A retrospective record review of tuberculous infections in rheumatoid arthritis patients on biologics in Malaysia.

INTRODUCTION: The aim of this study was to analyse the clinical characteristics of patients with rheumatoid arthritis receiving biologics therapy and investigate the association between types of biologics and tuberculosis (TB) infections in 13 tertiary hospitals in Malaysia. MATERIALS AND METHODS: This was a retrospective study that included all RA patients receiving biologics therapy in 13 tertiary hospitals in Malaysia from January 2008 to December 2018. RESULTS: We had 735 RA patients who received biologics therapy. Twenty-one of the 735 patients were diagnosed with TB infection after treatment with biologics. The calculated prevalence of TB infection in RA patients treated with biologics was 2.9% (29 per 1000 patients). Four groups of biologics were used in our patient cohort: monoclonal TNF inhibitors, etanercept, tocilizumab, and rituximab, with monoclonal TNF inhibitors being the most commonly used biologic. The median duration of biologics therapy before the diagnosis of TB was 8 months. 75% of patients had at least one co-morbidity and all patients had at least one ongoing cDMARD therapy at the time of TB diagnosis. More than half of the patients were on steroid therapy with an average prednisolone dose of 5 mg daily. CONCLUSION: Although the study population and data were limited, this study illustrates the spectrum of TB infections in RA patients receiving biologics and potential risk factors associated with biologics therapy in Malaysia.

Neuropsychiatric Side Effects After Lumbosacral Epidural Steroid Injections: A Prospective Cohort Study.

BACKGROUND: The central nervous system contains steroid receptors, particularly in the hypothalamic and limbic systems. These systems are responsible for driving certain emotions in humans, especially stress, anxiety, motivation, energy levels, and mood. Thus, corticosteroids may precipitate patients to experience these emotions. Most existing studies report neuropsychiatric side effects after oral or intravenous corticosteroids rather than epidural. OBJECTIVES: This study examines the neuropsychiatric side effects after epidural steroid injections (ESIs), with a focus on whether certain factors in patients' histories further exacerbate symptomatology. STUDY DESIGN: Prospective observational cohort study. SETTING: Fluoroscopy suite at an urban academic teaching hospital. METHODS: Patients were called 24 hours and one week after their ESIs and asked if they experienced certain neuropsychiatric symptoms more than usual compared to baseline. PATIENTS: Seventy-four patients undergoing a lumbosacral ESI (interlaminar (ILESI), caudal or transforaminal (TFESI)) were invited to take part in the study the day of his or her procedure. INTERVENTION/MEASUREMENT: Assessed whether psychiatric history, gender, race, type of ESI, or the number of levels injected affected frequency and duration of neuropsychiatric symptoms at one day and one week after an ESI. RESULTS: Significantly (P < 0.05) more patients with a psychiatric history experienced restlessness and irritability at day one than those without a psychiatric history. At week one, male gender (IRR 2.29, 95% CI 1.37, 3.83, P = 0.002), ILESI (IRR 7.75, 95% CI 1.03, 58.6, P = 0.047), and 2-level injections (IRR 2.14, 95% CI 1.13, 4.06, P = 0.019) were significantly associated to more total symptoms. LIMITATIONS: Single center study, reliance on subjective responses from patients, lack of follow-up after one week post-ESI. CONCLUSION(S): This study demonstrates that neuropsychiatric symptoms are rare overall after an ESI, though certain factors may influence patients experiencing these symptoms. Restlessness and irritability were more likely to occur one day after an ESI in those with a psychiatric history. Those who had a 2-level injection were more likely to keep experiencing most symptoms by week one, suggesting a possible correlation between corticosteroid dose and neuropsychiatric symptoms.

Impact of Body Mass Index on Opioid Prescriptions Following Lumbar Spine Surgery.

