Prediction of oxygen supplementation by a deep-learning model integrating clinical parameters and chest CT images in COVID-19.

PURPOSE: As of March 2023, the number of patients with COVID-19 worldwide is declining, but the early diagnosis of patients requiring inpatient treatment and the appropriate allocation of limited healthcare resources remain unresolved issues. In this study we constructed a deep-learning (DL) model to predict the need for oxygen supplementation using clinical information and chest CT images of patients with COVID-19. MATERIALS AND METHODS: We retrospectively enrolled 738 patients with COVID-19 for whom clinical information (patient background, clinical symptoms, and blood test findings) was available and chest CT imaging was performed. The initial data set was divided into 591 training and 147 evaluation data. We developed a DL model that predicted oxygen supplementation by integrating clinical information and CT images. The model was validated at two other facilities (n = 191 and n = 230). In addition, the importance of clinical information for prediction was assessed. RESULTS: The proposed DL model showed an area under the curve (AUC) of 89.9% for predicting oxygen supplementation. Validation from the two other facilities showed an AUC > 80%. With respect to interpretation of the model, the contribution of dyspnea and the lactate dehydrogenase level was higher in the model. CONCLUSIONS: The DL model integrating clinical information and chest CT images had high predictive accuracy. DL-based prediction of disease severity might be helpful in the clinical management of patients with COVID-19.

Thoracic empyema caused by Alloscardovia omnicolens and Bifidobacteriumdentium.

A 62-year-old man was admitted to our emergency department with the complaint of worsening dyspnea after initiating anti-tuberculous therapy (isoniazid [300 mg/day], rifampicin [600 mg/day], ethambutol [750 mg/day], and pyrazinamide [1,500 mg/day]) for tuberculous pleuritis. His oral hygiene status was poor. The patient had no significant past medical history. However, he had a history of smoking (10 cigarettes per day for 45 years) and was a social drinker. Chest radiography revealed increased right pleural effusion and pneumothorax. The pleural fluid was purulent, and the culture grew Alloscardovia omnicolens, Bifidobacterium dentium, and Prevotella loescheii. He was treated with antibiotics (3 g of intravenous ampicillin/sulbactam every 6 h, which was changed to oral amoxicillin/clavulanate potassium on day 34) in addition to anti-tuberculous therapy, he underwent chest tube insertion, and subsequently improved. Bifidobacteriaceae are commensal flora of the mouth and pulmonary infections caused by these organisms are extremely rare. Nevertheless, clinicians should consider these organisms as a possible cause of pulmonary infections, and consider that respiratory infections caused by commensal flora of the mouth may occur during the treatment of other diseases in patients with poor oral hygiene.

Peribronchial Connective Tissue Infection Caused by Bifidobacterium longum and Veillonella Species Mimicking Lung Cancer.

An 86-year-old woman was admitted for the investigation of atelectasis of the upper lobe of her right lung with a mass shadow in the hilum (Golden S sign). Chest computed tomography revealed swollen connective tissue around the right bronchus, and needle aspirate grew Bifidobacterium longum and Veillonella species. She was diagnosed with peribronchial connective tissue infection, and her condition improved with antibiotics. Although this sign is strongly suggestive of malignant disease, benign disease should be considered in the differential diagnosis. Pulmonary infection caused by Bifidobacterium longum is extremely rare; however, clinicians should consider it as a possible cause of pulmonary infections.

Evaluation of a novel urinary antigen test kit for diagnosing Legionella pneumonia.

OBJECTIVES: The aim of this study was to evaluate the diagnostic utility of a novel test kit that could theoretically detect all serogroups of Legionella pneumophila for diagnosing Legionella pneumonia, in comparison with existing kits. METHODS: This study was conducted in 16 hospitals in Japan from April 2016 to December 2018. Three urinary antigen test kits were used: the novel kit (LAC-116), BinaxNOW Legionella (Binax), and Q-line Kyokutou Legionella (Q-line). In addition, sputum culture and nucleic acid detection tests and serum antibody tests were performed where possible. The diagnostic accuracy and correlations of the novel kit with the two existing kits were analyzed. RESULTS: In total, 56 patients were diagnosed with Legionella pneumonia. The sensitivities of LAC-116, Binax, and Q-line were 79%, 84%, and 71%, respectively. The overall match rate between LAC-116 and Binax was 96.8% and between LAC-116 and Q-line was 96.4%. One patient had L. pneumophila serogroup 2, and only LAC-116 showed a positive result, whereas Binax and Q-line did not. CONCLUSIONS: The novel Legionella urinary antigen test kit was useful for diagnosing Legionella pneumonia. In addition, it could detect Legionella pneumonia caused by non-L. pneumophila serogroup 1.

Pulmonary Nocardiosis: A Clinical Analysis of 30 Cases.

