Figure 1. a. CT-scan, Hypodensity in MCA territory. B. DSA, Rt ICA occlusion. C. Trans thoracic echocardiography, a large aortic arch thrombus.

Second case presentation:

A previously healthy 34-year-old, non-smoker, Asian man was admitted to hospital with sudden onset right hemiparesis along with Broca’s aphasia (Table 1). Twelve days prior, he had developed symptoms of anosmia, malaise and cough. His oropharyngeal swab for COVID-19 by qualitative RT-PCR was positive. At his arrival his brain CT-scan showed hypodensity within Left ACA and MCA territory (fig 2.a), and there was no time for clot retrieval treatment. His Magnetic Resonance Imaging of brain demonstrated a true diffusion restriction within ACA and MCA territory (fig 2.b, c). He was commenced on dual antiplatelet therapy, with Aspirin 100 mg daily and Clopidogrel 75 mg daily and Atorvastatin 80 mg daily. He then underwent carotid Doppler ultrasonography that showed an acute left ICA complete occlusion due to an intraluminal thrombosis of 5.9x9.8-millimeter diameter (fig 2.d). His trans-thoracic and transesophageal echocardiography were unremarkable. He was then commenced on anti-thrombotic regime with Heparin infusion adjusted to 6-hourly PTT monitoring. This was however changed to Rivaroxaban 20mg daily. An acute rise in his serum creatinine level from 0.9 mg/dL to 4.6 mg/dL was detected on day 8th. Although his acute kidney injury (AKI) suggested to be secondary to an ATN due to Glomerulonephritis after renal consultation, kidney biopsy was not performed due to ongoing anticoagulation therapy to prove this. He received 1-gram intravenous methylprednisolone daily for 3 days. Kidney function subsequently improved. His Serum creatinine was 1.3 mg/dl at time of discharge. Kidney injury secondary to thromboembolic events, is one of the major complications of COVID-19 and is considered as a mortality factor. The possibility of sequential thromboembolic events in the absence of other known risk factors except for COVID infection urged us to run an extensive thrombophilia screen. Homocysteine level was found to be 62µmol/L. Therefore, MTHFR activity was examined by genetic testing and reveled a homozygous mutant for the MTHFR C677T polymorphism. Treatment continued with Rivaroxaban 20mg daily and atorvastatin 80mg daily, patient was discharged and lost to follow up.