Doctor123.org

Furunculosis

BASICS

DESCRIPTION

- Predominant age - Adolescents and young adults - Clusters have been reported in teenagers living in crowded quarters, within families, or in high school athletes.

- Resistant strains of S. aureus (MRSA): clindamycin 300 mg q6h or doxycycline 100 mg q12h or trimethoprim-sulfamethoxazole (TMP-SMX DS) 1 tab q8-12h or minocycline 100 mg q12h - If known or suspected impaired neutrophil function (e.g., impaired chemotaxis, phagocytosis, superoxide generation), add vitamin C 1,000 mg/day for 4 to 6 weeks (prevents oxidation of neutrophils). - If antibiotic regimens fail: - May try PO pentoxifylline 400 mg TID for 2 to 6 months - Contraindications: recent cerebral and/or retinal hemorrhage; intolerance to methylxanthines (e.g., caffeine, theophylline); allergy to the particular drug selected - Precautions: prolonged prothrombin time (PT) and/or bleeding; if on warfarin, frequent monitoring of PT

  • Acute bacterial abscess of a hair follicle (often Staphylococcus aureus)
  • System(s) affected: skin/exocrine
  • Synonym(s): boils

EPIDEMIOLOGY

Incidence

  • Predominant ageAdolescents and young adultsClusters have been reported in teenagers living in crowded quarters, within families, or in high school athletes.
  • Predominant sex: male = female

Prevalence

Exact data are not available.

ETIOLOGY AND PATHOPHYSIOLOGY

  • Infection spreads away from hair follicle into surrounding dermis.
  • Pathogenic strain of S. aureus (usually); most cases in United States are now due to community-acquired methicillin-resistant S. aureus (CA-MRSA) whereas methicillin-sensitive S. aureus (MSSA) is most common elsewhere (1).

Genetics

Unknown

RISK FACTORS

  • 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
  • Primary immunodeficiency disease and AIDS (common variable immunodeficiency, chronic granulomatous disease, Chediak-Higashi syndrome, C3 deficiency, C3 hypercatabolism, transient hypogammaglobulinemia of infancy, immunodeficiency with thymoma, Wiskott-Aldrich syndrome)
  • Secondary immunodeficiency (e.g., leukemia, leukopenia, neutropenia, therapeutic immunosuppression)
  • Medication impairing neutrophil function (e.g., omeprazole)
  • The most important independent predictor of recurrence is a positive family history.

GENERAL PREVENTION

Patient education regarding self-care (see "General Measures"); treatment and prevention are interrelated.

COMMONLY ASSOCIATED CONDITIONS

  • Usually normal immune system
  • Diabetes mellitus
  • Polymorphonuclear leukocyte defect (rare)
  • Hyperimmunoglobulin E-Staphylococcus sp. abscess syndrome (rare)
  • See "Risk Factors."

DIAGNOSIS

HISTORY

  • Located on hair-bearing sites, especially areas prone to friction or repeated minor traumas (e.g., underneath belt, anterior aspects of thighs, nape, buttocks)
  • No initial fever or systemic symptoms
  • The folliculocentric nodule may enlarge, become painful, and develop into an abscess (frequently with spontaneous drainage).

PHYSICAL EXAM

  • Painful erythematous papules/nodules (1 to 5 cm) with central pustules
  • Tender, red, perifollicular swelling, terminating in discharge of pus and necrotic plug
  • Lesions may be solitary or clustered.

DIFFERENTIAL DIAGNOSIS

  • Folliculitis
  • Pseudofolliculitis
  • Carbuncles
  • Ruptured epidermal cyst
  • Myiasis (larva of botfly/tumbu fly)
  • Hidradenitis suppurativa
  • Atypical bacterial or fungal infections

DIAGNOSTIC TESTS & INTERPRETATION

Initial Tests (lab, imaging)

Obtain culture if with multiple abscesses marked by surrounding inflammation, cellulitis, systemic symptoms such as fever, or if immunocompromised.

Follow-Up Tests & Special Considerations

  • Immunoglobulin levels in rare (e.g., recurrent or otherwise inexplicable) cases
  • If culture grows gram-negative bacteria or fungus, consider polymorphonuclear neutrophil leukocyte functional defect.

Test Interpretation

Histopathology (although a biopsy is rarely needed)

  • Perifollicular necrosis containing fibrinoid material and neutrophils
  • At deep end of necrotic plug, in SC tissue, is a large abscess with a Gram stain positive for small collections of S. aureus.

TREATMENT

GENERAL MEASURES

  • Moist, warm compresses (provide comfort, encourage localization/pointing/drainage) 30 minutes QID
  • If pointing or large, incise and drain: consider packing if large or incompletely drained.
  • Routine culture is not necessary for localized abscess in nondiabetic patients with normal immune system.
  • Sanitary practices: change towels, washcloths, and sheets daily; clean shaving instruments; avoid nose picking; change wound dressings frequently; do not share items of personal hygiene (2)[B].