Objective Pulmonary nocardiosis frequently develops as an opportunistic infection in patients with malignant tumor and is treated with steroids. This study was performed to clarify the clinical features of pulmonary nocardiosis in Japan. Methods The patients definitively diagnosed with pulmonary nocardiosis at our hospital between January 1995 and December 2015 were retrospectively investigated. Results Nineteen men and 11 women (30 in total) were diagnosed with pulmonary nocardiosis. Almost all patients were complicated by a non-pulmonary underlying disease, such as malignant tumor or collagen vascular disease, or pulmonary disease, such as chronic obstructive pulmonary disease or interstitial pneumonia, and 13 patients (43.3%) were treated with steroids or immunosuppressors. Gram staining was performed in 29 patients, and a characteristic Gram-positive rod was detected in 28 patients (96.6%). Thirty-one strains of Nocardia were isolated and identified. Seven strains of Nocardia farcinica were isolated as the most frequent species, followed by Nocardia nova isolated from 6 patients. Seventeen patients died, giving a crude morality rate of 56.7% and a 1-year survival rate of 55.4%. The 1-year survival rates in the groups with and without immunosuppressant agents were 41.7% and 59.7%, respectively, showing that the outcome of those receiving immunosuppressants tended to be poorer than those not receiving them. Conclusion Pulmonary nocardiosis developed as an opportunistic infection in most cases. The outcome was relatively poor, with a 1-year survival rate of 55.4%, and it was particularly poor in patients treated with immunosuppressant agents. Pulmonary nocardiosis should always be considered in patients presenting with an opportunistic respiratory infection, and an early diagnosis requires sample collection and Gram staining.

Acute myelogenous leukemia with Leptotrichia trevisanii bacteremia.

A 74-year-old woman visited an otolaryngology clinic with pharyngeal pain, and was diagnosed with a peritonsillar abscess. She received antibiotics and underwent incisional drainage, but displayed high white blood cell and blast cell counts, and was referred to our hospital. Gram-negative rods (Leptotrichia trevisanii) were detected in blood cultures performed on admission. She was diagnosed with bacteremia and acute myelogenous leukemia (FAB classification: M1). After antibiotic therapy, she temporarily recovered from the bacteremia, but subsequently died on day 34. Although Leptotrichia trevisanii bacteremia is extremely rare, clinicians should consider it in cases involving immunocompromised patients with oral lesions.

[Two cases of anaerobic empyema including Actinomyces].

We report 2 cases of empyema including Actinomyces spp. Case 1 was a 66-year-old man with fever and left pleural effusion, Actinomyces israelii and 2 other microbes were isolated. Case 2 was a 52-year-old male inpatient who developed empyema during treatment of upper gastrointestinal bleeding. Actinomyces odontolyticus and 3 other microbes were cultured in pleural effusion. Empyema caused by Actinomyces spp. is rare, in particular Actinomyces odontolyticus is rarely isolated and only 4 cases have been reported in Japan.

[A case of chronic empyema caused by Salmonella Livingstone with soft-tissue abscess].

A 65-year-old man with old tuberculous pleuritis was admitted to our hospital because of swelling and heat on the right upper abdomen on December 8, 2006. Computed tomography showed the presence of thickening and calcification of the right pleura, capsular effusion, and soft-tissue swelling of the right upper abdomen. Salmonella Livingstone was isolated from the aspiration specimen of the capsular effusion. Chronic empyema caused by Salmonella Livingstone with soft-tissue abscess was diagnosed, and was treated with 400 mg per day levofloxacin. Salmonella spp. is known as a common pathogen of gastroenteritis. Pleuropulmonary Salmonella infection is rare, and only 5 cases have been reported in Japan. However, this organism can cause respiratory tract infection in a patient with an impaired host defence system such as old tuberculosis.

[Clinical features of Q-fever pneumonia].

A retrospective study was undertaken to investigate the clinical aspects of Q-fever pneumonia. Six sporadic cases, 5 men and 1 woman, aged between 36 and 81 years were diagnosed by testing paired serum samples using an indirect immunofluorescence assay from July 2004 to June 2007. Of these, 5 suffered from concomitant or chronic disease. The predominant clinical features were fever, cough, sputum, and chest pain. The WBC count was within normal values in half of the patients. C-reactive protein was elevated in all patients. Liver dysfunction was noted in 2 patients. Chest computed tomography revealed air space consolidation and small nodules in all patients and pleural effusion in 1 patient. Anti-phase II IgG titers of paired serum samples were elevated, but anti-phase II IgM titers were within normal limits in all the patients. Antibiotics were given to all the patients, and, beta-lactum agents were prescribed for 3 patients. The outcome was favorable in all the patients. These patients demonstrated nonspecific clinical, radiological, and laboratory manifestations, and we were able to distinguish Q-type pneumonia from other forms of community-acquired pneumonia only by testing anti-phase II IgG titers of paired serum samples.

Assessment of the homogeneous efficacy of carbon ions in the spread-out Bragg peak for human lung cancer cell lines.

