In most patients, clinical examination of the skin reveals a single erythematous papule, pustule or nodule that is tender and painful to touch. Adjacent redness of the skin may be present. Sometimes, more than one furuncle may develop in a relatively small area. Coalescence of several furuncles is called a carbuncle. Some of them may be draining pus, and they may also develop in several anatomic locations simulatenously. Closer inspection will reveal that furuncles develop at the center of the hair follicle, and constitutional symptoms, such as fever, malaise, and local lymphadenopathy occur only if the infection is severe.

As mentioned previously, furuncles can develop in any hair-bearing areas, but are most commonly found in the head and neck area, proximal extremities, including axilla, groins, and the gluteal region [9].

• Splenomegaly

  Chronically infected fish show visceral congestion, multiple haemorrhage in the muscle and liver, splenomegaly, necrosis of the kidney, adhesions of the viscera and intestinal inflammation. [gov.scot]

• Pain

  The boils usually started with a painful or itchy red papule or pustule. Some of these lesions spontaneously involuted, but most progressed to painful nodules that later drained significant quantities of pus, with relief to the pain. [medicinetoday.com.au]

  You may also have other symptoms, such as fever, chills, fatigue, or pain. How are furunculosis and carbunculosis diagnosed? Your healthcare provider will examine your skin. [drugs.com]

  Pain Erythema and edema may persist for several weeks. In Carbunculosis: the patient develops extremely painful deep abscesses. These drain through multiple openings onto the skin surface, usually around several hair follicles. [doctor-clinic.org]

  The furuncles are painful and swollen bumps on the skin, in which pus and dead skin cells tend to accumulate. [medicalpoint.org]

  Symptoms: A furuncle generally starts as an itchy, red, painful lump.Over time, the area becomes large, firm and hard. There is redness and swelling around the furuncle. The area is usually painful and warm to touch. May weep, ooze, curst. [medigoo.com]

• Fever

  You may also have other symptoms, such as fever, chills, fatigue, or pain. How are furunculosis and carbunculosis diagnosed? Your healthcare provider will examine your skin. [drugs.com]

  They may be accompanied by fever and prostration. Clinical evaluation Culture of lesion Diagnosis is by examination. Material for culture should be obtained. Drainage Often antibiotics effective against MRSA Abscesses are incised and drained. [msdmanuals.com]

  […] can vary tremendously, from the size of a pea to golf size The center of the furuncle can present a yellow or a white dot, especially when the furuncle is about to discharge pus Severe infections can lead to systemic symptoms, including high running fever [medicalpoint.org]

  Patients with fever, multiple abscesses, or carbuncles are given 10 days of TMP/SMX 160/800 mg to 320/1600 mg 2 times a day plus rifampin 300 mg 2 times a day. [merckmanuals.com]

  Closer inspection will reveal that furuncles develop at the center of the hair follicle, and constitutional symptoms, such as fever, malaise, and local lymphadenopathy occur only if the infection is severe. [symptoma.com]

• Inflammation

  Orbital inflammation secondary to sinus inflammation is a well known entity and has been widely reported. However, nasal furunculosis resulting in orbital inflammation is a rare occurrence. [ncbi.nlm.nih.gov]

  After some time, the area of inflammation begins to increase in size. Tissue around the inflammation becomes painful and swollen. After three days from the beginning of the disease, there begins to form suppurative rod. [euromd.com]

  Chronically infected fish show visceral congestion, multiple haemorrhage in the muscle and liver, splenomegaly, necrosis of the kidney, adhesions of the viscera and intestinal inflammation. [gov.scot]

  This leads to inflammation and eventually to the formation of pus (A fluid product of inflammation, consisting of a liquid containing leukocytes and the debris of dead cells and tissue elements liquefied by the proteolytic and histolytic enzymes that [medigoo.com]

  A furuncle (boil) is a skin disease caused by deep purulent inflammation of a hair follicle and a nearby sebaceous gland. If boils spread all over the body, the disease is called furunculosis. [online-dermatologist.com]

• Swelling

  In this report, the authors presented a 49-year-old woman with 4-day history of focal red area and tender swelling on the tip of her nose. [ncbi.nlm.nih.gov]

