Acne is a skin disorder which turns up in many forms. Acne lesions crop up mostly on the face, upper back, neck, and chest. On the basis of severity, we mainly experience three major types of acne lesions:
II. Noninflammatory acne lesions
III. Inflammatory acne lesions
First and smallest appearance of acne is called microcomedo. This type of lesion forms at the earliest stage when the hair follicle walls start to swell up due to clogged pores. These are microscopic in size. If allowed to develop further, microcomedo leads to shape noninflammatory or inflammatory lesion.
II. Noninflammatory Acne Lesions
Microcomedones often accrue to appear as noninflammatory lesions. These types of acne lesions consist of blackheads (open comedones) and whiteheads (closed comedones)
• Blackhead: Blackheads or open comedones grow up owing to the enlargement and amplification of clogged pores, which arise due to the accumulation of flakes and dead cells of skin into hair follicles. In these cases pores remain partially open, allowing slow drainage of trapped sebum (oil secreted by sebaceous gland) and dead skin cells. Blackheads emerge as black plugs at hair follicle pores. However, dirt particles do not cause the dark color of this lesion; instead, the oxidation of melanin (natural pigment) with aerial oxygen is mainly responsible for this pigmentation. Such types of acne lesions are quite stable and take longer time to get cured.
• Whitehead: Sometimes excess sebum, dead skin cells, and bacterial proliferation block hair follicles below the skin, which results in a white tiny bumpy appearance on the skin surface. Hair follicles remain closed in this lesion, and so goes the name “closed comedo.” Whiteheads grow faster than blackheads. These lesions are quite odious when stick out on the skin surface and seem to be imploring to be popped.
III. Inflammatory Acne Lesions
Inflammatory lesions are mostly the outcome of the ruptured microcomedones. It may also leap out due to infected noninflammatory lesions. Basically four types of acne lesions come under this family:
Papules: Papules are characterized by small, firm, reddish pimples. These acne lesions are often considered as transitional step between non- and inflammatory lesions. These are mainly originated as a result of the reactions of local cells to acne development. These are slightly inflamed, itchy, and feel like sandpaper. These lesions are easily discernible from pustules as papules are devoid of pus.
Pustules: These closed comedones are our garden-variety blemishes. These types of acne lesions are quite similar to papules, but are more inflammatory in nature. Pustules are small, elevated, round lesions of skin. These are reddish in color with a white or yellow center, which contain noticeable pus. The pus is stored underneath the skin, which normally includes a mixture of dead skin cells, white blood corpuscles, and a little amount of bacteria. Those acne pustules, which appear over a sebaceous gland, most often center round a hair strand. The chemical reactions owing to the sebum components in the pus, for example, free fatty acids, are responsible for the irritation and inflammation. Pustules, which mend instead of turning into a cystic form, never leave any mark.
Acne Nodules: Unlike papules acne nodules are much larger in size and distinguished by intense inflammation. These types of acne lesions occur deep within the tissue layer of the skin located below the epidermis. They often feel like solid lump under the skin. Within the dermis, the wall of the blocked hair follicle tears up and the infected waste from the pore spreads out into the dermis and contaminates neighboring hair follicles. Acne nodules are severe form of acne. These are often painful, causing extreme trauma for several weeks. If squeezed to pop or kept untreated for long time, these lesions can annihilate tissues deep inside the skin, resulting in profound scarring.
Acne Cysts: Acne cysts are very large, tender, and dome shaped or often irregularly shaped protuberance on the affected area of the skin. These lesions contain huge amount of liquid or semi liquid matter. These are developed under the skin when the accumulated mass inside the comedo spills into the skin and an extreme spontaneous localized immune response takes place to put off the spread of infection throughout our other body parts. This is the most terrible form of acne lesions and is exceedingly painful in nature. The possibility of scarring is very high with these types of acne lesions. Cysts may cause much deeper and serious infection if not treated and cured quickly.