Dermatology Online Journal

Dermatology misnomers
Neda Nosrati MD, Mandy S Harting MD, Deborah J Yang MD, Yang Angela Shen MD, Jennifer L Maender MD, Reena P Jogi MD, Michael L Sonabend MD, Sylvia Hsu MD
Dermatology Online Journal 14 (1): 22

---

In dermatology there are many disease names and terms that may be misleading to physicians outside the specialty. Herein, we have discussed a few examples of diseases that cannot be interpreted literally. Several relevant misnomers such as impetigo herpetiformis, mycosis fungoides, pyogenic granuloma, herpes gestationis, and lupus anticoagulant were omitted from this list because they were previously reported by Barankin and Freiman [1].

Pyoderma gangrenosum

Pyoderma gangrenosum (PG) is an idiopathic chronic, neutrophilic inflammatory and ulcerative skin disease. Clinically the skin lesions can present as painful, erythematous to violaceous papules, sterile pustules, vesicles, or fluctuant nodules that may ulcerate demonstrating sharply circumscribed, undermined borders with a necrotic bases. On histology PG demonstrates edema and a predominantly neutrophilic infiltrate. The presence of a lymphocytic vasculitis, follicular-based pustule, or necrosis and hemorrhage may be observed. Although the pathogenesis is not well understood, it is of an autoimmune etiology and not an infectious one [2]. Therefore, pyoderma is not an appropriate term to describe this lesion.

Lupus pernio

Lupus pernio is a rare but characteristic skin manifestation of sarcoidosis. The lesions are often deforming and appear as chronic, hyperpigmented or violaceous nodules or plaques of the nose, cheeks, ears, and central face. Histology shows sarcoidal granulomas [3]. Pernio, or chilblains, is a localized inflammatory lesion of the skin resulting from an abnormal response to cold. Pernio most commonly occurs in young women but may occur in older individuals or in children. Single or multiple erythematous-to-purplish, edematous plaques appear secondary to cold exposure and are accompanied by intense pain, itching, or burning [4]. The term lupus pernio is a misnomer because the condition is not associated with lupus and has no association with pernio.

Lupus miliaris disseminatus faciei (LMDF)

Lupus miliaris disseminatus faciei is a granulomatous disorder characterized by discrete, red-brown, dome-shaped papules located on the medial and lateral aspects of the face, chin, and neck. Histopathology demonstrates caseating and noncaseating epithelioid cell granulomas [5]. Although it was originally suspected to be a variant of lupus vulgaris or a tuberculid, there has been no evidence to support these associations. Therefore, the term lupus is incorrect in describing this lesion. Currently, LMDF is considered a papular form of rosacea, because the granulomas seen in the lesions appear to be associated with pilosebaceous units [6].

Myxoid cyst

Digital myxoid cysts occur over the distal phalanx of the finger or rarely the toe, appearing as solitary, shiny, tense, opalescent papules. There are currently two variations of these cysts. The first arises in the proximal nailfold and is a form of focal mucinosis. The other arises in proximity to the distal interphalangeal joint as a result of an extension of the joint lining due to osteoarthritis and thus resembles a ganglion cyst. Many of the former type of cyst do not exhibit a lining histologically and therefore may be more appropriately termed pseudocysts [7].

Transient acantholytic dermatosis (TAD)

Transient acantholytic dermatosis was first described by Ralph Grover in 1970 and is therefore also known as Grover disease. It is a pruritic, papular or papulovesicular eruption most commonly occurring on the trunk characterized by focal acantholysis with or without dyskeratosis on histology [8]. TAD is self-limited disorder usually lasting less than 3 months [9], but it is not always transient as a study by Davis et al of 72 patients with TAD demonstrates. Their results show that only 43 percent of patients followed at 38 months had resolution of disease [10]. Therefore, TAD is a misnomer because it is not always transient.

