Optical Biopsies Using Probe-Based Confocal Laser Endomicroscopy for Autoimmune Pulmonary Alveolar Proteinosis.

INTRODUCTION: Increasing numbers of cases of mild asymptomatic pulmonary alveolar proteinosis (PAP) are being reported with the recent increase in chest computed tomography (CT). Bronchoscopic diagnosis of mild PAP is challenging because of the patchy distribution of lesions, which makes it difficult to obtain sufficient biopsy samples. Additionally, the pathological findings of mild PAP, particularly those that differ from severe PAP, have not been fully elucidated. This study aimed to clarify the pathological findings of mild PAP and the usefulness of optical biopsy using probe-based confocal laser endomicroscopy (pCLE). METHODS: We performed bronchoscopic optical biopsy using pCLE and tissue biopsy in 5 consecutive patients with PAP (three with mild PAP and two with severe PAP). We compared the pCLE images of mild PAP with those of severe PAP by integrating clinical findings, tissue pathology, and chest CT images. RESULTS: pCLE images of PAP showed giant cells with strong fluorescence, amorphous substances, and thin alveolar walls. Images of affected lesions in mild PAP were equivalent to those obtained in arbitrary lung lesions in severe cases. All 3 patients with mild PAP spontaneously improved or remained stable after ≥3 years of follow-up. Serum autoantibodies to granulocyte-macrophage colony-stimulating factor were detected in all 5 cases. CONCLUSION: Optical biopsy using pCLE can yield specific diagnostic findings, even in patients with mild PAP. pCLE images of affected areas in mild and severe PAP showed similar findings, indicating that the dysfunction level of pathogenic alveolar macrophages in affected areas is similar between both disease intensities.

Post-discharge clinical, laboratory and radiographic features of coronavirus disease 2019 (COVID-19) patients at university hospitals in Japan.

Objectives: Coronavirus disease 2019 (COVID-19) has affected nearly half million people in Japan. However, information on the prolonged symptoms as well as laboratory and radiographic findings after hospital discharge remains limited. Methods: We retrospectively collected the symptoms, laboratory test results, and chest imaging results of COVID-19 patients at the time of the hospital admission and the ambulatory visits after discharge at two university hospitals between July and December 2020. Patients: A total of 126 COVID-19 patients, including of 88 with mild to moderate disease and 38 with severe to critical disease, were included. The time between symptom onset and the first outpatient visit was 46 days (Interquartile range, 39 to 55). Results: At the ambulatory visits, 36.5% of patients had at least one symptom. The most frequent symptom was shortness of breath (12.8%), followed by cough (11.1%), and fatigue (8.8%). Of 120 patients with post-discharge laboratory test results, 27 patients (22.5%) had abnormal alanine aminotransferase levels, and 35 patients (29.1%) had lymphocytopenia, including 24 and 27 mild and moderate patients. Of 122 patients with post-discharge chest computed tomography (CT) scans, 105 (83.3%) had abnormal findings. This abnormality was found in both mild to moderate and severe patients. Conclusions: Shortness of breath, abnormal liver function test results and chest CT images often persisted for at least one month after discharge, even when symptoms were mild or moderate during hospitalization.

Syphilis With Multiple Pulmonary Nodules and Bone Lesions Detected on Computed Tomography and 18F Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography.

Syphilis can cause a wide range of systemic manifestations, such as papular rash, malaise, weight loss, muscle aches, generalized lymphadenopathy, and meningitis. However, pulmonary involvement in patients with secondary syphilis is thought to be relatively rare. Moreover, bone involvement in patients with secondary syphilis is also considered rare, and only a few cases of involvement of lung and bone in such patients have been reported. In this paper, we report a case of secondary syphilis with pulmonary involvement in the form of multiple nodules with low attenuation areas, lymphadenopathy and multiple bone lesions detected on computed tomography and 18F fluorodeoxyglucose-positron emission tomography/computed tomography.

Availability of Home sleep apnea test equipment LS-140 on a comparison with Polysomnography.

