Folliculitis is the infection and

inflammation Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...

of one or more

hair follicle The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between h ...

s. The condition may occur anywhere on hair-covered

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...

. The rash may appear as

pimple A pimple is a kind of comedo that results from excess sebum and dead skin cells getting trapped in the pores of the skin. In its aggravated state, it may evolve into a pustule or papules. Pimples can be treated by acne medications, antibiotics, ...

s that come to white tips on the face, chest, back, arms, legs, buttocks, or head. Although

acne Acne, also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, black ...

can often involve superficial infection and inflammation of some hair follicles, the condition of those follicles is usually not called folliculitis, as that term is usually reserved for the separate set of disease entities comprising infected and inflamed hair follicles with causes other than acne.

Signs and symptoms

Histopathology of granulomatous folliculitis

Rash A rash is a change of the human skin which affects its color, appearance, or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cr ...

(reddened skin area) * Itching skin *

Pimple A pimple is a kind of comedo that results from excess sebum and dead skin cells getting trapped in the pores of the skin. In its aggravated state, it may evolve into a pustule or papules. Pimples can be treated by acne medications, antibiotics, ...

s or pustules located around a hair or follicle; may be confused with

chicken pox Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV). The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab ...

** May crust over ** Typically occur on neck, armpit, or groin ** May present as genital

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classifi ...

s * Spreading from leg to arm to body through improper treatment with antibiotics File:Sebaceaous Hyperplasia Chronic folliculits Right Mid Chest.jpg, Chronic folliculitis surrounding central sebaceous hyperplasia, right mid-chest

Complications

This condition can develop into a more severe skin condition, such as cellulitis or

abscess An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends b ...

Causes

Most carbuncles,

boil A boil, also called a furuncle, is a deep folliculitis, which is an infection of the hair follicle. It is most commonly caused by infection by the bacterium ''Staphylococcus aureus'', resulting in a painful swollen area on the skin caused by an ...

s, and other cases of folliculitis are infected with ''

Staphylococcus aureus ''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often positive ...

''. Folliculitis starts with the introduction of a skin

pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...

to a hair follicle. Hair follicles can also be damaged by

friction Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: *Dry friction is a force that opposes the relative lateral motion of t ...

from

clothing Clothing (also known as clothes, apparel, and attire) are items worn on the body. Typically, clothing is made of fabrics or textiles, but over time it has included garments made from animal skin and other thin sheets of materials and natural ...

, an insect bite, blockage of the follicle, shaving, or braids that are very tight and close to the scalp. The damaged follicles are then infected by ''Staphylococcus'' spp. Folliculitis can affect people of all ages. Iron-deficiency anemia is sometimes associated with chronic cases.

Bacterial

* ''Staphylococcus aureus'' folliculitis *

Hot-tub folliculitis Hot tub folliculitis (''pseudomonal'' folliculitis) is a common type of folliculitis, a condition which causes inflammation of hair follicles. This condition is caused by an infection of hair follicles by a non-pathogenic strain of the bacterium ' ...

is caused by the bacterium ''

Pseudomonas aeruginosa ''Pseudomonas aeruginosa'' is a common encapsulated, gram-negative, aerobic–facultatively anaerobic, rod-shaped bacterium that can cause disease in plants and animals, including humans. A species of considerable medical importance, ''P. aerugi ...

''. The folliculitis usually occurs after sitting in a hot tub that was not properly cleaned before use. Symptoms are found around the body parts that sit in the hot tub - the legs, hips, chest, buttocks, and surrounding areas. Symptoms are amplified around regions that were covered by wet clothing, such as

bathing suit A swimsuit is an item of clothing designed to be worn by people engaging in a water-based activity or water sports, such as swimming, diving and surfing, or sun-orientated activities, such as sun bathing. Different types may be worn by men, wo ...

s. * Sycosis vulgaris, sycosis barbae, or barber's itch is a staphylococcal infection of the hair follicles in the bearded area of the face, usually the upper lip. Shaving aggravates the condition. * Gram-negative folliculitis may appear after prolonged acne treatment with antibiotics.

Fungal

* Tinea barbae is similar to barber's itch, but the infection is caused by the

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

T. rubrum ''Trichophyton rubrum'' is a dermatophytic fungus in the phylum Ascomycota. It is an exclusively clonal, anthropophilic saprotroph that colonizes the upper layers of dead skin, and is the most common cause of athlete's foot, fungal infection of ...

