Serpent-Inspired Patterns in Dermatology: A Morphological Odyssey

Introduction The term serpiginous derives from the Latin serpere, meaning “to creep,” and aptly describes the winding, snake-like pattern observed in various dermatological conditions. This unique morphology spans a wide spectrum of etiologies, including infectious, inflammatory, vascular, and neoplastic processes. The recognition of serpiginous patterns in skin lesions can serve as a crucial diagnostic clue, often pointing toward specific diseases. This article explores the notable dermatological entities that exhibit serpiginous configurations, highlighting their clinical features, pathogenesis, and diagnostic implications, which are summarized in Table 1.Table 1: Summary of serpent-inspired patterns in dermatologyClinical serpiginous patterns Annular elastolytic giant cell granuloma It is a rare granulomatous disorder with uncertain pathogenesis. It is characterized by distinct erythematous annular plaques in a polycyclic or serpiginous pattern [Figure 1], typically appearing in regions exposed to sunlight.[1] Figure 1: A serpentine or polycyclic configuration of erythematous annular plaques on the left arm and forearm of a 40-year-old female, characteristic of annular elastolytic giant cell granulomaAngioma serpiginosum It is a rare vascular malformation with unknown etiology. It is characterized by the development of vascular reddish papules and macules in childhood. The lesions often have a linear serpiginous pattern and are unilateral. Extracutaneous manifestations are rare.[2] Circinate balanitis Circinate balanitis presents as tiny vesicles or pustules on the glans penis that erupts to form painless superficial erosions and that can combine to form a serpiginous pattern.[3] Cutaneous larva currens It is a pathognomonic and cutaneous sign of Strongyloidiasis stercoralis. Clinically, it appears as a linear or serpiginous, erythematous, papular, itchy, recurrent subcutaneous trail that is a few centimeters long and migrates quickly at the rate of 5 cm/h–15 cm/h. The most common sites of occurrence are the abdomen, perineal region, or buttocks.[4] Cutaneous larva migrans Cutaneous larva migrans (CLM), also known as creeping eruption, sandworm, plumbers itch, duck hunters itch, and epidermatitis linearis migrans, is a dermatitis caused by the invasion and migration of larvae of parasites in the skin. The first lesion in CLM is a papular, itchy, erythematous lesion. In a short time, a slightly elevated, pink, or flesh-colored swelling that is 2 mm to 3 mm thick generates tracks that are straight, serpentine (serpiginous), or bizarre shaped. [Figure 2][5] Figure 2: A serpiginous, slightly elevated, erythematous track on the left knee of a 30-year-old male, characteristic of cutaneous larva migransCutaneous pili migrans Yaffee first described the unusual disease in 1957. Cutaneous pili migrans (CPM) are hair fragments implanted in the epidermis and dermis layers of skin. It presents a blackish, linear eruption that resembles a serpiginous eruption. The most commonly involved sites are the toe, sole, ankle, breast, cheek, neck, and abdomen.[6] Cutaneous sparganosis Cutaneous sparganosis is a rare parasitic infection caused by the plerocercoid larva (sparganum) of Spirometra species. It typically results from consuming raw or undercooked amphibians, reptiles, infected water, or using contaminated flesh for wound healing. Clinically, cutaneous sparganosis can mimic CLM, presenting as creeping, serpiginous, or migratory linear lesions due to the larval migration in subcutaneous tissues.[7] Elastosis perforans serpiginosa Elastosis perforans serpiginosa is one of the four traditional primary perforating illnesses, along with reactive perforating collagenosis, perforating folliculitis, and Kyrle disease, which were initially identified by Lutz in 1953. It is characterized by isolated dermal elastosis, trans-epidermal removal of aberrant elastic fibers, and hyperkeratotic papules.[8] Epidermolysis bullosa (EB) pruriginosa (serpiginous pattern) One uncommon form of dystrophic EB is called epidermolysis bullosa pruriginosa. It can appear late in life and is typified by severe itching, which gives it a phenotype like acquired inflammatory dermatoses. It usually presents on the shin, appearing as lichenified plaque with marked scarring.[9] Rarely it presents in a serpiginous pattern.[10] Erythema gyratum repens The dermatosis, erythema gyratum repens, appears clinically as a serpiginous, erythematous condition with a fine scale behind the leading edge. Often, this appearance is termed a wood-grained appearance.[11] Erythema marginatum in hereditary angioedema First reported by Osler in 1888, erythema marginatum is a nonpitting, nonpruritic, serpiginous rash that may appear hours to days before the start of a C1-INH hereditary angioedema event or even develop separately from the angioedema.[12] Giant serpiginous plantar syphilid It is an unusual presentation seen in the case of secondary syphilis. It usually presents in the palmoplantar region as painful erosion.[13] Head of Medusa sign It is a clinical finding seen in portal hypertension. The abdominal varicose veins radiating from the navel to the periphery through the abdominal wall are known as the head of Medusa sign.