| Patient Education |
|
Click here for patient education.
|
|
You are in: eMedicine Specialties >
Dermatology > DISEASES OF THE ADNEXA
Loose Anagen Syndrome
Article Last Updated: Oct 19, 2006
AUTHOR AND EDITOR INFORMATION
Section 1 of 10  
Author: Supriya Goyal, MD, Consulting Dermatologist
Supriya Goyal is a member of the following medical societies: Alpha Omega Alpha
Coauthor(s):
Robert A Schwartz, MD, MPH, Professor and Head of Dermatology, Professor of Medicine, Professor of Pediatrics, Professor of Pathology, Professor of Preventive Medicine and Community Health, UMDNJ-New Jersey Medical School
Editors: Leonard Sperling, MD, Chair, Professor, Department of Dermatology, Uniformed Services University of the Health Sciences; David F Butler, MD, Professor of Dermatology, Texas A&M University College of Medicine; Director, Division of Dermatology, Scott and White Clinic; Director Dermatology Residency Training Program, Scott and White Clinic; Paul Krusinski, MD, Director of Dermatology, Professor, Department of Internal Medicine, Fletcher Allen Health Care, University of Vermont; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center
Author and Editor Disclosure
Synonyms and related keywords:
loose anagen hair syndrome, short anagen syndrome, loose anagen hair of childhood, easily pluckable hair
Background
Loose anagen syndrome was first described in 1984. It is a hair disorder characterized by anagen hairs of abnormal morphology that are easily and painlessly pulled or plucked from the scalp. Hair is thinned in appearance and typically does not grow beyond the nape of the neck.
Pathophysiology
The precise pathogenesis of loose anagen syndrome is not known, but theories postulating an abnormality in the hair's anchoring mechanism predominate.
The inner root sheath is thought to play an integral role in anchoring the hair shaft within the follicle. In loose anagen syndrome, mutations in genes coding for cytokeratins have been identified in some cases and are thought to result in abnormal keratinization of the inner root sheath. This faulty keratinization leads to impaired adherence of the deformed hair shafts to their follicles. The impaired attachment may result in premature cessation of the anagen phase and account for reduced hair length. One author has also reported reduced follicle size due to delayed maturation. This may be responsible for sparse hair growth.
Frequency
United States
The prevalence of loose anagen syndrome is unknown. Although recently described, loose anagen syndrome may actually be rather common. It is undoubtedly often misdiagnosed as alopecia areata or trichotillomania. It has likely been both underdiagnosed and underreported to date.
Mortality/Morbidity
The diffuse hair loss that occurs in loose anagen syndrome often raises considerable concern among patients, parents, and clinicians. Although no treatment is currently available, the condition is of cosmetic significance only, and symptoms generally improve over time.
Race
Loose anagen syndrome has been reported only in white persons.
Sex
The syndrome is more common in females than in males.
Age
The classic patient with loose anagen syndrome is a girl aged 2-5 years with blonde hair; however, cases of loose anagen syndrome in boys, in adults, and in individuals with dark hair have also been reported.
History
- Parents often report that the child's hair is thinning and that haircuts are never needed or are needed only very infrequently.
- Parents may have noticed that hair traction, either accidental during playing or intentional, yields clumps of painlessly removed hair.
- Many parents complain that hair is unmanageable, lusterless, dry, dull, or matted.
- Parents or siblings occasionally have a history of similar symptoms.
- Children who are affected are healthy and free from underlying nutritional deficiencies or other illnesses.
- Growth and development are normal.
Physical
- Physical examination reveals sparse growth of thin, fine hair and diffuse or patchy alopecia without inflammation or scarring.
- Gentle traction results in hair that is painlessly removed; however, hair is not fragile or easily breakable.
- Hair may be of varying lengths and may have an unkempt, lackluster appearance.
- In particular, hair overlying the occiput tends to be rough or sticky and does not lie flat (see Image 1).
- No scalp inflammation or scarring is present.
