C-reactive protein level predicts need for medical intervention in pregnant women with SARS-CoV2 infection: A retrospective study.

AIM: To make effective use of the limited available hospital space during the Coronavirus disease 2019 (COVID-19) pandemic, we conducted this study to investigate the laboratory indices that identify pregnant women with SARS-CoV2 infection who require medical intervention. METHODS: We carried out a retrospective analysis of pregnant women positive for COVID-19 who were admitted to Hokkaido University Hospital from September 2020 to June 2021. Medical interventions included oxygen supplementation, systemic corticosteroids, or supplemental liquids to treat infection-related symptoms. RESULTS: Forty-two infected pregnant patients were admitted to the hospital, half of whom required medical intervention (n = 21). Fever, C-reactive protein (CRP), and platelet count are all associated with need for medical intervention. Of the 32 patients with a fever of ≥37.5°C on days 0-3 after onset of syndromes, 22 (69%) continued to have a fever on days 4-6, of which 19 (86.4%) required medical intervention. CRP level on days 4-6 predicted the presence or absence of medical intervention (area under the receiver operating characteristic curve = 0.913), with a sensitivity of 81% and specificity of 100% at a CRP cutoff of 1.28 mg/dL. CONCLUSIONS: The need for medical intervention in pregnant patients can be predicted with high accuracy using a CRP cutoff of 1.28 mg/dL on days 4-6 after onset of syndromes. The presence of fever also may be an easy marker for selecting subjects who need or will need therapeutic intervention. These could be an effective triage method to determine appropriate indications for the hospitalization of pregnant women in future outbreaks.

Implementation Status of Liver Function Tests for Monitoring Benzbromarone-Induced Hepatotoxicity: An Epidemiological Survey Using the Japanese Claims Database.

A major adverse effect of benzbromarone is hepatotoxicity. Therefore, periodic liver function tests are required at least for the first 6 months of benzbromarone administration. However, it is not clear whether the relevant blood tests are implemented appropriately. Here, we performed a cross-sectional survey of the implementation status of liver function tests in patients who were newly prescribed benzbromarone, using the Japanese large claims database. Male patients who were newly prescribed benzbromarone from January 2010 to December 2016 were included. We targeted patients who continued benzbromarone during the observation period (up to 180 d from the start of administration). The primary endpoint was the proportion of patients in whom periodic liver function tests were implemented. A periodic liver function test was defined as one or more liver function tests performed during both 1-90 and 91-180 d of initial benzbromarone administration. We labeled the tests as a "periodic test" or "non-periodic test" based on whether periodic liver function tests were performed or not, respectively. Furthermore, factors influencing non-periodic test were analyzed. Periodic testing was implemented only in 28.7% of patients. Additionally, factors such as number of hospital beds ≤19 (compared to 100-199 beds) and duration of the first prescription of benzbromarone were associated with non-periodic testing. Our study revealed that periodic liver function tests are not performed sufficiently in Japan. Thus, clinicians prescribing benzbromarone should be educated about the test. Our blood-test-based approach should be applied to other drugs and countries in future research.

Proposal of COVID-19 Clinical Risk Score for the management of suspected COVID-19 cases: a case control study.

BACKGROUND: No clinical scoring system has yet been established to estimate the likelihood of coronavirus disease (COVID-19) and determine the suitability of diagnostic testing in suspected COVID-19 patients. METHODS: This was a single-center, retrospective, observational study of patients with suspected COVID-19 and confirmed COVID-19. Patient background, clinical course, laboratory and computed tomography (CT) findings, and the presence of alternative diagnoses were evaluated. Clinical risk scores were developed based on clinical differences between patients with and without COVID-19. RESULTS: Among 110 patients suspected of having COVID-19, 60.9% underwent polymerase chain reaction (PCR) testing based on the judgment of physicians. Two patients were found to have COVID-19. The clinical characteristics of 108 non-COVID-19 patients were compared with those of 23 confirmed COVID-19 patients. Patients with COVID-19 were more likely to have a history of high-risk exposures and an abnormal sense of taste and smell. The COVID-19 group had significantly higher rates of subnormal white blood cell counts, lower eosinophil counts, and lower procalcitonin levels than the non-COVID-19 group. When blood test results, CT findings, and the presence of alternative diagnoses were scored on an 11-point scale (i.e., "COVID-19 Clinical Risk Score"), the COVID-19 group scored significantly higher than the non-COVID-19 group, more than four points in the COVID-19 group. All non-COVID patients who did not undergo PCR had a score of 4 or less. CONCLUSIONS: The COVID-19 Clinical Risk Score may enable the risk classification of patients suspected of having COVID-19 and can help in decision-making in clinical practice, including appropriateness of diagnostic testing. Further studies and prospective validation with an increased sample size are required.