OBJECTIVE: This study aimed to evaluate the association between BMI and postoperative opioid use within two years following lumbar spine surgery using a national database. METHODS: TriNetX, a national network of de-identified patient records, was retrospectively queried from 2003 to 2021 using ICD-10, CPT, and VA codes. Propensity-score matching analysis was performed based on demographics, comorbidities, anxiety disorders, and mood disorders. RESULTS: 21,997 total patients were included in our analysis. Patients with BMI > 30 were more likely to be prescribed opioids postoperatively (OR: 1.30; 95% CI: 1.18-1.42). Patients with BMI > 40 were more likely to be prescribed opioids when compared to patients with BMI < 30 (OR: 1.94; 95% CI: 1.48-2.56), BMI 30-34.9 (OR: 2.06; 95% CI: 1.57-2.70), BMI 35-39.9 (OR: 1.50; 95% CI: 1.13-2.00), and BMI < 40 (OR: 2.06; 95% CI: 1.57-2.70). The BMI > 40 group had an increased number of opioid prescriptions within two years following lumbar surgery compared to patients with BMI 30-34.9 (p = 0.0113) and BMI < 30 (p = 0.0018). CONCLUSION: Opioid prescription following lumbar spine surgery is associated with an elevated BMI. Patients with Class III Obesity appear to be at the highest risk of increased opioid prescriptions following lumbar surgery. Physicians should consider the patient's BMI when deciding postoperative pain management.

Case Report: Focal, generalized, or both: does generalized network involvement preclude successful epilepsy surgery?

We present two cases with focal seizures where scalp electroencephalography (EEG) had prominent features of a developmental and epileptic encephalopathy (DEE): Case 1: a 17-year-old male with complex motor seizures whose EEG demonstrated a slow spike-and-wave pattern and generalized paroxysmal fast activity (GPFA). Case 2: a 12-year-old male with startle-induced asymmetric tonic seizures whose EEG also had a slow spike-and-wave pattern. Both patients had intracranial EEG assessment, and focal cortical resections resulted in long-term seizure freedom and resolution of generalized findings. These cases exemplify patients with focal epilepsy with networks that share similarities to generalized epilepsies, and importantly, these features did not preclude curative epilepsy surgery.

Incidence of Sacroiliac Joint Pain Following Lumbar Fractures: A Retrospective-Cohort Study.

BACKGROUND: Sacroiliac joint (SIJ) pain commonly affects patients with low back pain and can arise from traumatic and degenerative causes. However, the incidence of SIJ pain following lumbar fractures is not well understood. METHODS: TriNetX, a national network of deidentified patient records, was retrospectively queried. The lumbar fracture cohort included 239,199 adults, while the no lumbar fracture group included 6,975,046 adults. Following a propensity-score match based on demographics and risk factors for SIJ, there were 239,197 patients in each cohort. The incidence of SIJ pain and clinical outcomes were analyzed from 1 day to 1 year following the index event. Moreover, the location and type of single-level lumbar fractures were reported. The incidence of SIJ pain for single-level fractures was compared using a χ2 goodness-of-fit. RESULTS: The lumbar fracture cohort was more likely to develop SIJ pain at 3 months (odds ratio [OR]: 5.3, 95% confidence interval [CI]: 4.8-5.9), 6 months (OR: 4.4, 95% CI: 4.1-4.8), and 1 year (OR: 3.9, 95% CI: 3.6-4.2) postfracture. Among single-level lumbar fractures, the incidence of SIJ pain at 1 month (P = 0.005), 6 months (P = 0.010), and 1 year (P = 0.003) varied significantly, with the highest incidence in the L5 cohort. CONCLUSIONS: Our findings suggest that lumbar fractures are a risk factor for developing SIJ pain. Moreover, the incidence of SIJ pain is greater following an L5 fracture than an L1 fracture. Further investigation is warranted to determine how the type and treatment of lumbar fractures affects the incidence of SIJ pain.

The network is more important than the node: stereo-EEG evidence of neurocognitive networks in epilepsy.

