Differential Diagnosis of COVID-19: Importance of Measuring Blood Lymphocytes, Serum Electrolytes, and Olfactory and Taste Functions.

Coronavirus disease 2019 (COVID-19) is associated with various symptoms and changes in hematological and biochemical variables. However, clinical features, which can differentiate COVID-19 from non-COVID-19, are not clear. We therefore examined the key clinical features of COVID-19 and non-COVID-19 patients. This study included 60 COVID-19 patients and 100 non-COVID-19 patients, diagnosed by PCR, and no significant differences in the age and sex were seen between the two groups. The frequencies of fatigue, loose stool, diarrhea, nasal obstruction, olfactory dysfunction, taste dysfunction, underlying hyperlipidemia, and the prescription of angiotensin II receptor blocker (ARB) were significantly higher in COVID-19 patients than those in non-COVID-19 patients. The counts of leucocytes, neutrophils, lymphocytes, eosinophils, monocytes, and basophils and the levels of chloride and calcium in blood of COVID-19 patients were significantly lower than those of non-COVID-19 patients. The frequencies of atypical lymphocytes and the levels of lactate dehydrogenase (LDH) and potassium were significantly higher in COVID-19 than those in non-COVID-19. The C-reactive protein (CRP) level in COVID-19 patients was significantly lower than that in non-COVID-19 patients, when we compared CRP levels among patients with elevated CRP. This study is the first to indicate that electrolyte levels and the frequency of atypical lymphocytes in COVID-19 are significantly different from those in non-COVID-19. Fatigue, loose stool, diarrhea, nasal obstruction, olfactory dysfunction, and taste dysfunction were the key symptoms of COVID-19. Furthermore, hyperlipidemia and ARB may be risk factors of COVID-19. In conclusion, leucocytes, leucocyte fractions, CRP, LDH, and electrolytes are useful indicators for COVID-19 diagnosis.

iMAP™ imaging of tumorous lesions surrounding the coronary arteries in a patient with an elevated serum level of immunoglobulin G4.

A 76-year-old woman with multiple coronary risk factors was admitted to our hospital because of episodes of new-onset chest pain that had begun 3 days previously. She underwent percutaneous coronary intervention (PCI) for severe stenoses in the two high lateral (HL) branches. Intravascular ultrasound (IVUS) revealed massive stenotic lesions in the HL branches and tumorous nonstenotic lesions in the left anterior descending coronary artery (LAD) and the left circumflex coronary artery (LCx). iMAP™, optical coherence tomography (OCT), and coronary computed tomography angiography (CCTA) were performed. iMAP depicted fibrosis in the vessel (green areas) and nonfibrotic tissue change suggestive of inflammation outside the vessel (yellow/red areas). OCT revealed high-intensity homogenous intimal hyperplasia with superficial calcification, and CCTA showed massive periarterial soft lesions in the HL, LAD, and LCx. The serum IgG4 level was high at 252-427 mg/dL (8 measurements) (reference range, 4.8-105.0 mg/dL). We suspected IgG4-related coronary periarteritis on the basis of the comprehensive diagnostic criteria as a possible diagnosis. The clinical course was good after initial and subsequent PCIs for both the HL stenoses and the progressing LCx stenosis, and there was no recurrence of angina pectoris thereafter. Steroids were not administered because the massive lesions did not enlarge during the 16 months of follow-up. iMAP was able to evaluate the tissue characteristics of tumorous lesions in the stenosed HL branches and the nonstenotic LAD and LCx in a patient with an elevated level of IgG4.

Intravascular Images of Coronary Stenosis with Multiple Channels in a Patient with Antiphospholipid Syndrome: The Optical Coherence Tomography Findings.

Intravascular images of coronary stenosis by antiphospholipid syndrome (APS) would be beneficial to understand the mechanism of this disease. A 59-year-old woman with APS/systemic lupus erythematosis (SLE) underwent emergent coronary angiography which revealed stenosis with micro channels in the proximal left anterior descending artery. According to optical coherence tomography (OCT), the central lumen was surrounded by a thick septum with a homogenous and high intensity. Multiple small channels existed near the vessel wall with diffuse intimal hyperplasia. White thrombi were floating distal to the stenosis. Intravascular images obtained by optical coherence tomography (OCT) revealed the microstructure of complex coronary stenosis, which had ambiguous findings on angiography and intravascular ultrasound (IVUS) in an acute coronary syndrome (ACS) patient with APS/SLE.

Resolution of left ventricular thrombus secondary to tachycardia-induced heart failure with rivaroxaban.

A 42-year-old man was admitted to our hospital because of lumbago and tachycardia-induced heart failure. Transthoracic echocardiography revealed impaired left ventricular function and a ball mass of thrombus in the left ventricle (LV). He was found to have systemic embolism in the spleen, kidneys, brain, and limbs. The patient was treated with limb thrombectomy followed by anticoagulation. Seven days after the direct factor Xa inhibitor, rivaroxaban, was initiated, transthoracic echocardiography was repeated, revealing disappearance of the LV thrombus without any clinical signs of cardiogenic embolism. His heart failure responded well and the LV wall motion had improved. This case suggests rivaroxaban has fibrinolytic effects on thrombi even in the LV.