  Introduction The first authentic report of furunculosis was described as early as 1894 in a brown trout hatchery in Bavaria, Germany and was characterised by furuncle-like swellings and ulcerative lesions on infected trout. [gov.scot]

  You have increased pain, redness, or swelling around the infected area. You have questions or concerns about your condition or care. Care Agreement You have the right to help plan your care. [drugs.com]

• Sepsis

  It is therefore probable that the hypogammaglobulinaemia played a pathogenic role in the development of cutaneous sepsis. [ncbi.nlm.nih.gov]

  Sepsis Bacteremia is an infection of the bloodstream that may occur after having a bacterial infection, such as a furuncle. If untreated, it can lead to severe organ dysfunction such as sepsis. [healthline.com]

  […] few immunocompromised patients, in particular children, most patients have skin carriage of S. aureus as their only risk factor 1 A furuncle which is suboptimally managed may progress to 1: carbuncle (a cluster of furuncles) cellulitis skin abscess sepsis [radiopaedia.org]

  […] disappear without any special treatment, at the first sight, you should always keep in mind a few rules: Do not remove boil rod yourself, since this may lead to the spreading of infection to other parts of the body, as well as acute thrombophlebitis and sepsis [euromd.com]

• Furunculosis

  Furunculosis was generally considered a disease of salmonids, but many other species have been shown to be susceptible including eel, bass, perch, carp, cod, turbot and wrasse. [gov.scot]

  Search terms used were 'furunculosis', 'recurrent furunculosis', 'skin abscess' and 'recurrent boils'. Articles were discarded if they did not refer to furunculosis secondary to S. aureus. [ncbi.nlm.nih.gov]

  […] soft tissue infections: furunculosis, pyoderma and impetigo en Otitis media, bronchitis, sinusitis, furunculosis, bacterial infection, viral infections es Mejor que bien, diviértete... mira a esas nenas tan interesantes en ; Pike (Esox lucius); Turbot [es.glosbe.com]

  Furunculosis rarely leads to systemic infection with fever and organ related symptoms, but endocarditis, respiratory distress and pneumonia, necrotizing fasciitis, and myositis have been described due to furunculosis. [symptoma.com]

• Ulcer

  Introduction The first authentic report of furunculosis was described as early as 1894 in a brown trout hatchery in Bavaria, Germany and was characterised by furuncle-like swellings and ulcerative lesions on infected trout. [gov.scot]

  Ulcer ulcera, She is suffering from a gastric ulcer / A common form of mouth ulcer, canker sores occur in women more often than in men. / gastric/stomach ulcer [dictionary.studysite.org]

  Latin fūruncul(us) (see furuncle) + -osis 1885–90 Collins Concise English Dictionary © HarperCollins Publishers:: furunculosis /fjʊˌrʌŋkjʊˈləʊsɪs/ n a skin condition characterized by the presence of multiple boils an infectious ulcerative disease of salmon [wordreference.com]

• Dermatitis

  […] en Ingrown hair, oedema face, dermatitis, oedema mouth, papular rash, bleeding skin, herpes simplex, eczema, cheilitis, furunculosis, contact dermatitis, abnormal hair texture and abnormal hair growth, hypopigmentation, flushing skin, lip numbness, skin [es.glosbe.com]

  Zinc-responsive dermatitis Zinc deficiency. Drug eruption Skin: toxic epidermal necrolysis. Superficial necrolytic dermatitis Hepatocutaneous syndrome. Pathophysiology Predisposing factor → entry of Staphylococcus intermedius → deep pyoderma. [vetstream.com]

  Histologic examination revealed suppurative granulomatous dermatitis. Mycobacterium bolletii/M massiliense was identified by sequencing the 16S ribosomal RNA (rRNA) and hsp65 genes. [ncbi.nlm.nih.gov]

  Carriage of pathogenic strain of Staphylococcus sp. in nares, skin, axilla, and perineum Rarely, polymorphonuclear leukocyte defect or hyperimmunoglobulin E–Staphylococcus sp. abscess syndrome Diabetes mellitus, malnutrition, alcoholism, obesity, atopic dermatitis [unboundmedicine.com]

  Antimicrobial susceptibility of skin-colonizing S. aureus strains in children with atopic dermatitis. Pediatr Allergy Immunol. 2004;15:474-7. Demircay Z, Eksioglu-Demiralp E, Ergun T, Akoglu T. [ijmedicine.com]

