Cumhuriyet Medical Journal

Abstract

To the Editor

The
acute blue finger is an uncommon disorder. It is an isolated problem and may
have many causes¹. The causes of isolated acute blue discoloration
of a finger may be acute ischemia or vasospasm and underlying systemic
illnesses. However, in some cases, there is no association with any dangerous
causes or systemic diseases². The most common etiological causes are
Raynaud’s disease or syndrome, infective endocarditis, peripheral vascular
disease, thoracic outlet obstruction, subclavian artery stenosis,
cryoglobulinemia,  frostbite, trauma,
vibration- induced injury and certain poisons^1,3.

A
39-year-old female patient admitted with bluish discoloration of the distal phalange
in the right thumb. She has no history of trauma, cold exposition, weight loss
and other constitutional symptoms. She experienced two episodes of acute finger
discoloration over one month. The first episode involved a spontaneous and
sting purple “lump” at the base of the of the distal phalanx of her right
thumb. The lesion resolved within several days spontaneously. A second episode
with the same clinical symptoms involving the same finger was three weeks later
after the first episode. Symptoms resolved within one day spontaneously.

Personal
medical history was normal. She was physically normal in weight. She has no
fever or other systemic symptoms. The blood pressure of her upper extremity was
100/60 mm Hg, symmetrically. Pulse of upper and lower extremities was normal
and regular. There was no murmurs or bruits. She had no neurological sign or
symptoms. There were no differences in the arterial pressure between the right
and left upper limbs. Allen’s test measuring arterial competency and Adson maneuver
for thoracic outlet syndrome was normal. There were no embolic phenomena of the
upper and lower extremities.

Local
examination of right hand revealed bluish discoloration of the distal phalanx
of her right thumb with sparing of tips (Figure 1). There was no swelling,
tenderness, temperature variation, deformities or signs of trauma.  Cold and warm exposure did not show any
changes in color. Complete blood count including coagulation tests, renal and
liver functions was normal. Electrocardiogram, echocardiography and chest X-ray
have no abnormalities.  Erythrocyte
sedimentation rate was 14 mm/h and C-reactive protein 1.5 mg/L. Antinuclear
antibody was positive at 1:40 and negative at 1:160. Rheumatoid factor, anti-cyclic
citrullinated protein, and anti-SCL 70 were negative. Doppler study of her
right upper limb vessels and ankle brachial index were also normal. She was
ultimately diagnosed with an acute benign blue finger.  She was also symptom-free for the past one
month.

The acute idiopathic blue finger is a benign and
rare condition. It is characterized by an acute bluish discoloration of
fingers which may be accompanied by pain⁴. The acute blue finger appears to
occur in all age groups, predominately affecting the female, middle-aged
population¹. Spontaneous acute blue finger syndrome is an entity
different from ischemia or vasospasm. The mechanism of subcutaneous bruising
has been offered. Lesions usually disappear without the stages of ecchymosis
resorption. The patients presenting with acute blue fingers should be rapidly
clinically evaluated. The absence of any thromboembolic disorders or systemic
diseases indicates a benign clinical course². In a prospective
follow-up of 22 patients who had presented with sudden onset blue discoloration
of a finger with normal radial and ulnar pulses, it was concluded that acute
blue finger is generally a benign condition not suggestive of arterial
embolization and with no threat from digit loss¹.

Acute
blue finger cases rarely refer to dermatology outpatient clinics. We want to
emphasize that acute blue finger is usually benign disorder. However, it should
be necessarily ruled out its possible causes.