Three years follow-up report of two diffuse connective tissue disease cases caused by SARS-CoV-2 infection / 中国热带医学

@#Abstract: To report on two patients with Coronavirus Disease 2019 (COVID-19) combined with diffuse connective tissue disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection followed for nearly 3 years, in order to understand the long-term effects on the patients' immune system. Both patients were male, aged 81-82 years, and were hospitalized with fever on January 29, 2020 and February 10, 2020, respectively. Both were diagnosed with COVID-19 after positive SARS-CoV-2 polymerase chain reaction (PCR) tests. After receiving anti-infection treatment, cough suppressants, ex‐pectorants, and symptomatic supportive treatment, their body temperature returned to normal and two consecutive PCR tests were negative for SARS-CoV-2, and they were discharged from hospital. However, due to recurring fevers and varying degrees of rheumatic disease-related symptoms, both patients were readmitted to the hospital, indicating the presence of positive auto‐ antibodies and organ involvement. One patient recovered from COVID-19 with recurrent fever, joint pain, muscle aches and subcutaneous nodules, and was subsequently diagnosed with undifferentiated connective tissue disease. The other patient developed recurrent fever, mouth ulcers and rash after recovery from COVID-19 and was subsequently diagnosed with anti neutro phil cytoplasm antibody (ANCA)-associated vasculitis (AAV). The patient was treated with glucocorticoids and immunosuppres sive drugs and the symptoms resolved rapidly and subsequent laboratory and imaging examinations showed stable condition. However, due to self-termination of medication, their symptoms quickly relapsed, and further treatment with glucocorticoids and immunosuppressive agents resulted in sustained stability of their condition. The erythrocyte sedimentation rate and hyper‐sensitive C-reactive protein remained within normal limits, and lung CT scans showed stable lesions with partial absorption.SARS-CoV-2 infection may have long-term effects on patients' immune systems, leading to abnormal immune responses and diffuse connective tissue disease. This suggests that regular follow-up observation of immune system-related diseases may be necessary for elderly patients with COVID-19.

Relatively Increased Number of Liver Foxp3+ Regulatory T Cells against Hepatic Lesions in Murine Lupus / 华中科技大学学报（医学）（英德文版）

Systemic lupus erythematosus (SLE) is a multiple organ autoimmune disorder,including theliver,but the possible reason in impairment in the liver is still unclear.Our present study assessed alterations of transcription factor Foxp3+ regulatory T cells (Tregs) and several other immune molecules [programmed cell death 1 and its ligand (PD1 and PD-L1),and interleukin 10 (IL-10) and transform growth factor β (TGF-β)] in the liver and other major organs of lupus-prone BXSB mice by flow cytometry,real-time quantitative reverse trinscription PCR,and enzyme-linked immunosorbent assay.Results showed that both frequency and number of Foxp3+ Tregs were dramatically reduced in the thymus,spleen and kidney of the BXSB mice (P＜0.05),but those in the liver were kept in nearly normal range,when compared to negative control C57BL/6 mice.In comparison to control mice,the mRNA levels of Foxp3,PD1 and PD-L1 were significantly decreased in the kidneys of BXSB mice (P＜0.05),but there was no significant difference in the livers of the BXSB mice (P＞0.05).Protein levels of IL-10 and TGF-β in serum showed no significant difference between BXSB and C57BL/6 mice,but were significantly increased in the kidneys and livers of BXSB mice as compared with those in C57BL/6 mice (P＜0.05).These results suggest that reduced Foxp3+ Tregs are involved in the pathogenesis of SLE in BXSB mice,and relatively higher number of these cells in the livers than in the other target organs could constitute a protective mechanism against hepatic lesions in lupus-prone mice,which may provide insights into development of new therapeutic approaches in SLE patients.

Identification of a New Lamin A/C Mutation in a Chinese Family Affected with Atrioventricular Block as the Prominent Phenotype / 华中科技大学学报（医学）（英德文版）

Even though mutations in LMNA have been reported in patients with typical dilated cardio-myopathy(DCM)and atrioventricular block(AVB)previously,the purpose of this study was to disclose this novel genetic abnormality in one Chinese family with the atypical phenotype of progressive AVB followed by DCM with normal QRS interval.Genome-wide linkage analysis mapped the AVB gene in this family to a marker at chromosome 1q21.2,where the LMNA gene was located.Direct DNA sequence analysis revealed a heterozygous G to A transition at nucleotide 244 in exon 1 of LMNA,which resulted in an E82K mutation.The E82K mutation co-segregated with all affected individuals in the family,and was not present in 200 normal controls.Further clinical evaluation of mutation carriers showed that 5 of 6 AVB patients exhibited mild DCM with a late onset of age in the fourth and fifth decades.Ejection fractions were documented in 5 patients with DCM,but 4 showed a normal value of ≥50%.Echocardiography showed that atrial dilatation occurred earlier than ventricular dilatation in the patients.This study suggests that progressive AVB with normal QRS interval and accompanying DCM at later stages may represent a distinct type of DCM.The molecular mechanism by which the E82K mutation causes AVB as the prominent phenotype in DCM may be a focus of future studies.