Forum for Nordic Dermato-Venereology Nr 3, 2018 | Page 13

Nicolas Kluger – Livedo reticularis and livedo racemosa Definition of “physiological” and “pathological” livedos Definition of whether the livedo is physiological and benign or related to a condition (and therefore pathological) is made following a meticulous examination of the livedo (Table I). Physical examination is carried out with the patient lying down and then standing up. The physician must first describe the pattern, by answering the following questions: • Are the lines of the livedo, thin and regular, or thick and irregular? • Does the livedo show closed unbroken circles (resembling a fishing net) or open broken circles (resembling lightning)? • On palpation, is the livedo infiltrated into any part? • Is there any necrotic lesion on any part of the livedo? • Are there any triggering factors? • Is the livedo acute, transient or permanent? • Is it worsened by cold exposure or standing? • What was the age of onset of the livedo (early or late)? • Where is the livedo localized on the body (lower limbs, face, trunk, buttocks, upper limbs)? • Is the distribution generalized or patchy? • Are there any other cutaneous symptoms that could arise suspicion for a pathological livedo: purpura, nodules, atrophic lesions, blue toe, etc. Cutis marmorata, livedo reticularis or livedo race- mosa? One of the main issues regarding the diagnosis of “livedo” is the confusing terminology used in the medical literature, which can easily mislead the physician (1–3, 7). “Cutis marmorata” is an English medical term referring to physiological livedo reticularis. Nowadays, it should be avoid- ed for such purpose. However, the term “cutis marmorata” is still used in the newborn condition, cutis marmorata telangi- ectatica congenita (or Van Lohuizen syndrome). Briefly, this is a peculiar necrotic and atrophic livedo of newborns, that can be localized (on the limb, head, etc.) or diffuse. Its evolution is variable, ranging from regression to stability or scarring. Its diagnosis is clinical and it may be associated with various other genetic conditions (macrocephalia, homocystenuria, trisomy 21, Cornelia de Lange syndrome, etc.) (8). Fig. 2. Examples of physiological livedo reticularis appearing during the consultation. “Livedo reticularis” describes a livedo that has thin and regu- lar lines, closed, unbroken circles, in other words the typical “fishing net pattern” (Fig. 2). Livedo reticularis may be either physiological or pathological. “Livedo racemosa”, a term first used first by Ehrmann in 1907 (9), describes a livedo with irregular lines, open, broken cir- cles, resembling “forked lightning” (Fig. 3). Livedo racemosa is always pathological and the underlying disorder must be actively managed. Lastly, the term “retiform purpura” describes a peculiar pur- pura with stellated borders (Fig. 4). This is related to a vessel occlusion and subsequent haemorrhage secondary to a period of ischaemia. The causes of retiform purpura overlap the causes of an infiltrated and necrotic livedo racemosa (10). Full clinical and physical examination It is mandatory to avoid unnecessary exploration and to de- fine the livedo. Personal and familial history should be fully Table II. Signs of a “pathological” livedo • • • • • • • Thick, irregular lines Open circles Painful livedo Infiltrated livedo Necrotic livedo Localization on the trunk, buttocks and face Other cutaneous symptoms: purpura, papules, nodules, blue toe, etc. Forum for Nord Derm Ven 2018, Vol. 23, No. 3 Fig. 3. Non-infiltrated livedo racemosa of the elbow. E ducational R eview 75