Therapeutical strategies in cavitary legionnaires' disease, two cases from the field and a systematic review

BACKGROUND

Legionnaires' Disease (LD) rarely evolves into pulmonary abscesses. The current systematic review has been designed to explore therapeutical strategies in pulmonary cavitary LD.

METHODS

A research strategy was developed and applied to the databases Embase, Pubmed, and Web of Science from the 1st of January 2000 to the 1st of November 2022. Original articles, case series, case reports, and guidelines written in English, French, German, Italian, and Dutch were considered. Furthermore, medical records of patients treated at the University Hospital UZ Brussel for LD cavitary pneumonia, between the 1st of January 2016 to the 1st of January 2022, were reviewed.

RESULTS

Two patients were found by the UZ Brussel's medical records investigation. Through the literature review, 23 reports describing 29 patients, and seven guidelines were identified. The overall evidence level was low.

RESULT OF SYNTHESIS (CASE REPORTS)

The median age was 48 years and 65% were male. A polymicrobial infection was detected in 11 patients (44%) with other aerobic bacteria being the most commonly found. At diagnosis, 52% of patients received combination therapy, and fluoroquinolones were the preferred antimicrobial class. Anaerobic coverage was neglected in 33% of patients.

RESULT OF SYNTHESIS (GUIDELINES)

Three guidelines favor monotherapy with fluoroquinolones or macrolides, while one suggested an antimicrobial combination in case of severe LD. Four guidelines recommended anaerobic coverage in case of lung abscesses.

CONCLUSION

To date, the evidence supporting cavitary LD treatment is low. Monotherapy lowers toxicity and might be as effective as combination therapy. Finally, anaerobes should not be neglected.

Features of post-obstructive pneumonia in advanced lung cancer patients, a large retrospective cohort

BACKGROUND

Post-obstructive pneumonia refers to an infection of the lung parenchyma distal to a bronchial obstruction. Previous experience-based studies reported a high prevalence of this infection among patients with a medical history of advanced lung neoplasia, up to 40-55%.

OBJECTIVES

The current study was designed to investigate the features of post-obstructive pneumonia in lung cancer, including its predictors and the discriminants for 30-day mortality.

METHOD

Data from medical records at the tertiary University centre, UZ Brussel, were collected retrospectively between January 2016 and January 2021. Patients affected by lung cancer stages III and IV were included. A multidisciplinary team, composed of a pulmonologist, an infectious disease specialist and a chest radiologist, identified patients affected by post-obstructive pneumonia.

RESULTS

A total of 408 patients were included, of which 46 (11%) were diagnosed with post-obstructive pneumonia. Multivariable logistic regression for predictors of disease onset found significant differences for squamous cell carcinoma (OR:2.46 p-value: .014) and hilar location of the tumour (OR:2.72 p-value: .021). However, no significant differences were identified with regards to age or comorbidities. Furthermore, 30-day mortality among post-obstructive pneumonia patients was 30%. Multivariable logistic regression for prediction of 30-day mortality found significant differences in CURB-65 score (OR:73.20 p-value: .001) and smoking status (OR:0.009 p-value: .015).

CONCLUSIONS

Within this cohort, the prevalence of post-obstructive pneumonia in advanced lung cancer patients was lower than previously reported. Squamous cell carcinoma and a hilar tumour location were two variables associated with disease development, independent of age and comorbidities. Furthermore, a higher CURB-65 score at post-obstructive pneumonia diagnosis was correlated with mortality.

Diagnostic accuracy of screening tests for patients suspected of COVID-19, a retrospective cohort study

BACKGROUND

The diagnostic gold standard for Coronavirus-2019 disease (CoViD-19) is reverse transcriptase-polymerase chain reaction (RT-PCR). However, its sensitivity might be suboptimal. The current study aims to investigate predictive factors for false-negative nasopharyngeal RT-PCR in CoViD-19 patients. Additionally, the specificity and sensitivity of RT-PCR on the nasopharyngeal swab, serology and chest computerized-tomography (CCT) as a screening tool for the diagnosis of CoViD-19 were investigated.

METHODS

Medical records of patients admitted at the university hospital UZ Brussel during the CoViD-19 epidemic were reviewed. A group of CoViD-19 patients with false-negative RT-PCR was identified through scrupulous examination of medical records. Serological testing was performed through chemiluminescent microparticle assay.

RESULTS

Eighteen CoViD-19 patients with 'false negative' RT-PCR were identified and compared to 51 'true positives'. Logistic regression for prediction of 'false negative' RT-PCR found significantly higher serology results at hospitalization and more intensive care unit admission in the group with false-negative testing. In a cohort of 228 patients, the sensitivity of RT-PCR for the diagnosis of CoViD-19 was 85%. The sensitivity of serology was 86% and its specificity 92%. Chest computerized-tomography (CCT) showed a sensitivity of 93%, its specificity was 62%. By combining RT-PCR and serology results any 'false negative' could be excluded.