• Skin Lesion

  The high-producing strains caused more intense skin lesions. [ncbi.nlm.nih.gov]

  Furunculosis is named for the raised muscle lesions resembling skin boils (furuncles), which occur in chronically infected fish (See illustration on Fish Diseases page). [njfishandwildlife.com]

  lesions with tar or with occlusive therapy, using steroids. [doctor-clinic.org]

  lesion with a discharge. [radiopaedia.org]

• Sweating

  […] of fistulous tracts between infected hair follicles • Staphylococci and anaerobic diphtheroids are most common organisms • Hidradenitis suppurativa is a serious skin infection of the axillae or groin consisting of multiple abscesses of the apocrine sweat [accesssurgery.mhmedical.com]

  Sometimes, when multiple boils occurred, the patient felt unwell with a mild fever but no sweats. Bad flares could take up to two months to settle but treatment with cephalexin 500 mg three times daily hastened recovery. [medicinetoday.com.au]

  Furuncles are red, painful nodules and usually occur in areas affected by sweat and friction. Treatment involves hygiene, warm compresses, and sometimes incision and drainage and/or antibiotics. References Stulberg DL, Penrod MA, Blatny RA. [link.springer.com]

  Avoid leisure activities which cause sweating and friction from clothing, such as squash and jogging. 7. Antiseptic or antibiotic ointment or gel to apply to the inside of the nostrils. 8. [streetdirectory.com]

• Headache

  The patient had an uneventful postoperative recovery with no neurologic deficits, and his headache and neck stiffness were totally alleviated. [ruralneuropractice.com]

  Now she is concerned that she may have “side effects” from IVIG Gammagard as she always develops a headache the same night IVIG is given, which usually lasts about 3-4 days then disappears on its own. [aaaai.org]

  Haug Browse recently published Learning/CME Learning/CME View all learning/CME CME Case 3-2019: A 70-Year-Old Woman with Fever, Headache, and Progressive Encephalopathy Caplacizumab Treatment for Acquired Thrombotic Thrombocytopenic Purpura Randomized [nejm.org]

• Confusion

  Non-follicular eruptions sometimes confused with folliculitis include: Miliaria Papular eczema Miliaria Hidradenitis suppurativa is sometimes mistaken for boils. [dermnetnz.org]

  […] furunculosis and was associated with epidemic cases. 3 Some studies reported the same prevalence of PVL in furunculosis 4, while others had much higher prevalence. 5 It depends on the population (hospital, community), on the definition of furunculosis (confusion [dermquest.com]

Diagnosis is primarily made during the clinical examination, and once the suspicion toward furunculosis is made, workup includes identification of the causative agent, which is done by performing cultures from swabs obtained at the site of infection. Additional laboratory investigations should include urine and blood glucose, as well as glycated hemoglobin (HBA1c) to identify possible diabetes mellitus as an underlying disease. If symptoms of other than localized skin infection are present, a complete blood count (CBC), as well as other laboratory tests should be performed to investigate possible systemic infection.

In patients with recurrent furunculosis, immunological investigations should be conducted, to exclude other possible underlying causes such as HIV, malignancies, or autoimmune diseases.

Apart from microbiological and laboratory tests, patient history and the rest of the physical examination might reveal details about the underlying cause, such as poor hygiene and increased perspiration which can be encountered among athletes, or the obese.

• Staphylococcus Aureus

  A nasal swab was taken to identify nasal Staphylococcus aureus carriers. Staphylococcus aureus was the causative organism in 89 percent and 100 percent of recurrent and non-recurrent furuncles, respectively. [escholarship.org]

  Furuncles appear on the hair-bearing parts of the skin and the infectious agent is Staphylococcus aureus. [dovepress.com]

  What you should be alert for in the history Furuncles are most commonly a manifestation of a Staphylococcus aureus infection. Most individuals with furunculosis are nasal carriers of S. aureus. [dermatologyadvisor.com]

Treatment of furunculosis depends on the severity of infection, and can be either localized or systemic, but sometimes both therapies may be used. Sometimes, furuncles spontaneously burst and pus is drained onto the skin, but treatment is often necessary. particularly for larger lesions.

