An Overview of Hermansky-Pudlak Syndrome

Hermansky-Pudlak syndrome is a rare genetic condition that causes abnormally light pigmentation of the skin, hair, and eyes (oculocutaneous albinism).

People with the condition may also have bleeding disorders, conditions affecting the lungs and digestive system, and are at increased risk of damage from sun exposure.

There are nine types of Hermansky-Pudlak syndrome. Each type varies in severity and can be associated with other medical conditions.

Prenatal genetic testing can often diagnose Hermansky-Pudlak syndrome. Early diagnosis is ideal to ensure the condition is properly treated, as well as to avoid potentially serious medical complications.

Symptoms

The characteristic appearance of Hermansky-Pudlak syndrome is abnormally light skin, hair, and eyes (also known as partial albinism).

However, two symptoms distinguish Hermansky-Pudlak syndrome from oculocutaneous albinism: platelet dysfunction and bleeding disorders.

80-99% of individuals with the condition have symptoms that can lead to medical complications. Potential health issues include:

• Low white blood cell count and decreased immune function. Having an impaired immune system makes an individual more susceptible to illness and injury and makes it harder for them to recover.
• Excessive bleeding and/or bruising. People with Hermansky-Pudlak syndrome can experience excessive and heavy menstrual flow.
• Vision problems. People may not see well or have abnormal movements of the eyes that affect their vision.

Symptoms of Hermansky-Pudlak syndrome that specifically affect vision include:

• Crossed eyes (strabismus)
• Nearsightedness (myopia)
• Lack of pigmentation in the eyes (ocular albinism)
• Extreme sensitivity to light (photophobia)

People with certain types of Hermansky-Pudlak syndrome may develop scarring in the tissue of their lungs (pulmonary fibrosis). The damage leads to shortness of breath and can have serious medical consequences if left untreated.

Some types of Hermansky-Pudlack syndrome cause cells to accumulate a waxy substance called ceriod, which may increase a person's risk of kidney disease, inflammatory bowel disease, and skin cancer.

Causes

While the condition is generally uncommon, specific types are frequently seen in certain populations. For example, types 1 and 3 are more common in Puerto Rico, where the incidence is approximately 1 in 1,800.

Hermansky-Pudlak syndrome is inherited in an autosomal recessive manner. A person can have a copy of the mutated gene without having symptoms of the condition. If they carry the gene, they could pass it on to a child.

If two people who carry a copy of the affected gene have a child together, the child will develop Hermansky-Pudlak syndrome if they inherit two copies of the mutated gene (one from each parent).

The gene mutations occur in cells that form proteins. These proteins are partially responsible for producing pigment, blood clotting cells, and lung cells. Deficiencies in these proteins can cause low blood counts, abnormal pigmentation, and scarring of lung tissue.

There are at least 10 genes associated with Hermansky-Pudlak syndrome, but changes in the HPS1 gene account for about 75% of cases.

While uncommon, people can develop Hermansky-Pudlak syndrome without having a genetic mutation known to be associated with the condition. In these individuals, the cause is unknown.

Diagnosis

A thorough medical and family history, physical exam, and laboratory tests can be used to diagnose Hermansky-Pudlak syndrome. Using a microscope to analyze pigmentation changes and blood cells can help confirm the diagnosis.

Before and during pregnancy, Hermansky-Pudlak syndrome can also be identified through genetic testing.

A couple can be tested before trying to conceive to find out if they carry genes associated with the condition, which could be passed on to a child.

Prenatal tests can be used to determine if the fetus has inherited the genes. After birth and throughout life, genetic testing can be used to confirm the diagnosis if someone has symptoms of Hermansky-Pudlak syndrome.

Treatment

Many of the direct symptoms of Hermansky-Pudlak syndrome (such issues with vision) can be effectively managed with therapies and compensatory strategies.

However, some of the possible medical consequences of the condition can be life-threatening if left untreated. Therefore, treatment for Hermansky-Pudlak syndrome primarily addresses the medical consequences of the condition.

Doctors who specialize in treating eye conditions (ophthalmologist) can address the vision needs of people with Hermansky-Pudlak syndrome.

If someone is prone to excessive bleeding, bruising, or fluctuating blood counts as a result of the condition, blood transfusions may be necessary. Heavy menstrual periods can sometimes be effectively managed with birth control medication.

Skin issues are common in people with Hermansky-Pudlak syndrome, and they are also at an increased risk for skin cancer. Dermatologists can provide screenings, treatments, and guidance on skin protection.

Individuals with Hermansky-Pudlak syndrome who develop severe pulmonary fibrosis may require a lung transplant. Respiratory and pulmonary medicine specialists can provide guidance about treatment.

Digestive disorders, such as granulomatous colitis, have been observed to co-occur with Hermansky-Pudlak syndrome. Gastroenterologists and dieticians can help manage symptoms and prevent complications, such as bleeding.

While the medical community has made strides in early diagnosis and treatment of Hermansky-Pudlak syndrome, rare conditions remain challenging to manage.

Early intervention and access to resources play an integral role in ensuring people with Hermansky-Pudlak syndrome receive the care and support they need.

Coping

Symptoms like vision problems and a unique physical appearance can be difficult for people with Hermansky-Pudlak syndrome to cope with.

Mental health care, such as therapy and support groups, can help people work through the emotional aspects of living with Hermansky-Pudlak syndrome and develop coping strategies.

A Word From Verywell

Early diagnosis is essential to managing rare genetic conditions like Hermansky-Pudlak syndrome, as well as preventing medical complications.

Doctors, therapists, genetic counselors, and other medical professionals can help people with Hermansky-Pudlak syndrome learn to cope with the condition through individualized treatment that addresses the physical and emotional aspects of life with the condition.

Individuals and families of children with Hermansky-Pudlak syndrome may also benefit from joining support groups where they can discuss the experience of living with the condition, as well as access resources and advocacy.