Types of Acne: Differences, Pictures, Treatments and Prevention

• There are five main types of acne which are categorized according to severity
• These lesions are symptoms of either inflammatory or noninflammatory acne 
• Treatment depends on the type of acne and its severity, with some forms requiring professional treatment

Acne is a chronic skin disease that develops due to excess sebum (oil), dead skin cells and debris becoming trapped within pores. From mildest to most severe, there are several types of acne: blackheads and whiteheads, papules, pustules, cysts and nodules. 

Acne typically develops on the face, shoulders, chest and upper back as these are the areas where oil-producing sebaceous glands are most concentrated.

What Is Acne?

Acne vulgaris is the most prevalent chronic skin disease in the United States, primarily affecting adolescents, but young adults as well. 

Pores contain sebaceous glands that produce and secrete oils to lubricate and protect skin. Symptoms develop when hair follicles (pores) become clogged with oil, dead skin cells and other debris. This matter becomes trapped and hardens, forming a plug called a comedo which is either a whitehead or blackhead.  

When Cutibacterium acnes bacteria propagates, a comedo will develop into inflammatory acne which causes swelling, redness and pus-filled lesions.   

Acne is a multifactorial disease and is linked to hormonal fluctuations, genetics, diet and stress. 

Types of Acne

All acne begins with clogged pores. How acne develops differs from one person to another based on genetics and environmental influences.   

In order of severity, the five main manifestations of acne are comedones, papules, pustules, cysts and nodules. Each differs in appearance, progression and required treatment. 

Comedones

Comedones are the most common type of acne and develop when a pore becomes clogged by oil, grime and dead skin cells. This is the mildest form of acne as it is noninflammatory due to the absence of bacteria. 

Whiteheads

Whiteheads (closed comedones) are hard plugs that have a thin layer of skin over top which seals them from the air; these are white or flesh-colored. Whiteheads are easily identifiable as they are small and firm and are not associated with any swelling or pain.

Blackheads

Blackheads (open comedones) are plugs that are exposed to air which causes them to oxidize and blacken. They develop just beneath the skin’s surface to create a slightly bumpy appearance and rough texture. 

As with whiteheads, blackheads are not associated with bacteria or inflammation.  

Inflammatory acne

Comedonal acne can deteriorate to inflammatory acne when trapped bacteria proliferate within blocked pores. As the bacteria multiply, they break down the walls of hair follicles and spread, triggering a response from the body’s immune system. 

This response causes symptoms to worsen with the formation of pus-filled lesions, and redness and swelling. These lesions will vary in intensity and type depending on the body’s response. 

Pus is made up of infected fluid and dead white blood cells. Inflamed lesions should never be picked at or squeezed as this can spread the bacteria and also cause scarring.

Papules

Papules are the first signs of inflammatory acne. They are very small, solid red bumps that may feel tender and cause irritation; they do not contain pus. When lesion counts are high, skin can feel rough.

Pustules

Pustules look much like blisters and represent mild-to-moderate inflammatory acne. These lesions contain pus—which can be seen at the tip of the lesion—and are surrounded by a red ring of inflammation. They can be painful and tender to the touch.

Cysts

Cysts are large, pus-filled lesions that are red and painful. These lesions form deep beneath the skin’s surface and contain sebum, dead skin cells, debris and C. acnes bacteria. On the surface of the skin, they appear as large boils.  

Cystic acne is a difficult to treat and serious form of acne; lesions can become quite large and cause great discomfort and emotional stress. They can also result in extensive scarring.

Cystic acne requires professional intervention due to its severity.

Nodules

Nodular acne presents with inflammation, cysts and large nodules which form deep within skin tissue and can be seen as bumps on the skin’s surface. Unlike cysts, they are a solid mass and firm to the touch; they do not release pus. 

These bumps can be skin toned but can develop redness as the infection progresses. Nodular acne is severe, painful and can cause extensive tissue damage and scarring; treatment is required from a dermatologist.

Acne Severity

The severity of acne can vary markedly from a few minor blemishes to severely inflamed lesions. When assessing severity, it’s not only the type but the number of lesions; it can also present as one type or be a combination of many.  

While there are many acne assessment methods, they use different variables to classify acne severity, and currently there is no universally accepted system.

One well-known and reliable method is the Global Acne Grading System (GAGS) which gives a weight to five areas of the face as well as the back. Each region is given a score based on the type and number of lesions. The total score then provides the final grade. 

