Trichorrhexis nodosa with nail dystrophy: diagnosis by dermoscopy.

A 25-year-old male, born of non-consanguineous marriage presented with complaints of sparse and thin hairs over scalp and dystrophy of nails since childhood. This case highlights the association of trichorrhexis nodosa with nail dystrophy and the use of trichoscopy as a noninvasive method for diagnosis of hair disorders.

INTRODUCTION

Trichorrhexis nodosa (TN) is the most common hair shaft anomaly, caused by either physical or chemical trauma. It presents with minute grayish nodes along hair shaft and characteristic “thrust paint brushes” appearance on microscopy. It may be congenital or acquired.[12] We report a case of congenital TN with nail dystrophy and emphasize importance of trichoscopy in hair shaft disorders.

CASE REPORT

A 25-year-old male, otherwise healthy, presented with diffuse thinning of hair over scalp, especially of the vertex and occipital area, since childhood. He also complained that the nails had an abnormal morphology and had showed inadequate growth since childhood. There were no similar complaints in the family and he had no associated primary dermatologic ailments. He also denied history of any chemical trauma to hairs. There was no history suggestive of any neurological disorder.

Cutaneous examination revealed sparse, fragile, and thin hairs over scalp, specially vertex and occipital area [Figure 1], and dystrophy of all finger [Figure 2] and toe nails with thickened nail plates, ridging and distal onycholysis. Beard, moustache, eyebrow, and axillary hairs appeared to be normal clinically. Mucosae, teeth, and sweating were normal. Rest of the cutaneous examination was also normal. Systemic examination was also within normal limits.

Figure 1

Thin and sparse hairs with alopecia over vertex and occipital area, with relative sparing of frontal hairs

Figure 2

Dystrophy of bilateral finger nails with distal onycholysis and short nail plates

We did trichoscopic examination of scalp hairs. It showed fraying of cortical fibers resulting in “thrust paint brushes” appearance. Both proximal and distal hair shaft breakage was seen [Figure 3]. Hairs from vertex, occipital area, beard, and eyebrow showed similar features on trichoscopy. Routine blood chemistry including hemogram, total and differential leucocyte count, liver and kidney function tests, and routine urine examination was normal. Patient refused a scalp biopsy.

Figure 3

Trichoscopic image showing breakage in hair shafts at multiple levels with characteristic “thrust paint brushes” appearance (Trichoscopy, white light ×40)

Based on above history, examination, and trichoscopic finding, a diagnosis of TN with 20 nail dystrophy was made.

DISCUSSION

TN, the most common hair shaft disorder, appears as minute grayish nodes along the hair shaft. These nodes represent loss of cuticle along with frayed cortical fibers. On light microscopy, these changes appear like two paint brushes thrust into one another.[12]

TN may be congenital or acquired, localized or generalized. Congenital TN may be present at birth, appear within the first year of life, or present as a symptom of an underlying metabolic disorder like argininosuccinic aciduria, Menkes’ kinky hair syndrome, Netherton syndrome, and Laron syndrome at the age of 2 years or later. It affects beard, moustache, eyebrow, eyelashes, axillary and pubic hairs variably along with scalp hairs. Breakage of hair occurs both at proximal and distal shaft.[1-3]

Acquired TN usually occurs due to physical or chemical trauma to hairs and affects mostly scalp hairs only, with distal shaft breakage.[2]

In 1997, an apparently new autosomal dominantly inherited, pure hair–nail ectodermal dysplasia was reported with a mother and son having hypotrichosis of bilateral frontotemporal areas of the scalp with micronychia and onychorrhexis and the triangular nail plate. In 2004, Harrison and Sinclair reported a case with hypotrichosis and nail dysplasia in 3-year-old girl, as a form of novel hidrotic ectodermal dysplasia.[4] Our case has many similarities to these two cases.

Trichoscopy is one of the recent advances in diagnostic dermatology. It allows examination of subtle clinical patterns of skin lesions and subsurface skin structures not normally visible to the unaided eye. Trichoscopy has been used for rapid diagnosis of some hair shaft disorders like monilethrix. In our case, use of trichoscopy provided rapid and reliable diagnosis of TN.[5]

Thus, our case highlights TN with nail dysplasia and use of trichoscopy as a diagnostic modality for TN. We suggest that use of trichoscopy should be extended for diagnosis of hair disorders. Associated nail dystrophy in our case may be a form of some unidentified hidrotic ectodermal dysplasia.