- Eyebrows, eyelashes, and body hair are rarely involved.
- Other structures of ectodermal origin (eg, skin, teeth, nails) are not affected.
Causes
Although its occurrence is typically sporadic, familial cases of loose anagen syndrome have been observed. Inheritance appears to be in an autosomal dominant pattern with variable penetrance. Loose anagen syndrome has not been consistently associated with any other disorder; however, individual cases associated with the following syndromes have been reported. These associations were most likely coincidental.
- Noonan syndrome
- Ocular coloboma syndrome
- Trichorhinophalangeal syndrome
- Nail-patella syndrome
- Hypohidrotic ectodermal dysplasia and ectrodactyly-ectodermal dysplasia-clefting syndrome
- Acquired immunodeficiency syndrome
- Woolly hair
- Alopecia areata
- Loose anagen syndrome with features resembling uncombable hair syndrome
- Colobomas and dysmorphic features including low-set ears, hypertelorism, left microphthalmia, frontal bossing, a thin upper lip, a simple philtrum, and slight left facial hypoplasia
- Noonan-like syndrome characterized by short stature, a distinctive facial phenotype, macrocephaly, enlarged cerebral spinal fluid spaces, a short neck with redundant skin, severe growth hormone deficiency, mild psychomotor delay with attention deficit/hyperactivity disorder, and increased skin pigmentation
Alopecia Areata
Lupus Erythematosus, Acute
Lupus Erythematosus, Discoid
Pseudopelade, Brocq
Telogen Effluvium
Tinea Capitis
Trichotillomania
Other Problems to be Considered
Lichen planopilaris
Traction alopecia
Hypothyroidism
Hyperthyroidism
Iron deficiency anemia
Medication-induced hair loss (most commonly from chemotherapeutic agents, gout medications, vitamin A, oral contraceptives, and antidepressants)
Other Tests
- The normal scalp cycle is divided into 3 phases: the active growth anagen phase, followed by a brief catagen phase, and finally the resting telogen phase.
- Typically, 85-95% of hairs are in the anagen phase, which lasts about 3 years.
- Less than 1% of hairs are in catagen, the transitional phase, which lasts from a few days to weeks.
- The telogen phase, which accounts for 5-15% of hairs and lasts about 3 months, ends when the new anagen hair emerges from the follicle. A telogen count of 20% is considered the upper limit of normal.
- In healthy individuals, removing hair with light traction yields few hairs, almost all of which are in the telogen phase. These hairs are readily identified by their dry, nonpigmented, clublike roots and the absence of an inner and outer root sheath.
- The diagnosis of loose anagen syndrome is confirmed by firmly pulling locks of hair (the gentle hair pull) and by microscopically examining those extracted hairs. A gentle hair pull normally yields only 0-2 hairs per pull, but, in loose anagen syndrome, the number extracted may be much higher. Patients with loose anagen syndrome feel no discomfort as hairs are extracted.
- In normal individuals, only telogen hairs are extracted during a gentle hair pull. The presence of anagen hairs on a gentle pull test, as found in loose anagen syndrome, is pathologic. Easily extractable hairs may be seen in active lesions of lupus erythematosus or lichen planopilaris. They differ from the hairs of loose anagen syndrome in that they lack the characteristic "rumpled sock" cuticle.
- Forcible plucking with a hemostat in patients with loose anagen syndrome also results in easy and painless hair extraction. The hair is not fragile, and plucking does not cause breaks within the hair shaft.
- Under light microscopy, the epilated hairs are predominantly in anagen phase.
- The proximal end demonstrates a distorted hair bulb that is often bent at an acute angle to the hair shaft.
- The hair bulb may also appear long and tapered or twisted in relation to the long axis of the hair shaft.
- The hairs lack an inner and outer root sheath, and the cuticle has a characteristic rippled or ruffled, sawtooth, baggy-stocking appearance (rumpled sock appearance) (see Image 2).
