A hairy situation

A 3-year-old female presents to your office because her mother is extremely worried about “spreading hair loss.” She saw a naturopathic doctor who recommended — and charged for — a full panel of labs, explaining to the family, “This is obviously related to her diet.”

The lab studies, including complete blood count with differential, thyroid function tests, iron studies, zinc, copper and heavy metals, were all normal. The mother decided to get a “second opinion” when the selenium supplement she was told to take did nothing to alleviate the girl’s problem.

In your office, the mother anxiously details a specific instance when removing a barrette from the child’s hair resulted in “the hair coming out in a clump,” without the child even noticing. You learn that the child has experienced various degrees of hair loss during the past 6 to 8 months. The child does not seem at all bothered by the hair loss, and the mother denies witnessing the child scratching, tugging, twirling or manipulating the hair by hand.

On physical exam, you examine a healthy-appearing female who continues to be about 75 percentile for height and weight per her growth chart. She has blonde hair with diffuse-but-patchy areas of hair loss, mostly on her parietal and occipital scalp. Overall, you are struck by how matted and lackluster the child’s hair appears to be, especially in contrast to her mother’s “shampoo commercial” locks. You also notice that the affected areas consist of hairs of uneven length that do not lie flat, giving the child an almost unkempt look (see Figures 1 and 2). Inflammation, scale, excoriations and scarring are not appreciated. There is no sign of nits or hair casts. Her eyelashes and eyebrows appear normal. Conjunctivae are without jaundice or pallor. Palpation of the thyroid reveals no nodules or fullness. Her teeth are normal, and her fingernails are without pits. There is no lymphadenopathy. The remainder of her physical exam is completely normal.

You decide to perform a gentle hair pull test, which yields 10 fine, dull blonde hairs of various lengths. Notably, the child does not flinch with the maneuver, and the hairs are plucked easily and without breakage within the hair shafts themselves. Under light microscopy, nine of the epilated hairs are in anagen phase and the remaining hair is in telogen phase. Several hairs demonstrate a distorted pigmented bulb bent at an acute angle to the hair shaft. Almost all of the anagen hairs are noted to have a ruffled, saw-tooth, “rumpled sock” appearance to them (see Figure 3; arrows point to saw-toothing and rumpled-sock appearance of ruffled cuticle).

Based on these findings, you drastically narrow your differential diagnosis. Which of the following questions would most likely help you to confirm the diagnosis?

1. Has the child suffered a “life stressor” (illness, new school, etc) in the 2 to 4 months preceding the hair loss?
2. How frequently does the affected child need to have her hair cut?
3. How often does the patient wear her hair in tight braids?
4. What pets are in the house or in contact with the child on a regular basis?
5. How much did that appointment to the naturopath and subsequent lab workup cost, and did insurance cover the expense?

Question No. 1 seeks to reveal a history consistent with telogen effluvium. Normally, only telogen hairs are extracted during a gentle hair pull. The overwhelming and unusual presence of anagen hairs and the virtual absence of telogen hairs argue against this diagnosis. Question No. 3 seeks to ascertain a history of traction alopecia. Depending on hairstyle, this condition may be characterized by oval or linear areas of hair loss at the margins of the hairline, along the part or scattered throughout the scalp. The history helps exclude this diagnosis. Question No. 4 is relevant to the diagnosis of tinea capitis, specifically by Microsporum species. There is no evidence of scale, inflammation or cervical chain lymphadenopathy, which make this diagnosis unlikely. Question No. 5 is somewhat “tongue in cheek,” but is directly relevant to this case because hair loss can create anxiety, driving patients and families to tremendous lengths. Because specific lab abnormalities, underlying nutritional deficiencies and other illnesses are not usually associated with the girl’s correct diagnosis, the cost of an extensive workup could have — and should have — been avoided.

That leaves Question No. 2, which elicits a history of infrequent haircuts — a clue to possible loose anagen syndrome.

