“Vaccine‐induced immune thrombotic thrombocytopenia (VITT)—Update on diagnosis and management considering different resources”: Comment

Dear Editors,

Recently Journal of Thrombosis and Haemostatis (JTH) published the updated recommendations for diagnosis and management of vaccine‐induced immune thrombotic thrombocytopenia (VITT) considering different resources. ¹ VITT is a rare but severe immunological reaction to the non‐replicable adenoviral vector–based COVID‐19 vaccines. Extreme activation of platelets and the coagulation system leads to a high risk of death from venous or arterial thrombosis or secondary hemorrhage. Public and clinician awareness has reduced mortality of VITT in Europe, North America, and Australia. This recommendation was timely as in the majority of low‐ and middle‐income countries (LMICs) the ChAdOx1 COVID‐19 vaccine (AstraZeneca) is one of the most widely used COVID‐19 vaccines. The vaccination campaign is still ongoing in many LMICs.

The World Health Organization has developed a comprehensive document guiding diagnosis and management, “Guidance for clinical case management of thrombosis with thrombocytopenia syndrome (TTS) following vaccination to prevent coronavirus disease (COVID‐19); interim guidance 19 July 2021 (https://apps.who.int/iris/bitstream/handle/10665/342999/WHO‐2019‐nCoV‐TTS‐2021.1‐eng.pdf)” and updated guidelines are expected to be published within the second half of 2022.

A puzzling issue is that very few cases of VITT have been reported from LMICs. It is unresolved whether this is caused by differences in predisposition (i.e., due to different genetic backgrounds), preimmunization by pathogens other than SARS‐CoV2, or whether under‐recognition is a major cause.

Here we show, based on the personal experience of one of us, that under‐recognition is a major issue and ask the International Society on Thrombosis and Haemostasis community to continue their educational activities in LMICs regarding VITT:

On January 19th 2022, I took my third vaccine shot, this time it was ChAdOx1 nCoV2 (Astra Zeneca). The 1st and 2nd vaccine shots were Zinivac (also known as Sinovac, which is based on inactivated adenovirus). The following 2 days I did had fever, but no other adverse effects. [Comment AG: typical and harmless early vaccination reaction.] At day three, I had a certification in “Zumba,” danced and exercise for about eight straight hours. Also the following days, I was feeling great. On Wednesday, January 26th I started to have problems. My back was hurting, and I had a very hard time trying to move. I did take a pain killer. On Friday, January 28th I still was having pain, but now I had a strong headache and was feeling very bad. [Comment AG: typical time window for VITT 7–14 days after vaccination, probably splanchnic vein thrombosis, ² and pre‐VITT headache, ³ , ⁴ a medical emergency.] My physician diagnosed pain related with work stress and prescribed pain medication and physiotherapy. The next day petechia developed all over my body. My physician diagnosed an allergic reaction to pain medication. [Comment AG: VITT related thrombocytopenia, either by platelet factor 4 antibody mediated platelet activation, potentially worsened by immune thrombocytopenia due to vaccine induced platelet autoantibodies. ⁵ Petechia due to additional platelet inhibition by non‐steroidal anti‐inflammatories.] Then, I started to feel numbness in my legs. I thought it was a result of all exercise, or by sitting in front of the computer working for so long. That night, I found a media article about Astra Zeneca vaccine's secondary effects and the open online JTH recommendation on VITT. I urged my physician to determine my platelet count, which was strongly reduced. I was referred to a hematologist, all pain killers were stopped, and prednisone prescribed for idiopathic thrombocytopenic purpura, but the numbness in my legs and arms worsened. [Comment AG: neurological sequelae of cerebral vein sinus thrombosis.] The following days, without pain killers, were a nightmare. More physicians were looking at my case, but none was studying all information about adverse vaccine effects, even though they had already all the information about it, given by myself as a result of my internet research. Their response was “We do not believe this is your case, let's keep looking to find where it all comes from.” On Friday, February 4th I was having problems with my legs and arms; in fact, walking and moving was difficult. I did not feel the left side of my body. It seemed it was all asleep. They took me to the hospital. I kept persuading the physicians to read about vaccine side effects. Two days later I developed seizures and had been admitted to the intensive care unit, where they diagnosed cerebral vein sinus thrombosis and performed interventional thrombectomy from the cerebral vein sinus and started alternative anticoagulation. Six months after, I'm here, alive and well, still recovering with a lot of neuro‐muscular therapy. This is my story and I urge the Thrombosis and Hemostasis community to educate in their countries about VITT, if adenovirus vector‐based vaccines are still used.

AUTHOR CONTRIBUTIONS

All authors wrote the manuscript and contributed their experience. All authors approved the final version of the manuscript.

CONFLICTS OF INTEREST

None of the authors has to declare a conflict of interest in the context of this letter.