Hypertrichosis is a condition characterized by excessive hair growth in any part of the body or throughout the entire body. This Hormone independent situation can manifest in both congenital and acquired forms. Hypertrichosis must not be confused with hirsutism; while hirsutism develops in androgen-sensitive areas due to hormonal influences, hypertrichosis occurs independently of androgens.
This disease genetic can arise from a wide range of causes, including drug use, metabolic disorders, and paraneoplastic syndromes. Treatment varies depending on the underlying cause, but cosmetic methods are generally among the preferred solutions.
Epidemiology
- Prevalence: Hypertrichosis is a rare condition. Congenital hypertrichosis is particularly uncommon, while acquired hypertrichosis may be more frequent.
- Gender distribution: It can occur in both sexes, but women are more likely to seek medical attention due to cosmetic concerns.
- Age group: Congenital forms typically become apparent at birth, while acquired hypertrichosis can develop at any age.
Etiology and Pathogenesis
Hypertrichosis can develop due to various causes including genetics, medications, metabolic diseases, and certain tumors like.
1. Genetic and Congenital Factors
- Congenital hypertrichosis lanuginosa: Characterized by the failure of lanugo hairs to shed after birth.
- Congenital hypertrichosis terminalis: Defined by the widespread presence of terminal hairs from birth.
- Some genetic syndromes: Hypertrichosis is a prominent feature in conditions such as Ambras syndrome.
2. Drug-Induced Hypertrichosis
Certain medications can cause hypertrichosis. The most common include:
- Minoxidil: A drug that promotes hair growth.
- Cyclosporine: An immunosuppressant used in organ transplantation that can induce hypertrichosis.
- Phenytoin: A medication used in the treatment of epilepsy.
- Steroids and Diazoxide: These drugs, used in some endocrine disorders, may increase hair growth.
3. Metabolic and Endocrine Disorders
Some metabolic conditions can lead to increased hair growth:
- Hypothyroidism: May be associated with increased hair growth along with skin changes.
- Porphyria: A metabolic disorder that may be linked to hypertrichosis.
4. Paraneoplastic Syndromes
- Malignant hypertrichosis lanuginosa: Associated with malignant conditions such as lung, gastrointestinal, or breast cancer. It is characterized by the sudden appearance of fine lanugo hairs over large areas of the body.
5. Trauma and Mechanical Factors
- Increased hair growth may occur in areas exposed to burns or chronic trauma (reactive hypertrichosis).
Clinical Types
Hypertrichosis can be classified as either congenital or acquired.
1. Congenital Hypertrichosis
- Congenital hypertrichosis lanuginosa: Results from the persistence of lanugo hairs, which normally cover the fetal body and are shed before birth.
- Congenital hypertrichosis terminalis: Characterized by the presence of thick, pigmented terminal hairs over the entire body from birth.
2. Acquired Hypertrichosis
- Focal hypertrichosis: Limited increase in hair growth in a specific area, often due to trauma, inflammation, or mechanical stimulation.
- Generalized hypertrichosis: Widespread increase in hair growth over the entire body, associated with metabolic disorders, medications, or paraneoplastic syndromes.
- Malignant hypertrichosis lanuginosa: Characterized by marked increase in lanugo hairs over the entire body and is associated with cancer.
Diagnosis and Differential Diagnosis
Definition is established based on clinical findings and patient history. However, certain laboratory tests and imaging methods may be used to identify the underlying cause.
Diagnostic Methods
- Physical examination: The location, density, and type of hair growth are assessed.
- Hormone tests: Androgen levels are typically normal (unlike in hirsutism).
- Genetic testing: Genetic analysis may be performed in cases of congenital hypertrichosis.
- Imaging studies: If a paraneoplastic syndrome is suspected, cancer screening may be required.
Differential Diagnoses
- Hirsutism: Androgen-dependent increase in hair growth, often associated with endocrine disorders such as polycystic ovary syndrome.
- Lanugo hair growth: May be associated with anorexia nervosa or cancer.
- Drug-induced hypertrichosis: Evaluation of medications taken is essential.
Treatment and Management
The treatment of hypertrichosis depends on identifying the underlying cause. However, for most patients, cosmetic interventions are the most commonly preferred approaches.
1. Medical Treatment
- Discontinuation of medications: If drug-induced hypertrichosis is present, stopping the medication may reduce hair growth.
- Topical eflornithine: Can be used to reduce facial hair growth.
2. Physical and Cosmetic Methods
- Shaving and waxing: Provide temporary solutions.
- Laser epilation: A permanent hair reduction method.
- Electrolysis: A method that provides permanent hair removal, though it is time-consuming.
3. Treatment of Underlying Conditions
- In cases of hypertrichosis associated with metabolic or endocrine disorders, treating the primary disease may resolve the hair growth issue.
- In cases of paraneoplastic hypertrichosis, the underlying cancer must be treated.
