AZD-1222

Author Information

An event is serious (based on the ICH definition) when the patient outcome is:

• * death

• * life-threatening

• * hospitalisation

• * disability

• * congenital anomaly

• * other medically important event

A 36-year-old woman developed haemophagocytic lymphohistiocytosis (HLH) after receiving AZD-1222 COVID-19 vaccine.

The woman with no previous medical history, presented to hospital with a sore throat, myalgia and fever. Nine days before the presentation, she had received the first dose of AZD-1222 vaccine [ChAdOx1 COVID-19 vaccination; Oxford-AstraZeneca; route and dosage not stated]. Three days after vaccination, she developed mild facial swelling, which was resolved with unspecified antihistamines. On day 5, she developed a fever and severe myalgia.

Hence, the woman received simple analgesia. However, her symptoms progressed, which resulted in hospitalisation. Her medication, travel, family or sexual histories were unremarkable. No allergies to foods, drugs or vaccines were reported. On admission, her vital signs were as follows: body temperature: 39.9°C, RR: 32 breaths per minute, HR: 137 beats per minute, BP: 104/65mm Hg and oxygen saturations: 97% on air. Her clinical examination showed mild right upper quadrant abdominal tenderness with hepatomegaly. No rash, synovitis or joint-swelling was observed. Electrocardiography revealed sinus tachycardia, and urine dip showed positive results for protein, haemoglobin and ketones. Her inflammatory markers were also elevated. Other laboratory findings were normal. Hence, she was treated with piperacillin/tazobactam, unspecified analgesia and fluids for suspected sepsis secondary to infection. On day 5 of admission, she remained tachypnoeic, tachycardic and pyrexial. She also developed pleuritic pain and a pericardial rub. Repeat blood test results showed increasing C-reactive protein, white cell count, neutrophils, marked hyperferritinaemia and deranged clotting with raised fibrinogen. The CT of the thorax, abdomen and pelvis showed gross hepatomegaly, small bilateral pleural effusions and moderate splenomegaly with no lymphadenopathy. Electrocardiography showed ST elevation in leads V1−2. Serial troponins were 162 ng/L and 154 ng/L. The bedside echocardiography and subsequent cardiac MRI findings were consistent with constrictive pericarditis. Thoracic ultrasound revealed simple bilateral anechoic pleural effusions. Based on findings, a presumptive diagnosis of a multi-system inflammatory disorder due to recent COVID-19 vaccination was made. Hence, she was treated with methylprednisolone, followed by prednisolone. Within 12h of treatment, her RR, pulse rate and body temperature became normal, along with improvement in laboratory findings. However, after 6 days, fever reoccurred, and she developed thrombocytopenia. Repeat septic screen showed a negative result, while bone marrow biopsy revealed a reactive picture. Her high 'H score' of 70−80% confirmed the diagnosis of secondary HLH. Hence, she received a 5-day course of immune globulin, which resulted in the resolution of fever and improvement in chest pain and myalgia. After 33 days of hospitalisation, she was discharged home with a weaning course of prednisolone.