CONCLUSIONS

In this cohort, the sensitivity and specificity of RT-PCR and serology for the diagnosis of CoViD-19 were high and comparable. CCT had the highest sensitivity and confirmed its efficacy as a screening tool. CoViD-19 patients, who have a more severe presentation, might have negative RT-PCR and positive serology results.

The Value of 18F-FDG PET/CT in Predicting the Response to PD-1 Blocking Immunotherapy in Advanced NSCLC Patients with High-Level PD-L1 Expression

BACKGROUND

The objective of this study was to evaluate if ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT)-derived parameters are useful in predicting response and survival after programmed cell death protein 1 (PD-1) blocking immunotherapy in patients with advanced NSCLC characterized by a high programmed death-ligand 1 (PD-L1) expression (≥50%) on immunohistochemistry.

PATIENTS AND METHODS

In 30 patients with advanced stage IV non-small-cell lung cancer (NSCLC) and high PD-L1 expression, ¹⁸F-FDG PET/CT parameters before start of treatment with PD-1 blocking immunotherapy were evaluated retrospectively. In 24 out of the 30 patients, ¹⁸F-FDG PET/CT was available 8 to 9 weeks after start of the treatment. Response Evaluation Criteria in Solid Tumors (RECIST 1.1) and metabolic responses assessed on ¹⁸F-FDG PET/CT were compared.

RESULTS

Median follow-up was 20 months (range, 4.2-37.6). Median PD-L1 expression was 80%. The objective response rate with RECIST 1.1 was 53.3%. Median progression-free survival (PFS) was 12.4 months (95% confidence interval [CI], 1.0-37.8), and median overall survival (OS) was 14.9 months (95% CI, 2.4-38.2). Baseline ¹⁸F-FDG PET/CT parameters did not differ between responders and non-responders (all P > .05). The maximum standardized uptake value (SUVmax) was the only ¹⁸F-FDG PET/CT parameter associated with PFS (P = .04), with a trend for OS (P = .06). At first evaluation, response according to total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) were associated with PFS and OS (both P < .0001). This was not the case for RECIST 1.1 (P = .29 for PFS and P = .38 for OS).

CONCLUSION

Clinical response and survival were independent from metabolic tumor volume at baseline. Reduction of metabolic tumor volume after 8 to 9 weeks of treatment was a better predictor for prolonged survival than RECIST 1.1.

Clinical status and lung function 10 weeks after severe SARS-CoV-2 infection

INTRODUCTION

Since studies about clinical status after COVID-19 are scarce, we conducted a cross sectional study with assessment of residual symptoms, lung function and chest CT.

MATERIALS AND METHODS

During an outpatient follow-up visit, chest CT, pulmonary function and COVID-19 related symptoms were assessed approximately 10 weeks after diagnosis. Demographics, baseline (time of diagnosis) CT score and blood results were collected from patient files. Association between lung function and clinical characteristics (baseline), blood markers (baseline), chest CT (baseline and follow-up) and symptom score (followup) was analysed. Mann-Whitney U tests and Chi squared tests were used for statistical comparison between subgroups with and without restriction.

RESULTS AND DISCUSSION

Two hundred-twenty subjects were evaluated at a median follow-up of 74±12 (SD) days. Median symptom and median CT score at follow-up were 1(IQR=0- 2) and 2(IQR=0-6) respectively. Forty-six percent of patients had normal lung function, while TLC and TLCO below the lower limit of normal were observed in 38% and 22% of subjects respectively. This restrictive pulmonary impairment was associated with length of hospital stay (8 vs 6 days; p=0.003), admission to the intensive care unit (27% vs 13%;p=0.009), and invasive mechanical ventilation (10% vs 0.7%;p=0.001), but not with symptom score or CT score at baseline and follow-up.

CONCLUSIONS

Fifty-four percent of COVID-19 survivors had abnormal lung function 10 weeks after diagnosis. Restriction was the most prevalent pulmonary function, with the more critically ill patients being more prone to this condition. Yet, restriction could not be linked with abnormal imaging results or residual symptoms.

