Netherton Syndrome

At a glance

Congenital disorder that involves production of abnormal bamboo (brittle) hair (diagnostic marker) and associated with onychodystrophy, cataracts, mental retardation, skin sensitivity to light, and ichthyosis.

Synonyms

Psoriasiform Ichthyosis; Trichothiodystrophy; Ichthyosis Linearis Circumflexa; Trichorrhexis Invaginata; Còmel-Netherton Syndrome.

History

Association between hair shaft bamboo node defects and ichthyosiform erythroderma was described by Albert Touraine, a French dermatologist, and Gabriel Solente, a French physician, in 1937. E. W. Netherton, an American physician, described a young girl with generalized scaly dermatitis in 1958.

Incidence

Very rare, estimated 1:200,000 live births; affects almost only females.

Genetic inheritance

Autosomal recessive mutation of the SPINK5 gene on chromosome 5q32. There is considerable phenotypic variability ranging from the neonatal lethal form to less severe forms which are diagnosed in childhood.

Pathophysiology

The SPINK5 gene encodes for the serine protease inhibitor, LEKTI, that is expressed in epithelial and mucosal surfaces and in the thymus. This serine-protease inhibitor is primarily involved in regulation of hair morphogenesis, defects leading to increased protease activity in the stratum corneum, accelerated degradation of desmoglein-1, and over-desquamation of corneocytes. It has been suggested that Netherton Syndrome is not an ichthyosis characterized by the retention of thick adherent scales, but a disease of over-desquamation causing severe skin permeability barrier dysfunction. Microscopically, the hairs have a squashed oval shape in cross-section and irregular diameter, mostly caused by a reduction in the content of hair sulfur and cysteine. Studies suggest that the protein gene involved in xeroderma pigmentosum group D (XPD) protein gene can lead to trichothiodystrophy.

Diagnosis

Generalized erythroderma and scaling present within the first week following birth.

Clinical aspects

Affected children present with erythroderma within 1 to 6 weeks of birth. Bamboo hair, atopic diathesis, congenital ichthyosiform erythroderma. Hypogammaglobulinemia. May be confused with atopic dermatitis, but does not respond to topical corticosteroid treatment.

Precautions before anesthesia

Evaluate the severity of hypogammaglobulinemia. Ensure that no topical steroids are used (risk of depression of the adrenocortical production of steroids and of perioperative addisonian-like crisis).

Anesthetic considerations

The high risk of infection as a result of immunodeficiency must be considered. Pay special attention to the skin when positioning and securing the intravenous access and monitoring devices and use aseptic precautions. Temperature regulation management is essential intraoperatively. Fluid and electrolyte management must be very intensive because of excessive skin loss. These children may require more perioperative fluids.

Pharmacological implications

No medications are described as harmful. However, it is recommended to avoid thiopentone in the very severe bullous form.