INTRODUCTION
When a clinician is confronted with a patient with
multiple cutaneous lesions of the same type, the
possibility of extracutaneous involvement and genetic/
syndromic associations must often be investigated. This
review article addresses the cutaneous features of clinical entities
with multiple “copies” of vascular and pigmentary lesions
and the attendant clinic considerations, diagnostic evaluation,
and therapeutic options in these settings.
Vascular Lesions
Hereditary hemorrhagic telangiectasia
Hereditary hemorrhagic telangiectasia (HHT) or Osler-Weber-
Rendu syndrome is an autosomal dominant vascular disorder,
with a prevalence 1:5000.1 In addition to the cutaneous hallmark
of multiple, particularly mucocutaneous telangiectasias,
the condition has multiple extracutaneous manifestations
such as epistaxis and visceral arteriovenous malformations
(pulmonary, cerebral, hepatic). The three most common gene
mutations associated with HHT are in endoglin, ACLVR-1/ALK-
1 and SMAD4 and depending on the mutation, patients may
present primarily with pulmonary A-V fistulas, hepatic arteriovenous
malformations (AVM), or juvenile polyposis.2,3,4 A
positive family history is helpful for diagnosis.
Recurrent and spontaneous epistaxis is usually the first symptom
of HHT, with the average age of onset around 12 years of age and
full penetrance by age 40. Telangiectasias are most commonly
found on the lips, tongue, buccal mucosa, fingers, and subungually,
but may occur anywhere and continue to evolve. Prognosis
depends on visceral, namely cerebral (23% of cases), pulmonary,
and hepatic/GI tract involvement.4 The telangiectasias in HHT need to be distinguished from common telangiectasias and spider angiomas
seen particularly on the face and wrist of children. These
children do not present with extracutaneous findings.
Management of HHT depends on the subtype and may include
screening colonoscopy, referral to ENT for epistaxis, pulse dye
laser for cutaneous lesions and screening MRI and transthoracic
contrast echocardiography to screen for cerebral and pulmonary
involvement, respectively. Hepatic AVM's can be diagnosed with
ultrasound or CT. Positive findings on screening should generally
result in referral to a neurovascular center. If initial screening test
is negative in a high-risk patient, repeat screening after puberty,
before pregnancy, or every 5-10 years. Patients with hepatic VM
and intractable heart failure, portal hypertension, or ischemic
biliary necrosis may require hepatic transplantation.4
Ataxia telangiectasia
Ataxia telangiectasia (AT) is an autosomal recessive neurodegenerative
disorder involving multiple organ systems. AT is
characterized by progressive cerebellar ataxia, oculocutaneous
telangiectasia, humoral and cellular immunodeficiency,
ionizing radiation sensitivity, and lymphoid neoplasms. AT occurs
in approximately 1:30,000 live births. Approximately 1%
of the Caucasian population is a heterozygote carrier for the
AT gene.5 AT is caused by a mutation in the AT mutated gene
(ATM gene). ATM is important in cell cycle progression and
the detection of DNA damage.6
Ataxia as the first symptom usually presents after 12 months of
age when the child begins to walk. Children have difficulty with
posture and tend to wobble or fall to one side.5 They are unable
to control gross and fine motor skills and develop muscle wast-