''. *

Malassezia folliculitis Malassezia folliculitis or Pityrosporum folliculitis, is a skin condition caused by infection by ''Malassezia'' (formerly ''Pityrosporum'') yeast. The skin of the upper trunk area including the back, chest, arms and sometimes the neck is often a ...

, formerly known as ''Pityrosporum ''folliculitis, is caused by yeasts (part of the fungus kingdom) of the genus ''

Malassezia ''Malassezia'' (formerly known as ''Pityrosporum'') is a genus of fungi. It is the sole genus in family Malasseziaceae, which is the only family in order Malasseziales, itself the single member of class Malasseziomycetes. ''Malassezia'' species ...

Mites

Demodex folliculitis Demodicosis , also called Demodex folliculitis in humans and demodectic mange () or red mange in animals, is caused by a sensitivity to and overpopulation of '' Demodex spp.'' as the host's immune system is unable to keep the mites under control. ...

is usually caused by an overgrowth of '' Demodex folliculorum'' a mite that lives in human hair follicles. Although most people with ''D. folliculorurm'' have no symptoms, the mite can reproduce excessively, particularly in people with oily scalps.

Viral

* Herpetic folliculitis is rarer, but may occur when

herpes simplex virus Herpes simplex virus 1 and 2 (HSV-1 and HSV-2), also known by their taxonomical names ''Human alphaherpesvirus 1'' and '' Human alphaherpesvirus 2'', are two members of the human ''Herpesviridae'' family, a set of viruses that produce viral inf ...

infection spreads to nearby hair follicles appearing in groups or clusters, mostly around the mouth.

Noninfectious

* Pseudofolliculitis barbae is a disorder occurring when hair curves back into the skin and causes inflammation. *

Eosinophilic folliculitis Eosinophilic folliculitis is an itchy rash with an unknown cause that is most common among individuals with HIV, though it can occur in HIV-negative individuals where it is known by the eponym Ofuji disease. EF consists of itchy red bumps (papule ...

may appear in persons with impaired immune systems. *

Folliculitis decalvans Folliculitis decalvans is an inflammation of the hair follicle that leads to bogginess or induration of involved parts of the scalp along with pustules, erosions, crusts, ulcers, and scale.Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in G ...

or tufted folliculitis usually affects the scalp. Several hairs arise from the same hair follicle. Scarring and permanent hair loss may follow. The cause is unknown. * Folliculitis keloidalis scarring on the nape of the neck is most common among males with curly hair. * Oil folliculitis is inflammation of hair follicles due to exposure to various oils, and typically occurs on forearms or thighs. It is common in refinery workers, road workers, mechanics, and sheep shearers. Even makeup may cause it. * Malignancy may also be represented by recalcitrant cases.Folliculitis, follicular mucinosis, and papular mucinosis as a presentation of chronic myelomonocytic leukemia. Rashid R, Hymes S. Dermatol Online J. 2009 May 15;15(5):16.

Treatment

Most simple cases resolve on their own, but first-line treatments are typically topical medications. # Topical antiseptic treatment is adequate for most cases. # Topical

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

s, such as

mupirocin Mupirocin, sold under the brand name Bactroban among others, is a topical antibiotic useful against superficial skin infections such as impetigo or folliculitis. It may also be used to get rid of methicillin-resistant ''S. aureus'' (MRSA) when ...

neomycin/polymyxin B/bacitracin Neomycin/polymyxin B/bacitracin, also known as triple antibiotic ointment, is a medication used to reduce the risk of infections following minor skin injuries. It contains three antibiotics: neomycin, polymyxin B, and bacitracin. It is for topic ...

ointment may be prescribed. Oral antibiotics may also be used. # Some patients may benefit from systemic narrow-spectrum penicillinase-resistant penicillins (such as dicloxacillin in the US or flucloxacillin in UK). # Fungal folliculitis may require an oral antifungal such as

fluconazole Fluconazole is an antifungal medication used for a number of fungal infections. This includes candidiasis, blastomycosis, coccidiodomycosis, cryptococcosis, histoplasmosis, dermatophytosis, and pityriasis versicolor. It is also used to prevent ...

. Topical antifungals such as econazole nitrate may also be effective. Folliculitis may recur even after symptoms have gone away.

References

External links

Folliculitis Treatments

Malassezia (Pityrosporum) Folliculitis Treatment & Management
{{Bacterial cutaneous infections Conditions of the skin appendages Bacterium-related cutaneous conditions Dermal and subcutaneous growths