Physicians' responses to computerized drug interaction alerts with password overrides.

BACKGROUND: Although evidence has suggested that computerized drug-drug interaction alert systems may reduce the occurrence of drug-drug interactions, the numerous reminders and alerts generated by such systems could represent an excessive burden for clinicians, resulting in a high override rate of not only unimportant, but also important alerts. METHODS: We analyzed physicians' responses to alerts of relative contraindications and contraindications for coadministration in a computerized drug-drug interaction alert system at Hokkaido University Hospital. In this system, the physician must enter a password to override an alert and continue an order. All of the drug-drug interaction alerts generated between December 2011 and November 2012 at Hokkaido University Hospital were included in this study. RESULTS: The system generated a total of 170 alerts of relative contraindications and contraindication for coadministration; 59 (34.7 %) of the corresponding orders were cancelled after the alert was accepted, and 111 (65.3 %) were overridden. The most frequent contraindication alert was for the combination of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors and fibrates. No incidents involving drug-drug interactions were reported among patients who were prescribed contraindicated drug pairs after an override. CONCLUSIONS: Although computerized drug-drug interaction alert systems that require password overrides appear useful for promoting medication safety, having to enter passwords to override alerts may represent an excessive burden for the prescribing physician. Therefore, both patient safety and physicians' workloads should be taken into consideration in future designs of computerized drug-drug interaction alert systems.

Annual change in pulmonary function and clinical phenotype in chronic obstructive pulmonary disease.

RATIONALE: Although the rate of annual decline in FEV1 is one of the most important outcome measures in chronic obstructive pulmonary disease (COPD), little is known about intersubject variability based on clinical phenotypes. OBJECTIVES: To examine the intersubject variability in a 5-year observational cohort study, particularly focusing on emphysema severity. METHODS: A total of 279 eligible patients with COPD (stages I-IV: 26, 45, 24, and 5%) participated. We conducted a detailed assessment of pulmonary function and computed tomography (CT) at baseline, and performed spirometry every 6 months before and after inhalation of bronchodilator. Smoking status, exacerbation, and pharmacotherapy were carefully monitored. Emphysema severity was evaluated by CT and annual measurements of carbon monoxide transfer coefficient. MEASUREMENTS AND MAIN RESULTS: Using mixed effects model analysis, the annual decline in post-bronchodilator FEV1 was -32±24 (SD) ml/yr (n=261). We classified the subjects of less than the 25th percentile as Rapid decliners, the 25th to 75th percentile as Slow decliners, and greater than the 75th percentile as Sustainers (-63±2, -31±1, and -2±1 [SE] ml/yr). Emphysema severity, but not %FEV1, showed significant differences among the three groups. Multiple logistic regression analysis demonstrated that the Rapid decliners were independently associated with emphysema severity assessed either by CT or carbon monoxide transfer coefficient. The Sustainers displayed less emphysema and higher levels of circulating eosinophils. CONCLUSIONS: Emphysema severity is independently associated with a rapid annual decline in FEV1 in COPD. Sustainers and Rapid decliners warrant specific attention in clinical practice.

Associations of COVID-19 Symptoms with Omicron Subvariants BA.2 and BA.5, Host Status, and Clinical Outcomes: A Registry-Based Observational Study in Sapporo, Japan.

