Connective tissue nevus

Connective Tissue Nevus

A clinical image of a connective tissue nevus on the skin.

A connective tissue nevus is a type of hamartoma that arises from the connective tissue of the skin. These lesions are characterized by an overgrowth of one or more components of the dermal connective tissue, such as collagen, elastin, or glycosaminoglycans.

Classification

Connective tissue nevi can be classified based on the predominant type of connective tissue involved:

• Collagenous nevi: These are the most common type and are characterized by an excess of collagen fibers. They are often referred to as "shagreen patches" when associated with tuberous sclerosis.

• Elastin nevi: These nevi show an increase in elastin fibers and are sometimes associated with conditions like pseudoxanthoma elasticum.

• Proteoglycan nevi: These are less common and involve an increase in proteoglycans within the dermis.

Clinical Presentation

Connective tissue nevi typically present as firm, skin-colored or yellowish plaques or nodules. They can appear anywhere on the body but are most commonly found on the trunk and extremities. The lesions are usually asymptomatic but may be associated with other systemic conditions.

Associated Conditions

Connective tissue nevi can occur as isolated lesions or as part of a syndrome. Some of the syndromes associated with connective tissue nevi include:

• Tuberous sclerosis: Characterized by the presence of shagreen patches, which are collagenous nevi.
• Buschke-Ollendorff syndrome: A rare genetic disorder characterized by the presence of elastin nevi and osteopoikilosis.
• Proteus syndrome: A complex disorder that can include connective tissue nevi among its many manifestations.

Diagnosis

The diagnosis of a connective tissue nevus is primarily clinical, based on the appearance of the lesions. A skin biopsy can be performed to confirm the diagnosis and to determine the predominant type of connective tissue involved.

Treatment

Treatment is usually not necessary for isolated connective tissue nevi unless they cause cosmetic concerns or discomfort. In such cases, surgical excision or laser therapy may be considered.

Related Pages

• Hamartoma
• Tuberous sclerosis
• Pseudoxanthoma elasticum
• Proteus syndrome