Table 2.

Organ systems affected by COVID-19 in the acute phase and recommended assessment considerations for athlete and other personnel returning to sport environment.

Organ system	Acute complications associated with COVID-19	Potential implications for returning athletes/other personnel	Assessment and investigation considerations
Respiratory	Pneumonia- Lung abnormalities have been seen on CT chest of symptomatic and asymptomatic cases57, 122, 123 ARDS124	Reduced aerobic capacity and increased respiratory distress Potential persisting restrictive lung patterns and reduced diffusion capacity These long-term respiratory complications been reported follow previous coronavirus epidemics (SARS, MERS) in non-athlete populations119	Clinical assessment Graded exercise testing, VO2 max testing FBE, CRP, spirometry, lung ultrasound, chest X-ray, CT chest Respiratory review
Cardiovascular	Cardiomyopathy47 Myocarditis125 Pericardial effusion126 Arrythmias45, 125 Autoimmune mimicry of vasculitis and thrombosis49, 127	A return to exercise with underlying cardiac complications could be contraindicated for some120 Return to contact sports/trauma could be contraindicated for some Persisting inflammatory states	Clinical assessment 12-lead ECG, troponins, coagulation profile, CRP, echocardiogram, cardiac MRI D-dimer, ferritin, C-reactive protein, erythrocyte sedimentary rate Cardiology review
Neurological	Multiple symptoms and signs have been described66 Guillain–Barré syndrome128 Elevated D-dimer129, 130 Stroke131 Encephalopathy132	Currently unclear as the neurological sequalae from mild to moderate cases is yet to be elucidated Post intensive care syndrome	Clinical assessment FBE, D-dimer, MRI brain Neurology review
Gastrointestinal/hepatic	Deranged liver function tests (LFTs)133 Some acute COVID-19 cases present with gastrointestinal and respiratory symptoms	Consider COVID-19 in patients presenting with combined respiratory and gastrointestinal symptoms133 Increased risk from hepatically excreted medications	Clinical assessment LFTs Gastroenterology review
Renal	Acute renal impairment134	Persistent subclinical renal impairment could be a risk on returning to high intensity training.	Clinical assessment UECs, urine dipstick/specific gravity Renal review
Fatigue	Commonly associated with viraemia	Post-viral fatigue is known to occur following other viral infections135 and may occur with COVID-19	Monitoring of self-report measures, fatigue symptoms and training loads
Mental health	Symptoms of depression and anxiety114 Both were more common in patients with less social support113	Potential increased risk of post-traumatic stress disorder (PTSD), depression, anxiety120 Persistent depression and anxiety have been reported following previous coronavirus epidemics in non-athletic populations	Clinical assessment Screening questionnaires Psychology review and psychiatrist review