Laryngo-Onycho-Cutaneous (LOC) Syndrome

At a glance

It is a severe progressive multisystem disorder involving the skin (dermal granula and ulcerations) and larynx (vocal cord granuloma). It is often considered a subtype of junctional epidermolysis bullosa (JEB) Syndrome. However, it has a distinct clinical and pathological appearance and molecular fingerprint. It is often lethal during childhood.

Synonyms

Laryngeal and Ocular Granulation in Indian Children; LOGIC Syndrome.

Incidence

The exact incidence remains unknown. There are fewer than 50 cases that have been reported in the literature.

Genetic inheritance

It is presumed inherited as an autosomal recessive trait. This medical condition was reclassified as a subtype of Junctional Epidermolysis Bullosa Syndrome based on clinical features and its association, in the majority of patients from the Punjab, with a unique mutation affecting the N terminus of the alpha3 chain of LM332. However, it has a distinct clinical and pathological appearance and molecular fingerprint.

Pathophysiology

Caused by an inherited defect affecting the lamina lucida of the skin basal membrane layer.

Diagnosis

Demonstration of dermal and submucosal granulation with vocal cord involvement.

Clinical aspects

Onset within 2 weeks of birth; death common in childhood. Hoarse, weak cry, vocal cord granulation, dystrophic changes in the nails, with recurrent loss of toenails and fingernails dermal granuloma, skin ulceration, conjunctival scarring, and amelogenesis imperfecta.

Precautions before anesthesia

Significant risk of airway obstruction because of the presence of a laryngeal web and large supraglottic and glottic nodules; epiglottic and supraglottic edema may be present with ulceration and contact bleeding, together with swollen and poorly defined cords.

Anesthetic considerations

Permanent tracheotomies may be required which may lead to granulation formation and obstruction distally in the trachea.

Pharmacological implications

Determined by degree of airway obstruction.

Other condition to be considered

• Junctional Epidermolysis Bullosa (JEB) Syndrome: Skin condition characterized by blister formation within the lamina lucida of the basement membrane zone. Three types have been described and consist of: (1) Junctional Epidermolysis Bullosa with Pyloric Atresia/Stenosis: It is a rare form of the medical condition associated with pyloric stenosis at birth and severe mucocutaneous fragility; (2) Junctional Epidermolysis Bullosa Gravis (Herlitz Disease, Herlitz Syndrome, Lethal Junctional Epidermolysis Bullosa): It is the most lethal type of epidermolysis bullosa; (3) Junctional Epidermolysis Bullosa Non-Herlitz: It is divided into three subtypes, ie, Generalized atrophic benign epidermolysis bullosa that is characterized by onset at birth, generalized blisters and atrophy, mucosal involvement, and thickened, dystrophic, or absent nails; Mitis junctional epidermolysis bullosa (Nonlethal junctional epidermolysis bullosa) presents clinically between the ages ...