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Dermoscopic features in Laugier-Hunziker syndrome
Article first published online: 23 NOV 2010
© 2010 Japanese Dermatological Association
The Journal of Dermatology
Special Issue: SPECIAL ISSUE: Dermoscopy (pages 1-75)
Volume 38, Issue 1, pages 87–90, January 2011
How to Cite
KO, J.-H., SHIH, Y.-C., CHIU, C.-S. and CHUANG, Y.-H. (2011), Dermoscopic features in Laugier-Hunziker syndrome. The Journal of Dermatology, 38: 87–90. doi: 10.1111/j.1346-8138.2010.01077.x
All Financial Interests: None to report.
- Issue published online: 22 DEC 2010
- Article first published online: 23 NOV 2010
Laugier-Hunziker syndrome is a rare, benign hyperpigmentation disorder, which is characterized by lenticular melanin pigmentation of the lips and oral mucosa. In addition, longitudinal melanonychia is occasionally observed.1 Dermoscopic examination is a non-invasive technique that provides an easy and simple tool for the diagnosis of Laugier-Hunziker syndrome.
Herein, we report the case of a patient with Laugier-Hunziker syndrome and the concurrent dermoscopic features. In 2003, a 58-year-old Chinese woman presented to our dermatology clinic with multiple melanotic macules on her lips and bilateral buccal mucosa. There had been longitudinal melanonychia on her left third finger since 2008. Several melanotic macules on her fingertips had also appeared in recent months. She had not taken any medication that could have caused the pigmented lesions. Moreover, there was no family history of mucocutaneous pigmentation or intestinal polyps. Physical examination showed multiple round- to ovoid-shaped, pea-sized blackish macules on her lips and buccal mucosa. In addition, there were several discrete, ovoid-shaped, brownish macules on her fingertips. No Hutchinson’s sign was noted on the left third finger, although homogenous brownish and greyish longitudinal lines and bands were present (Fig. 1a–d). Laboratory data showed that the levels of adrenocortin, cortisol, T3, free T4, and thyrotropin were all within normal limits. Panendoscopy and colofibroscopy revealed no intestinal polyposis. A skin biopsy was taken from her upper lip. Histopathologically, there were pigmented basal keratinocytes and scattered melanophages in the submucosa (Fig. 2a) with ectopic sebaceous glands. Dermoscopic examination disclosed a regular brownish reticulate pattern with linear or curvilinear vasculature in the buccal mucosa, a parallel ridge pattern on the ventral surface of the fingers, and homogeneous longitudinal brownish and greyish lines and bands with ill-defined margins on the left third fingernail (Fig. 2b–d). On the basis of these findings, the diagnosis of Laugier-Hunziker syndrome was made.
Clinically, this disorder is characterized by hyperpigmentation on the lips, oral mucosa, and nails.1,2 In 3% of the normal population, melanotic macules are the most common etiology of lip hyperpigmentation.2 These macules can be solitary, numerous, or confluent, and the color can be brown, black, or grey. These pigmented lesions have been reported to have ill-defined or sharply demarcated margins with round, ovoid, or lenticular shapes.3 The melanotic macules can be seen not only on the oral mucosa but also on the fingertips, plantar aspect of the soles, and, rarely, the oesophagus.4 Approximately 50–60% of patients with Laugier-Hunziker syndrome have longitudinal melanonychia of unknown etiology, but with no concurrent nail dystrophy.
Laugier-Hunziker syndrome is an important differential diagnosis of Peutz-Jeghers syndrome.5 Peutz-Jeghers syndrome is an autosomal dominant disorder, which is characterized by melanin pigmentation of the buccal mucosa or skin and hamartomatous intestinal polyposis. Giardiello et al.6 found that the cumulative risks for gastric cancer and cancer of the small intestine were 29% and 13%, respectively, in patients with Peutz-Jegher syndrome. In contrast to Peutz-Jeghers syndrome, there is no systemic involvement in patients with Laugier-Hunziker syndrome.