Localized therapy includes incision and draining of abscesses, using a scalpel blade. Application of heat and warm compresses provide consolidation of tissue and facilitate pus drainage. These methods are often sufficient in resolving this infection. However, in the presence of carbuncles, severe localized infection, or possible systemic infection, antibiotic therapy is necessary to eradicate the pathogen and resolve the infection.

When localized therapy does lead to cure, or if there is presence of single large furuncle (>5mm), oral antibiotic therapy is initiated. Systemic therapy is initiated if lesions do not resolve after initial antibiotic treatment, if there are signs of expanding infections, and if patients are immunosuppressed or at risk for endocarditis.

It is crucial to obtain swab cultures when antibiotic therapy is necessary, in order to get data regarding antimicrobial susceptibility, which is the key in choosing optimal antibiotic therapy [10]. However, due to the fact that these results often take at least a few days, empiric therapy is often initiated, and should be directed primarily against MRSA.

Guidelines suggest the use of double strength (DS) trimethoprim-sulfamethoxzole (TMP-SMX) 160/800mg po bid, clindamycin 300-450mg po tid, and doxycycline/minocycline 100mg po bid, for 5-10 days as empiric agents, with rifampicin 600mg po q24h being considered as adjunctive therapy [11]. If patients are at risk for endocarditis or systemic infection, treatment includes administration of vancomycin 15/20 mg/kg IV q8-12h, or daptomycin 6 mg/kg IV q24h [12].

For patients in whom the suggested treatment regimens did not resolve the infection, final resort includes the use of daptomycin in higher doses (8-12 mg/kg q24h), linezolid 600mg IV/po q12h, talavancin 10mg/kg IV q24h, or ceftaroline 600mg IV q8h.

Most cases of furunculosis resolve, with or without therapy, whether local therapy is used, or with administration of antibiotics. Usually, the most common complications of furunculosis are scarring and recurrence, but more severe infections may occur.

Recurrent furunculosis implies development of new furuncles despite all therapeutic measures, and certain individuals are not able to prevent the repeated occurrence of these lesions. This can be a troubling issue for patients, since boils in areas like the ear canal or nose can be very painful.

If several furuncles develop relatively close to each other, they can coalesce and form carbuncles, which are very large pus-draining lesions which increases the risk of developing a more severe infection of the skin, such as cellulitis, but also an infection that involves another site apart from the skin.

Furunculosis rarely leads to systemic infection with fever and organ related symptoms, but endocarditis [6], respiratory distress and pneumonia [7], necrotizing fasciitis, and myositis have been described due to furunculosis [8].

A particular issue in resolving furunculosis is if the causative agent is MRSA, which is resistant to the majority of antibiotics used to treat conventional staphylococcal infections, but these strains are also more virulent and cause more severe infections.

The causative agent of furunculosis, Staphylococcus aureus, is commonly found on the skin of many individuals, and it is established that about 10-20% of the population are carriers of this pathogen. It can be found on nares and nostrils, armpits, on groins, and other areas of the body, and can be transferred to other sites via finger nails, or from the nostrils. A particular issue is carriage of methicillin-resistant Staphylococcus aureus (MRSA), which is responsible for more severe infections, but also difficult to treat due to resistance to the majority of antibiotics.

Furunculosis can develop in any individual regardless of age and sex. However, it is observed that this infection most commonly develops among male teenagers and young adults.

The majority of patients who develop furuncules are healthy, and have no underlying diseases [2]. However certain predisposing factors have been identified, and include: disruption of skin integrity through breaks and injury, poor hygiene, chronic carrier state of S. aureus, obesity, increased sweating, diabetes mellitus, and other immunosuppressive disorders (such as human immunodeficiency virus (HIV) infection). Preexisting skin infections, such as atopic dermatitis, leg ulcers, chronic wounds, or abnormal follicular anatomy (for e.g. comedones in acne) also predispose individuals to furunculosis [3], and certain chemotactic defects and enzyme deficiencies, such as mannose-binding lectin deficiency, have been described as risk factors for development of this infection [4] [5].

Clustered cases may be seen among those living in crowded areas with relatively poor hygiene, or among those who were in close contact with individuals with active infection. Hot and humid climates also contribute to the development of furuncles.