- On scanning electron microscopy, loose anagen hairs may demonstrate abnormal ridging and fluting of the hair shaft.
- Trichograms (forcible hair plucks) reveal an abnormally large percentage of anagen hairs lacking inner and outer sheaths. Few or no telogen hairs are present.
Histologic Findings
Although a scalp biopsy is not indicated to diagnose loose anagen syndrome, a few investigators have reported histologic findings. However, the histologic features of loose anagen syndrome have not yet been critically studied.
Cleft formations between hair shafts and inner root sheaths and fragmentation of the inner root sheaths may be visualized. Regressive changes of the inner root sheath, including homogenization and crumbly degeneration, may be seen, particularly on transversely cut biopsy specimens. Loose anagen hairs may demonstrate abnormal configurations on cross-section rather than the typical round or oval shape seen in normal hair shafts.
Anagen follicles showing premature keratinization in the cells of Henle and Huxley layers have been reported in hairs from patients with loose anagen syndrome. Although keratinization occurs at more distal areas of the follicle in normal anagen hairs, it may be seen at the lower bulbar level in loose anagen hairs.
Notably, no inflammatory infiltrates are present in loose anagen syndrome.
Medical Care
No therapy is currently available for loose anagen syndrome. Reassure the patient's parents and adults who are affected that the syndrome is of cosmetic significance only and usually improves with increasing age.
Activity
Careful and gentle grooming may help to minimize hair loss.
Prognosis
- In individuals who are affected, hair typically increases in length and density over time and darkens in color; however, the loose anagen characteristic persists and hair continues to be easily and painlessly pulled from the scalp.
Medical/Legal Pitfalls
- In patients with hair loss, a careful history, physical examination, and microscopic examination of extracted hairs should be conducted to rule out loose anagen syndrome. Patients in whom the diagnosis is missed may undergo an unnecessary biopsy, or they may be started on treatments with potentially adverse effects.
- Results of the hair pull test in some patients with loose anagen syndrome have been reported to vary over time, including periods of time in which no hairs can be extracted. Therefore, a single negative hair pull test does not conclusively rule out loose anagen syndrome. In cases where history and clinical findings are suggestive of loose anagen syndrome but results of the hair pull test are negative, trichogram of forcibly plucked hairs or repeating the hair pull test at regular intervals can establish the diagnosis.
| Media file 1:
Thinning, dull, lackluster blonde hair with matting over the occipital region. |
 |  View Full Size Image | |
Media type: Photo
|
| Media file 2:
Microscopic view of easily plucked hair demonstrating a distorted anagen bulb lacking inner and outer root sheaths, and a ruffled, sawtooth, baggy-stocking appearance of the cuticle (original magnification X100). |
 | View Full Size Image | |
Media type: Photo
|
- Azon-Masoliver A, Ferrando J. Loose anagen hair in hypohidrotic ectodermal dysplasia. Pediatr Dermatol. Jan-Feb 1996;13(1):29-32. [Medline].
- Baden HP, Kvedar JC, Magro CM. Loose anagen hair as a cause of hereditary hair loss in children. Arch Dermatol. Oct 1992;128(10):1349-53. [Medline].
- Boyer JD, Cobb MW, Sperling LC, Rushin JM. Loose anagen hair syndrome mimicking the uncombable hair syndrome. Cutis. Feb 1996;57(2):111-2. [Medline].
- Chapalain V, Winter H, Langbein L, et al. Is the loose anagen hair syndrome a keratin disorder? A clinical and molecular study. Arch Dermatol. Apr 2002;138(4):501-6. [Medline].
- Chapman DM, Miller RA. An objective measurement of the anchoring strength of anagen hair in an adult with the loose anagen hair syndrome. J Cutan Pathol. Jun 1996;23(3):288-92. [Medline].
- Chong AH, Sinclair R. Loose anagen syndrome: a prospective study of three families. Australas J Dermatol. May 2002;43(2):120-4. [Medline].
