LEOPARD Syndrome

At a glance

It is an acronym that stands for Lentigines (multiple), Electrocardiographic conduction abnormalities, Ocular hypertelorism, Pulmonary stenosis, Abnormal genitalia, Retardation of growth, and Deafness (sensorineural). It is a complex congenital dysmorphogenetic disorder characterized by skin lesions (lentigines), severe cardiac anomalies (dysrhythmias, pulmonary valve stenosis), ocular hypertelorism, abnormalities of genitalia, sensorineural deafness, and severe retardation of growth. The second most common defects are ventricular septal hypertrophy and pulmonary (or subpulmonary) valve stenosis. The major perioperative complications are severe arrhythmias and/or cardiac decompensation. The presence of nonobstructive asymmetric anteroseptal hypertrophic cardiomyopathy has been reported.

Synonyms

Cardiocutaneous Syndrome; Cardiocutaneous Lentiginosis Syndrome; Cardiomyopathic Lentiginosis; Centrofacial Lentiginosis; Generalized Lentiginosis; Lentiginosis-Deafness-Cardiopathy Syndrome; Lentiginosis Profusa Syndrome; Moynahan Syndrome; Multiple Lentigines Syndrome; Progressive Cardiomyopathic Lentiginosis.

History

This medical condition was first described by Zeisler and Becker in 1936. It has many similarities to ☞Noonan Syndrome, except in the most striking features, from which its name is derived. The acronym was first used by Gorlin et al in 1969.

Incidence

It is a very rare disorder. The exact incidence has not been established. There are no more than 120 cases reported in the medical literature. It is estimated that males and females are affected equally. The life expectancy is comparable to the general population.

Genetic inheritance

Sporadic mutations and an autosomal inheritance dominant have been suggested for transmission. Single mutant gene with high penetrance and variable expression produces the defects in this syndrome. The LEOPARD Syndrome and Noonan Syndrome have similar genetic mutations as mode of genetic expression. Although 85% of individuals affected with LEOPARD Syndrome present a mutation in the protein-tyrosine phosphatase nonreceptor Type 11 (PTPN11) gene that is located on chromosome 12q24.1. Other missense mutations have been reported as a c.836A>G in exon 7 (Tyr279Cys) of the PTPN11 gene.

Pathophysiology

Mutation in the stem cell pool of the neural crest in embryonic life is regarded as a common cause of cutaneous (producing lentigines), neurologic, cardiac (resulting in cardiomyopathy), and possibly urogenital defects. Metabolism of dihydroxyphenylalanine (DOPA), epinephrine, and norepinephrine is altered which may result in abnormal skin pigmentation.

Diagnosis

Diagnostic criteria included skin lentigines plus two other recognized features or a first-degree relative with lentigines plus three other features in the patient. Histologic examination of the lentigines shows pigment accumulation in the dermis and in the deeper layers of epidermis. There is an increase in melanocytic density owing to corrugation of the dermoepidermal junction.

Clinical aspects

Lentigines (1-2 mm; flat, dark brown-to-black cutaneous lesions) can be present at birth and increase in number until puberty. They are most numerous on the face, ...