Introduction: Neuropsychological assessment forms an integral part of the presurgical evaluation for patients with medically refractory focal epilepsy. Our understanding of cognitive impairment in epilepsy is based on seminal lesional studies that have demonstrated important structure-function relationships within the brain. However, a growing body of literature demonstrating heterogeneity in the cognitive profiles of patients with focal epilepsy (e.g., temporal lobe epilepsy; TLE) has led researchers to speculate that cognition may be impacted by regions outside the seizure onset zone, such as those involved in the interictal or "irritative" network. Methods: Neuropsychological data from 48 patients who underwent stereoelectroencephalography (SEEG) monitoring between 2012 and 2023 were reviewed. Patients were categorized based on the site of seizure onset, as well as their irritative network, to determine the impact of wider network activity on cognition. Neuropsychological data were compared with normative standards (i.e., z = 0), and between groups. Results: There were very few distinguishing cognitive features between patients when categorized based purely on the seizure onset zone (i.e., frontal lobe vs. temporal lobe epilepsy). In contrast, patients with localized irritative networks (i.e., frontal or temporal interictal epileptiform discharges [IEDs]) demonstrated more circumscribed profiles of impairment compared with those demonstrating wider irritative networks (i.e., frontotemporal IEDs). Furthermore, the directionality of propagation within the irritative network was found to influence the manifestations of cognitive impairment. Discussion: The findings suggest that neuropsychological assessment is sensitive to network activity beyond the site of seizure onset. As such, an overly focal interpretation may not accurately reflect the distribution of the underlying pathology. This has important implications for presurgical work-up in epilepsy, as well as subsequent surgical outcomes.

Radiological Criteria for Acceptable Alignment in Paediatric Mid-Shaft Forearm Fractures: A Systematic Review.

Introduction: Forearm fractures are common in children. The remodelling capacity of growing long bones in children makes these potentially forgiving injuries, recovering with good outcomes despite minimal intervention. Clinicians rely on radiological characteristics that vary with age to guide treatment decisions and minimise adverse sequelae. The purpose of this review was to consolidate the evidence base of radiological indications for intervention in paediatric mid-shaft forearm fractures. Materials and methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed for this review. Citable research output reporting radiological criteria for mid-shaft forearm fractures in paediatric patients (age ≤16 years) was screened and analysed to ascertain acceptable radiological criteria for non-operative management. Results: A total of 2,059 papers were initially identified; 14 were selected following screening. Sagittal angulation >15°, coronal angulation >10°, and/or >50% (or >1cm) translation were the most common radiological indications for intervention in children aged 0 to 10 years. For children over 10 years of age, the most common radiological indication for intervention was sagittal angulation >10°, coronal angulation >10°, and/or >50% (or >1cm) translation. Conclusion: This study revealed a scarcity of high-quality evidence to guide management and significant variation in outcome reporting throughout the published literature. Since Noonan and Price's 1998 recommendations, there has been no significant evolution in the evidence-base guided threshold for intervention in paediatric mid-shaft forearm fractures. There remains a pressing need for a robust multicentre observational study using the patient-reported outcome measurement information system (PROMIS) to address this complex and controversial area of uncertainty in paediatric trauma management.

Lung Cancer Screening with Low-Dose Helical CT in Korea: Experiences at the Samsung Medical Center

To determine overall detection rates of lung cancer by low-dose CT (LDCT) screening and to compare histopathologic and imaging differences of detected cancers between high- and low-risk groups, this study included 6,406 asymptomatic Korean adults with >or=45 yr of age who underwent LDCT for lung cancer screening. All were classified into high- (>or=20 pack-year smoking; 3,353) and low-risk (3,053; <20 pack-yr smoking and non-smokers) groups. We compared CT findings of detected cancers and detection rates between high- and low-risk. At initial CT, 35% (2,255 of 6,406) had at least one or more non-calcified nodule. Lung cancer detection rates were 0.36% (23 of 6,406). Twenty-one non-small cell lung cancers appeared as solid (n=14) or ground-glass opacity (GGO) (n=7) nodules. Cancer likelihood was higher in GGO nodules than in solid nodules (p<0.01). Fifteen of 23 cancers occurred in high-risk group and 8 in low-risk group (p=0.215). Therefore, LDCT screening help detect early stage of lung cancer in asymptomatic Korean population with detection rate of 0.36% on a population basis and may be useful for discovering early lung cancer in low-risk group as well as in high-risk group.

