The observed clinical phenomena and outcomes
| Clinical syndrome | Patients (n) | Treatment | Outcome |
| Distal digital thrombosis | 3 | Prostacyclin in one case. Bosentan in other cases. Oral prednisolone in all patients with 3 months of anticoagulation. | Prostacyclin was ineffective for halting progress of ischaemia while bosentan was very effective. The one on prostacyclin later developed thromboembolic pulmonary hypertension despite apixaban and died from complications. |
| Cerebral vasculitis: imbalance and cognitive deficit | 2 | Intravenous methylprednisolone in both. Intravenous immunoglobulin induction with azathioprine maintenance in one patient and intravenous cyclophosphamide induction with MMF maintenance in the other. | Full recovery to baseline with no new lesions on follow-up MRI. |
| De novo inflammatory arthritis: seropositive rheumatoid arthritis (n=2), peripheral spondyloarthritis (n=6) | 8 | All patients relapsed on stopping initial prednisolone or NSAIDs with persistent symptoms beyond 3 months, needing DMARDs. | All achieved remission. |
| Worsening of previously diagnosed autoimmune rheumatological conditions: SLE (n=2), rheumatoid arthritis (n=2), peripheral spondyloarthritis (n=1) | 5 | 4 out of 5 were in long-term remission with good drug compliance. One patient with SLE had active disease with intermittent flares but in remission for 7 months preceding vaccination. All patients needed escalation of immunosuppression. | All achieved remission. |
| Cutaneous vasculitis with inflammatory oligoarthritis (positive ANA) | 1 | Leflunomide (intolerance of methotrexate). | Achieved remission. |
| Isolated cutaneous vasculitis | 1 | Prolonged course of tapering prednisolone 0.5 mg/kg/day. | Achieved remission. |
| Severe autoimmune haemolytic anaemia with positive ANA | 1 | Intravenous methylprednisolone effective but relapse on oral prednisolone. Remission induction with rituximab. Maintenance with hydroxychloroquine. | Achieved remission. |
| Unusual cognitive symptoms with positive ANA: dissociation and paraesthesia | 1 | Moderate-dose prednisolone tapered over 3 weeks. | Achieved remission without sequela. |
| RS3PO-like picture | 1 | Prednisolone, methotrexate, leflunomide. | Unable to completely stop steroids. Remission with 2 DMARDs and prednisolone 5 mg every other day. |
| Complex picture of digital ischaemia, cutaneous vasculitis and mucosal ulceration | 1 | Prednisolone, warfarin, bosentan. | CMV serology negative. Digital ischaemia stopped progression rapidly with bosentan. Remission with cessation of all medications after 1 year of treatment. Lost 4 digits. |
ANA, antinuclear antibody; CMV, cytomegalovirus; DMARDs, disease-modifying antirheumatic drugs; MMF, mycophenolate mofetil; NSAIDs, non-steroidal anti-inflammatory drugs; RS3PO, remitting seronegative symmetrical synovitis with pitting oedema; SLE, systemic lupus erythematosus.