Evaluation and Management of a New Bald Spot in a 10-Year-Old Girl
The most likely diagnosis is alopecia areata, which can be diagnosed clinically without laboratory testing in most cases, and watchful waiting with reassurance is a legitimate first-line approach since 34-50% of children with limited patchy hair loss recover spontaneously within one year. 1, 2
Initial Clinical Assessment
Key Diagnostic Features to Examine
Look for exclamation mark hairs at the margins of the bald patch—these are short broken hairs (2-3mm) that are pathognomonic for alopecia areata and can be identified with dermoscopy 1, 2
Assess the pattern of hair loss: discrete round or oval patches indicate alopecia areata, while incomplete hair loss with firmly anchored broken hairs suggests trichotillomania 1, 2
Check for scalp inflammation or scaling: if present, this suggests tinea capitis rather than alopecia areata, which typically shows smooth skin without inflammation 1, 2
Examine for yellow dots on dermoscopy: regular round yellow dots are commonly seen in active alopecia areata and indicate disease progression 1
Essential History Elements
Duration of hair loss: onset less than 1 year predicts better prognosis with potential spontaneous remission in 34-50% of cases 1, 2
Family history: approximately 20% of children with alopecia areata have a family history of the condition 1, 2
Assess for hair pulling behaviors: trichotillomania must be differentiated from alopecia areata, as management differs completely 1, 3
Laboratory Testing Strategy
Investigations are unnecessary in most cases when alopecia areata is clinically evident. 1, 2
When to Order Tests
Fungal culture: only if tinea capitis is suspected based on scalp inflammation or scaling 1, 2
Skin biopsy: reserved for uncertain diagnosis or suspected scarring alopecia 1, 2
Avoid routine autoimmune panels: the increased frequency of autoimmune disease in alopecia areata patients is insufficient to justify routine screening 1, 2
Treatment Algorithm
First-Line Approach: Watchful Waiting
For limited patchy alopecia areata (single or few patches), watchful waiting with reassurance is the recommended initial approach. 1, 2
Spontaneous remission occurs in 34-50% of patients within one year without any treatment 1, 2
Counsel that regrowth cannot be expected within 3 months of any individual patch development 1, 2
No treatment has been shown to alter the long-term course of alopecia areata, though some can induce temporary hair regrowth 1, 2
Second-Line: Active Treatment (If Desired)
If treatment is requested after discussion, intralesional corticosteroids are the most appropriate option for limited patchy disease. 1, 2
Use triamcinolone acetonide 5-10 mg/mL injected just beneath the dermis in the upper subcutis 1
Each 0.05-0.1 mL injection produces a tuft of hair growth approximately 0.5 cm in diameter, with effects lasting about 9 months 1
In one study, 62% of patients achieved full regrowth with monthly injections, with better response in those with fewer than five patches less than 3 cm in diameter 1
Main limitation is patient discomfort from multiple injections 1
Treatments to Avoid in Children
Potent topical corticosteroids lack convincing evidence of effectiveness for alopecia areata 1, 2
Systemic corticosteroids are not recommended due to potentially serious side-effects and inadequate efficacy evidence, though some recent data suggest oral betamethasone mini-pulses may have a role in severe cases 1, 4
Oral zinc and isoprinosine are ineffective in controlled trials 2
Psychological Support
Assessment of psychological impact is essential, as children with alopecia areata commonly experience self-consciousness, embarrassment, and bullying 1, 5
Psychological interventions should be offered to improve coping mechanisms 1
Parents should be offered psychological counseling as well 1
Wigs can provide immediate cosmetic benefit if hair loss is extensive or distressing 2
Common Pitfalls to Avoid
Do not order extensive autoimmune panels in straightforward alopecia areata cases—this is unnecessary and not recommended 1, 2
Do not miss trichotillomania: broken hairs in trichotillomania remain firmly anchored (still in anagen phase), unlike exclamation mark hairs in alopecia areata 1, 2
Do not promise rapid results: patients must understand that even with treatment, regrowth takes at least 3 months 1, 2
Do not use hazardous treatments of unproven efficacy: alopecia areata has no direct impact on general health that justifies risky interventions 1, 6
Prognosis Counseling
Patients with less than 25% hair loss initially have a 68% chance of being free of disease at follow-up 1
Long-standing extensive alopecia has a poor prognosis, and many patients prefer no active treatment other than wearing a wig 1, 6
Relapse can occur even after successful treatment, and patients should be forewarned about this possibility 6