Clinical investigation of lipoid pneumonia in adults / 결핵

Background: Exogenous lipoid pneumonia is caused by inhalation or aspiration of animal, vegetable or mineral oil. Most cases are ascribed to aspiration of oil in laxatives or nose drops Petroleum, another pure hydrocarbon used as a base in various medications, is occasionally involved. Especially animal oil produces severe tissue inflammatory reaction, but most patients present with only abnormal chest X-ray and no specific clinical symptoms or signs. Method: Seven patients, 3 males and 4 females, with exogenous lipoid pneumonia, who was hospitalized or referred to pulmonary division at Samsung Medical Center from December 1994 to July 1996, were included. They hadn a history of taking shark liver oil(so-called "squalene") for varying period of time. We reviewed clinical, radioloic and pathologic findings. Result: Patients took 7 to 30 capsules of "squalene" a day for at least one month to 5 years. Six cases had chronic disease such as diabetes, hypertension, or cerebrovascular accident. Respiratory symptoms of mild fever, cough and sputum were present in 3 cases and in 3 cases there was no clinical symptoms and signs but abnormal findings by chest X-ray. The major radiologic findings by simple chest X-ray and computed tomography consisted of consolidation, infiltration involving mainly right middle and both lower lobes, and ground-glass opacity. Five of six bronchoscopic examinations demonstrated both lipid droplets floating on the surface of bronchoalveolar lavage fluid and lipid-laden macrophages in bronchoalveolar lavage fluid or lung tissue. Follow-up chest X-ray showed improvement in 4 cases but no marked interval change in 3 cases after removal of exposure to "squalene". Conclusion: Shark liver oil can induce lipoid pneumonia in adults. In case of high clinical suspicion, confirmation of "squalene" use by careful history taking is required and bronchoscopy is helpful in diagnosis.

Malignant and Benign Diffuse Pleural Disease: Utility of FDG PET in Differential Diagnosis and Comparison with CT

PURPOSE: To assess the utility of 2-[18F] fluoro-2-deoxy-D-glucose (FDG) PET in differentiating malignant and benign diffuse pleural disease, and to compare it with CT. MATERIALS AND METHODS: Both FDG PET and CT scans were performed in 20 consecutive patients with diffuse pleural disease (13 malignant and seven benign cases). In FDG PET, peak standardized uptake value (SUV) as well as visual assessment of abnormally increased uptake in the pleura was evaluated. The results were compared with CT findings. RESULTS: With only visual assessment of PET images, sensitivity, specificity, and accuracy for malignancy were 92%, 43%, and 75%, respectively. With peak SUV of 4.8 or more, the corresponding figures were 100%, 57%, and 85%, respectively, and on CT interpretation, were100%, 57%, and 85%, respectively. Tuberculous empyema simulated malignant pleural disease both on FDG PET (3/6 patients with peak SUV more than 4.8) and CT (3/6 patients). CONCLUSION: For the differentiation of malignant and benign diffuse pleural disease, FDG PET and CT are equally accurate. Combined visual and quantitative assessments of PET images enhance discriminatory ability. Tuberculous empyema simulates malignant pleural disease both on FDG PET and CT.

A case of pulmonary diffuse alveolar amyloidosis localized in the lung / 대한내과학회지

Primary pulmonary diffuse alveolar amyloidosis is a rare form among the pulmonary amyloidosis. Especially in primary form diffuse alveolar type is much more rare disease. the patient was checked simple chest X-ray for the purpose of routine screening test, he had no respiratory symptoms and signs and he had no complaint of other organ symptoms, while in chest roentgenogram it was found bilateral diffuse interstitial infiltration of the lung, but any other organs which commonly involved in amyloidosis were not involved in laboratory and other specific diagnostic procedures. We report a case of pulmonry diffuse alveolar amyloidosis only localized in lung which was confirmed by transbronchial lung biopsy.