Background: Previous SARS-CoV-2 infection and vaccination, coupled to rapid evolution of SARS-CoV-2 variants, have modified COVID-19 clinical manifestations. We characterized clinical symptoms of COVID-19 individuals in omicron BA.2 and BA.5 Japanese pandemic periods to identify omicron and subvariant associations between symptoms, immune status, and clinical outcomes. Methods: Individuals registered in Sapporo's web-based COVID-19 information system entered 12 pre-selected symptoms, days since symptom onset, vaccination history, SARS-CoV-2 infection history, and background. Symptom frequencies, variables associated with symptoms, and symptoms associated with progression to severe disease were analysed. Results: For all omicron-infected individuals, cough was the most common symptom (62.7%), followed by sore throat (60.7%), nasal discharge (44.3%), and fever (38.8%). Omicron BA.5 infection was associated with a higher symptom burden than BA.2 in vaccinated and unvaccinated individuals. Omicron breakthrough-infected individuals with ≥ 3 vaccinations or previous infection were less likely to exhibit systemic symptoms, but more likely to exhibit upper respiratory symptoms. Infected elderly individuals had lower odds for all symptoms, but, when symptoms were manifest, systemic symptoms were associated with an increased risk, whereas upper respiratory symptoms with a decreased risk, of severe disease. Conclusion: Host immunological status, omicron subvariant, and age were associated with a spectrum of COVID-19 symptoms and outcomes. BA.5 produced a greater symptom burden than BA.2. Vaccination and prior infection mitigated systemic symptoms and improved outcomes, but increased upper respiratory tract symptom burden. Systemic, but not upper respiratory, symptoms in the elderly heralded severe disease.

Associations of COVID-19 symptoms with omicron subvariants BA.2 and BA.5, host status, and clinical outcomes in Japan: a registry-based observational study.

BACKGROUND: Previous SARS-CoV-2 infection and vaccination, coupled with the rapid evolution of SARS-CoV-2 variants, have modified COVID-19 clinical manifestations. We aimed to characterise the clinical symptoms of COVID-19 individuals in omicron BA.2 and BA.5 Japanese pandemic periods to identify omicron and subvariant associations between symptoms, immune status, and clinical outcomes. METHODS: In this registry-based observational study, individuals registered in Sapporo's web-based COVID-19 information system entered 12 pre-selected symptoms, days since symptom onset, vaccination history, SARS-CoV-2 infection history, and background. Eligibility criteria included symptomatic individuals who tested positive for SARS-CoV-2 (PCR or antigen test), and individuals who were not tested for SARS-CoV-2 but developed new symptoms after a household member tested positive for SARS-CoV-2. Symptom prevalence, variables associated with symptoms, and symptoms associated with progression to severe disease were analysed. FINDINGS: Data were collected and analysed between April 25 and Sept 25, 2022. For 157 861 omicron-infected symptomatic individuals, cough was the most common symptom (99 032 [62·7%] patients), followed by sore throat (95 838 [60·7%] patients), nasal discharge (69 968 [44·3%] patients), and fever (61 218 [38·8%] patients). Omicron BA.5 infection was associated with a higher prevalence of systemic symptoms than BA.2 in vaccinated and unvaccinated individuals (adjusted odds ratio [OR] for fever: 2·18 [95% CI 2·12-2·25]). Omicron breakthrough-infected individuals with three or more vaccinations or previous infection were less likely to exhibit systemic symptoms (fever 0·50 [0·49-0·51]), but more likely to exhibit upper respiratory symptoms (sore throat 1·33 [1·29-1·36]; nasal discharge 1·84 [1·80-1·89]). Infected older individuals (≥65 years) had lower odds for all symptoms. However, when symptoms were manifest, systemic symptoms were associated with increased odds for severe disease (dyspnoea 3·01 [1·84-4·91]; fever 2·93 [1·89-4·52]), whereas upper respiratory symptoms were associated with decreased odds (sore throat 0·38 [0·24-0·63]; nasal discharge 0·48 [0·28-0·81]). INTERPRETATION: Host immunological status, omicron subvariant, and age were associated with a spectrum of COVID-19 symptoms and outcomes. BA.5 produced a higher systemic symptom prevalence than BA.2. Vaccination and previous infection reduced systemic symptom prevalence and improved outcomes but increased upper respiratory tract symptom prevalence. Systemic, but not upper respiratory, symptoms in older people heralded severe disease. Our findings could serve as a practical guide to use COVID-19 symptoms to appropriately modify health-care strategies and predict clinical outcomes for older patients with omicron infections. FUNDING: Japan Agency for Medical Research and Development.