OBJECTIVE: The prevalence of obstructive sleep apnea (OSA) in Japan is 9% among males and 3% among females. Up to 2.5 million patients are estimated to suffer from the disease, but limited number of facilities are capable of carrying out polysomnography (PSG), leaving more than 80% of these individuals are undiagnosed. In recent years, the development of new portable sleep monitoring (PMs) devices has been remarkable. We evaluate the correlation between the results of the LS-140 PMs device (Fukuda Denshi Tech Co. Ltd.), released in 2017, and those of PSG. METHODS: We obtained contemporaneous data from the same patients by equipping 58 patients with PMs (LS-140) devices while they underwent PSG. Our primary outcome was Case 2 of the intraclass correlation coefficient (ICC), i.e., the ICC (2.1). And we used a Bland-Altman analysis to compare the apnea-hypopnea index (AHI) given by PSG and the respiratory event index (REI) given by LS-140 and examined the sensitivity and specificity of the REI relative to the AHI in the diagnosis of OSA. We also carried out the same comparison but in terms of the presence or absence of periodic limb movements (PLMs). RESULTS: The ICC (2.1) between The REI and the AHI was 0.944, a rather high value (p<0.0001). The mean difference between AHI and REI values was -3.6 (p<0.0001), indicating a negative fixed bias. Sensitivity may decrease in groups with PLMs. CONCLUSION: The REI and the AHI are highly correlated, giving LS-140 sufficient diagnostic sensitivity and specificity to screen for OSA.

Fatal disseminated mucormycosis associated with COVID-19.

Secondary fungal infections are a critical problem that accompany immunosuppressive therapy for severe coronavirus disease 2019 (COVID-19). We report a fatal case of COVID-19 with disseminated mucormycosis diagnosed during autopsy. A 58-year-old man with diabetes was hospitalized for severe COVID-19 and treated with remdesivir, systemic steroids and tocilizumab. Following treatment, he was provided extracorporeal membrane oxygenation support. However, he died of multiple organ failure accompanied by pulmonary and kidney infarction, as revealed by computed tomography. Autopsy revealed that the infarction was caused by thromboangiitis due to mucormycosis in the brain, lungs, heart, liver and kidneys. Therefore, the diagnosis of disseminated mucormycosis was established. Disseminated mucormycosis is a rare complication of COVID-19. Although its early diagnosis is difficult, the disease progresses rapidly. Hence, we propose that immunosuppressive treatment for COVID-19 should be administered with caution considering the risk of developing severe opportunistic infections, such as mucormycosis.

Budd-Chiari syndrome caused by latent hepatic metastasis from a thymoma.

A 34-year-old woman visited our hospital because she had had abdominal bloating for 2 months. She had been diagnosed with invasive thymoma (WHO pathological type B2), for which she had undergone chemotherapy and total thymectomy 10 years previously. Six years previously, pleural dissemination was diagnosed and she had undergone right extra-pleural pneumonectomy. On presentation to our hospital, abdominal computed tomography and ultrasound scans revealed abundant ascites and a huge liver lesion, likely a metastasis from her thymoma, obstructing the inferior vena cava. The serum-ascites albumin gradient was high at 1.4 g/dL, which indicated portal hypertension. We diagnosed Budd-Chiari syndrome caused by liver metastasis from a previous thymoma. Steroid therapy resulted in shrinkage of her liver tumor and a marked decrease in her ascites. Although rare, Budd-Chiari syndrome caused by liver metastasis from a thymoma is a possible serious complication of advanced invasive thymoma.

Diagnostic accuracy of LAMP versus PCR over the course of SARS-CoV-2 infection.

OBJECTIVE: Reverse transcription loop-mediated isothermal amplification (RT-LAMP) has been validated to diagnose several viral infections. However, its diagnostic accuracy in detecting SARS-CoV-2 in real-life clinical settings remains unclear. This study aimed to determine the diagnostic sensitivity and specificity of RT-LAMP compared to reverse transcription-quantitative polymerase chain reaction (RT-qPCR) over the disease course of COVID-19. METHODS: A total of 124 nasopharyngeal swab samples obtained from 24 COVID-19 patients were tested by RT-LAMP and RT-qPCR. Sensitivities and specificities of RT-LAMP compared with RT-qPCR were analyzed as a function of time from onset. RESULTS: Up to the 9th day after onset, the RT-LAMP had a positivity of 92.8%, and the sensitivity and specificity compared with RT-qPCR was 100%. However, after the 10th day after onset, the positivity of RT-LAMP decreased to less than 25%, and the concordance of positivity between the two methods was below 60%. The limit of detection of RT-LAMP was 6.7 copies/reaction. CONCLUSIONS: Until the 9th day after the onset of symptoms, RT-LAMP had the same diagnostic accuracy as RT-qPCR. These findings suggest that RT-LAMP can be used as a diagnostic tool for COVID-19 as an alternative to RT-qPCR in the acute symptomatic phase of COVID-19.