The average human scalp contains about 100,000 hairs, with the hair shafts themselves representing the equivalent of the stratum corneum of the skin. Scalp hairs grow at a rate of about 1 cm per month, and, normally, about 100 hairs are shed and replaced each day. The hair cycle itself follows three definable phases of growth:

• Anagen: This is the active regular growth phase of the hair cycle. As new hairs grow in anagen phase, they push out the old telogen hairs that remain in the resting follicles. This phase of the growth cycle can last from about 2 to 6 years but averages about 3 years in duration. In those who are healthy, about 80% to 90% of the scalp’s terminal hairs are in this phase. Visualized under light microscopy, anagen hairs have pigmented bulbs and are normally surrounded by a gelatinous root sheath.
• Catagen: This phase is a transitional phase that typically lasts up to 3 weeks. It involves the hairs undergoing partial degeneration as they enter telogen phase and marks the period in which all growth activity ceases. Only about 5% of all scalp hairs are in catagen phase at any given time.
• Telogen: This is the resting phase of the hair cycle at the end of which new hair growth is initiated. Typically, telogen phase accounts for about 10% to 15% of all scalp hairs and lasts for about 3 months. Visualized under light microscopy, telogen hairs have a visible depigmented club-shaped bulb and lack a root sheath.

Diagnosis

Loose anagen syndrome (loose anagen hair of childhood) is a hair disorder characterized by loosely anchored anagen hairs that are easily and painlessly pulled from the scalp. Price first described the condition in 1989. The exact prevalence is unknown due in part to the fact that it is often misdiagnosed as telogen effluvium, alopecia areata or trichotillomania.

The condition seems to be inherited on an autosomal dominant basis with variable penetrance, such that a positive family history may be present. Although the precise pathogenesis of loose anagen syndrome remains unknown, ultrastructural studies of several affected patients’ hairs have demonstrated abnormal cornification of the inner root sheath. Faulty keratinization, secondary to mutations in genes coding for cytokeratins, may lead to impaired anchoring of the deformed hair shafts to their follicles with subsequent shortening of anagen phase. This may account for reduced hair length and sparse hair growth.

The “classic” loose anagen patient is a Caucasian girl with blonde hair, 2 to 5 years of age, with patchy or subtle diffuse thinning of the hair of the scalp. However, cases have been reported in boys, adults and in patients with dark hair. Hairs may be of uneven lengths and may appear dull and limp. Pulling of the hair, intentional or otherwise, may produce easily and painlessly removed clumps of fine hair. Parents often report that the affected child’s hair requires only very infrequent cutting or none at all. Loose anagen syndrome is a non-scarring alopecia, and inflammation or scarring of the scalp is not present. Eyebrows and eyelashes are usually unaffected.

Gentle pulling of the hair yields a predominance of anagen hairs. Under normal light microscopy, most of these hairs will demonstrate the characteristic rumpled or floppy sock appearance of the cuticles and pigmented misshapen bulbs. Because shedding of the hair is cyclic, the inability to extract numerous hairs on gentle pull test does not definitively rule out the diagnosis; serial exams should be performed if the diagnosis is in question.

Histologic examination reveals a lack of inflammatory infiltrates, and scanning electron microscopy of affected hairs may demonstrate abnormal ridging of the hair shaft; such rigorous testing, however, is rarely necessary to make this diagnosis.

Although the patchy or diffuse hair loss of loose anagen syndrome may cause considerable anxiety among patients and families, it is reassuring that other abnormalities are not typically associated with this disorder. Most importantly, those affected tend to see improvements in hair length and hair density with increasing age, such that no specific treatment is indicated. Gentle grooming should be encouraged to help minimize hair loss, and hairstyles that place undue stress on scalp hairs should be avoided.

For more information:

• Baden HP. Arch Dermatol. 1992;128:1349-1353.
• Chapalain V. Arch Dermatol. 2002;138:501-506.
• Chapman DM. J Cutan Pathol. 1996;23:288-292.
• Chong AH. Australas J Dermatol. 2002;43:120-124.
• Hamm H. J Am Acad Dermatol. 1989;20:242-248.
• Li VW. Dermatol Clin. 1996;14:745-751.
• Martínez JA. Acta Derm Venereol. 1994;74:473.
• Mirmirani P. J Am Acad Dermatol. 2011;64:129-134.
• O’Donnell BP. Int J Dermatol. 1992;31:107-109.
• Price VH. J Am Acad Dermatol. 1989;20:249-256.
• Tosti A. Arch Dermatol. 2002;138:521-522.

Disclosure: Dr. Krakowski reports no relevant financial disclosures.

Andrew C. Krakowski, MD, completed a residency in pediatrics at Johns Hopkins Medical Institute and a residency in dermatology at University of California, San Diego. He is currently a fellow in pediatric dermatology at Rady Children’s Hospital, San Diego. Catch him on Outdoor Channel as the host of boonDOCS Wilderness & Travel Medicine Show (email:dr.k@boonDOCSmedicine.com). Disclosure: Dr. Krakowski reports no relevant financial disclosures.

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