Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 and was declared a global pandemic by the World Health Organization on 11 March 2020. A definitive diagnosis of COVID-19 is made after a positive result is obtained on reverse transcription-polymerase chain reaction assay. In Singapore, rigorous contact tracing was practised to contain the spread of the virus. Nasal swabs and chest radiographs (CXR) were also taken from individuals who were suspected to be infected by COVID-19 upon their arrival at a centralised screening centre. From our experience, about 40% of patients who tested positive for COVID-19 had initial CXR that appeared "normal". In this case series, we described the temporal evolution of COVID-19 in patients with an initial "normal" CXR. Since CXR has limited sensitivity and specificity in COVID-19, it is not suitable as a first-line diagnostic tool. However, when CXR changes become unequivocally abnormal, close monitoring is recommended to manage potentially severe COVID-19 pneumonia.
Adult ; Betacoronavirus ; Clinical Laboratory Techniques ; Coronavirus Infections ; complications ; diagnosis ; diagnostic imaging ; Female ; Humans ; Lung ; diagnostic imaging ; Male ; Middle Aged ; Pandemics ; Pneumonia, Viral ; complications ; diagnostic imaging ; Radiography ; Sensitivity and Specificity

INTRODUCTION: The current gold standard for diagnosing interstitial lung disease (ILD) involves an ILD clinic evaluation, followed by discussion in a multidisciplinary meeting (MDM). However, there is a paucity of data on the impact of ILD MDMs on the diagnosis and management of ILDs in Southeast Asia. We studied the clinical impact of the ILD service on the diagnosis and management of ILDs at a university-affiliated tertiary hospital in Singapore. METHODS: A single-centre retrospective review was done on 97 consecutive patients referred for evaluation to the ILD service from March 2016 to August 2017. RESULTS: Mean age of the patients was 67 ± 11 years. Gender distribution was almost equal (52% male), with a majority of never-smokers (63%). Mean forced vital capacity (FVC) was 1.81 ± 0.66 L (66% ± 20% predicted). The three commonest referral diagnoses were ILD of uncertain classification (n = 38, 39%), connective tissue disease-associated ILD (CTD-ILD) (n = 24, 25%) and idiopathic pulmonary fibrosis (IPF) (n = 16, 17%). Following evaluation by the ILD service, there was a change of diagnosis in 60 (62%) patients and a change of management in 71 (73%) patients. The majority of consensus MDM diagnoses were IPF (n = 35, 36%), CTD-ILD (n = 30, 30%) and others (n = 15, 15%). There was a significant prognostic separation between the IPF and non-IPF diagnoses made following evaluation by the ILD service. CONCLUSION The ILD service allowed for more precise subtyping of various ILDs. This is particularly useful for IPF patients, who can benefit from antifibrotic therapies.