Difference in Patient's Work of Breathing Between Pressure-Controlled Ventilation with Deccelerating Flow and Volume-Controlled Ventilation with Constant Flow during Assited Ventilation / 결핵

BACKGROUND: The patient's work of breathing(WOBp) during assisted ventilation may vary according to many factors including ventilatory demand of the patients and applied ventilatory setting by the physician. Pressure-controlled ventilation(PCV) which delivers gas with decelerating flow may better meet patients' demand to improve patientventilator synchrony compared with volume-controlled ventilation(VCV) with constant flow. This study was conducted to compare the difference in WOBp in two assisted modes of ventilation, PCV and VCV with constant flow. METHODS: Ten patients with respiratory failure were included in this study. Initially, the patients were placed on VCV with constant flow at low tidal volume(VT,LOW)(6-8 ml/kg) or high tidal volume(VT,HIGH)(10-12 ml/kg). After a 15 minute stabilization period, VCV with constant flow was switched to PCV and pressure was adjusted to maintain the same tidal volume(VT) received on VCV. Other ventilator settings were kept constant. Before changing the ventilatory mode, WOBp, VT, minute ventilation(VE), respiratory rate(RR), peak airway pressure (Ppeak), peak inspiratory flow rate(PIFR) and pressure-time product(PTP) were measured. RESULTS: The mean VE and RR were not different between PCV and VCV during study period. The Ppeak was significantly lower in PCV than in VCV during VT,HIGH ventilation(p<0.05). PIFR was significantly higher in PCV than in VCV at both VT (p<0.05). During VT,LOW ventilation, WOBp and PTP in PCV(0.80?0.37 J/min, 164.5?74.4 cmH2O.S) were significantly lower than in VCV(1.06+/-0.39J /min, 256.4+/-107.5 cmH2O.S)(p<0.05). During VT,HIGH ventilation, WOBp and PTP in PCV(0.33+/-0.14 J/min, 65.7+/-26.3 cmH2O.S) were also significantly lower than in VCV(0.40+/-0.14 J/min, 83.4+/-35.1 cmH2O.S)(p<0.05). CONCLUSION: During assisted ventilation, PCV with deccelerating flow was more effective in reducing WOBp than VCV with constant flow. But since individual variability was shown, further studies are needed to confirm these results.

Adherence-induced gene expression in human alveolar macrophages / 결핵

Background: Neutrophils or monocytes separated in vitro by the adherence to plastic surface are known to be activated by surface adherence itself and subsequent experimental data might be altered by surface adherence. Adhesion molecules and gene transcription of the inflammatory mediators are known to be associated in this process. To evaluate whether adhesion molecule and transcriptional activation of the inflammatory substances are also involved in the activation of human alveolar macrophage by the adherence procedure, we designed this experiment. Method: Bronchoalveolar lavage was performed in the person whose lung of either side was confirmed to be normal by chest CT and alveolar macrophage was harvested. To measure the expression of Interleukin-8(IL-8) mRNA, manganese superoxide dismutase(SOD) mRNA and CD11/CD18 mRNA in human alveolar macrophage of both adherence state and suspension state, Northern blot analysis was done at 0, 2, 4, 8 and 24hrs after the adherence to plastic surface and during suspension state. Then, phorbol myristate acetate(PMA) and N-formyl-methionyl-leucyl- phenylalanine(fMLP) were added respectively in the same experimental condition. Result: 1) Human alveolar macrophages in the adherent state induced IL-8 mRNA and SOD mRNA expression which was maximal at 8 hours after the adherence to plastic surface. But we could not observe the upregulation of CD18 mRNA by surface adherence. 2) PMA induced these mRNA expression both in the adherent cell and the nonadherent cells, but the induction of mRNA expression by fMLP occurred only in the adherent cells. Conclusion: These results suggest that adherence of huamn alveolar macropahge is an important cell-activating event that may play a critical role in the modulation of lung inflammatory response.