A Prospective, Randomized, Open-Label Trial of Early versus Late Favipiravir Therapy in Hospitalized Patients with COVID-19.

Favipiravir is an oral broad-spectrum inhibitor of viral RNA-dependent RNA polymerase that is approved for treatment of influenza in Japan. We conducted a prospective, randomized, open-label, multicenter trial of favipiravir for the treatment of COVID-19 at 25 hospitals across Japan. Eligible patients were adolescents and adults admitted with COVID-19 who were asymptomatic or mildly ill and had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. Patients were randomly assigned at a 1:1 ratio to early or late favipiravir therapy (in the latter case, the same regimen starting on day 6 instead of day 1). The primary endpoint was viral clearance by day 6. The secondary endpoint was change in viral load by day 6. Exploratory endpoints included time to defervescence and resolution of symptoms. Eighty-nine patients were enrolled, of whom 69 were virologically evaluable. Viral clearance occurred within 6 days in 66.7% and 56.1% of the early and late treatment groups (adjusted hazard ratio [aHR], 1.42; 95% confidence interval [95% CI], 0.76 to 2.62). Of 30 patients who had a fever (≥37.5°C) on day 1, times to defervescence were 2.1 days and 3.2 days in the early and late treatment groups (aHR, 1.88; 95% CI, 0.81 to 4.35). During therapy, 84.1% developed transient hyperuricemia. Favipiravir did not significantly improve viral clearance as measured by reverse transcription-PCR (RT-PCR) by day 6 but was associated with numerical reduction in time to defervescence. Neither disease progression nor death occurred in any of the patients in either treatment group during the 28-day participation. (This study has been registered with the Japan Registry of Clinical Trials under number jRCTs041190120.).

Risk Factors of Infectious Complications After Endobronchial Ultrasound-Guided Transbronchial Biopsy.

BACKGROUND: Infectious complications after endobronchial ultrasound-guided transbronchial biopsy with a guide sheath (EBUS-GS-TBB) are serious in that they may delay or change scheduled subsequent therapy. The aim of this study was to identify risk factors for infection after EBUS-GS-TBB. RESEARCH QUESTION: What are the risk factors for infection after EBUS-GS-TBB? STUDY DESIGN AND METHODS: We retrospectively reviewed the medical records of 1,045 consecutive patients who had undergone EBUS-GS-TBB for peripheral lung lesions between January 2013 and December 2017 at Fujita Health University Hospital. We evaluated the following risk factors for infectious complications after EBUS-GS-TBB: relevant patient characteristics (age and comorbidities), lesion size, CT scan features of target lesion (intratumoral low-density areas [LDAs] and cavitation), stenosis of responsible bronchus observed by bronchoscopy, and laboratory data before EBUS-GS-TBB (WBC count and C-reactive protein concentration). RESULTS: Forty-seven of the study patients developed infectious complications (24 with pneumonia, 14 with intratumoral infection, three with lung abscess, three with pleuritis, and three with empyema), among whom the complication caused a delay in cancer treatment in 13 patients, cancellation of cancer treatment in seven patients, and death in three patients. Multivariate analysis showed that cavitation (P = .007), intratumoral LDAs (P < .001), and stenosis of responsible bronchus observed by bronchoscopy (P < .001) were significantly associated with infectious complications after EBUS-GS-TBB. Prophylactic antibiotics had been administered to 13 patients in the infection group. Propensity matched analysis could not show significant benefit of prophylactic antibiotics in preventing post-EBUS-GS-TBB infections. INTERPRETATION: Cavitation, LDAs for CT scan features of target lesions, and stenosis of responsible bronchus observed by bronchoscopy are risk factors of post-EBUS-GS-TBB infection. In the cohort, prophylactic antibiotics failed to prevent infectious complications.

A framework of generating explanation for conceptual understanding based on "semantics of constraints".

In science education, conventional problem practice hardly helps students reach "conceptual understanding" with which they can solve various problems by making appropriate models of target systems. Students often superficially read the solution of a problem and apply it wrongly to others without understanding the model. It is difficult to teach how to make appropriate models because model-making expertise includes a lot of implicit knowledge. In this paper, we propose a general framework for systematically describing such knowledge, which makes it possible not only to explain various models and the difference between them but also to design/sequence a set of problems appropriate for promoting conceptual understanding. Our framework was proved useful through a preliminary experiment in which the explanations generated based on our framework promoted subjects' (15 graduates and undergraduates) conceptual understanding in mechanics. The framework can be the basis for designing intelligent tutoring systems which explicitly help students reach conceptual understanding.