groups. RESULTS: The cutoff values for many baseline phenotypic measures distinguished the patients into groups with significantly different 6-month OIPs. The chosen cutoff for the patient global estimate of health status distinguished the most OIPs (13/15). The 6-min walk distance cutoff was associated with more OIPs than spirometric measures. All of the HRQOL measure cutoffs were associated with many OIPs, although most of them were other HRQOL measures. INTERPRETATION: Cutoffs for most of the phenotypic measures used to assess sarcoidosis distinguished groups of sarcoidosis patients with differing OIPs over the subsequent 6 months. The patients' global assessment of their disease was the most accurate of these measures. CLINICAL TRIAL REGISTRATION NUMBER: NCT04342403.

Association between Drainage-Dependent Prolonged Air Leak after Partial Lung Resection and Clinical Outcomes: A Prospective Cohort Study.

Rationale: Prolonged air leak (PAL) after partial lung resection can occur owing to surgical complications or in the presence of residual thoracic space. The former type results in drainage-independent PAL (DIPAL), whereas the latter type results in drainage-dependent PAL (DDPAL). DDPAL is described after thoracentesis in patients with nonexpandable lung, where the thoracostomy tube can be discontinued safely despite an ongoing air leak. This distinction is clinically relevant, as in the presence of DDPAL, tube thoracostomy can be safely discontinued without the need for further interventions. Objectives: To determine the frequency and clinical relevance of DDAPL and DIPAL in patients with PAL after partial lung resection. Methods: We prospectively identified consecutive patients with PAL after partial lung resection. Pleural manometry was performed 3-5 days after surgery. Pleural pressure was measured for 20 minutes after clamping the thoracostomy tube. DDPAL was diagnosed if the end-expiratory pleural pressure remained stable after plateauing in the absence of respiratory symptoms. Results: Of 225 patients who underwent lung resection, we identified 22 (10%) who had PAL. Twenty patients had adequate pleural manometry readings. The majority, 16/20 (80%), had DDPAL and had lower median hospital length of stay than those with DIPAL (6.9 vs. 11 days; P = 0.02). All patients with DIPAL required reexploration surgery, whereas only one patient with DDPAL underwent reexploration surgery. Conclusions: Most PALs after partial lung resection are DDPAL. Patients with DDPAL have lower hospital length of stay and less need for reexploration surgery than those with DIPAL.

Pneumothorax in critically ill patients with COVID-19 infection: Incidence, clinical characteristics and outcomes in a case control multicenter study.

BACKGROUND: The clinical features and outcomes of mechanically ventilated patients with COVID-19 infection who develop a pneumothorax has not been rigorously described or compared to those who do not develop a pneumothorax. PURPOSE: To determine the incidence, clinical characteristics, and outcomes of critically ill patients with COVID-19 infection who developed pneumothorax. In addition, we compared the clinical characteristics and outcomes of mechanically ventilated patients who developed a pneumothorax with those who did not develop a pneumothorax. METHODS: This study was a multicenter retrospective analysis of all adult critically ill patients with COVID-19 infection who were admitted to intensive care units in 4 tertiary care centers in the United States. RESULTS: A total of 842 critically ill patients with COVID-19 infection were analyzed, out of which 594 (71%) were mechanically ventilated. The overall incidence of pneumothorax was 85/842 (10%), and 80/594 (13%) in those who were mechanically ventilated. As compared to mechanically ventilated patients in the non-pneumothorax group, mechanically ventilated patients in the pneumothorax group had worse respiratory parameters at the time of intubation (mean PaO2:FiO2 ratio 105 vs 150, P<0.001 and static respiratory system compliance: 30ml/cmH2O vs 39ml/cmH2O, P = 0.01) and significantly higher in-hospital mortality (63% vs 49%, P = 0.04). CONCLUSION: The overall incidence of pneumothorax in mechanically ventilated patients with COVID-19 infection was 13%. Mechanically ventilated patients with COVID-19 infection who developed pneumothorax had worse gas exchange and respiratory mechanics at the time of intubation and had a higher mortality compared to those who did not develop pneumothorax.

Novel ACE mutations mimicking sarcoidosis by increasing blood ACE levels.

An elevated blood angiotensin I-converting enzyme (ACE) supports diagnosis of sarcoidosis and Gaucher disease. However, some ACE mutations increase ACE shedding, and patients with these mutations are therefore at risk of being incorrectly diagnosed with sarcoidosis because of elevated serum ACE levels. We applied a novel approach called "ACE phenotyping" to identify possible ACE mutations in 3 pulmonary clinic patients that had suspected sarcoidosis based on elevated blood ACE levels. Conformational fingerprinting of ACE indicated that these mutations may be localized in the stalk region of the protein and these were confirmed by whole exome sequencing. Index patient 1 (IP1) had a mutation (P1199L) that had been previously identified, while the other 2 patients had novel ACE mutations. IP2 had 2 mutations, T887M and N1196K (eliminating a putative glycosylation site), while IP3 had a stop codon mutation Q1124X (eliminating the transmembrane anchor). We also performed a comprehensive analysis of the existing database of all ACE mutations to estimate the proportion of mutations increasing ACE shedding. The frequency of ACE mutations resulting in increased blood ACE levels may be much higher than previously estimated. ACE phenotyping, together with whole exome sequencing, is a diagnostic approach that could prevent unnecessary invasive and/or costly diagnostic procedures, or potentially harmful treatment for patients misdiagnosed on the basis of elevated blood ACE levels.