Table 1.

Brief summary of the demographic and clinical features of the patients.

Patient	Diagnosis	Sex	Age, years	Type of COVID‐19 vaccine	Time lag, days	Comorbidities	Clinical course
1	PRP	F	62	Moderna, first dose (second dose not administered)	5	Metabolic syndrome, T2DM, hypertensive heart disease, hypothyroidism, CKD	Progressive remission with systemic prednisone (1 mg/kg/day for 2 weeks, then tapered) and topical steroids at 1‐month follow‐up. Hospitalization for COVID‐19 infection 4 months after PRP onset
2	PRP	F	82	Pfizer–BioNTech, first dose (second dose not administered)	7	Plaque and nail psoriasis, CLL, T2DM, hypertension, COPD	Clinical improvement achieved with subcutaneous MTX 15 mg/weekly. Residual PP hyperkeratosis and scaly plaques on head and neck at the 4‐month follow‐up
3	SS	F	69	Oxford–AstraZeneca, first dose (second dose not administered)	12	Overweight, hypertension, dyslipidaemia, iron‐deficiency anaemia	Treated with steroid administration (prednisone 1 mg/kg/day for 4 weeks, then slow tapering). At 3‐month follow‐up, complete healing of the ulcerated plaques with residual hyperpigmentation
4	PLEVA	M	70	Pfizer–BioNTech, second dose	5	Acute lymphocytic leukaemia in complete remission	Treated with topical combination of fusidic acid 2% plus betamethasone cream 0.1%. Complete remission within 10 weeks
5	EM	F	76	Pfizer–BioNTech, first dose (second dose administered)	4	Lung adenocarcinoma (Stage IV), arterial hypertension, T2DM, COPD	Topical prescription of methylprednisolone 0.1% cream twice daily for 10 days. Complete clearance achieved in 10 days. No recurrence with the second vaccine dose

CKD, chronic kidney disease; CLL, chronic lymphocytic leukaemia; COPD, chronic obstructive pulmonary disease; EM, erythema multiforme; PLEVA, pityriasis lichenoides et varioliformis acuta; PP, palmoplantar; PRP, pityriasis rubra pilaris; T2DM, Type 2 diabetes mellitus; MTX, methotrexate; SS; Sweet syndrome.