Histopathologically, there is increased pigmentation in the basal keratinocytes and melanin incontinence in the dermis with an increased number of melanophages. However, the number of melanocytes is unafftected.5
To the best of our knowledge, there have been few reports describing the dermoscopic features of pigmented lesions in patients with Laugier-Hunziker syndrome (Table 1).7–10 In 2002, Ronger et al.10 were the first to describe the unique patterns for differentiation from nail melanoma in 12 patients with Laugier-Hunziker syndrome, namely, thin longitudinal grey lines, homogeneous in thickness, colour and spacing, against a greyish background. However, medication-induced melanonychia, such as that induced by minocycline, zidovudine, and hydroxyurea, or ethnic-type melanonychia may have similar dermoscopic patterns. Gencoglan et al.9 presented the dermoscopic findings of pigmented lesions not only on the nails but also on the oral mucosa, genital mucosa, palms, and soles. On the nails, there were homogenous longitudinal pigmented bands with ill-defined borders. Further, a parallel furrow pattern with brownish dots on the lips, a parallel furrow pattern with linear or curvilinear streaks on the vulva, and a parallel furrow pattern on the palms and soles have also been reported. Although there is no systemic involvement, Simionescu et al.8 reported one case of mucosal melanoma on the upper lip associated with Laugier-Hunziker syndrome. Pigmented nodular lesions have a blue-white veil with a globular pattern and unusual vasculature, which indicate the presence of a mucosal melanoma. Nevertheless, benign pigmented macules have a brown regular reticular pattern. Tamiya et al.7 observed numerous brownish and grey-blue granules on a whitish-pink area with scattered linear and dotted vasculature on the lower lip, a parallel ridge pattern on the ventral aspect of the thumb, and thin and thick greyish longitudinal lines and bands on the nail plate. In our case, we observed a regular brownish reticular pattern associated with linear and curvilinear vasculature on the labiogingival area, a brownish parallel ridge pattern on the ventral aspect of the fingers, and homogeneous brownish to greyish pigmented lines and bands with indistinct borders on the nail plate.
|Case/reference||Oral mucosa||Acral limbs||Nail||Genital mucosa|
|Ronger et al.10||ND||ND||Regular thin longitudinal grey lines on a brown background||ND|
|Gencoglan et al.9||PFP with brown dots||PFP||Homogeneous regular pigmented bands with indistinct margin||PFP with linear or curvilinear streaks|
|Simionescu et al.8||Regular brown network with homogeneous blue area||ND||ND||ND|
|Tamiya et al.7||Brown and blue-grey granules on whitish-pink area||PRP||Regular thin and thick linear greyish lines and bands||ND|
|Present case||Regular brown reticular pattern with linear and curvilinear vasculature||PRP||Homogeneous brown to grey linear lines and bands with indistinct border||ND|
There is wide variation in dermoscopic patterns of the pigmentation in Laugier-Hunziker syndrome. On the glabrous skin, such as palms and soles, the melanocytic pigmentation in ridges or furrows could reflect parallel ridge or parallel furrow pattern. On the mucosal lesions, diffuse pigmented basal keratinocytes along the junction of mucosa and submucosa can correlate to the reticular pattern. Also, longitudinal melanonychia resulting from pigmented nail matrix can be compatible with regular and symmetric pigmented lines dermoscopically.
It is important for clinicians to make dermoscopical differential diagnoses on pigmentation in Laugier-Hunziker syndrome. Dermoscopical patterns of longitudinal melanonychia could represent various disease entities, such as (i) blood spots on subungual hemorrhage; (ii) longitudinal pigmented lines irregular in the width, spacing, color, thickness, parallelism with micro-Hutchinson sign on nail apparatus melanoma; and (iii) regular longitudinal pigmented lines on nail apparatus nevus.10 In Simionescu’s8 case associated with invasive mucosal melanoma, there were bizarre vasculature, blue-white veil and few atypical globules. In addition, atypical pigment network and streaks could be a hint of mucosal melanoma. Acral lentiginous melanoma is the most common type of melanoma in non-Caucasians that has diffuse variegate pigmentation, serrated pattern, multi-component pattern or atypical reticulated pattern. If there is doubtful finding under dermoscopic examination, immediate biopsy of pigmented lesions is necessary.
In conclusion, dermoscopic examination is a non-invasive procedure that has been used for more accurate diagnosis of pigmented lesions, whether on the mucosa or the skin. However, there have been few reports describing the dermoscopic findings of these lesions. It is an important finding that a mucosal melanoma could be associated with pigmented macules in a patient with Laugier-Hunziker syndrome. Through this report, we hope to convey the importance of the dermoscopic examination of pigmented lesions in cases of Laugier-Hunziker syndrome. Furthermore, accumulation of different findings of pigmented lesions in Laugier-Hunziker syndrome could contribute to a more accurate diagnosis in the future.