Effects of molecular structural variants on serum Krebs von den Lungen-6 levels in sarcoidosis.

BACKGROUND: Serum Krebs von den Lungen-6 (KL-6), which is classified as human mucin-1 (MUC1), is used as a marker of sarcoidosis and other interstitial lung diseases. However, there remain some limitations due to a lack of information on the factors contributing to increased levels of serum KL-6. This study was designed to investigate the factors contributing to increased levels of serum KL-6 by molecular analysis. METHODS: Western blot analysis using anti-KL-6 antibody was performed simultaneously on the bronchoalveolar lavage fluid (BALF) and serum obtained from 128 subjects with sarcoidosis. RESULTS: KL-6/MUC1 in BALF showed three bands and five band patterns. These band patterns were associated with the MUC1 genotype and the KL-6 levels. KL-6/MUC1 band patterns in serum were dependent on molecular size class in BALF. Significantly increased levels of serum KL-6, serum/BALF KL-6 ratio and serum soluble interleukin 2 receptor were observed in the subjects with influx of high molecular size KL-6/MUC1 from the alveoli to blood circulation. The multivariate linear regression analysis involving potentially relevant variables such as age, gender, smoking status, lung parenchymal involvement based on radiographical stage and molecular size of KL-6/MUC1 in serum showed that the molecular size of KL-6/MUC1 in serum was significant independent determinant of serum KL-6 levels. CONCLUSIONS: The molecular structural variants of KL-6/MUC1 and its leakage behavior affect serum levels of KL-6 in sarcoidosis. This information may assist in the interpretation of serum KL-6 levels in sarcoidosis.

Impact of asthmatic control status on serum cystatin C concentrations.

BACKGROUND: To determine whether cystatin C accurately reflects renal function in asthma, we investigated serum cystatin C concentrations in a large number of asthmatic patients by adjusting for several confounding factors that might affect serum cystatin C concentrations. METHODS: A total of 126 asthmatic patients and 126 healthy volunteers, matched for age and gender, were studied. RESULTS: Serum cystatin C concentrations in symptomatic subjects with asthma were significantly higher than in healthy controls (p < 0.001) and asymptomatic subjects with asthma (p = 0.007), whereas no significant difference was observed between healthy controls and asymptomatic subjects. In asthmatic subjects, serum cystatin C concentrations were not influenced by inhaled corticosteroid (ICS). However, serum cystatin C concentrations were significantly higher in subjects who were regularly treated by oral corticosteroid (OCS) (p = 0.001). CONCLUSIONS: Serum cystatin C concentrations are elevated in asthmatic patients; particularly while symptomatic and/or taking OCS but not ICS. Serum cystatin C concentrations may not accurately reflect renal function in those patients.

Beta2-adrenergic receptor polymorphisms as a determinant of preferential bronchodilator responses to ß2-agonist and anticholinergic agents in Japanese patients with chronic obstructive pulmonary disease.