For example: 

• No lesion = 0 
• One comedone = 1
• One papule = 2,
• One pustule = 3
• One nodule = 4

The severity is graded as:

• Mild, if the score is 1–18 
• Moderate, with scores of 19–30 
• Severe, with scores of 31–38
• Very severe, if the score is more than 38 

The Dermatology Life Quality Index (DLQI)  is another valuable tool that is typically used alongside these grading systems to determine the impact on quality of life for acne patients. This is a 10-item self-assessment questionnaire; the higher the score the greater the impact.  

Other forms of acne

There are several other forms of acne that have been identified, including acne conglobata which is rare and acne mechanica which can affect anyone.  

Acne conglobata

Acne conglobata is a severe form of acne consisting of deep-seated abscesses that interconnect beneath the skin. These abscesses contain a foul-smelling pus that is discharged on the skin’s surface and develops on the arms, chest, buttocks and neck.

This form of acne can cause severe damage to tissue that can result in disfiguring scars. As such, it is vital to seek professional care as soon as possible in order to control symptoms and minimize damage.

Acne mechanica

Acne mechanica occurs when skin is subjected to pressure, heat and friction. This can result from wearing sports gear such as baseball hats, helmets, shin guards or other protective equipment. It can also be triggered by tight-fitting clothes, straps and belts. 

This acne develops due to oils, dead skin cells and bacteria becoming trapped in a humid environment which encourages acne breakouts. The lesions that develop can take the form of whiteheads and blackheads or papules and pustules.

Acne Treatments

Acne treatments consist of topical applications as well as systemic forms of therapy, and are based on severity; often both are used simultaneously to achieve best results. 

Topical treatments

Over-the-counter (OTC) creams and ointments with salicylic acid are very effective against comedonal acne as they have strong exfoliative benefits to clear pores and prevent pore buildup. 

This agent can also benefit inflammatory acne. One study comparing various agents demonstrating that a treatment combining benzoyl peroxide and salicylic acid produced the best results for both comedonal and inflammatory acne symptoms. This can be attributed to benzoyl peroxide’s ability to kill acne-causing bacteria.   

Prescription topicals such as retinol are considered for acne of any severity as well as for maintenance therapy. Antibiotics are typically prescribed for moderate to severe and treatment-resistant acne; these are used for a specific period of time. 

Topical treatments are also prescribed in combination and in conjunction with oral acne treatments for a tailored acne regimen. 

Systemic treatments 

Oral antibiotics such as tetracycline, doxycycline and erythromycin kill C. acnes to reduce redness, inflammation and discomfort. Due to their potential side effects and antimicrobial resistance, these treatments are typically reserved for moderate or severe acne.

Oral contraceptives are usually limited to women with severe or treatment-resistant acne, for those with monthly flare-ups and when conventional therapies are not appropriate. These work by stabilizing hormone levels which in turn reduces excess sebum production  

Isotretinoin is another oral treatment used for severe acne symptoms and for people who have not responded to other established treatments. While on this therapy, patients must be monitored as there are a number of associated side effects.

For nodular acne, oral retinoids are first-line therapy for severe and difficult-to-treat cases. For those unable to tolerate retinoids, antibacterials and benzoyl peroxide are used in combination therapy. Other options include oral contraceptives for women and topical retinoids. 

Lastly, corticosteroid injections are also indicated for very severe cases of nodular acne and are injected directly into nodules to control symptoms and reduce inflammation and pain.

Professional Treatments 

In some cases, acne may require in-office treatments alongside oral and topical interventions.  These include laser therapy, light therapy and chemical peels, depending on the type and severity of the acne. 

Cysts and nodules may require drainage and extraction when other treatment options fail. During these procedures, a dermatologist makes a surgical incision in the affected area to drain fluids and pus from the cyst or nodule. 

Takeaway

Acne is a very common skin disease that is characterized by mild comedonal acne or moderate to severe inflammatory symptoms. 

Treatment should be started immediately to control symptoms, heal lesions and prevent new breakouts from developing. Your treatment will depend on what type of acne you have and whether it’s mild, moderate or severe. 

Mild forms of acne can be effectively treated with OTC skin care ointments and creams that are formulated with active ingredients such as benzoyl peroxide and salicylic acid to kill bacteria and exfoliate and clear pores.

Moderate to severe acne typically requires prescription-strength topicals such as retinol; and oral antibiotics such as tetracycline, doxycycline and erythromycin to kill bacteria and ease inflammation. Severe nodular acne is treated with a number of medications including  antibacterials and corticosteroid injections. 

Depending on the severity and individual response, your dermatologist may use a combination of several treatments as well as professional procedures for the best outcome.

See your dermatologist to understand your specific acne symptoms and to discuss your treatment options. It is especially important to do so if you have any signs of severe acne to manage your symptoms and minimize scarring.