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Setting reference values in trichology.

Alfredo Rebora1, Marcella Guarrera1, Francesco Drago1

  • 1DISSAL, Section of Dermatology, IRCCS Azienda Universitaria Ospedaliera San Martino-IST, Genoa, Italy.

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Summary
This summary is machine-generated.

Prepubertal children may offer reliable reference values for hair density and diameter ratios, aiding in the diagnosis of androgenetic alopecia (AGA). Lower vertex/occiput ratios in children could indicate a 95% probability of AGA.

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Area of Science:

  • Clinical Trichology
  • Dermatology
  • Genetics

Background:

  • Arbitrary reference values in clinical trichology complicate diagnosis.
  • Androgenetic alopecia (AGA) genotype presence in subclinical cases poses diagnostic challenges.
  • Prepubertal children, lacking 5α-reductase, may provide AGA-independent reference values.

Purpose of the Study:

  • To evaluate vertex/occiput (V/O) ratios of hair density and diameter as reliable parameters for diagnosing androgenetic alopecia (AGA).
  • To establish normative V/O ratios in prepubertal children, independent of AGA influence.

Main Methods:

  • Studied 60 Caucasian children aged 4-10 years.
  • Measured vertex/occiput (V/O) ratios for both hair density and hair diameter.
  • Assessed hair shedding using hair pull and modified wash tests.

Main Results:

  • The average V/O of hair density was 1.07 ± 0.17.
  • The average V/O of hair diameter was 1.02 ± 0.11.
  • Normal V/O density ranged from 0.73 to 1.41; normal V/O diameter ranged from 0.8 to 1.24.

Conclusions:

  • Established normative ranges for V/O hair density and diameter in children.
  • Identified V/O ratios below 0.73 (density) or 0.8 (diameter) as indicative of a 95% probability of AGA.
  • Determined normal daily hair shedding to be 1-2 hairs.