International Journal of Health & Allied Sciences

CASE REPORT
Year
: 2017  |  Volume : 6  |  Issue : 3  |  Page : 191--193

Pachyonychia congenita affecting nails only: A sporadic case or novel mutation of an uncommon genodermatoses


Yadalla Hari Kishan Kumar, Shankar Keerthi 
 Department of Dermatology, Rajarajeswari Medical College and Hospital, Bengaluru, Karnataka, India

Correspondence Address:
Yadalla Hari Kishan Kumar
Skin Care Clinic, 70, Padma Nivasa, 3rd Cross MG Extension, HV Halli, Rajarajeswari Nagar, Bengaluru - 560 098, Karnataka
India

Abstract

Pachyonychia congenita (PC) is a rare genodermatoses transmitted by autosomal dominant inheritance characterized by hypertrophic nail changes and nail dystrophy, also associated with the oral mucosa, skin, hair, and teeth involvement. A 26-year-old female presented with disfigured nails of both hands and feet involving all 20 digits since birth. She gave complaints of occasional painful swelling and shedding of nails. The nails were discolored and thickened with overcurvature and subungual hyperkeratosis giving a characteristic wedge-shaped appearance. Palms, soles, and mucous membrane examination were normal. There were no other ectodermal abnormalities, and systemic examination was normal. Potassium hydroxide examination of the nail clippings did not reveal any fungi. The presence of characteristic clinical features led to a diagnosis of forme fruste of PC.



How to cite this article:
Kishan Kumar YH, Keerthi S. Pachyonychia congenita affecting nails only: A sporadic case or novel mutation of an uncommon genodermatoses.Int J Health Allied Sci 2017;6:191-193


How to cite this URL:
Kishan Kumar YH, Keerthi S. Pachyonychia congenita affecting nails only: A sporadic case or novel mutation of an uncommon genodermatoses. Int J Health Allied Sci [serial online] 2017 [cited 2020 Feb 17 ];6:191-193
Available from: http://www.ijhas.in/text.asp?2017/6/3/191/212588


Full Text



 Introduction



Pachyonychia congenita (PC) is a rare genodermatoses having autosomal dominant pattern of inheritance.[1] PC is characterized by hypertrophic nail changes and nail dystrophy and is usually present at birth or develop within 1 year of birth. Apart from the nail changes, PC is also associated with oral mucosa, skin, hair, and teeth involvement. Muller and Wilson described the first case of PC, and then after a year, same condition was reported by Jadassohn–Lewandowsky.[1],[2],[3] On the basis of clinical features found in addition to the nail changes, PC has been classified into four types. Herein, we report a rare case of PC Type 1 affecting the nails only with no family history or other syndrome abnormality.

 Case Report



A 26-year-old female presented with disfigured nails of both hands and both feet involving all 20 digits since birth. She had occasional painful swelling and shedding of nails.

She also complained of hyperhidrosis of palms and soles. The patient is born to consanguineous parents and has siblings with no similar complaints in the family tree unto previous two generations. The patient is married and has two children aged 4 years and 1-month-old and have no abnormalities [Figure 1]. Antenatal, natal, and postnatal history were unremarkable. Initially, parents noticed few thickened nails of fingers and toes at birth and gradually involved all the twenty nails. On examination, discoloration of the nails which are lustreless, thickening of the nails with uplifting, and tenting of the distal nails are noted. The nails also show presence of a great amount of subungual hyperkeratosis and adhesion of the nail plate to the underlying nail bed [Figure 2]. There was hypercurvature of the transverse axis of all nail plates giving a “pinched shape” or “door wedge shape” to the free edge of the nail plate [Figure 3]. No other skin lesions were noted with palms, soles, and mucous membrane examination being normal [Figure 4]. There were no other ectodermal abnormalities, and systemic examination was normal. The routine investigations were within the normal limits. Potassium hydroxide examination of the nails did not reveal any fungi. Patient's hair, teeth, throat, and ophthalmological examination were normal. These clinical features with characteristic nail changes were diagnosed as PC Type 1 (Jadassohn–Lewandowsky syndrome) affecting only nails with no family history and other syndrome abnormalities, which is a rare presentation of an uncommon genodermatoses.{Figure 1}{Figure 2}{Figure 3}{Figure 4}

The patient was counseled about the cosmetic disfigurement and debilitating nature of the disease. Paring of the nails was done, and topical keratolytics were advised for symptomatic relief. She was told to report back for follow-up after completion of breast feeding of her child for starting her on systemic retinoids.

 Discussion



PC is a rare group of inherited ectodermal dysplasias transmitted in an autosomal dominant fashion. It may occur as a sporadic case with spontaneous mutation. Four variants of PC have been identified:[1],[2],[3]

PC Type 1 (Jadassohn–Lewandowsky syndrome) characterized by focal palmoplantar keratoderma and follicular keratotic papules over bodyPC Type 2 (Murray–Jackson–Lawler syndrome) having natal teeth and steatocystoma multiplex along with features of PC type 1PC Type 3 (Schafer–Branauer syndrome) includes combined features of Types 1 and 2 with angular cheilitis, corneal dyskeratosis, and cataractsPC Type 4 includes features of Types 1–3 with laryngeal lesions, hoarseness of voice with mental retardation, hair abnormalities, and alopecia.

