Table 2

Tabulation of previous studies for comparison

Previous studies	Radwi and Farsi7	Cittone et al8			Lemoine et al9	Gutierrez-Nunez and Torres10
Location	Middle East (Saudi arabia)	Europe (Switzerland)			North America	Country of occurrence not stated. (Author’s communication details not available)
Age	69	85	86	72	70	43
Gender	Male	Male	Female	Female	Male	Female
Comorbid	Diabetes mellitus Hypertension History of prostate adenocarcinoma in remission (done prostatectomy and radiation	Hypertension Coronary artery bypass graft Peripheral artery disease Renal and carotid artery stenosis	Moderate to severe aortic valve stenosis, Third-degree atrioventricular block on pacemaker	Multiple comorbidities including arterial disease	Polymyalgia rheumatica Hepatitis C virus with spontaneous clearance	–
Type of vaccine	Pfizer mRNA	Moderna (mRNA-1273)	Moderna COVID-19 (mRNA-1273)	Moderna COVID-19 (mRNA-1273)	Moderna COVID-19 (mRNA-1273)	Pfizer mRNA
Total dose received	Two doses	Two doses	Two doses	One dose	One dose	Two doses
Onset of symptoms	Nine days after the first dose, the patient developed a spontaneous mild bruise over the left wrist. After the second dose, the patient developed spontaneous ecchymosis on the left forearm and elbow, ecchymosis on the right thigh (after intramuscular injection and minor trauma), and left anteromedial thigh intramuscular haematoma.	One week after the first dose, the patient developed right forearm and right thigh haematoma, with bilateral knee haemarthrosis. After the second dose, the patient developed a large haematoma of the right iliopsoas muscle and free fluid in the right lower abdomen.	Three weeks after the second dose, the patient had a fall with a right-sided haemothorax and fractures of the 9th, 10th and 11th ribs.	Two weeks after the first dose, the patient developed extensive cutaneous bruises. 24 days after the first dose, the patient developed multiple large cutaneous haematomas.	Eight days after the first dose, he developed extensive ecchymosis on the right upper limb, ecchymosis on the left forearm and right lower extremity.	Three weeks after the second dose, the patient developed bilateral extremities haematomas.
aPTT (sec)	115.2	49	Not stated.	184	57.5	86.1
FVIII level	1% → 5%	Not detectable	23% → 178%	Not detectable → 5% (after the third dose of rituximab)	0.03 IU/mL	<5%
FVIII inhibitor titre (BU)	80 → 2	2.2	1.01	12.4 → 5.6 (after the third dose of rituximab)	39.9	78.4
Use of aPCC/ rFVIIa	–	rFVIIa and aPCC	rFVIIa and aPCC	rFVIIa for 7 days	rFVIIa and aPCC	–
Treatment	Oral prednisolone 1 mg/kg daily for 4 weeks	Oral prednisolone 100 mg daily Rituximab Arterial coiling	Oral prednisolone 1 mg/kg daily for seventeen days Chest drain for right haemothorax	Oral prednisolone 100 mg daily Rituximab 375 mg/m2 weekly (Four doses) Tranexamic acid	Oral prednisone 1 mg/kg daily Cyclophosphamide 2 mg/kg daily	Intravenous rituximab Intravenous methylprednisolone.
Outcome	Good	The patient had an acute gallbladder rupture with active arterial bleeding and passed away.	Good	Good	Good	Not stated.

aPCC, activated prothrombin complex concentrate; aPTT, activated partial thromboplastin time; FVIII, factor VIII; rFVIIa, recombinant activated factor VII.