[14] Medusa head-like granules in squamous cell carcinoma It is an electron microscopic finding seen in squamous cell carcinoma. Medusa head-like granules are seen in the cytoplasm of the clear squamoid cells adjacent to the keratinized cells.[15] Scabies Skin burrows and scabietic nodules are the pathognomonic features of scabies. The burrow represents the female mite’s living tunnel; a narrow, serpiginous grey line that measures 1 mm to 10 mm and is located on the hands and feet, namely on the finger web gaps, thenar, and hypothenar eminences.[16] Serpiginous hypopigmentation due to intraarticular steroid injection It is one of the cutaneous adverse effects associated with the use of intra-articular corticosteroid injection. These side effects occur when steroid is used in high potency, for prolonged duration, or in high-risk areas.[17] Mycosis fungoides: In the plaque stage of mycosis fungoides, plaques may group and cover a large portion of the body, creating an arcuate, serpiginous, or annular border.[18] Ichthyosis Linearis Circumflexa It is a clinical finding seen in patients with Netherton syndrome. It presents as erythematous, serpiginous lesions on the trunk and/or limbs with a double-edged scale at the margin of the lesions.[19] Subcorneal pustular dermatosis Subcorneal pustular dermatosis (SCPD) is also known as Sneddon-Wilkinson syndrome. Unlike pustular psoriasis, isolated or confluent pustules in SCPD have a distinct topography and tend to create annular, circinate, or serpiginous patterns. The commonly affected sites include axillae, groin, abdomen, sub-mammary regions, and flexor aspects of the limbs.[20] Erythema marginatum It is one of the cutaneous manifestations of acute rheumatic fever. The rash of erythema marginatum manifests as a circular, erythematous, nonpruritic rash with serpiginous margins. The rash may spontaneously fade and reappear on the trunk and limbs.[21] Serpentine supravenous hyperpigmentation Hrushesky coined the term “supravenous serpentine hyperpigmentation” to refer to the enhanced skin pigmentation directly overlying the venous network [Figure 3]. It is a rare side effect of administering some anti-cancer medications, including nitrogen mustard, cyclophosphamide, actinomycin, doxorubicin, vinca alkaloids, taxanes, and bortezomib. Although the precise process of pigment induction is uncertain, it has been hypothesized that these cytotoxic medications result in the vascular endothelium losing its integrity.[22] Figure 3: Serpentine hyperpigmentation along the venous network on the left forearm, characteristic of supravenous hyperpigmentationWaldenstrom macroglobulinemia with serpiginous purpura An uncommon form of Waldenstrom macroglobulinemia that occurs when IgM is deposited in the dermis is called cutaneous macroglobulinosis. Clinically, it manifests as purpura in a serpiginous pattern.[23] Dermoscopic serpiginous patterns Medusa head in woolly hair syndrome The term “woolly hair” describes an aberrant kind of fine, tightly curled hair that frequently shows reduced pigmentation in cases of woolly hair syndrome. Three types of woolly hair include autosomal dominant hereditary woolly hair, autosomal recessive familial woolly hair, and woolly hair nevus. Syndromic autosomal recessive variants are linked to cardiovascular problems and palmoplantar hyperkeratosis. Wolly hair can be easily appreciated through trichoscopy.[24] Serpentine blood vessels It is a dermoscopic finding seen in cutaneous malignancies such as melanoma and basal cell carcinoma, where the blood vessels appear in a serpentine, linear, or irregular pattern.[25] Serpiginous brown dots in verrucous epidermal nevus It is a dermoscopic finding seen in the case of verrucous epidermal nevus. These serpiginous brown dots represent the presence of pigment at the dermo-epidermal junction. These findings aid in the diagnosis of verrucous epidermal nevus.[26] Serpentine ulceration due to jellyfish sting It is the dermoscopic finding seen in Pelagia noctiluca (jellyfish) stings. The contact with the jellyfish’s tentacles causes superficial linear ulceration, which appears as a winding road known as “serpentine ulceration.” They present as linear purpura in the center of the ulcer and brown spots along the ulcer’s margins, which are marked by scales.[27] Serpiginous vessels It is a dermoscopic finding seen in the case of clear cell acanthoma, in which the globular vascular structures appear in a serpiginous pattern.[28] Conclusion Serpents have always caught the imagination of humans so much that they are worshipped worldwide. The serpentine pattern is easily remembered and interpreted. The serpiginous pattern is a unifying morphological theme across a diverse array of dermatological conditions. By refining our understanding of these serpiginous entities, dermatologists can enhance their clinical acumen and optimize patient outcomes. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. Use of artificial intelligence (AI) The preparation of this manuscript was carried out entirely by the author without the use of artificial intelligence technologies.