Jadassohn–Lewandowsky syndrome represents a group of rare, autosomal dominant keratin disorders with characteristic nail findings and with the additional abnormalities of the palmoplantar skin, pilosebaceous apparatus, oral and laryngeal mucosae, teeth, and hair.[4]

This syndrome results from mutations in genes encoding epidermal keratinocyte keratins, specifically the 1A and 1B helical encasing regions of keratins. K6a, K6b, K16, and K17 are the most frequent sites of mutations. The mutation is likely to have a deleterious effect on protein structure as it interferes with the assembly of polypeptides forming the keratin skeleton of epidermal cells.[5],[6],[7] The hallmark of this syndrome is hyperkeratosis of the nail bed. This type of subungual hyperkeratosis leads to the elevation and increased transverse curvature of the nail plate. The elevation is most pronounced distally resulting in an omega or pincer nail deformity. The nail plates are also discolored, thick, and friable, and they sometimes fail to reach the distal fingertip. In general, all the twenty nails are involved, although the findings are often most severe on thumbs, index fingers, and toes.[5],[8]

The age of onset of the various manifestations is variable, but dystrophy of the nails usually presents within the 1st month of life.[8] However, many cases have been described with the onset of characteristic nail changes during the second or the third decade of life along with palmoplantar keratoderma, hyperhidrosis, and oral leukokeratosis. Such cases could be interpreted as PC tarda or late-onset PC, a term suggested by Paller et al.[9] Isolated early-onset nail change is very rare, and late-onset isolated nail dystrophy is even more unusual.[9],[10],[11],[12],[13] The treatment is usually unsatisfactory and the options include topical application of salicylic acid, urea, and 5-fluorouracil. The other treatment options are systemic therapy such as oral retinoids (acitretin, retinoic acid) and surgery.[14],[15]

Our case thus represents a rare presentation of PC with only nail involvement. The possible explanation for only nail involvement could be either a sporadic case, novel or incomplete mutation, as there is no family history in our case. Hence, further genetic studies are warranted to delineate the exact cause. This case has been reported because of its rarity and due to the cosmetic disfigurement and debilitating nature of this condition. The treatment is aimed at reducing disability and morbidity and to alleviate symptoms, as conventional treatments are usually resistant or unsatisfactory. The use of small interfering RNAs (siRNA) to regulate keratin expression is being explored,[16] and PC seizes to be one of the rare genodermatoses where numerous research and clinical trials are yet to translate into a successful outcome.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Judge MR, McLean WH, Munro CS. Disorders of keratinization. In: Burns T, Breathnach S, Cox N, Griffiths C, editors. Rook's Textbook of Dermatology. 7th ed. Oxford: Blackwell Science Ltd.; 2004. p. 34.1-34.111.
2de Berker DA, Baran R, Dawber RP. Disorder of nails. In: Burns T, Breathnach S, Cox N, Griffiths C, editors. Rook's Textbook of Dermatology. 7th ed. Oxford: Blackwell Science Ltd.; 2004. p. 62.1-62.62.
3Feinstein A, Friedman J, Schewach-Millet M. Pachyonychia congenita. J Am Acad Dermatol 1988;19:705-11.
4Dahl PR, Daoud MS, Su WP. Jadassohn-lewandowski syndrome (pachyonychia congenita). Semin Dermatol 1995;14:129-34.
5Su WP, Chun SI, Hammond DE, Gordon H. Pachyonychia congenita: A clinical study of 12 cases and review of the literature. Pediatr Dermatol 1990;7:33-8.
6Smith FJ, Liao H, Cassidy AJ, Stewart A, Hamill KJ, Wood P, et al. The genetic basis of pachyonychia congenita. J Investig Dermatol Symp Proc 2005;10:21-30.
7Liao H, Sayers JM, Wilson NJ, Irvine AD, Mellerio JE, Baselga E, et al. A spectrum of mutations in keratins K6a, K16 and K17 causing pachyonychia congenita. J Dermatol Sci 2007;48:199-205.
8Leachman SA, Kaspar RL, Fleckman P, Florell SR, Smith FJ, McLean WH, et al. Clinical and pathological features of pachyonychia congenita. J Investig Dermatol Symp Proc 2005;10:3-17.
9Paller AS, Moore JA, Scher R. Pachyonychia congenita tarda. A late-onset form of pachyonychia congenita. Arch Dermatol 1991;127:701-3.
10Chang A, Lucker GP, van de Kerkhof PC, Steijlen PM. Pachyonychia congenita in the absence of other syndrome abnormalities. J Am Acad Dermatol 1994;30:1017-8.
11Pryce DW, Verbov JL. A family with pachyonychia congenita affecting the nails only. Clin Exp Dermatol 1994;19:521-2.
12Dogra S, Handa S, Jain R. Pachyonychia congenita affecting only the nails. Pediatr Dermatol 2002;19:91-2.
13Nanda S, Grover C, Chaturvedi KU, Garg VK, Reddy BS. Pachyonchia congenita tarda with nail manifestations only. Pediatr Dermatol 2005;22:283-5.
14Thomsen RJ, Zuehlke RL, Beckman BI. Pachyonychia congenita: Surgical management of the nail changes. J Dermatol Surg Oncol 1982;8:24-8.
15Hoting E, Wassilew SW. Systemic retinoid therapy with etretinate in pachyonychia congenita. Hautarzt 1985;36:526-8.
16Smith FJ, Hickerson RP, Sayers JM, Reeves RE, Contag CH, Leake D, et al. Development of therapeutic siRNAs for pachyonychia congenita. J Invest Dermatol 2008;128:50-8.