What are the other Names for this Condition? (Also known as/Synonyms)

• Chromosome Xq27.1 Interchromosomal Insertion Syndrome
• Congenital Generalized Hypertrichosis, Macias-Flores type
• Macias-Flores Garcia-Cruz Rivera Syndrome

What is X-Linked Congenital Generalized Hypertrichosis? (Definition/Background Information)

• X-Linked Congenital Generalized Hypertrichosis is an uncommon skin and hair condition that is inherited in an X-linked dominant manner. This means that the condition is predominantly noted in males
• The condition is characterized by abnormal hair growth, distinctive facial features, and hearing impairment. In some cases, X-Linked Congenital Generalized Hypertrichosis develops as part of other genetic disorders
• The management of X-Linked Congenital Generalized Hypertrichosis includes hair removal through repeated shaving, use of topical agents, electrolysis, waxing, or laser therapy. The other presentations may be resolved via symptomatic treatment. The overall outcomes are generally good

Who gets X-Linked Congenital Generalized Hypertrichosis? (Age and Sex Distribution)

• X-Linked Congenital Generalized Hypertrichosis is a rare congenital disorder. The presentation of symptoms may occur at or following the birth of the child
• The disorder predominantly affects males, although some females carrying the defective X chromosome may show mild symptoms
• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for X-Linked Congenital Generalized Hypertrichosis? (Predisposing Factors)

• A positive family history may be an important risk factor, since X-Linked Congenital Generalized Hypertrichosis can be inherited
• No other specific risk factors have been currently recognized for the disorder

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of X-Linked Congenital Generalized Hypertrichosis? (Etiology)

• X-Linked Congenital Generalized Hypertrichosis is caused by changes or mutations in the long arm of the X chromosome
• The disorder is inherited in an X-linked dominant manner

X-linked dominant inheritance pattern: In this type of inheritance, the defective gene is carried on the X chromosome. A single copy of the defective gene in each cell of an individual is sufficient for the disease to manifest itself. Since males have only one X chromosome inherited from their mother, the defective gene is expressed in them, causing the condition. Although females carry two X chromosomes, the unaffected gene copy in the normal X chromosome does not completely mask the effects of a defective gene copy.

What are the Signs and Symptoms of X-Linked Congenital Generalized Hypertrichosis?

The signs and symptoms of X-Linked Congenital Generalized Hypertrichosis are more pronounced in males, and milder in females. The signs and symptoms may include:

• Presence of excessive hair growth on the entire body in males
• In females, the hair overgrowth is much milder and may be observed irregularly on the body
• Abnormal facial features may include:
  • Upward tipped nasal openings
  • Mild to moderate jaw protrusion
• Hearing impairment
• Dental (teeth) anomalies that is observed rarely

How is X-Linked Congenital Generalized Hypertrichosis Diagnosed?

X-Linked Congenital Generalized Hypertrichosis is diagnosed on the basis of the following information:

• Complete physical examination with evaluation of family medical history
• Dermoscopy: It is a diagnostic tool where a dermatologist examines the skin using a special magnified lens
• Wood’s lamp examination: In this procedure, the healthcare provider examines the skin using ultraviolet light. It is performed to examine the change in skin pigmentation
• Skin biopsy: A skin biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis
• Molecular genetic testing to check for or confirm specific causative gene mutation(s)
• Prenatal testing in pregnant women

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of X-Linked Congenital Generalized Hypertrichosis?

The complications of X-Linked Congenital Generalized Hypertrichosis may include:

• Severe emotional stress including social isolation
• Abnormal spinal curvature (scoliosis)
• Back pain due to scoliosis
• Crowding in the chest cavity from scoliosis, leading to heart and lung abnormalities
• Deafness
• Low self-esteem because one’s appearance
• Hearing loss

Complications may occur with or without treatment, and in some cases, due to treatment also.

How is X-Linked Congenital Generalized Hypertrichosis Treated?

There is no cure for X-Linked Congenital Generalized Hypertrichosis since it is a genetic condition. The treatment is usually given to manage the signs and symptoms and any complication that develops. The treatment measures may include:

• Excess or unwanted hair may be removed by suitable hair removal methods such as:
  • Use of topical creams
  • Waxing
  • Laser hair removal
  • Electrolysis
  • Chemical hair removal
• Scoliosis may require a brace to limit curvature in growing children. In severe cases, surgery may be necessary to correct the abnormality
• Dental procedures may be required to correct teeth abnormalities

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

How can X-Linked Congenital Generalized Hypertrichosis be Prevented?

Currently, X-Linked Congenital Generalized Hypertrichosis may not be preventable since it is a genetic disorder.

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

What is the Prognosis of X-Linked Congenital Generalized Hypertrichosis? (Outcomes/Resolutions)

• The prognosis of X-Linked Congenital Generalized Hypertrichosis is dependent upon the severity of the signs and symptoms and associated complications, if any. The prognosis may vary from one individual to another
• In most cases, the disorder is known to be mild and can be adequately managed through suitable treatment measures. The outcomes for most children (boys) are generally favorable

Additional and Relevant Useful Information for X-Linked Congenital Generalized Hypertrichosis:

The following DoveMed website link is a useful resource for additional information:

https://www.dovemed.com/healthy-living/skin-disorders/