Ventilation heterogeneity in smokers: role of unequal lung expansion and peripheral lung structure

Smoking-induced ventilation heterogeneity measured at the mouth via established washout indices [lung clearance index (LCI) and alveolar mixing efficiency (AME)] potentially results from unequal expansion, which can be quantified by computer tomography (CT), and structural changes down to the lung periphery, characterized by CT parametric response mapping indices [percentage of lung affected by functional small airway disease (PRM^fSAD) and emphysema (PRM^Emph)]. By combining CT imaging and nitrogen (N₂) washout tests in smokers, we specifically examined the roles of unequal lung expansion and peripheral structure. We first extracted three-dimensional maps of local lung expansion from registered inspiratory/expiratory CT images in 50 smokers (GOLD 0-IV) to compute for each smoker the theoretical N₂ washout concentration curve solely attributable to unequal local expansion. By a head-on comparison with washout N₂ concentrations measured at the mouth in the same smokers supine, we observed that 1) LCI increased from 4.8 ± 0.2 (SD) to 6.6 ± 0.8 (SD) due to unequal lung expansion alone and further increased to 9.0 ± 1.5 (SD) independent of local expansion and 2) AME decreased (from 100% by definition) to 95 ± 2 (SD)% due to unequal expansion alone and further decreased to 75 ± 7(SD)% independent of local expansion. In a multiple regression between the washout indices and CT-derived PRM^fSAD and PRM^Emph, LCI was related to PRM^fSAD (r = +0.58; P < 0.001), whereas AME was related to both PRM^fSAD (r_partial = -0.44; P = 0.002) and PRM^Emph (r_partial = -0.31; P = 0.033), in line with AME being dominated by alterations in peripheral structure. We conclude that smokers showing an increased LCI without corresponding AME decrease are predominantly affected by unequal lung expansion, whereas an AME decrease with a commensurate LCI increase indicates a smoking-induced alteration of peripheral structure.NEW & NOTEWORTHY A head-on comparison between imaging and multiple breath washout in supine smokers shows that computer tomography-measured unequal local lung expansion accounts for 50% or less of smoking-induced increase in ventilation heterogeneity. The contributions from unequal lung expansion and peripheral structure to the two main washout indices also explain their respective association with parametric response mapping indices.

The quantitative link of lung clearance index to bronchial segments affected by bronchiectasis

In adult patients with cystic fibrosis (CF), the lung clearance index (LCI) derived from the multiple breath washout relates to both acinar and conductive ventilation heterogeneity. The latter component predicts an association between LCI and the number of bronchial segments affected by bronchiectasis. Here, we experimentally demonstrated this association in patients with CF, and also examined an ancillary group of patients with non-CF bronchiectasis. We conclude that lung disease severity in terms of number of bronchial segments results in an associated LCI increase, likely constituting a portion of LCI that cannot be reversed by treatment in patients with CF lung disease.

Pulmonary disease in cystic fibrosis: assessment with chest CT at chest radiography dose levels

PURPOSE

To investigate a computed tomographic (CT) protocol with iterative reconstruction at conventional radiography dose levels for the assessment of structural lung abnormalities in patients with cystic fibrosis ( CF cystic fibrosis ).

MATERIALS AND METHODS

In this institutional review board-approved study, 38 patients with CF cystic fibrosis (age range, 6-58 years; 21 patients <18 years and 17 patients >18 years) underwent investigative CT (at minimal exposure settings combined with iterative reconstruction) as a replacement of yearly follow-up posteroanterior chest radiography. Verbal informed consent was obtained from all patients or their parents. CT images were randomized and rated independently by two radiologists with use of the Bhalla scoring system. In addition, mosaic perfusion was evaluated. As reference, the previous available conventional chest CT scan was used. Differences in Bhalla scores were assessed with the χ(2) test and intraclass correlation coefficients ( ICC intraclass correlation coefficient s). Radiation doses for CT and radiography were assessed for adults (>18 years) and children (<18 years) separately by using technical dose descriptors and estimated effective dose. Differences in dose were assessed with the Mann-Whitney U test.

RESULTS

The median effective dose for the investigative protocol was 0.04 mSv (95% confidence interval [ CI confidence interval ]: 0.034 mSv, 0.10 mSv) for children and 0.05 mSv (95% CI confidence interval : 0.04 mSv, 0.08 mSv) for adults. These doses were much lower than those with conventional CT (median: 0.52 mSv [95% CI confidence interval : 0.31 mSv, 3.90 mSv] for children and 1.12 mSv [95% CI confidence interval : 0.57 mSv, 3.15 mSv] for adults) and of the same order of magnitude as those for conventional radiography (median: 0.012 mSv [95% CI confidence interval : 0.006 mSv, 0.022 mSv] for children and 0.012 mSv [95% CI confidence interval : 0.005 mSv, 0.031 mSv] for adults). All images were rated at least as diagnostically acceptable. Very good agreement was found in overall Bhalla score ( ICC intraclass correlation coefficient , 0.96) with regard to the severity of bronchiectasis ( ICC intraclass correlation coefficient , 0.87) and sacculations and abscesses ( ICC intraclass correlation coefficient , 0.84). Interobserver agreement was excellent ( ICC intraclass correlation coefficient , 0.86-1).