BACKGROUND: Previous studies have shown that polymorphisms in the ß2-adrenergic receptor gene (ADRB2) may influence bronchodilator response (BDR) to both ß2-agonists and anticholinergics, possibly by intracellular cross-talk, but in opposite ways, in the Japanese population. We hypothesized that the preferential response to either class of bronchodilators might be determined by ADRB2 polymorphisms in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: To examine the association of ADRB2 polymorphisms and preferential BDR to ß2-agonists and anticholinergics in patients with COPD. DESIGN AND PARTICIPANTS: The participants had been enrolled in the Hokkaido COPD cohort study. BDR to either class of bronchodilators (salbutamol or oxytropium, 0.4 mg) was measured every 6 months for 2 years. Considering the variation of BDR within and between days, mean values of postbronchodilator increases in forced expiratory volume in 1 s (ΔFEV1) for the two agents measured at two different visits were initially used for the primary analysis (N=189). To confirm the results of the primary analysis, ΔFEV1 measured at a single visit was also used for secondary analyses. RESULTS: Although a significant correlation between BDRs to salbutamol and to oxytropium was observed (P<0.001, r=0.36), there were individuals who responded preferentially to one of the two agents. When the participants were classified into two groups based on the bronchodilator causing the better response (salbutamol-dominant group and oxytropium-dominant group), Arg allele was significantly more common in the oxytropium-dominant group than in the salbutamol-dominant group (0.001

Inhaled granulocyte/macrophage-colony stimulating factor as therapy for pulmonary alveolar proteinosis.

RATIONALE: Inhaled granulocyte/macrophage-colony stimulating factor (GM-CSF) is a promising therapy for pulmonary alveolar proteinosis (PAP) but has not been adequately studied. OBJECTIVES: To evaluate safety and efficacy of inhaled GM-CSF in patients with unremitting or progressive PAP. METHODS: We conducted a national, multicenter, self-controlled, phase II trial at nine pulmonary centers throughout Japan. Patients who had lung biopsy or cytology findings diagnostic of PAP, an elevated serum GM-CSF antibody level, and a Pa(O(2)) of less than 75 mm Hg entered a 12-week observation period. Those who improved (i.e., alveolar-arterial oxygen difference [A-aDO(2)] decreased by 10 mm Hg) during observation were excluded. The rest entered sequential periods of high-dose therapy (250 microg Days 1-8, none Days 9-14; x six cycles; 12 wk); low-dose therapy (125 microg Days 1-4, none Days 5-14; x six cycles; 12 wk), and follow-up (52 wk). MEASUREMENTS AND MAIN RESULTS: Fifty patients with PAP were enrolled in the study. During observation, nine improved and two withdrew; all of these were excluded. Of 35 patients completing the high- and low-dose therapy, 24 improved, resulting in an overall response rate of 62% (24/39; intention-to-treat analysis) and reduction in A-aDO(2) of 12.3 mm Hg (95% confidence interval, 8.4-16.2; n = 35, P < 0.001). No serious adverse events occurred, and serum GM-CSF autoantibody levels were unchanged. A treatment-emergent correlation occurred between A-aDO(2) and diffusing capacity of the lung, and high-resolution CT revealed improvement of ground-glass opacity. Twenty-nine of 35 patients remained stable without further therapy for 1 year. CONCLUSIONS: Inhaled GM-CSF therapy is safe, effective, and provides a sustained therapeutic effect in autoimmune PAP. Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN18931678), www.jmacct.med.or.jp/english (JMA-IIA00013).

[A case of multifocal micronodular pneumocyte hyperplasia without clinical findings of tuberous sclerosis].

A 30-year-old woman was referred because of multiple ground-glass opacities (GGOs) on chest CT examination. Lung biopsy was performed. Histologically, multifocal well-demarcated nodular lesions comprising proliferation of type II pneumocytes with mild fibrous thickening of the alveolar septa were observed in the lung tissue. We made a histopathologic diagnosis of multifocal micronodular pneumocyte hyperplasia (MMPH). Neither the clinical findings nor the family history of the patient suggested tuberous sclerosis (TSC). MMPH is a pulmonary manifestation of tuberous sclerosis, together with lymphangioleiomyomatosis (LAM). MMPH should be considered as a differential diagnosis of multiple GGOs in the lung even when findings of TSC and LAM are not recognized.

Characteristics of COVID-19 patients admitted into two hospitals in sapporo, Japan: Analyses and insights from two outbreak waves.