Granuloma faciale

Granuloma faciale is a chronic benign skin disease characterized by one or more brown-red plaques, papules, or nodules usually on the face, although extrafacial lesions can occur. The most frequent histopathologic features of granuloma faciale are the presence of a grenz zone, mixed inflammatory infiltrate including neutrophils and lymphocytes, and telangiectasias; however, granulomas are never seen [11]. Therefore, granuloma faciale is a misnomer as granulomas are not demonstrated on histology in these lesions. Additionally, it is a misnomer since lesions can occur in locations other than the face.

Kaposi sarcoma (KS)

Kaposi sarcoma is a multisystem angioproliferative disorder characterized by proliferation of spindle-shaped cells, neo-angiogenesis, inflammation, and edema. There are four clinical variants of KS including classic, African, transplant-related, and AIDS-related, all of which are now known to be associated with the gamma herpes virus, HHV 8 [12]. Cells infected with HHV 8 produce cytokines, chemokines, and growth factors, which cause proliferation of endothelial and spindle cells. There is controversy as to whether these proliferative cells truly represent a malignant neoplasia versus an inflammatory hyperplasia [13]. Therefore, the term sarcoma used in the description of this condition may not be warranted.

Bullous congenital ichthyosiform erythroderma (BCIE)

Bullous congenital ichthyosiform erythroderma is a rare autosomal dominant disorder of keratinization caused by a genetic defect of the epidermal keratins, K1 and K10, which leads to impairment in the tonofilament network of differentiating epidermal cells. The disorder presents at birth with generalized erythema, blistering, and erosions, followed in time by hyperkeratosis [14]. Erythroderma or exfoliative dermatitis describes generalized redness of the skin, usually more than 90 percent of the body surface area, with variable degrees of scaling caused by underlying dermatoses, drug reactions, malignancies, systemic diseases, infections and idiopathic disorders [15]. Therefore, bullous congenital ichthyosiform erythroderma is not a true form of erythroderma, although it does resemble erythroderma clinically.

Capillaritis

Capillaritis is a pigmented purpuric dermatosis which is a group of chronic, purpuric, pruritic eruptions that usually occur on the lower extremities. Capillaritis is usually associated with chronic venous hypertension. This group of dermatoses shares characteristics, histologically demonstrating extravasation of red cells, variable hemosiderin deposition, and perivascular lymphocytic infiltrates without leucocytoclastic vasculitis [16]. Capillaritis is a misnomer as there is no vasculitis involved.

Tinea amiantacea

Tinea amiantacea is a cutaneous disease that affects the scalp and is characterized by thick, asbestos-like scaling that results in hair follicles becoming bound down. Alopecia is often associated with this disorder and may be temporary or scarring [17]. The etiology is unknown; however, previous reports suggest it may be a manifestation of psoriasis or seborrheic dermatitis [18]. It is a misnomer to term this disease tinea because it is typically not associated with a dermatophyte infection.

Fibroepithelioma of Pinkus

This is a cutaneous tumor which clinically appears as a solitary, skin-colored or slightly brown-gray, well-demarcated plaque. It is most often found on the trunk, especially in the lumbosacral area, of 40-60-year-old patients and is equally distributed in men and women. Although normally it is indolent and non-aggressive, it can rarely invade underlying tissue [19]. It is generally regarded as a rare variant of basal cell carcinoma (BCC), which is supported by a recent paper by Ackerman et al. listing several criteria for considering fibroepithelioma of Pinkus a variant of BCC [20]. Therefore, fibroepithelioma is not an accurate term for this disease.

Granuloma fissuratum

Granuloma fissuratum is a reactive skin process resulting from chronic trauma commonly from ill-fitting eyeglasses. Therefore, it usually presents on the nose and ears, but it has been reported on the mouth and vulva as well [21]. It is important to differentiate granuloma fissuratum from basal cell carcinoma as the two can be very similar clinically. On histopathology, granuloma fissuratum displays epidermal hyperplasia with fibrosis and patchy chronic inflammatory cell infiltrate, but no granulomas are seen [22]. Therefore granuloma fissuratum is an inaccurate description of this lesion.