CONCLUSION

For patients with CF cystic fibrosis , a dedicated chest CT protocol can replace the two yearly follow-up chest radiographic examinations without major dose penalty and with similar diagnostic quality compared with conventional CT.

Severe right heart failure in a patient with chronic obstructive lung disease: a diagnostic challenge

A 55-year-old male was admitted for evaluation of severe dyspnoea and hypoxaemia. Physical examination upon admission showed elevated jugular venous pressure and an accentuated second heart sound. Chest radiograph showed cardiomegaly with increased bibasilar markings. Arterial blood gas analysis while breathing room air showed marked hypoxaemia. High resolution computed tomography angiography of the chest showed modestly enlarged mediastinal lymph nodes with discrete diffuse ground-glass attenuation especially at the lower lung zones. Positron emission tomography using 18F labelled 2-deoxy-D-glucose (FDG) demonstrated the mediastinal lymph nodes were FDG-avid. Transthoracic echocardiography showed dilated hypokinetic right heart chambers with bulging of the interventricular septum to the left, compatible with acute cor-pulmonale. From the tricuspid regurgitation jet measurement a systolic pulmonary artery pressure (PAP) of 48 mmHg was estimated. Patent foramen ovale was suspected on bubble test. Right heart catheterisation confirmed pulmonary arterial hypertension: mPAP 47 mmHg, pulmonary artery occlusion pressure 5 mmHg, cardiac index 1.1 L/min/m2, pulmonary vascular resistance (PVR) 959 dyne.sec.cm(-5). Pulmonary function tests showed a marked diffusing capacity for carbon monoxide (DLCO) decrease of 32% predicted but no obstructive lung deficit. Before an open lung biopsy could be scheduled the patient developed acute cardiogenic shock. At autopsy pulmonary veno-occlusive disease with marked pulmonary hypertension was diagnosed.

Spontaneous soccer-induced pneumomediastinum in a 39-year-old man

We report on a healthy 39-year-old man who developed spontaneous pneumomediastinum during a soccer game without a traumatic impact. Chest radiography and CT demonstrated the extensive pneumomediastinum and subcutaneous emphysema. Treatment of this rare condition is conservative and prognosis is excellent.

Occurrence of pulmonary artery aneurysms and pulmonary artery thrombosis in a young man

Behçet's disease (BD) is a multisystemic inflammatory disorder of unknown aetiology. Arterial involvement is uncommon but associated with important morbidity and mortality. We describe the clinical course of BD with severe pulmonary artery involvement in a 19-year-old man. He presented with massive haemoptysis related to pulmonary artery aneurysms. Initial treatment consisted in urgent right inferior lobectomy, corticosteroids and monthly intravenous cyclophosphamide. Subsequently, he developed pulmonary artery thrombosis at non-aneurysmatic sites. Corticosteroid therapy was intensified, monthly intravenous cyclophosphamide was continued and an anticoagulant was added to the treatment with a favourable clinical and radiological response. Our case illustrates that timely initiation of highly potent immunosuppressive therapy is critical to obtain a favourable outcome. At present, a consensus regarding optimal management of vascular BD is lacking. ALthough anticoagulation is not generally recommended, our report encourages a patient-based decision after carefully tailoring potential risks and benefits.

Spontaneous intrahepatic gas gangrene and fatal septic shock

Gas gangrene of the liver is a rare clinical syndrome associated with a high rate of mortality. It is mostly associated with malignancy and immunosuppression. We report on a male patient who presented at the department of emergency medicine with high fever but no localised complaints. CT scan revealed a cavitary lesion filled with air in the liver. Clostridium perfringens was proved to be present in the hepatic lesion and the blood, and clostridium perfringens sepsis with gas gangrene of the liver was diagnosed. Despite early diagnosis and treatment the patient died. The importance of "an aggressive treatment policy" in this kind of life-threatening disease is emphasised.

Indications for body MRI Part II: retroperitoneum, intestines and pelvis

In this article an overview is given of the present knowledge of whole body MRI, MRI of the retroperitoneum, intestines and pelvis. Recommendations are based on current literature and clinical applications in daily routine focusing on efficacy rather than cost considerations. The contribution and complementary role of MRI relative to those of its competing modalities was the most important endpoint assessed. Perfusion and functional information, as well as specific contrast agents in the area of the pelvis are still considered research indications.

Radiofrequency ablation of the liver: how do we do it

Radiofrequency ablation is a minimally invasive cancer treatment used as an alternative for unresectable hepatic malignancies. Tumor ablation implies direct application of thermal or chemical therapies on a specific focal tumor. The aim of radiofrequency ablation is a total eradication of the tumor or at least a substantial tumor destruction. The thermal energy can be heat (radiofrequency, laser, microwave,...) or cold (cryoablation).