To investigate the correlation between the infection status of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 8 (HHV-8) and the disease severity and prognosis of patients with idiopathic pulmonary fibrosis (IPF).

Seventy-nine IPF patients admitted to our hospital from January 2020 to December 2024 were selected as subjects. Based on the percentage of predicted forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO), as well as clinical manifestations, they were divided into a mild group 41 cases, a moderate group 24 cases, and a severe group (14 cases). Real-time fluorescent quantitative PCR was used to detect the serum nucleic acid load of CMV, EBV, and HHV-8. Follow-up was conducted via outpatient visits to compare the differences in virus positivity rates and nucleic acid loads among patients with different disease severities and prognoses. Pearson correlation analysis was used to analyze the association between viral load and disease condition/prognosis. The predictive value of viral load for prognosis was assessed using receiver operating characteristic (ROC) curve analysis.

The FVC (% predicted) values for the mild, moderate, and severe groups were (78.86±8.15), (60.25±6.71), and (42.25±4.89), respectively; the DLCO(% predicted) values were (61.15±6.37), (45.52±4.78), and (31.15±4.18), respectively (P<0.001). The CMV positivity rates in the mild, moderate, and severe groups were 9.76%, 37.50%, and 71.43%, respectively. The nucleic acid loads of CMV, EBV, and HHV-8 were positively correlated with the severity of IPF (r=0.562, 0.625, 0.482, P<0.001). Sixty-two survivors(78.48%), while 17 deaths (21.52%). The viral loads in deceased patients [CMV (4 112.25±705.51) copies/ml, EBV (36 412.15±3 348.84) copies/ml, HHV-8(389.95±35.56) copies/ml] were higher than those in surviving patients [CMV (845.51±145.56) copies/ml, EBV (8 847.15±1 521.15) copies/ml, HHV-8 (122.25±25.56) copies/ml]. Viral load was positively correlated with poor prognosis (r=0.612, 0.665, 0.567, P<0.001). ROC curve analysis showed that the combined detection of the three viral infection statuses for predicting IPF prognosis had an area under the curve (AUC) of 0.823, with a sensitivity of 94.12% and a specificity of 87.30%.

The infection status of CMV, EBV, and HHV-8 is significant for evaluting the disease severity and prognosis of IPF patients.