Nailfold capillaroscopy, currently used to diagnosis scleroderma, dermatomyositis and antisynthetase myositis, appears to have some prognostic value as well.

According to a study of 152 patients from the South Australian Scleroderma Register between 1991 and 2015, nailfold capillary drop out was significantly associated with increased mortality.

Professor Peter Roberts-Thomson, from the immunology department at Flinders Medical Centre, told the limbic their findings were consistent with other evidence that the severity of the capillary abnormality was associated with disease outcome.

“The current study has shown that those who have damage to their nailfold capillaries – where they are destroyed we call that capillary drop out – the greater the damage, the more likely they are to die earlier.”

“Normally there are about 10-12 capillary loops/mm at the nail fold but when that drops down to three, four or five then obviously some have been destroyed and the greater the loss of capillary loops, the worse the outcome.”

Patients with diffuse disease had significantly higher drop out scores than patients with limited or overlap disease.

The study also found patients with autoantibodies to RNA polymerase lll had higher levels of capillary damage than patients with CENP, Sci70 and RNP autoantibodies.

Further analysis suggested that nailfold capillary damage helped mediate the effects of the different autoantibodies.

“We thinks it’s a sequence; that’s the hypothesis. Autoantibodies are the first manifestation then capillaries start dropping out – so if you lose a lot of capillaries early on, you probably have a more aggressive type of scleroderma.”

Professor Roberts-Thomson said they had previously demonstrated a similar association between greater capillary drop out and the likelihood of pulmonary arterial hypertension as a complication of scleroderma.

“Other people have shown it is also more likely that patients with greater capillary drop out get more digital ulcers and greater skin fibrosis.”

“What we’re saying is that sequential nail fold capillaroscopy where you quantitate the number of capillaries that are being lost, may well have useful prognostic inferences.”

He added scleroderma was ‘a miserable disease’ with high morbidity, early mortality and until recently, no proven treatment to change its natural course.

However myeloablative autologous hematopoietic stem-cell transplantation has recently been shown to deliver long-term benefit in patients with severe scleroderma.