Forum for Nordic Dermato-Venereology Nr 3, 2018 | Page 14

Nicolas Kluger – Livedo reticularis and livedo racemosa
use. The main causes include: low circulatory flow, in case of
cardiogenic, septic shock or hypovolaemia especially. Neuro-
logical diseases in case of immobility stasis, reflex sympathetic
dysfunction or dysautonomia may be responsible for such
livedo. A few drugs are known to cause livedo reticularis, such
as amantadine, a treatment for Parkinson’s disease, multiple
sclerosis or hepatitis C, and interferon or noradrenaline. Pheo­
chromocytoma is a rare cause of livedo reticularis. However,
this list of causes is not exhaustive.
Livedo racemosa
Fig. 4. Necrotic livedo/purpura retiform (notice the “stellate” borders)
due to skin thrombosis related to cryoglobulin type I and multiple
myeloma (11).
assessed, including systematic cardiovascular history (arterial
hypertension, valvulopathy, atherosclerosis, thrombophlebi-
tis, loss of consciousness, etc.), central nervous system diseases
(migraines, stroke, transient ischemic attacks, seizures), ocular
manifestations (diplopia, amaurosis, etc.), kidney (chronic
renal failure, urolithiasis, etc.), pregnancies (spontaneous
miscarriages, hypertension, eclampsia, prematurity). A com-
plete physical examination must be carried out following
the patient’s history. Subsequently, the physician will be able
to diagnose whether the patient has a livedo reticularis, and
whether it is physiological or pathological, or if it is a livedo
racemosa.
Physiological livedo reticularis
Physiological livedo reticularis is a common condition due to
a vasospastic phenomenon affecting mainly neonates, infants
and young people. It displays thin, regular lines, closed circles,
and a fishing net pattern. It is aggravated by cold and improved
by warming, affecting mainly the extremities and sometimes
the trunk. It appears typically during the examination of a
patient in underwear, if the room is a little cold. Women
under 40 years of age may display other symptoms, such as
acrocyanosis, chilblains and anorexia nervosa. Physiological
livedo reticularis may be more extensive and not improved
by warming. It does not require any additional exploration.
There is no effective treatment, expect sun-tanning, which
may mask the livedo (1).
There are 3 pathological mechanisms that may be responsible
for livedo racemosa: inflammation of blood vessels (vasculitis),
thrombosis of blood vessels (Fig. 5) (11) and embolization
process within the blood vessels (12).
A correct diagnosis of livedo racemosa can only be made at that
stage by microscopic examination of a full-thickness biopsy
up to the hypodermis. The most infiltrated or necrotic lesion
should be chosen preferably for the biopsy. Punch skin biop-
sies should be avoided, as the sample could be too superficial
and therefore miss the pathogenic process diagnosis. In the
absence of any infiltration or necrosis within the livedo, the
biopsy should be performed in the centre of the net/hexagon
(where the central capillary arteriole is located) and in some
cases also on the livedo itself (where the capillary venules are
located). In some cases, multiple biopsies may be required to
make a correct diagnosis. In addition, biopsies of other skin
lesions may be performed.
According to the histological results, a wide number of causes
may be responsible. The personal history of the patient and the
clinical examination help to orientate the diagnosis. The list
Pathological livedo reticularis
Vasospam is responsible for livedo reticularis. The diagnosis
of pathological livedo reticularis is rapid and easy due to the
clinical history. A skin biopsy is not contributive and is of no
76
E ducational R eview
Fig. 5. Rapidly lethal generalized necrotizing thrombotic livedo racemosa
of unknown origin in a middle-aged woman.
Forum for Nord Derm Ven 2018, Vol. 23, No. 3