Nevus depigmentosus

Nevus depigmentosus is a rare, nonprogressive congenital hypopigmented macule or patch that remains stable over time. It occurs sporadically and is likely caused by a defect in the development of fetal melanocytes. Included in the differential diagnosis are vitiligo and idiopathic guttate hypomelanosis. Histopathology is similar to that of normal skin except for a decrease in density of melanosomes but normal or only mildly decreased in numbers of melanocytes [23]. The term nevus depigmentosus is a misnomer because the lesions are hypopigmented, not devoid of pigment as the name would imply.

Palisaded encapsulated neuroma

Palisaded encapsulated neuroma is characterized by a solitary, asymptomatic, skin-colored papule located usually on the face of middle-aged individuals. It is thought to result from neural regeneration after trauma. Palisaded encapsulated neuroma is often misdiagnosed as basal cell carcinoma or intradermal nevus. Histologically, there are localized dermal lobules composed of interlacing Schwann cells with variable numbers of fine axons and myelin sheaths present. Palisading nuclei are not a prominent feature [24]; therefore, the term palisaded does not correctly describe this lesion. Additionally, although it is well-circumscribed, it is not truly encapsulated.

Seborrheic keratosis

Seborrheic keratoses are the most common benign tumor encountered in older individuals, present in 80-100 percent of people over age 50. The exact etiology is unknown, but cumulative exposure to sunlight is likely involved. Clinically, they are brown verrucous plaques with a stuck-on appearance. Although they can be found anywhere on the body excluding the palms, soles, and mucosal membranes, they are most often located on the trunk, dorsal hands, and face. Therefore, they are not limited to a seborrheic distribution. Seborrheic keratoses result from a proliferation of keratinocytes and are not related to sebaceous glands [25]. Therefore, these keratoses should not be termed seborrheic.

Infantile myofibromatosis

Infantile myofibromatosis is a benign neoplasm of infancy, usually present at birth. Clinically it presents as a solitary nodule 70-80 percent of the time, most commonly on the head, neck and trunk. The multicentric forms may have visceral involvement with an increase in mortality. Histology shows an unencapsulated, well-circumscribed lobule of peripheral spindle cells, resembling smooth muscle. A central area with blood vessels surrounded by small rounded cells is also often seen, giving infantile myofibromatosis its biphasic appearance. Treatment has traditionally consisted of radical excision, but recent evidence shows that solitary lesions may regress. Therefore, a watch and wait approach may be warranted in certain cases [26]. The name infantile myofibromatosis is a misnomer because the most common form of this disorder is solitary, not multicentric as the name implies.

Within this brief report, we have only begun to describe the vast number of misnomers in dermatology. It is important as dermatologists that we understand our own misleading diagnostic terms and attempt to educate other physicians.

References

1. Barankin B, Freiman A. Misnomers in Dermatology. J Cutan Med Surg. 2005 Dec;9(6):284-288. PubMed

2. Hasselmann DO, Bens G, Tilgen W, Reichrath J. Pyoderma gangrenosum: Clinical presentation and outcome in 18 cases and review of the literature. J Dtsch Dermatol Ges. 2007 Jul;5(7):560-564. PubMed

3. Khatri KA, Chotzen VA, Burrall BA. Lupus Pernio: Successful treatment with a potent topical corticosteroid. Arch Dermatol. 1995;131(5):617-618. PubMed

4. Simon TD, Soep JB, Hollister JR. Pernio in pediatrics. Pediatrics. 2005 Sep;116(3):e472-5. PubMed

5. van de Scheur MR, van der Waal RF, Starink TM. Lupus miliaris disseminatus faciei: a distinctive rosacea-like syndrome and not a granulomatous form of rosacea. Dermatol. 2003;206:120-123. PubMed

6. Watabe A, Okuyama R, Tagami H, Aiba S. Lupus miliaris disseminatus faciei associated with epidermal cysts. Dermatol. 2007;214:272-273. PubMed

7. Butler DF, Davis G, Greene JF. Multiple mucinous (myxoid) cysts of a single finger. J Am Acad Dermatol. 2005 Nov;53(5):914-916. PubMed