PURPOSE: The aim of this study was to assess the radiosensitivities and homogeneous efficacy in the spread-out Bragg peak (SOBP) for lung cancer cell lines exposed to carbon ions. MATERIALS AND METHODS: The dose-dependent survival rates of seven cell lines exposed to carbon ions, fast neutrons, and photons were obtained using colony-forming assays in vitro. The relative biological effectiveness (RBE) of carbon ions and fast neutrons to photons was determined by comparing the doses at the 10% and 1% survival levels. RESULTS: The RBEs at 13, 40, 50, and 80 keV/microm were 1.20-1.29, 1.55-1.80, 1.57-2.00, and 1.69-2.58, respectively, at the 10% survival level. The RBE of 290 MeV carbon ions increased with increasing linear energy transfer. The biological dose (relative physical dose x RBE) distributions in the SOBP did not statistically differ at the proximal, mid, or distal points at the 10% (p = 0.945) and 1% (p = 0.211) survival levels, respectively; however, deviation of the biological dose at 10% and 1% survival were 3%-16% and 6%-24%, respectively. Furthermore, 290 MeV carbon ions at 80 keV/microm in the SOBP were nearly equivalent to 30 MeV fast neutrons. CONCLUSION: Our results demonstrate nearly homogeneous effectiveness in the SOBP, although we are aware of the deviation in some cell lines.

[Pulmonary infection with Nocardia species: a report of 10 cases].

OBJECTIVE: To investigate the clinical features of pulmonary nocardiosis. PATIENTS AND METHODS: We retrospectively reviewed ten consecutive patients (5 men, 5 women; aged 25 to 80 years (average 49.3 years)) with confirmed bacteriological pulmonary nocardiosis from 1998 to 2003. Patients were divided into two groups: infected (8 patients) and isolated (2 patients). RESULTS: All patients had predisposing factors and/or pulmonary disease. Six were immunosuppressed by steroid therapy with or without other immunosuppressive drugs. The overall survival rate among infected patients was 75.0% (6/8), but the survival rate of patients who were diagnosed speedily by a gram-stain procedure was 85.7% (6/7). CONCLUSIONS: Although pulmonary nocardiosis is difficult to diagnose, prompt use of the gram-staining procedure and appropriate treatment appeared to improve survival. And new diagnostic method is desirable.

Assessment of myocardial perfusion and fatty acid metabolism in a patient with Churg-Strauss syndrome associated with eosinophilic heart disease.

Churg-Strauss syndrome is characterized by asthma, eosinophilia and systemic necrotizing vasculitis; cardiac involvement (ie, eosinophilic heart disease) is the major cause of morbidity and mortality, although there are no reports of an association between left ventricular dysfunction because of eosinophilic heart disease and myocardial blood flow or myocardial fatty acid metabolism. A patient presented with Churg-Strauss syndrome associated with eosinophilic heart disease that had progressed to dilated cardiomyopathy. Coronary angiography, thallium-201 ((201)Tl) and iodine-123 beta-methyl-iodophenyl pentadecanoic acid ((123)I BMIPP) myocardial single photon emission computed tomography (SPECT) were performed to evaluate left ventricular dysfunction. Although coronary angiography was normal and (201)Tl SPECT showed no apparent image defect, (123)I BMIPP SPECT showed diffuse decreased accumulation, excepting the apex. The left ventricular dysfunction in patients with eosinophilic heart disease is associated with impaired myocardial fatty acid metabolism rather than with impaired myocardial blood flow.

Lung abscess caused by Actinomyces odontolyticus.

A 64-year-old woman with periodontal disease was admitted because of fever, right chest pain, and bloody sputum. Her chest radiograph revealed a nodular shadow in the right middle lung fields. From the results of a needle aspiration biopsy, she was diagnosed with a lung abscess due to Actinomyces odontolyticus (A. odontolyticus) and Streptococcus spp. The patient improved quickly with antibiotics. To our knowledge, only nine cases of pulmonary infection due to A. odontolyticus have been reported, and we report the first case in Japan. Although respiratory disease caused by A. odontolyticus is rare, the association of this organism should be considered even in healthy individuals.

Suppression of a DNA double-strand break repair gene, Ku70, increases radio- and chemosensitivity in a human lung carcinoma cell line.

Ku70 protein, cooperating with Ku80 and DNA-dependent protein kinase (DNA-PK) catalytic subunit (DNA-PKcs), is involved in DNA double-strand break (DNA DSB) repair and V(D)J recombination. Recent studies have revealed increased ionizing radiosensitivity in Ku70-deficient cells. The presented study, using a human squamous cell lung carcinoma cell line, demonstrated that introduction of an antisense Ku70 nucleic acid made the cells more radio- and chemosensitive than the parental cells. Ku70 protein expression was suppressed in the cells with antisense Ku70 construct when compared to the wild-type cells. A relatively small but statistically significant increase in radiosensitivity of the cells was achieved by the introduction of the antisense Ku70. The increased radiosensitivity in vitro was accompanied by an approximately two-fold increase in alpha and alpha/beta values in a linear-quadratic model. The antisense Ku70 increased the chemosensitivity of the cells to some DNA-damaging agents such as bleomycin and methyl methanesulfonate, but not to cisplatin, mitomycin C, and paclitaxel. This system provides us with partial suppression of Ku70, and will be a useful experimental model for investigating the physiological roles of the DNA DSB repair gene.