Predictors for Benign Solitary Pulmonary Nodule in Tuberculosis-Endemic Area

BACKGROUND: Solitary pulmonary nodule (SPN) may show different pre- sentation in tuberculosis (TB)-endemic countries. The aim of this study was to identify clinical and radiological predictors favoring benign or malignant SPN in TB-endemic region. METHODS: Two hundred one SPNs in 201 consecutive Korean patients were included (< 3 cm in diameter, all confirmed by pathology or bacteriology, 93 benign and 108 malignant diseases). For clinical parameters, age, sex, smoking status and amount, and past history of pulmonary tuberculosis and diabetes mellitus were investigated retrospectively. For radiological parameters, size, location, margin characteristics, presence of calcification, pleural tag, surrounding satellite nodule, cavitation, internal low attenuation, open bronchus sign, surrounding ground-glass opacity, enhancement pattern of the SPNs and mediastinal lymph node (LN) enlargement were analyzed on chest CT scans. RESULTS: Patients with a older age (60.7+/-9.6 vs 56.2+/-13.1, p=0.008) and more than 40-pack years smoking (27.8% vs 14.0%, p=0.017) were more frequently related with malignant than benign SPN. On chest CT scans, spiculated margin, contrast enhancement more than 20 Hounsfield unit and presence of pleural tag and mediastinal LN enlargement were more frequently observed in malignant than benign SPNs. In contrast to previous studies, satellite lesions (21.5% vs 1.9%, p < 0.001) and cavitation (20.4% vs 5.6%, p=0.001) were more frequently seen in benign than malignant SPN. Positive predictive values of benignity were 90.9% and 76.0%, respectively, when satellite lesions and cavitation were found in cases of SPN. CONCLUSION: Satellite lesions and cavitation on chest CT scan could be useful predictors for benign SPN in TB-endemic areas.

Two Cases of Localized Nodular Myositis / 대한류마티스학회지

Localized nodular myositis is an uncommon benign inflammatory myopathy of unkonwn cause affecting skeletal muscle and, presenting as a localized painful swelling within the soft tissue of an extremity. Histological examination reveals lymphocytic infiltration, scattered muscle fiber necrosis and regeneration, and interstitial fibrosis. MRI finding is an enhancement with increased signal intensity around the lesion. We report two cases of localized nodular myositis presenting as pseudothrobothrombophlebitis. We believe this is the first case report of localized nodular myositis in Korea.

Herpes Simplex Virus Pneumonia in Immunocopmromised Host / 결핵

No abstract available.

Beneficial Effect of Midazolam in Bronchoscopy, Single-Blind, Randomized, Prospective Study / 대한내과학회지

OBJECTIVES: Although bronchoscopy is an important diagnostic tool for lung disease, patients compliance is low due to discomfort. Recently, midazolam which has a favorable anterograde amnesia effect and short action duration, has been used to relieve patients discomfort during bronchoscopy. Midazolam was investigated in order to see the beneficial effect and safety during bronchoscopy. METHODS: The study design was single blind, randomized, prospective. 102 patients were included, in whom bronchoscopy was performed between June, 19% and October, 1995 at Samsung Medical Center. They were categorized into midazolam group and control group. Patients were asked about the amnesic effect, discomfort of procedure and the willingness to repeat procedure. The consciousness level of patients during procedure, patient cooperation during procedure and ease of procedure were also reported by bronchoscopists. RESULTS: 1) The difference of oxygen saturation between two groups: There was no significant difference in oxygen saturation between midazolam group and control group before and after bronchoscopy. During procedure, however, mean oxygen saturations in midazolam group (90+/-6.4%) was significantly lower than in control group (93+/-4.7%)(p<0.05). 2) Evaluations by patients (1) Effect of amnesia: 41 patients (82%) in midazolam group could not recall the procedure but 52 patients (100%) recalled the entire procedure in control group. A favorable amnesic effects could be found in midazolam group(p<0.05). {2) The discomfort during the procedure: 43 patents(86%) did not experience discomfort from procedure in midazolam group but 25 patients(48%) complained of discomfort in control group (p<0.05). (3) Most patients except two(96%) were willing to repeat fiberoptic bronchoscopy in midazolam group but 13 patients (25%) answered that they would never repeat bronchoscapy. There was a statistically significant difference between two groups in the willingness to repeat bronchocopy (p<0.05). 3) The evaluations by bronchoscopists Cooperations of the patients and ease of procedure were not different between two groups. The patients in midazolam group except eight could not respond to verbal stimuli but most patients were awakened during procedure in control group(p<0.05). CONCLUSION: Midazolam is a good sedative agent for a patient to give a favorable amnesia, reduction of discomfort during bronchoscopy. We concluded that midazolam is a safe and useful sedative agent and midazolam may be used routinely during bronchoscopy. Monitoring of oxygen saturation, however, is essential to prevent severe hypoxia during procedure.

