eMedicine Specialties > Dermatology > Reactive & Inflammatory Dermatoses
Lichen Spinulosus
Updated: Oct 30, 2009
Introduction
Background
Lichen spinulosus is an uncommon dermatosis manifested by large patches of follicular papules topped by keratotic spines (see Media Files 1-2). In 1883, Crocker published a description of lichen spinulosus. Since then, few other similar reports were published until 1990, when Friedman presented data on 35 patients with lichen spinulosus.1 The etiology is unknown. Some minor progress has been made in therapy for lichen spinulosus.
Lichen spinulosus on the abdomen.
Close-up view.
Pathophysiology
The classic lesion of lichen spinulosus is a keratotic plug located within the dilated follicular orifice. Histologically, an inflammatory lymphohistiocytic infiltrate occurs around the follicle and in the dermis. Hyperkeratosis, parakeratosis, and acanthosis are visible in the follicle. Differentiating lichen spinulosus from keratosis pilaris by microscopy may not be possible.
In the past, lichen spinulosus was reported to be associated with the administration of arsphenamine, thallium, gold, and diphtheria toxin. More recently, authors have noted association with HIV disease2 and Crohn disease.3 These associations may reflect the interests of the authors. Kabashima et al reported lichen spinulosus in an alcoholic patient.4
Frequency
United States
Apparently, lichen spinulosus is not a common disorder. This conclusion is based on the paucity of published reports regarding lichen spinulosus.
International
Lichen spinulosus has been reported worldwide. In 1990, Friedman described 35 patients with lichen spinulosus. He and his coworkers in the Philippines examined 7435 people attending a dermatology clinic.1 The incidence of lichen spinulosus was approximately 5 cases per 1000 population with skin disorders. This prevalence exceeds reports from various American surveys on cutaneous diseases in children and adolescents.
Mortality/Morbidity
Lichen spinulosus affects only the skin and is not known to be associated with abnormalities of internal organ systems. Occasionally, a patient with lichen spinulosus reports pruritus. Otherwise, the disorder mostly is of cosmetic significance. Misdiagnosis can result in inappropriate treatment.
Race
Worldwide distribution suggests no predilection of lichen spinulosus in any ethnic group.
Sex
Case reports suggest an equal distribution of lichen spinulosus in males and females. Friedman's study in the Philippines included 14 males and 21 females.
Age
Reports indicate that lichen spinulosus is a disease that occurs during childhood to young adulthood. Peak incidence appears to occur during adolescence. Lichen spinulosus can persist for decades. In most patients, lichen spinulosus remits spontaneously within 1-2 years. Friedman calculated that in the Philippines, the average age at onset was 16.2 years ± 10.1 years.
Clinical
History
Lichen spinulosus tends to have a sudden onset and is not accompanied by other signs or symptoms. The keratotic papules group into large plaques that can spread rapidly to affect large areas of skin.
Physical
- Patches and plaques of follicular papules have a diameter that ranges from 2-5 cm.
- Patches are distributed symmetrically over the integument.
- Patches affect the neck, buttocks, abdomen, trochanters, knees, and extensor surfaces of the arms.
- Individual papules are flat to conical.
- Individual papules usually are small, approximately 1-3 mm in diameter.
- Papules have a pointed or hairlike horny spine that extends approximately 1 mm around the tip of the follicle.
- When a patch is rubbed gently with the fingers, it feels similar to a nutmeg grater.
Causes
The cause of lichen spinulosus is unknown. Infection has been postulated, but no data support this hypothesis. Other authors have suggested that lichen spinulosus is part of atopy, but no association of lichen spinulosus with atopy was found in the Philippines. A report notes a family with lichen spinulosus in 4 generations, an observation that suggests a genetic predisposition.
