Case presentation:
A 69-year-old man was hospitalized with febrile dyspnea at the military hospital of Antananarivo. He reported a close contact with a confirmed case of COVID-19 5 days before the onset of symptoms. His history included hypertension treated with Losartan 100mg per day, type 2 diabetes treated with Metformin 1500mg/day, alcoholism and smoking cessation for 10 years (9.5 pack-years). He has no known history of peripheral artery disease. For 13 days prior to his admission, he presented with a dry cough, shortness of breath at rest without orthopnea, fever, asthenia and anorexia. Two days before hospitalization, he felt a spontaneous severe pain with swelling of the left lower limb. Physical examination revealed a body mass index of 28.7 kg/m2, a pulsed oxygen saturation of 72% on room air, a respiratory rate of 23 per minute, a high temperature of 38.9°C, a heart rate of 117 beats per minute, a blood pressure of 135/80 mmHg and bilateral clinical signs of pneumonia. He presented a cyanosis of the left foot up to the mid-thigh (Figure 1), a hypoesthesia of the left lower limb and the skin was cool. The left pedal, posterior tibial, popliteal and femoral pulses were abolished.
The nasopharyngeal swab for SARS-CoV-2 reverse transcriptase-polymerase chain reaction (rt-PCR) performed on admission was negative. The complete blood count showed a haemoglobin level of 13.3 g/dl (13.5-17.5 g/dl) a white blood cells count of 11.81 G/L (5-10 G/L) and a platelet count of 81 G/L (150-400 G/L). The C-reactive protein was 82.6 mg/L (<6 mg/l). The creatinine was 187 µmol/L (65.4-119.3 µmol/L). The blood sodium level was 141 mmol/L (135-145 mmol/l) and the blood potassium level was 4.9 mmol/L (3.6-5.2 mmol/l). The glycated haemoglobin was 7.5% (<6%). The D-dimer was 514 times the upper normal limit (220-500 ng/mL). The troponin was normal. The electrocardiogram showed a regular tachycardia with a heart rate of 103 bpm. Chest CT scan was in favour of COVID-19 showing ground glass images with 50-75% involvement, without pulmonary embolism (Figure 2). The arterial doppler ultrasound showed an extensive intraluminal thrombus along the arterial axes of the left lower limb, completely obstructing them, starting from the common iliac artery just after its bifurcation with the aorta and extending distally (external iliac, common femoral, superficial femoral, popliteal, anterior tibial, posterior tibial, fibular and pedal), without any detectable collateral circulation (Figure 3 a, b, c). The patient was diagnosed with a severe COVID-19 associated with acute ischemia of the whole left lower limb secondary to an extensive arterial thrombosis. He was receiving oxygen therapy with a high concentration oxygen mask at 15 L/min, corticosteroid therapy with intravenous dexamethasone (12 mg/day), subcutaneous therapeutic anticoagulation with enoxaparin at a curative dose (8000UI x2/day), oral antibiotic therapy with levofloxacin (1g/day) and insulin therapy (rapid-acting insulin 14UI x3/day and long-acting insulin 20 UI/day). The patient was transferred to the surgical ward due to aggravation of the ischemia with skin necrosis of extremities and underwent an amputation of the ischemic left lower limb. The post-operative follow-up was simple. The patient was discharged after 28 days of hospitalization and was under long-term oxygen therapy at home. At one month follow-up, he remained well and there was no recurrence of other ischemia.