Clinicopathologic evaluation of cardiofaciocutaneous syndrome: overcoming the challenges of diagnosing a rare genodermatosis.

We report the case of a 2-year-old boy from a family with limited financial resources who presented with cutaneous abnormalities, a history of congenital heart defect, and a presumptive diagnosis of Noonan syndrome. Genetic testing had been deferred because of a lack of funds. Skin findings were characteristic of cardiofaciocutaneous syndrome, including keratosis pilaris, ichthyosis, sparse eyebrows, and multiple nevi. A biopsy of a perifollicular thick papule with background hyperpigmentation was obtained to further characterize the cutaneous findings. Clinical evaluation allowed rapid, cost-effective, specific diagnosis in this patient with a RASopathy-spectrum genetic disorder who did not have access to genetic testing. This time-honored clinical approach is adequate for providing information important for prognosis, follow-up, and counseling. We will also discuss available resources for genetic testing and specialized care for patients with RASopathies.