BACKGROUND: Coronavirus disease (COVID-19) emerged in January 2020 in Sapporo city, and the outbreak has shown two peaks. METHODS: A total of 260 COVID-19 patients were enrolled and categorized into three groups according to the pandemic pattern, jobs and situation, and disease severity. We compared clinical characteristics according to these categories. RESULTS: We found two pandemic peaks, and the proportion of patients and health providers who were infected in other hospitals had increased in the latter two periods (period 2: 49.6%, period 3: 32.7%). Particularly, the proportion of infected health providers was 27% in period 2, and they tended to be younger females with a mild condition. Severity of the disease (requirement of oxygen and/or mechanical ventilation) was associated with advanced age, and all the patients who died during admission were over 60 years old. CONCLUSIONS: We reported the temporal dynamics and characteristics of the COVID-19 pandemic in Sapporo city, Japan. This survey from the viewpoint of the hospital provides a new insight into and a better guide for the further management of the COVID-19 pandemic.

Aging enhances susceptibility to cigarette smoke-induced inflammation through bronchiolar chemokines.

Cigarette smoking and aging are major risk factors for chronic obstructive pulmonary disease. An unsolved question is whether elderly lungs are particularly vulnerable to cigarette smoke (CS) exposure. In this study, we used a mouse model to test the hypothesis that aging increases the susceptibility to CS-induced pulmonary inflammation. We subjected 9-week-old and 69-week-old C57BL/6J mice to CS (whole-body exposure, 90 min/d), and evaluated neutrophil infiltration in the lungs, the levels of keratinocyte-derived chemokine (KC) and macrophage inflammatory protein (MIP)-2 in bronchoalveolar lavage fluid, and mRNA expression in bronchiolar epithelium retrieved by laser capture microdissection. The 69-week-old mice showed a greater number of neutrophils and higher levels of bronchiolar KC and MIP-2 expression than 9-week-old mice after 9 days of CS exposure. Furthermore, single CS exposure induced the rapid up-regulation of KC and MIP-2 in bronchiolar epithelium in both 9-week-old and 69-week-old mice, and the much higher levels in 69-week-old mice were associated with greater nuclear translocation of NF-kappaB. In contrast, no age-related differences were observed in the bronchiolar expression of NF-E2-related factor 2-regulated antioxidant and detoxification genes, heme oxygenase-1, reduced nicotinamide adenine dinucleotide phosphate quinone reductase 1, and glutamate-cysteine ligase, modifier unit, or antioxidant activity in bronchoalveolar lavage fluid, regardless of CS exposure. In summary, aging increases susceptibility to CS-induced inflammation in a mouse model, and robust mRNA up-regulation and nuclear translocation of NF-kappaB in bronchiolar epithelium may be involved.

A case of follicular bronchiolitis associated with asthma, eosinophilia, and increased immunoglobulin E.

A 49-year-old woman, who had been diagnosed with asthma, showed a bilateral diffuse pattern of small centrilobular nodules on CT. Laboratory data revealed peripheral eosinophilia and a marked increase in total serum IgE levels. The nodules detected on CT were initially considered to be associated with bronchiolar infiltration of eosinophils. Pathological findings from thoracoscopy revealed infiltration of eosinophils into the airway lumen and walls, goblet cell hyperplasia, and thickening of the basement membrane in large bronchi, consistent with asthma. However, hyperplastic lymphoid follicles with reactive germinal centers were observed along the bronchioles. The follicles had no evidence of monoclonality suggested by immunohistological analysis, and no remarkable infiltrates of eosinophils, suggesting follicular bronchiolitis (FB). After treatment with prednisolone, the small diffuse nodules improved markedly, and peripheral eosinophilia and total serum IgE levels also decreased. To the best of our knowledge, this is the first documented case report of FB associated with asthma, eosinophilia, and elevated IgE with a definite pathophysiological diagnosis.

Levels of transferrin in bronchoalveolar lavage fluid in sarcoidosis.

