Predicting lung fibrosis in post-COVID-19 patients after discharge with follow-up chest CT findings

Abstract

Background Coronavirus disease has spread widely all over the world since the beginning of 2020, and this required rapid adequate management. High-resolution computed tomography (HRCT) has become an initial valuable tool for screening, diagnosis, and assessment of disease severity. This study aimed to assess the clinical, radiographic, and laboratory findings of COVID-19 with HRCT follow-up in discharged patients to predict lung fibrosis after COVID-19 infection in survived patients. Results This study included two-hundred and ten patients who were tested positive for the novel coronavirus by nasopharyngeal swap, admitted to the hospital, and discharged after recovery. Patients with at least a one-time chest CT scan after discharge were enrolled. According to the presence of fibrosis on follow-up CT after discharge, patients were classified into two groups and assigned as the “non-fibrotic group” (without evident fibrosis) and “fibrotic group” (with evident fibrosis). We compared between these two groups based on the recorded clinical data, patient demographic information (i.e., sex and age), length of stay (LOS) in the hospital, admission to the ICU, laboratory results (peak C-reactive protein [CRP] level, lowest lymphocyte level, serum ferritin, high-sensitivity troponin, d-dimer, administration of steroid), and CT features (CT severity score and CT consolidation/crazy-paving score). CT score includes the CT during the hospital stay with peak opacification and follow-up CT after discharge. The average CT follow-up time after discharge is 41.5 days (range, 20 to 65 days). There was a statistically significant difference between both groups (p ˂0.001). Further, a multivariate analysis was performed and found that the age of the patients, initial CT severity score, consolidation/crazy-paving score, and ICU admission were independent risk factors associated with the presence of post-COVID-19 fibrosis (p<0.05). Chest CT severity score shows a sensitivity of 86.1%, a specificity of 78%, and an accuracy of 81.9% at a cutoff point of 10.5. Conclusion The residual pulmonary fibrosis in COVID-19 survivors after discharge depends on many factors with the patient’s age, CT severity, consolidation/crazy-paving scores, and ICU admission as independent risk factors associated with the presence of post-COVID-19 fibrosis.

Post COVID-19 pulmonary fibrosis; a meta-analysis study

“…In our study, the mean age of the fibrotic patients was much higher (59 years) than that of those with no fibrotic changes (48.5 years). Most of the available literature shared similar findings regarding this aspect [ [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] ]. However, Aul et al reported that the age difference was insignificant between the fibrotic and non-fibrotic patients [ 21 ].…”

“…Previous reports, without dispute, have highlighted the severity of COVID-19 as a risk factor for PCPF development. The reported severity factors include invasive and non-invasive mechanical ventilation, a CT score of more than 18, ICU admission, and a longer hospitalization period [ [21] , [22] , [23] , [24] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] ]. The same findings were observed in this meta-analysis.…”

“…Aul et al reported a low prevalence of 9.3% [ 21 ]. Meanwhile, the rest of the available studies have reported a much higher prevalence, ranging from 25.5% to 84.15% [ [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] , [33] ], with the highest being reported by Zou and associates [ 31 ].…”

“…The literature has had contradictory findings regarding the effect of gender and smoking status on the development of fibrosis. Despite some studies suggesting a higher prevalence of PCPF in males [ 21 , 22 , 25 , 26 ], the majority of the studies disregard it [ 23 , 24 , [27] , [28] , [29] , [30] , [31] , [32] , [33] ]. Multiple studies consider smoking as a risk factor for PCPF [ 21 , 22 , 25 ]; meanwhile, others do not highlight this connection [ 26 , 32 ].…”

Long-Term Outcomes of Patients with Coronavirus Disease 2019 at One Year after Hospital Discharge

“…Findings of pulmonary fibrosis were confirmed via HRCT in a proportion of our patients with persistent dyspnea after recovery from acute COVID-19. Residual pulmonary fibrosis in HRCT has been found in up to half of COVID-19 survivors after discharge [57], its severity mainly depending on the patient's age, comorbidities, and length of ICU stay [58]. Finally, diabetes onset or a worsening in glycemic control was documented in 1.3% and 10.1% of patients, respectively.…”