Detection of respiratory viruses and expression of inflammatory cytokines in patients with acute exacerbation chronic obstructive pulmonary disease in Mongolia China / Detecção de vírus respiratórios e expressão de citocinas inflamatórias em pacientes com doença pulmonar obstrutiva crônica de exacerbação aguda na Mongólia, China

Chronic obstructive pulmonary disease (COPD) was estimated to be the third cause of global mortality by 2020. Acute exacerbation COPD (AECOPD) is a sudden worsening of COPD symptoms and could be due to virus/bacterial infections and air pollution. Increased expression of inflammatory markers in patients with AECOPD is associated with viral infection. This study aimed to detect different viruses and analyze the expression of various inflammatory markers associated with AECOPD patients. Three hundred and forty-seven patients diagnosed with COPD according to GOLD criteria were included in this study. Swab samples and blood were collected for the detection of viruses by RT-PCR and expression of inflammatory markers, respectively. Of the swab samples, 113 (32.6%) of samples were positive for virus detection. Of these, HRV (39.8%) was the predominant virus detected followed by FluB (27.4%) and FluA (22.1%). The presence of HRV was significantly higher (p=0.044) among the other detected viruses. When compared to healthy controls the expression levels of TNF-α, IL-6 and IL-8 were significantly higher (p<0.05) in virus-positive patients. The IL-6 and IL-8 were the next predominantly expressed in markers among the samples. The higher expression rate of IL-8 was significantly (p<0.05) associated with patients having COPD GOLD III severity level and smoking history. Although HRV was the predominant virus detected the combined prevalence of Influenza A and B surpassing the rate of HRV. The high-level expression of well known inflammatory markers of AECOPD, TNF-α, IL-6 and IL-8 indicates a chronic severe illness. These markers play an important role and could be used as a marker for determining the severity of AECOPD.

Estima-se que a doença pulmonar obstrutiva crônica (DPOC) seja a terceira causa de mortalidade global em 2020. A exacerbação aguda DPOC (AECOPD) é um agravamento súbito dos sintomas da DPOC e pode ser devido a infecções por vírus/bactérias e poluição do ar. O aumento da expressão de marcadores inflamatórios em pacientes com AECOPD está associado à infecção viral. Este estudo teve como objetivo detectar diferentes vírus e analisar a expressão de vários marcadores inflamatórios associados a pacientes com AECOPD. Trezentos e quarenta e sete pacientes com diagnóstico de DPOC de acordo com os critérios GOLD foram incluídos neste estudo. Amostras de swab e sangue foram coletadas para detecção de vírus por RT-PCR e expressão de marcadores inflamatórios, respectivamente. Das amostras de esfregaço, 113 (32,6%) amostras foram positivas para detecção de vírus. Nestas, o HRV (39,8%) foi o vírus predominante detectado, seguido do FluB (27,4%) e do FluA (22,1%). A presença de VFC foi significativamente maior (p = 0,044) entre os demais vírus detectados. Quando comparados a controles saudáveis, os níveis de expressão de TNF-α, IL-6 e IL-8 foram significativamente maiores (p <0,05) em pacientes com vírus positivo. A IL-6 e a IL-8 foram as próximas predominantemente expressas em marcadores entre as amostras. A maior taxa de expressão de IL-8 foi significativamente (p <0,05) associada a pacientes com grau de gravidade GOLD III da DPOC e história de tabagismo. Embora o HRV tenha sido o vírus predominante, a prevalência combinada de Influenza A e B ultrapassou a taxa de HRV. O alto nível de expressão de marcadores inflamatórios bem conhecidos de AECOPD, TNF-α, IL-6 e IL-8 indica uma doença crônica grave. Esses marcadores desempenham um papel importante e podem ser usados como um marcador para determinar a gravidade da AECOPD.

Etiología y biomarcadores de inflamación sistémica en las exacerbaciones leves a moderadas de la enfermedad pulmonar obstructiva crónica / Etiology and biomarkers of systemic inflammation in mild to moderate COPD exacerbations

Background: The etiology of acute exacerbations of chronic obstructive pulmonary disease (COPD) is heterogeneous and still under discussion. Inflammation increases during exacerbation of COPD. The identification of inflammatory changes will increase our knowledge and potentially guide therapy. Aim: To identify which inflammatory parameters increase during COPD exacerbations compared to stable disease, and to compare bacterial and viral exacerbations. Material and Methods: In 85 COPD patients (45 males, mean age 68 ± 8 years, FEV1 46 ± 17% of predicted) sputum, nasopharyngeal swabs and blood samples were collected to identify the causative organism, during a mild to moderate exacerbation. Serum ultrasensitive C reactive protein (CRP), fibrinogen and interleukin 6 (IL 6), neutrophil and leukocyte counts were measured in stable conditions, during a COPD exacerbation, 15 and 30 days post exacerbation. Results: A total of 120 mild to moderate COPD exacerbations were included. In 74 (61.7%), a microbial etiology could be identified, most commonly Mycoplasma pneumoniae (15.8%), Rhinovirus (15%), Haemophilus influenzae (14.2%), Chlamydia pneumoniae (11.7%), Streptococcus pneumoniae (5.8%) and Gram negative bacilli (5.8%). Serum CRP, fibrinogen and IL 6, and neutrophil and leukocyte counts significantly increased during exacerbation and recovered at 30 days post exacerbation. Compared to viral exacerbations, bacterial aggravations were associated with a systemic inflammation of higher magnitude. Conclusions: Biomarkers of systemic inflammation increase during mild to moderate COPD exacerbations. The increase in systemic inflammation seems to be limited to exacerbations caused by bacterial infections.