Drawing a Diagnosis
Submitted by gpig18 at June 3, 2012 - 12:56 am
Cold Damage
The cold can damage extremities in more ways that just frost bite. In Raynaud’s phenomenon, the cold triggers vasospasm in the fingers, obstructing flow distally. Classically, the fingers can go through 3 colour changes, representing the state of flow in the fingers. Firstly, white (or ‘pallor’), when the obstructed flow means blood is prevented from going to the fingers. Secondly, blue, due to a build up of deoxygenated haemoglobin: the cells in the fingers are using up the last of the available oxygen and creating carbon dioxide and other waste products. If this stage goes on for a long time, ischaemia and necrosis can occur. Unfortunately for this patient, this happened to her fingers on both hands. The skin had started desquamating (peeling off) in grey/black flakes on most finger tips. The final stage if the ‘blue’ stage has been more short term is the ‘red’ stage: reactive hyperaemia: as the blood flow returns to the fingers, the build up of waste products and carbon dioxide stimulates vasodilation: the result is a red, swollen digit which may feel ‘tingly’.
Raynaud’s disease is an idiopathic (no known cause) disease which often presents itself in young women. It has no known link to other connective tissue diseases. However, Raynaud’s syndrome, or ‘secondary raynaud’s’ presents as part of a wider connective tissue disease. It can often be a useful ‘warning shot’- it can occur 20 years before the onset of symptoms in CREST (or systemic sclerosis), and predates the onset of other symptoms in 70% scleroderma patients. Secondary raynaud’s or raynaud’s syndrome is more likely to have severe long term effects like necrosis, compared to the more transient ‘raynaud’s disease’.