Differential Diagnoses
| Disseminate and Recurrent Infundibular
Folliculitis | Pityrosporum Folliculitis |
| Frictional lichenoid dermatitis of
children | Trichostasis spinulosa |
| Hypovitaminosis A phrynoderma | |
| Keratosis Pilaris | |
| Lichen nitidus |
Other Problems to Be Considered
Dermatophytosis
Frictional lichenoid eruption
Lichen scrofulosorum
Lichen nitidus5
Lymphoproliferative disorders (folliculotropic cutaneous T-cell lymphoma/follicular mucinosis6
HIV-associated pityriasis rubra pilaris (type VI) demonstrates lichen spinulosus
Workup
Laboratory Studies
Diagnosis should be made on clinical grounds alone. At present, no laboratory tests are specific or diagnostic for lichen spinulosus.
Histologic Findings
Histologic findings of lichen spinulosus are similar to those observed in keratosis pilaris. In lichen spinulosus, dilated hair follicles are filled with a keratotic plug. An inflammatory lymphocytic infiltrate occurs around the follicle and in the dermis. Hyperkeratosis, parakeratosis, and acanthosis may be present in the follicle.
Treatment
Medical Care
No cure exists for lichen spinulosus, but some medications ameliorate its clinical manifestations. Because of the horny plug, keratolytics have been used as a treatment. These include salicylic acid, lactic acid, and/or urea in various creams, ointments, gels, and lotions.7 The literature does not support the use of topical steroids in lichen spinulosus. The combination of tretinoin gel at bedtime with hydroactive adhesives the following morning has been reported to be efficacious.8
Consultations
Consultation with an experienced dermatologist is indicated if any doubt exists concerning the diagnosis.
Medication
The goal of treatment for lichen spinulosus is to improve the cosmetic disfigurement caused by the disorder.
Keratolytic agents
Topical lactic acid creams have provided the most successful therapy to date. Salicylic acid gel and urea containing lotions also have been reported to help soften the horny papules. Gentle abrasion with a pad, soft brush, or luffa pad can be tried to remove the horny spines.
Lactic acid (Lac-Hydrin)
Contains lactic acid, an alpha-hydroxy acid with keratolytic action, thus facilitating release of comedones. Available in 12% and 5% strengths. The 12% form may cause irritation on the face. Causes disadhesion of corneocytes. Found in a variety of topical emollient lotions.
May be combined with 10-20% urea cream or be used with salicylic acid gel.
Dosing
Adult
Apply topically qd/bid
Pediatric
Apply as in adults
Interactions
None reported
Contraindications
Documented hypersensitivity
Precautions
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
May sting or cause pain if applied on broken skin; may cause irritation with erythema, burning, and peeling if applied to face in 12% concentrations
Salicylic acid 6% (cream, lotion, or gel)
Beta-hydroxy acid reported to soften papules. By dissolving intercellular cement substance, produces desquamation of the horny layer of skin, while not affecting structure of viable epidermis. Comes as a cream, lotion, or gel.
Dosing
Adult
Apply topically several times/d
Pediatric
To avoid salicylate toxicity, use care when applying to large areas
Interactions
None reported
Contraindications
Documented hypersensitivity; prolonged use in infants and patients with diabetes or impaired circulation; use on moles, birthmarks, warts with hair growth, genital or facial warts, warts on mucous membranes, irritated skin, or infected or reddened areas
Precautions
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Avoid contact with mucous membranes; immediately flush with water for 15 min if contact with eyes or mucous membranes occurs
Urea 40% cream or lotion
Promotes hydration and removal of excess keratin.
Dosing
Adult
Apply prn to affected area
Pediatric
Apply as in adults
Interactions
None reported
Contraindications
Documented hypersensitivity; viral skin disease
Precautions
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Do not use near eyes; caution if applied to broken or swollen skin
Follow-up
Complications
Lichen spinulosus is confined to the skin and has no known associations with internal disorders or genetic syndromes.
Prognosis
Lichen spinulosus can be ameliorated using emollient keratolytics. Case reports suggest that cure is the result of spontaneous remission over time. Most cases appear to remit within 1-2 years; however, well-documented cases exist that have lasted for decades.
Miscellaneous
Medicolegal Pitfalls
Failure to diagnose lichen spinulosus correctly may result in years of ineffective treatment.9,10
Multimedia
Media file 1: Lichen spinulosus on the abdomen.
Media file 2: Close-up view.
