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Susan Allen, PgD(Comm), MRPharmS is a freelance
pharmaceutical writer and copy writer from Market Harborough, Leicestershire
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CORRECTION
(22/29 December 2007)
The dose (unlicensed) for iloprost intravenous
infusion (p650) should have read 2ng/kg/min and not 2ng/kg.
Schering
Health advises that the dose is adjusted according to individual
tolerability within the range of 0.5 to 2.0ng/kg/min over six hours
daily.
Treatment periods of three to five days are often
sufficient in Raynaud’s phenomenon to achieve improvement over several
weeks. |
Vasospasm cuts off the blood supply in the affected fingers, resulting
in whitening and pain |
RESOURCES
Raynaud's & Scleroderma |
SUMMARY
Raynaud’s phenomenon was first described in 1862 by Maurice Raynaud.
It is characterised by episodic spasming of the small blood vessels of
the extremities. The fingers are most commonly affected, but vasospasm
can also occur in the toes, nose, ears and, occasionally, the tongue
and lips.
The vasospasm cuts off the blood supply in the affected fingers, resulting
in whitening and pain. This is sometimes followed by cyanosis (the affected
fingers turn blue) due to pooling of deoxygenated blood.
An episode ends
with vasodilation and reperfusion and the finger(s) turns red. This white-blue-red
colour change is characteristic of the reversible local ischaemia but
is not observed in all patients.
The ischaemic pain during an attack can be considerable and has been
compared to plunging your hands into a bucket of icy water and holding
them there. As blood flow returns, in the final stage, there is often
tingling, throbbing, numbness and further pain. During an attack, hand
function is limited.
The vasospasm is thought to be an exaggerated response
to cold or some other form of stress. Attacks are usually mild and last
for a few minutes, but some people experience multiple and prolonged
episodes, lasting hours.
When Raynaud’s symptoms first present, one or two fingers may be
affected but, with time, all fingers tend to become involved. Episodes
tend to be symmetrical, affecting each hand equally. Complications of
the phenomenon include ulceration, scarring and pitting, and gangrene,
but these are rare.
In over 90 per cent of cases there is no identifiable cause for the
condition and this is termed primary Raynaud’s phenomenon (also
sometimes referred to as Raynaud’s disease).
If, however, the condition
is due to an underlying disease (see Panel 1, below, for examples), it
is described as secondary Raynaud’s phenomenon.
Panel 1: Causes of secondary
Raynaud’s phenomenon
• Connective tissue disease (eg, scleroderma,
Sjögren’s
syndrome, systemic lupus erythematosus, systemic vasculitis)
• Autoimmune disease (eg, rheumatoid arthritis)
• Obstructive arterial disease (eg, atherosclerosis, thromboembolism)
• Neurological disorders (eg, carpal tunnel syndrome, multiple
sclerosis)
• Hyperviscosity disorders (eg, polycythaemia)
• Miscellaneous (eg, neoplasms, primary pulmonary hypertension,
hypothyroidism)
• Infections (eg, bacterial endocarditis, viral hepatitis) |
It has been estimated
that scleroderma accounts for 65 per cent of secondary Raynaud’s
phenomenon (see Panel 2, below).
Raynaud’s symptoms can also be
caused by exposure to vibration, known as “vibration white finger” (eg,
in occupations that involve using pneumatic drills or chainsaws), prolonged
cold (eg, in meat packers), or chemicals (eg, in the polyvinylchloride
industry).
Panel 2: Scleroderma
Scleroderma is rare, affecting 1 in 10,000 people
in the UK, but it can be a devastating condition. It is thought
to be an autoimmune
disease in which fibroblasts are stimulated to over produce collagen
(the major protein in connective tissue). As a result, the skin,
usually of the hands and feet, becomes thick, leathery, tight
and shiny. The blood vessels and internal organs can be similarly
affected.
Scleroderma is three times more common in women and most cases
are diagnosed between the ages of 25 and 55 years. Raynaud’s symptoms
are usually the first sign of the disease. Most (95 per cent) patients
with scleroderma have Raynaud’s phenomenon, but the chance
of someone with Raynaud’s developing scleroderma is less than
2 per cent.
There is no cure for scleroderma. Treatment is directed at symptom
control and decreasing immune system activity. |
Raynaud’s phenomenon has been linked to some autoimmune
diseases. Up to 5 per cent of patients with rheumatoid arthritis have
Raynaud’s
symptoms as do up to 30 per cent of people with systemic lupus erythematosus.
Drugs that can cause (or exacerbate) Raynaud’s phenomenon include
some angiotensin-converting enzyme inhibitors
(eg, enalapril and lisinopril) beta-blockers, some cytotoxics (eg, bleomycin,
cisplatin), bromocriptine, clonidine, ergotamines, lisuride, methysergide,
pergolide and sumatriptan.
Other drugs that have been linked with Raynaud’s
phenomenon include amphetamines, interferon-alpha, lithium and combined
oral contraceptives.
The overall incidence of Raynaud’s phenomenon is 3–20 per
cent of the adult population worldwide, with more women (over 90 per
cent) affected than men. In the UK, around 10 per cent of women experience
Raynaud’s phenomenon to some degree. Surveys of Scandinavian women
aged 18 to 60 years suggest that higher numbers are affected — up
to 22 per cent.
Typical age of onset is usually quoted as being in the teenage years
or early twenties. However, a recent Bandolier look at 10 studies including
639 patients found the average age of onset of primary Raynaud’s
phenomenon was 34 years.
Full article PDF 90K |
The
Pharmaceutical Journal