- Garcia-Hernandez MJ, Price VH, Camacho FM. Woolly hair associated with loose anagen hair. Acta Derm Venereol. Sep-Oct 2000;80(5):388-9. [Medline].
- Hamm H, Traupe H. Loose anagen hair of childhood: the phenomenon of easily pluckable hair. J Am Acad Dermatol. Feb 1989;20(2 Pt 1):242-8. [Medline].
- Hansen LK, Brandrup F, Clemmensen O. Loose anagen hair syndrome associated with colobomas and dysmorphic features. Clin Dysmorphol. Jan 2004;13(1):31-2. [Medline].
- Haskett M. Loose anagen syndrome. Australas J Dermatol. Feb 1995;36(1):35-6. [Medline].
- Khadir K, Habibeddine S, Azzouzi S, et al. [Loose anagen hair syndrome: a familial case with fetal hair in meconium]. Ann Dermatol Venereol. Jan 2001;128(1):52-4. [Medline].
- Lee AJ, Maino KL, Cohen B, Sperling L. A girl with loose anagen hair syndrome and uncombable, spun-glass hair. Pediatr Dermatol. May-Jun 2005;22(3):230-3. [Medline].
- Li VW, Baden HP, Kvedar JC. Loose anagen syndrome and loose anagen hair. Dermatol Clin. Oct 1996;14(4):745-51. [Medline].
- Martinez JA, Velasco M, Vilata JJ, et al. Loose anagen syndrome: a new case. Acta Derm Venereol. Nov 1994;74(6):473. [Medline].
- Mazzanti L, Cacciari E, Cicognani A, et al. Noonan-like syndrome with loose anagen hair: a new syndrome?. Am J Med Genet. Apr 30 2003;118A(3):279-86. [Medline].
- Murphy MF, McGinnity FG, Allen GE. New familial association between ocular coloboma and loose anagen syndrome. Clin Genet. Apr 1995;47(4):214-6. [Medline].
- O''Donnell BP, Sperling LC, James WD. Loose anagen hair syndrome. Int J Dermatol. Feb 1992;31(2):107-9. [Medline].
- Pride HB, Tunnessen WW Jr. Picture of the month. Loose anagen syndrome. Arch Pediatr Adolesc Med. Jul 1995;149(7):819-20. [Medline].
- Sinclair R, Cargnello J, Chow CW. Loose anagen syndrome. Exp Dermatol. Aug 1999;8(4):297-8. [Medline].
- Skelsey MA, Price VH. Noninfectious hair disorders in children. Curr Opin Pediatr. Aug 1996;8(4):378-80. [Medline].
- Smith VV, Anderson G, Malone M, Sebire NJ. Light microscopic examination of scalp hair samples as an aid in the diagnosis of paediatric disorders: retrospective review of more than 300 cases from a single centre. J Clin Pathol. Dec 2005;58(12):1294-8. [Medline].
- Sullivan JR, Kossard S. Acquired scalp alopecia. Part I: A review. Australas J Dermatol. Nov 1998;39(4):207-19; quiz 220-1. [Medline].
- Thai KE, Sinclair RD. Loose anagen syndrome as a severity factor for trichotillomania. Br J Dermatol. Oct 2002;147(4):789-92. [Medline].
- Thomas L, Robart S, Balme B, Moulin G. [Loose anagen hair syndrome]. Ann Dermatol Venereol. 1993;120(8):535-7. [Medline].
- Tosti A, Peluso AM, Misciali C, et al. Loose anagen hair. Arch Dermatol. Sep 1997;133(9):1089-93. [Medline].
- Tosti A, Misciali C, Borrello P, et al. Loose anagen hair in a child with Noonan''s syndrome. Dermatologica. 1991;182(4):247-9. [Medline].
- Tosti A, Piraccini BM. Loose anagen hair syndrome and loose anagen hair. Arch Dermatol. Apr 2002;138(4):521-2. [Medline].
Loose Anagen Syndrome excerpt Article Last Updated: Oct 19, 2006
|