References
Friedman SJ. Lichen spinulosus. Clinicopathologic review of thirty-five cases. J Am Acad Dermatol. Feb 1990;22(2 Pt 1):261-4. [Medline].
Cohen SJ, Dicken CH. Generalized lichen spinulosus in an HIV-positive man. J Am Acad Dermatol. Jul 1991;25(1 Pt 1):116-8. [Medline].
Kano Y, Orihara M, Yagita A, Shiohara T. Lichen spinulosus in a patient with Crohn's disease. Int J Dermatol. Sep 1995;34(9):670-1. [Medline].
Kabashima R, Sugita K, Kabashima K, Nakamura M, Tokura Y. Lichen spinulosus in an alcoholic patient. Acta Derm Venereol. 2009;89(3):311-2. [Medline].
Tilly JJ, Drolet BA, Esterly NB. Lichenoid eruptions in children. J Am Acad Dermatol. Oct 2004;51(4):606-24. [Medline].
Cömert A, Akin O, Demirkesen C. Follicular mucinosis mimicking lichen spinulosus in an 11-year-old boy. Eur J Dermatol. Nov-Dec 2007;17(6):544-5. [Medline].
Maiocco KJ, Miller OF. Lichen spinulosus: response to therapy. Cutis. Feb 1976;17(2):294-99. [Medline].
Forman SB, Hudgins EM, Blaylock WK. Lichen spinulosus: excellent response to tretinoin gel and hydroactive adhesive applications. Arch Dermatol. Jan 2007;143(1):122-3. [Medline].
Boyd AS. Lichen spinulosus: case report and overview. Cutis. Jun 1989;43(6):557-60. [Medline].
Tilly JJ, Drolet BA, Esterly NB. Lichenoid eruptions in children. J Am Acad Dermatol. Oct 2004;51(4):606-24. [Medline].
Keywords
lichen spinulosus, keratosis follicularis spinulosa, lichen pilaris seu spinulosus of Crocker, keratosis follicularis spinosa of Unna
Contributor Information and Disclosures
Author
Stephen W White, MD, Clinical Assistant Professor, Department of Dermatology, George Washington University Hospital; Chief, Sub-section of Dermatology, Suburban Hospital
Stephen W White, MD is a member of the following medical societies: American Academy of Dermatology, International Society of Dermatology, Society for Investigative Dermatology, and Society for Pediatric Dermatology
Disclosure: Nothing to disclose.
Coauthor(s)
Christopher R Gorman, MD, Bethesda Dermatology, private practice
Christopher R Gorman, MD is a member of the following medical societies: Alpha Omega Alpha
Disclosure: Nothing to disclose.
Medical Editor
James J Nordlund, MD, Professor Emeritus, Department of Dermatology, University of Cincinnati College of Medicine
James J Nordlund, MD is a member of the following medical societies: American Academy of Dermatology, Sigma Xi, and Society for Investigative Dermatology
Disclosure: Nothing to disclose.
Pharmacy Editor
Richard P Vinson, MD, Assistant Clinical Professor, Department of Dermatology, Texas Tech University School of Medicine; Consulting Staff, Mountain View Dermatology, PA
Richard P Vinson, MD is a member of the following medical societies: American Academy of Dermatology, Association of Military Dermatologists, Texas Dermatological Society, and Texas Medical Association
Disclosure: Nothing to disclose.
Managing Editor
Rosalie Elenitsas, MD, Herman Beerman Associate Professor of Dermatology, University of Pennsylvania School of Medicine; Director, Penn Cutaneous Pathology Services, Department of Dermatology, University of Pennsylvania Health System
Rosalie Elenitsas, MD is a member of the following medical societies: American Academy of Dermatology and American Society of Dermatopathology
Disclosure: Nothing to disclose.
CME Editor
Catherine M Quirk, MD, Clinical Assistant Professor, Department of Dermatology, University of Pennsylvania
Catherine M Quirk, MD is a member of the following medical societies: Alpha Omega Alpha and American Academy of Dermatology
Disclosure: Nothing to disclose.
Chief Editor
Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center
Dirk M Elston, MD is a member of the following medical societies: American Academy of Dermatology
Disclosure: Nothing to disclose.