A Case of Postintubation Tracheal Stenosis Treated by Endoscopic Nd-YAG Laser and Balloon Catheter / 결핵

The complications of endotracheal intubation are inevitable, of which postintubation tracheal stenosis may be required for surgical resection with primary reconstruction. Before surgery, several less invasive therapeutic modalites including bougie dilatation, stenting, and Nd-YAG laser incision are still available in use. Especially, good results were noted in selected patients with lengthy scars of less than 1cm and without tracheomalacia using endoscopic laser incision and dilatation. We report a case of a 54 yr-old woman with postintubation tracheal stenosis who was successfully treated by endoscopic Nd-YAG laser incision and esophageal balloon catheter.

Perfluorocarbon Does Not Inhibit Chemokine Expression in Airway Epithelial Cells / 결핵

BACKGROUND: Liquid ventilation is associated with decreased inflammatory response in an injured lung. This study was performed to investigate if whether perfluorocarbon (PFC) can decrease chemokine expression in airway epithelial cells. METHODS : A549 cells were used for airway epithelial cells and perfluorodecalin for PFC. To expose cells to PFC, lower chamber of Transwell a plate was used. This study was performed in two parts. In the first part, we examined whether PFC could decrease chemokine expression in airway epithelial cells through inhibition of other inflammatory cells. Peripheral blood mononuclear cells (PBMC's) were isolated and stimulated with lipopolysaccharide (LPS, 10 mg/mL) for 24 hours with or without exposure to PFC. Then A549 cells were stimulated with conditioned media (CM) containing the culture supernatants of PBMC . After 24 hours, the expressions of interleukin-8 (IL-8) and RANTES were measured. In the second part of the study, we studied whether PFC could directly suppress chemokine expression in airway epithelial cells. A549 cells were stimulated for 24 hours with interleukin-1b and/or tumor necrosis factor-a with or without exposure to PFC (,)and then the chemokine expression was measured. Northern analysis was used to measure the mRNA expression (,) and ELISA was used for immunoreactive protein measurements in culture supernatant. RESULTS: 1. IL-8 and RANTES mRNA expression and immunoreactive protein production were increased significantly by CM from LPS-stimulated PBMC in A459 cells compared with CM from unstimulated PBCM(p<0.05) (,)but exposure of PFC had no significant effect on either mRNA expression immunoreactive protein expression. 2. IL-8 and RANTES mRNA expression and immunoreactive protein production were increased significantly by IL-1b and TNF-a in A549 cells(p<0.05)(,)but exposure of PFC had no significant effect on either mRNA expression or immunoreactive protein production. CONCLUSION: Decreased chemokine expression of airway epithelial cells may not be involved in decreased inflammatory response observed in liquid ventilation. Further studies on possible mechanisms of decreased inflammatory response are warranted.

Partial liquid ventilation with perfluorocarbon improves gas exchange and decreases inflammatory response in oleic acid-induced lung injury in beagles

The aim of this study was to determine the effect of partial liquid ventilation (PLV) using a perfluorocarbon (PFC) on gas exchange and lung inflammatory response in a canine acute lung injury model. After inducing severe lung injury by oleic acid infusion, beagle dogs were randomized to receive either gas ventilation only (control group, n = 6) or PLV (PLV group, n = 7) by sequential instillation of 10 mL/kg of perfluorodecalin (PFC) at 30 min intervals till functional residual capacity was attained. Measurements were made every 30 min till 210 min. Then the lungs were removed and bronchoalveolar lavage (BAL) (35 mL/kg) was performed on the right lung and the left lung was submitted for histologic analysis. There was significant improvement in PaO2 and PaCO2 in the PLV group compared to the control group (p < 0.05) which was associated with a significant decrease in shunt (p < 0.05). There was no significant difference in parameters of lung mechanics and hemodynamics. There was a significant decrease in cell count and neutrophil percentage in BAL fluid and significantly less inflammation and exudate scores in histology in the PLV group (p < 0.05). We conclude that PLV with perfluorodecalin improves gas exchange and decreases inflammatory response in the acutely-injured lung.