What is Schöpf-Schulz-Passarge syndrome?
Schöpf-Schulz-Passarge syndrome (SSPS) is a form of ectodermal dysplasia.
Ectodermal dysplasias are a group of inherited disorders which show similar features of developmental abnormalities in two or more of the following structures: hair, teeth, nails, sweat glands, and other ectodermal-derived structures.
SSPS was first reported in 1971 and subsequently named for the three German dermatologists and geneticists who described the characteristic features in two sisters born of a consanguineous marriage. It is rare with less than 50 cases reported in the literature.
What causes Schöpf-Schulz-Passarge syndrome?
Schöpf-Schulz-Passarge syndrome has been linked to mutations in the WNT10A gene on chromosome 2, which are also observed in odonto-onycho-dermal dysplasia, hypohidrotic ectodermal dysplasia, and isolated hypodontia. There is thought to be some overlap with these conditions, however apocrine hidrocystomas of the eyelids are unique to SSPS. To date, 11 different mutations in the WNT10A gene have been linked to SSPS. The WNT10A gene encodes a protein involved in the development and regulation of ectodermal tissue.
Schöpf-Schulz-Passarge syndrome is an autosomal recessive genetic condition, meaning two faulty copies of the gene (ie, one from each parent) are needed for the condition to occur. However, individuals who are heterozygous with one faulty copy of the WNT10A gene may also show hair, nail, skin, or teeth abnormalities.
What are the clinical features of Schöpf-Schulz-Passarge syndrome?
Cutaneous features of Schöpf-Schulz-Passarge syndrome typically do not present in childhood, starting to appear in the early teenage years and becoming more obvious with age. These can include the following features:
- Multiple eyelid cysts (apocrine hidrocystomas) are the cardinal feature, but often do not appear until middle-age
- Thickening of the skin on the hands and the feet (palmoplantar keratoderma)
- Excessive sweating (hyperhidrosis)
- Sparse hair (hypotrichosis)
- Malformation of the nails (onychodystrophy), such as nail fragility or hypoplastic nails.
Non-cutaneous features of SSPS include:
- Abnormal development of the teeth (hypodontia) — deciduous teeth ('baby' teeth) are abnormal and may fall out early
- Bilateral early senile cataract
- Optic atrophy
- Short-sightedness (myopia).
What are the complications of Schöpf-Schulz-Passarge syndrome?
Complications of SSPS include skin fragility, pain, and cosmetic disfigurement. With age, many of the features of SSPS become more troublesome and eyelid cysts become larger and more numerous. Secondary teeth may be abnormal or never erupt.
The risk of SSPS patients developing cancer is controversial, but there may be an increased risk of benign and malignant skin tumours, including squamous cell carcinoma, basal cell carcinoma, eccrine porocarcinoma, and multiple eccrine syringofibroadenomas. Skin surveillance is therefore essential.
How is Schöpf-Schulz-Passarge syndrome diagnosed?
Early diagnosis is rare because the cardinal feature, eyelid cysts, appear at a mean age of 50 years and are asymptomatic. This results in a mean age of diagnosis at 60 years, despite other clinical features presenting earlier in life. It is primarily a clinical diagnosis that does not require further tests, however genetic testing can be arranged.
What is the differential diagnosis for Schöpf-Schulz-Passarge syndrome?
Differential diagnoses for SSPS include other ectodermal dysplasias, such as:
- Odonto-onycho-dermal dysplasia — autosomal recessive ectodermal dysplasia characterised by severe oligodontia, nail dystrophy, hypotrichosis, erythematous lesions of the face, smooth tongue with reduced fungiform and filiform papillae, and palmoplantar hyperkeratosis with increased sweating, but lacks the characteristic eyelid cysts seen in SSPS
- Hypohidrotic ectodermal dysplasias.
What is the treatment for Schöpf-Schulz-Passarge syndrome?
There is no curative treatment for SSPS. Therapy is aimed at symptom management. Suggested therapies include:
- Electrocautery of apocrine hidrocystomas
- Surgical excision of tumours
- Emollients and potassium permanganate soaks for palmoplantar hyperkeratosis
- Water iontophoresis for hyperhidrosis
- Systemic retinoids (eg, acitretin)
- Regular skin examination to detect malignant and benign skin growths
- Regular dental checks and dental prostheses
- Psychological support as necessary
- Genetic counselling as necessary.
What is the outcome for Schöpf-Schulz-Passarge syndrome?
The life expectancy for patients with SSPS is normal.
With advancing age, many of the features become more troublesome, and apocrine hidrocystomas become larger and more numerous.