Disruption of normal skin integrity is thought to be the key in the pathogenesis of furunculosis. Namely, through cuts and breaks in the skin bacteria can penetrate tissue more easily, and descend into the wall of the hair follicle. Once bacteria reach the follicle, inflammation and infection occurs, leading to the formation of folliculitis, and accompanying inflammation of adjacent tissue leads to the development of furuncles. By definition, furunculosis develops in preexisting folliculitis, and leads to formation of abscess at the site of infection. The abscess consists of a fibrin wall surrounded by inflammatory tissue enclosing a central core of pus filled with bacteria and their products, as well as migrating leukocytes. Once the formation of abscesses occur, a potential risk of severe infection through hematogenous spread may occur, and cause infections in other organs, such as endocarditis, glomerulonephritis, osteomyelitis, arthritis, and can even reach the central nervous system and cause meningitis. It is important to mention that even smaller abscesses can be a source of systemic infection, which can be life threatening, but this is a rare occurrence.

In the case of furunculosis, prevention may play a key role in reducing the burden caused by this infection. Since poor hygiene is considered to be a major risk factor for the development of furuncles, preventive educational information on personal hygiene, and appropriate wound care are highly recommended for all individuals, especially for those with virtually any type of skin infections, including furunculosis [13] [14]. Proper hygiene is very effective, and primarily involves good personal hygiene with regular bathing, and hand-washing with soap and water, and cleansing with an alcohol-based hand gel after being in contact with infected skin or wounds. Sharing of items used on infected skin, such as razors, towels, linen, etc. should be avoided, and individuals should minimize close contact with wounds and injured skin of others.

Diet has also been mentioned as a potential risk factor, and the hypothesis of increased intake of sugars making individuals more susceptible to furunculosis is a topic of numerous research papers. These suggest that a controlled intake of sugars may decrease the risk of this infection.

Furunculosis is a skin infection due to Staphylococcus aureus in virtually all cases. This infection involves the hair follicle and adjacent tissue. Furunculosis may occur in individuals of any age and sex, but most commonly occurs among young males, and rarely appears before puberty. Infection occurs due to penetration of bacteria into previously damaged skin, or other predisposing factors (such as diabetes mellitus, or poor hygiene), leading to inflammation and abscess formation [1]. The characteristic lesion - furuncle (also known as boil) - presents as a single firm, erythematous, tender nodule that can be up to a few centimeters in diameter, which arises from the hair follicle. It can appear in any hair-bearing area, the most common being the head, neck, the axilla, and the gluteal region. Diagnosis is achieved by recognizing the skin lesion on physical examination, and workup should include swab cultures to identify the causative agent. Additional tests should be done to rule out any underlying causes that may predispose patients to this condition. Furuncles may resolve spontaneously, but treatment can be sometimes necessary, and comprises local therapy, including incision and drainage of abscesses and warm compresses, and antibiotics if the infection is severe. Furunculosis resolves with therapy in most cases, but recurrent furunculosis, formation of carbuncles (coalescence of several furuncles, which can lead to scarring and deeper infection) or systemic infection may arise as complications if not treated properly.

Furunculosis is a bacterial infection of the skin. Furuncles are small, red, tender and initially superficial collections of pus that are called abscesses and cause inflammation of the hair follicle and the adjacent tissue. Several risk factors, such as poor hygiene and skin care, as well as underlying ilnesses such as diabetes mellitus, or other immunosuppressive diseases predispose individuals to this infection. It most commonly affects young males, and typical occurs on the neck, face, groins and buttocks. They are uncomfortable and may be very painful when closely attached to underlying structures (for example, on the nose, ears, or fingers). If furunculosis does not resolve spontaneously, or with therapy, bacteria may spread from this lesion to infect the surrounding tissue, which may cause a more severe infection with symptoms such as fever and malaise, requiring therapy with antibiotics. However, furuncles are usually treated with local application of warm compresses and incision of these abscesses, as well as drainage of accumulated pus. This procedure is performed exclusively by medical personnel, and should never be attempted at home. Local therapy is usually effective, and resolves the infection in most cases. If not, antibiotic therapy, depending upon the antibiotic to which the bacterial organism is most susceptible should be given. It is important to mention that hygiene and sanitary measures are crucial in preventing this skin infection, through regular bathing, hand-washing, and cleansing of affected skin area, because furunculosis may be recurrent, and cause chronic skin issues, which may be debilitating.

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