Are there any specific investigations that should be conducted in patients with recurrent or severe chilblains?

In patients presenting with recurrent or severe chilblains, specific investigations should be considered to exclude underlying systemic or vascular conditions. Initial assessment typically includes a thorough clinical history and examination to identify any associated autoimmune symptoms or signs of connective tissue disease, as chilblains can be secondary to such disorders.

Blood tests should include a full blood count, inflammatory markers (such as ESR and CRP), and autoimmune serology including antinuclear antibodies (ANA) and extractable nuclear antigen (ENA) panel to screen for lupus erythematosus or other connective tissue diseases.

Additionally, assessment for cryoglobulins and cold agglutinins may be warranted to exclude cryoglobulinaemia or cold agglutinin disease, which can present with similar acral symptoms.

Vascular investigations such as Doppler ultrasound may be indicated if peripheral arterial disease is suspected, especially in patients with risk factors or atypical presentations.

Capillaroscopy can be useful to evaluate microvascular changes, particularly to differentiate primary chilblains from those associated with systemic sclerosis or other vasculopathies.

These recommendations align with UK clinical practice guidelines that emphasize exclusion of secondary causes in atypical or severe cases ¹. Recent literature further supports this approach, highlighting the importance of autoimmune screening and vascular assessment to guide management and identify patients who may benefit from targeted therapies (Sharifzadeh and Smith, 2025).