Risk factors for clinically significant diffuse parenchymal lung abnormalities persisting after severe COVID-19 pneumonia

Background & objectives: The risk factors for clinically significant diffuse parenchymal lung abnormalities (CS-DPLA) persisting after severe coronavirus disease 2019 (COVID-19) pneumonia remain unclear. The present study was conducted to assess whether COVID-19 severity and other parameters are associated with CS-DPLA. Methods: The study participants included patients who recovered after acute severe COVID-19 and presented with CS-DPLA at two or six month follow up and control group (without CS-DPLA). Adults volunteers without any acute illness, chronic respiratory illness and without a history of severe COVID-19 were included as healthy controls for the biomarker study. The CS-DPLA was identified as a multidimensional entity involving clinical, radiological and physiological pulmonary abnormalities. The primary exposure was the neutrophil-lymphocyte ratio (NLR). Recorded confounders included age, sex, peak lactate dehydrogenase (LDH), advanced respiratory support (ARS), length of hospital stay (LOS) and others; associations were analyzed using logistic regression. The baseline serum levels of surfactant protein D, cancer antigen 15-3 and transforming growth factor-? (TGF-?) were also compared among cases, controls and healthy volunteers. Results: We identified 91/160 (56.9%) and 42/144 (29.2%) participants with CS-DPLA at two and six months, respectively. Univariate analyses revealed associations of NLR, peak LDH, ARS and LOS with CS-DPLA at two months and of NLR and LOS at six months. The NLR was not independently associated with CS-DPLA at either visit. Only LOS independently predicted CS-DPLA at two months [adjusted odds ratios (aOR) (95% confidence interval [CI]), 1.16 (1.07-1.25); P<0.001] and six months [aOR (95% CI) and 1.07 (1.01-1.12); P=0.01]. Participants with CS-DPLA at six months had higher baseline serum TGF-? levels than healthy volunteers. Interpretation and conclusions: Longer hospital stay was observed to be the only independent predictor of CS-DPLA six months after severe COVID-19. Serum TGF-? should be evaluated further as a biomarker.

A concise review of diagnosis and evaluation of interstitial lung abnormalities / 中华劳动卫生职业病杂志

Interstitial lung abnormalities (ILAs) refer to the subtle or mild signs of ILAs pulmonary parenchyma on chest HRCT scans, which are not yet sufficient to diagnose a certain interstitial lung disease, may be potentially compatible an early stage of the diseases. The signs of ILAs usually includes ground-glass opacities, reticular abnormakicies, honeycombing, traction bronchiectasis or non-emphysematous cysts. This article reviews the research progreses in the definition and classification, risk factors, prognosis, comorbidities and management of ILAs in combination with domestic and foreign literatures.

Persistent interstitial lung abnormalities in post-COVID-19 patients: a case series

A new concept of multisystem disease has emerged as a long-term condition following mild-severe COVID-19 infection. The main symptoms of this affection are breathlessness, chest pain, and fatigue. We present here the clinical case of four COVID-19 patients during hospitalization and 60 days after hospital discharge. Physiological impairment of all patients was assessed by spirometry, dyspnea score, arterial blood gas, and 6-minute walk test 60 days after hospital discharge, and computed tomographic scan 90 days after discharge. All patients had fatigue, which was not related to hypoxemia or impaired spirometry values, and interstitial lung alterations, which occurred in both mechanically ventilated and non-mechanically ventilated patients. In conclusion, identifying the prevalence and patterns of permanent lung damage is paramount in preventing and treating COVID-19-induced fibrotic lung disease. Additionally, and based on our preliminary results, it will be also relevant to establish long-term outpatient programs for these individuals.