8. Scheinfeld N, Mones J. Seasonal variation of transient acantholytic dyskeratosis (Grover's disease). J Am Acad Dermatol. 2006 Aug;55(2):263-268. PubMed

9. Chalet M, Grover R, Ackerman AB. Transient acantholytic dermatosis: a reevaluation. Arch Dermatol. 1977 Apr;113:431-435. PubMed

10. Davis MD, Dinneen AM, Landa N, Gibson LE. Grover's disease: clinicopathologic review of 72 cases. Mayo Clin Proc. 1999 Mar;74(3):229-34. PubMed

11. Ortonne N, Wechsler J, Bagot M, Grosshans E, Cribier B. Granuloma faciale: A clinicopathologic study of 66 patients. J Am Acad Dermatol. 2005 Dec;53(6):1002-1009. PubMed

12. Pantanowitz L, Dezube BJ. Advances in the pathobiology and treatment of Kaposi sarcoma. Curr Opin Oncol. 2004 Sep;16(5):443-449. PubMed

13. Schwartz RA. Kaposi's sarcoma: Advances and perspectives. J Am Acad Dermatol. 1996 May;34(5):804-814. PubMed

14. Muller FB, Huber M, Kinaciyan T, Hausser I, Schaffrath C, Krieg T, Hohl D, Korge BP, Arin MJ. A human keratin 10 knockout causes recessive epidermolytic hyperkeratosis. Hum Mol Genet. 2006 Apr;15(7):1133-41. PubMed

15. Akhyani, M, Ghodsi Z, Toosi S, Dabbaghian H. Erythroderma: a clinical study of 97 cases. BMC Dermatol. 2005 May;5:5. PubMed

16. Yung A, Goulden V. Pigmented purpuric dermatosis (capillaritis) induced by bezafibrate. J Am Acad Dermatol. 2005 Jul;53(1):168-9. PubMed

17. Moon CM, Schissel DJ. Pityriasis amiantacea. Cutis. 1999 Mar;63(3):169-70. PubMed

18. Abdel-Hamid IA, Agha SA, Moustafa YM, El-Labban AM. Pityriasis amiantacea: a clinical and etiopathologic study of 85 patients. Int J Dermatol. 2003 Apr;42(4):260-4. PubMed

19. Zalaudek I, Ferrara G, Broganelli P, Moscarella E, Mordente I, Giacomel J, Argenziano G. Dermoscopy patterns of fibroepithelioma of pinkus. Arch Dermatol. 2006 Oct;142(10):1318-1322. PubMed

20. Ackerman A, Gottlieb G. Fibroepithelial tumor of Pinkus is a trichoblastic (basal-cell) carcinoma. Am J Dermatopathol. 2005 Apr;27:155-59. PubMed

21. Kennedy CM, Dewdney S, Galask RP. Vulvar Granuloma Fissuratum: A Description of Fissuring of the Posterior Fourchette and the Repair. Obstet Gynecol. 2005 May;105:1018-1023. PubMed

22. Farrell WJ, Wilson JW. Granuloma fissuratum of the nose. Arch Dermatol. 1968 Jan;97:34–7. PubMed

23. Kim SK, Kang HY, Kim YC. Clinical and Histopathologic characteristics of nevus depigmentosus. J Am Acad Dermatol. 2006 Sep;55(3):423-8. PubMed

24. Dover JS, From L, Lewis A. Palisaded Encapsulated Neuromas. A Clinicopathologic study. Arch Dermatol. 1989 Mar;125(3):386-9. PubMed

25. Hafner C, Hartmann A, Real FX, Hofstaedter F, Landthaler M, Vogt T. Spectrum of FGFR3 Mutations in Multiple Intraindividual Seborrheic Keratoses. J Invest Dermatol. 2007 Aug;127(8):1883-85. PubMed

26. Weinberger CH, Dinulos JG, Perry AE. An enlarging tender nodule on the finger of a 4-year-old boy: an unusual presentation of infantile myofibromatosis. J Am Acad Dermatol. 2007 Aug;57(2):S30-2. PubMed

© 2008 Dermatology Online Journal