Hidradenitis Suppurativa

What is hidradenitis suppurativa (HS)?

From: MedlinePlus, National Library of Medicine

Hidradenitis suppurativa (HS) is a chronic skin disease. Another name for it is acne inversa. It causes painful, boil-like lumps that form under the skin. It often affects areas where the skin rubs together, such as your armpits and groin. The lumps become inflamed and painful. They often break open, causing abscesses that drain fluid and pus. As the abscesses heal, they can cause scarring of the skin.

What causes hidradenitis suppurativa (HS)?

From: MedlinePlus, National Library of Medicine

The lumps in HS form because of blockages of the hair follicles. The blocked hair follicles trap bacteria, which leads to inflammation and rupture. In most cases, the cause of the blockages is unknown. Genetics, environment, and hormonal factors may play a role.

HS is not caused by bad hygiene, and it cannot be spread to others.

Who is more likely to get hidradenitis suppurativa (HS)?

From: MedlinePlus, National Library of Medicine

HS typically starts after puberty, usually in the teens or twenties. It is more common in:

• Women
• People who are Black
• People with a family history of HS
• People who are overweight or have obesity
• People who smoke

What are the symptoms of hidradenitis suppurativa (HS)?

From: MedlinePlus, National Library of Medicine

The symptoms of HS include:

Symptoms of HS can range from mild to severe. They can include:

Because of the difficulty of dealing with the disease, people with HS are at risk for depression and anxiety.

• Small pitted areas of skin containing blackheads.
• Painful, red, lumps that get bigger and break open. This causes abscesses that drain fluid and pus. They may itch and have an unpleasant odor.
• The abscesses heal very slowly, come back over time, and can lead to scarring and tunnels under the skin.
• Only one or a few lumps in one area of the skin.
• Lumps that keep coming back, get bigger, and break open. The lumps form in more than one area of the body.
• Lumps that are widespread, along with scarring, and chronic (long-term) pain that may make it hard to move.

How is hidradenitis suppurativa (HS) diagnosed?

From: MedlinePlus, National Library of Medicine

There is no specific test for HS. It can be hard to diagnose in the early stages because it can look like pimples or acne. To find out if you have HS, your health care provider:

• Will ask about your medical history and your symptoms
• Will look at the lumps on your skin
• May take a sample of the skin or pus (if there is any) and send it to a lab for testing

Your provider may refer you to a dermatologist (a doctor who specializes in skin disorders) to get a diagnosis or treatment.

What are the treatments for hidradenitis suppurativa?

From: MedlinePlus, National Library of Medicine

Treatments focus on the symptoms, but they are not always effective for everyone. The treatments depend on how severe the disease is and may include:

It may also help if you can avoid things that can irritate your skin, by:

• Medicines, including steroids, antibiotics, pain relievers, hormone pills, and medicines that fight inflammation. In mild cases, the medicines may be topical (applied to your skin), injected or taken orally (by mouth).
• Biologics, which are a type of medicine made from living sources, such as cells, tissues, and proteins.
• Procedures or surgery to remove the lumps and scars or make the sores go away.
• Laser hair removal may be helpful in the early stages of HS.
• Wearing loose-fitting clothing
• Staying at a healthy weight
• Quitting smoking
• Avoiding heat and humidity
• Being careful not to injure your skin

Genetic causes described in the linked summary

From: MedlinePlus Genetics

In most cases, the cause of hidradenitis suppurativa is unknown. The condition probably results from a combination of genetic and environmental factors. Originally, researchers believed that the disorder was caused by the blockage (occlusion) of specialized sweat glands called apocrine glands. However, recent studies have shown that the condition actually begins with a blockage of hair follicles in areas of the body that also contain a high concentration of apocrine glands (such as the armpits and groin). The hair follicles have a buildup of a fibrous protein called keratin (hyperkeratosis). The blocked hair follicles trap bacteria, leading to inflammation and rupture. Researchers have several ideas about what initially causes the follicles to become blocked and why the nodules tend to recur, but the causes remain unclear.

Genetic factors clearly play a role in causing hidradenitis suppurativa. Some cases have been found to result from variants (also known as mutations) in the NCSTN, PSEN1, or PSENEN gene. The proteins produced from these genes are all components of a complex called gamma- (γ-) secretase. This complex cuts apart (cleaves) many different proteins, which is an important step in several chemical signaling pathways. One of these pathways, known as Notch signaling, is essential for the normal growth and maturation (differentiation) of hair follicle cells and other types of skin cells. Notch signaling is also involved in normal immune system function. Studies suggest that variants in the NCSTN, PSEN1, or PSENEN gene impair Notch signaling in hair follicles. Although little is known about the mechanism, abnormal Notch signaling appears to promote the development of nodules and lead to inflammation in the skin. Researchers are working to determine whether additional genes, particularly those that provide instructions for making other γ-secretase components, are also associated with hidradenitis suppurativa.

Researchers have studied many other possible risk factors for hidradenitis suppurativa. Obesity and smoking both appear to increase the risk of the disorder, and obesity is also associated with increased severity of signs and symptoms in affected individuals. Studies suggest that neither abnormal immune system function nor hormonal factors play a key role in causing the disease. Other factors that were mistakenly thought to be associated with this condition include poor hygiene, the use of underarm deodorants and antiperspirants, and shaving or the use of depilatory products to remove hair.

Inheritance described in the linked summary

From: MedlinePlus Genetics

Hidradenitis suppurativa has been reported to run in families. Studies have found that 30 to 40 percent of affected individuals have at least one family member with the disorder. However, this finding may be an underestimate because affected individuals do not always tell their family members that they have the condition, and hidradenitis suppurativa is sometimes misdiagnosed as other skin disorders.

In some families, including those with an NCSTN, PSEN1, or PSENEN gene variant, hidradenitis suppurativa appears to have an autosomal dominant pattern of inheritance. Autosomal dominant inheritance means one copy of an altered gene in each cell is sufficient to cause the disorder. In many cases, an affected person inherits the altered gene from a parent who has the condition.

Which doctor should you see?

The suggested department for discussing Hidradenitis Suppurativa is Dermatology, with a dermatologist as the relevant type of clinician. Dermatologist; paediatric services for children as appropriate.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which features of the skin, hair or nails distinguish the possibilities?
• Would photographs over time help document the changes?
• What should be expected from treatment, and how will irritation or other adverse effects be managed?

Treatment discussions and follow-up

Where the source describes treatments, these are an overview of possible care, not a prescription for an individual. Ask which option applies to the confirmed diagnosis, what benefit is expected, what adverse effects to watch for and how progress will be assessed. Availability, approvals and local practice can differ from the country described in the source.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.