There has been only one report showing high levels of transferrin (Tf) in bronchoalveolar lavage fluid (BALF) in patients with sarcoidosis. This study was designed to assess the levels of Tf in both BALF and serum and to examine the relationship between the levels of Tf and other disease markers in sarcoidosis. Subjects were 64 sarcoidosis and 10 healthy controls. Tf in BALF and serum was measured by nephelometric assay. Median Tf levels in BALF from sarcoidosis was 0.70 (range, 0.00-3.97) mg/dl, which was significantly higher compared with controls (0.36 (range, 0.00-1.02) mg/dl; p = 0.005). In contrast, median Tf levels in serum from sarcoidosis was 258 (range, 171- 383) mg/dl, which was significantly lower compared with controls (322 (range, 234-356) mg/dl; p = 0.003). Tf levels in BALF were significantly correlated with both the percentage of lymphocytes (r = 0.617, p = 0.001) and serum angiotensin-converting enzyme activity (r = 0.363, p = 0.003) and serum soluble interleukin-2 receptor (r = 0.450, p = 0.001) in sarcoidosis. Levels of Tf in BALF from patients with sarcoidosis were not influenced by smoking status. The levels of Tf in sarcoidosis are high in BALF, but low in serum. Increased levels of Tf in BALF may reflect the disease activity.

[Intravascular large B-cell lymphoma with massive pulmonary lesions].

A 61-year-old man was admitted to our hospital with dyspnea on effort. Neither computed tomography scan nor chest X-ray film detected any specific findings that could explain hypoxemia. Since (67)Ga scintigraphy showed abnormal uptake in the bilateral lungs, transbronchial lung biopsy (TBLB) was performed. The TBLB specimen was diagnosed as intravascular large B-cell lymphoma (IVLBCL). There was no involvement of any other organ considered typical of IVLBCL. In cases showing clinical findings such as hypoxia despite mild pulmonary radiographic changes, a definitive diagnosis should be made using methods such as TBLB with consideration given to the possibility of IVLBCL.

[Flow-volume curve as an aid to diagnosis in double aortic arch masquerading as asthma in a young adult].

We describe a young adult with double aortic arch who for several years had experienced stridor during exercise. He had been given a diagnosis of exercise-induced asthma, also known as hyperventilation syndrome. Antiasthmatic drugs, including inhaled corticosteroids and a short-acting bronchodilator, in addition to antidepressants, did not improve his symptoms. He had a history of allergic rhinitis and a familial history of asthma, but no signs of asthma as assessed by expectorated sputum and airway responsiveness (Dmin). However, flow-volume curves demonstrated a pattern consistent with upper airway constriction. Computed tomography confirmed severe tracheal narrowing caused by a double aortic arch. Compressive tracheal narrowing was also evaluated by fiber-optic tracheobronchoscopy. A treadmill exercise study induced respiratory distress with audible stridor that resolved itself without intervention. He underwent surgical division of the left aortic arch, which relieved the stridor during exercise. The flow-volume curve improved but constriction was still indicated even at 1.5 years after surgery. Double aortic arch should be considered in the differential diagnosis of drug-resistant stridor. This case re-emphasizes the value of flow-volume curves for diagnosing upper-airway obstruction.

Rapidly progressive organizing pneumonia associated with COVID-19.

We report a case of clinically diagnosed secondary organizing pneumonia (SOP) associated with coronavirus disease 2019 (COVID-19). A 70-year-old woman who had been diagnosed with COVID-19 was admitted to Hokkaido University Hospital. Although her fever, cough, dyspnea, and serum C-reactive protein levels improved, she developed rapidly progressive respiratory failure and computed tomography revealed the development of bilateral lung consolidation. Her dyspnea was relieved, and her oxygenation levels and radiological findings improved after commencing corticosteroid treatment. Blood biomarkers for interstitial lung disease, Krebs von den Lungen-6 (KL-6) and surfactant protein D (SP-D), showed different responses during the clinical course of her disease. Evaluation of serial changes in levels of KL-6 and SP-D may help diagnose and monitor COVID-19-associated organizing pneumonia (OP). Clinicians should be aware that SOP can develop in response to COVID-19 and that these patients may benefit from the use of steroids.