Hair Shaft Yellow Nodules in a Pediatric Female Patient

Trichoscopy in the Differential Diagnosis of Pseudonits

AIM

The purpose of the study was to describe the trichoscopic features of pseudonits and to assess the usefulness of trichoscopy in their differential diagnosis.

METHODS

A retrospective study was performed on those patients seen for the suspicion of head or pubic lice and who underwent trichoscopy with polarized light at ×10 magnification for a more accurate diagnosis. Forty-two patients (28 males/14 females, mean age: 34.5 years, range: 7-59) were evaluated.

RESULTS

In 30 cases, trichoscopy confirmed the suspicion of head (24 cases) or pubic (6 cases) lice, whereas in 12 cases it allowed for a final diagnosis of seborrheic dermatitis (5 cases), hair casts (3 cases), trichobacteriosis (2 cases), white piedra (1 case), and trichorrhexis nodosa (1 case), by showing different types of pseudonits.

CONCLUSION

Hair examination using trichoscopy in routine clinical practice may provide useful information for the correct diagnosis, ranging from common head and pubic lice infestations to rarer shaft abnormalities. Differentiating pseudonits from nits is essential to make the correct diagnosis in order to prevent unnecessary treatment, anxiety, and/or embarrassment.

White Piedra: Clinical, Mycological, and Therapeutic Experience of Fourteen Cases

Background

White piedra (WP) is an asymptomatic superficial mycosis that affects the hair stems, forming whitish nodules caused by various species of the genus Trichosporon.

Objective

To present a case series of WP of the head, its epidemiological data, as well as clinical, mycological, and therapeutic experience.

Methods

We conducted a 12-year retrospective and observational study of WP cases tested by dermoscopy, mycological study, and the identification of species through morphology, biochemistry, and proteomics (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry). The treatment was based on ketoco-nazole shampoo as well as keratolytics.

Results

We included 14 cases of WP, all located in the head and 1 case with both head and scrotum affected. Nine cases (64.3%) presented in children aged < 15 years. The majority of the cases (13/14, 92.8%) were women. Two cases were associated with hyperkeratosis and intertrigo. Most patients had long hair and excessive moisture. In all cases hair nodules were observed and Trichosporon inkin (11/14, 78.6%) was usually isolated. Eleven cases (78.6%) were cured by administering 2% ketoconazole shampoo.

Conclusion

WP was observed in school-age girls. The diagnosis was based on the observation of hair nodules and its main etiologic agent was T. inkin, with good response to treatment in most cases.

Dermatoscopy of Parasitic and Infectious Disorders

The use of dermatoscopy in the diagnosis and management of parasitic and infectious skin disorders has been defined as entodermoscopy, and several studies have confirmed its advantages in dermatology. Dermatoscopic patterns of several parasitic, viral, and fungal skin infections have been identified and herein described. A noninvasive, fast, and accurate diagnosis plays an important role in containing the spread of contagious skin disorders.