MEDICATION

First Line

  • Systemic antibiotics usually unnecessary, unless extensive surrounding cellulitis or fever
  • If suspecting MRSA, see "Second Line."
  • If multiple abscesses, lesions with marked surrounding inflammation, cellulitis, systemic symptoms such as fever, or if immunocompromised: place on antibiotics therapy directed at S. aureus for 10 to 14 days.Dicloxacillin (Dynapen, Pathocil) 500 mg PO QID or cephalexin 500 mg PO QID or clindamycin 300 mg TID, if penicillin-allergic

Second Line

  • Resistant strains of S. aureus (MRSA): clindamycin 300 mg q6h or doxycycline 100 mg q12h or trimethoprim-sulfamethoxazole (TMP-SMX DS) 1 tab q8-12h or minocycline 100 mg q12h
  • If known or suspected impaired neutrophil function (e.g., impaired chemotaxis, phagocytosis, superoxide generation), add vitamin C 1,000 mg/day for 4 to 6 weeks (prevents oxidation of neutrophils).
  • If antibiotic regimens fail:May try PO pentoxifylline 400 mg TID for 2 to 6 monthsContraindications: recent cerebral and/or retinal hemorrhage; intolerance to methylxanthines (e.g., caffeine, theophylline); allergy to the particular drug selectedPrecautions: prolonged prothrombin time (PT) and/or bleeding; if on warfarin, frequent monitoring of PT

ONGOING CARE

FOLLOW-UP RECOMMENDATIONS

Patient Monitoring

Instruct patient to see physician if compresses are unsuccessful.

DIET

Unrestricted

PROGNOSIS

  • Self-limited: usually drains pus spontaneously and will heal with or without scarring within several days.
  • Recurrent/chronic: may last for months or years
  • If recurrent, usually related to chronic skin carriage of staphylococci (nares or on skin). Treatment goals are to decrease or eliminate pathogenic strain or suppress pathogenic strain.Culture nares, skin, axilla, and perineum (culture nares of family members).Mupirocin 2%: Apply to both nares BID for 5 days each month.Culture anterior nares every 3 months; if failure, retreat with mupirocin or consider clindamycin 150 mg/day for 3 months.
  • Especially in recurrent cases, wash entire body and fingernails (with nailbrush) daily for 1 to 3 weeks with povidone-iodine (Betadine), chlorhexidine (Hibiclens), or hexachlorophene (pHisoHex soap), although all can cause dry skin.

COMPLICATIONS

  • Scarring
  • Bacteremia
  • Seeding (e.g., septal/valve defect, arthritic joint)

REFERENCES

11 Demos M, McLeod MP, Nouri K. Recurrent furunculosis: a review of the literature. Br J Dermatol. 2012;167(4):725-732.22 Fritz SA, Camins BC, Eisenstein KA, et al. Effectiveness of measures to eradicate Staphylococcus aureus carriage in patients with community-associated skin and soft-tissue infections: a randomized trial. Infect Control Hosp Epidemiol. 2011; 32(9):872-880.

ADDITIONAL READING

  • El-Gilany AH, Fathy H. Risk factors of recurrent furunculosis. Dermatol Online J. 2009;15(1):16.
  • Ibler KS, Kromann CB. Recurrent furunculosis-challenges and management: a review. Clin Cosmet Investig Dermatol. 2014;7:59-64.
  • McConeghy KW, Mikolich DJ, LaPlante KL. Agents for the decolonization of methicillin-resistant Staphylococcus aureus. Pharmacotherapy. 2009;29(3):263-280.
  • Rivera AM, Boucher HW. Current concepts in antimicrobial therapy against select gram-positive organisms: methicillin-resistant Staphylococcus aureus, penicillin-resistant pneumococci, and vancomycin-resistant enterococci. Mayo Clin Proc. 2011;86(12):1230-1243.
  • Wahba-Yahav AV. Intractable chronic furunculosis: prevention of recurrences with pentoxifylline. Acta Derm Venereol. 1992;72(6):461-462.
  • Winthrop KL, Abrams M, Yakrus M, et al. An outbreak of mycobacterial furunculosis associated with footbaths at a nail salon. N Engl J Med. 2002;346(18):1366-1371.

SEE ALSO

Folliculitis; Hidradenitis Suppurativa

CODES

ICD10

  • L02.92 Furuncle, unspecified
  • L02.12 Furuncle of neck
  • L02.429 Furuncle of limb, unspecified
  • L02.32 Furuncle of buttock
  • L02.425 Furuncle of right lower limb
  • L02.422 Furuncle of left axilla
  • L02.426 Furuncle of left lower limb
  • L02.621 Furuncle of right foot
  • L02.424 Furuncle of left upper limb
  • L02.423 Furuncle of right upper limb
  • L02.229 Furuncle of trunk, unspecified
  • L02.222 Furuncle of back [any part, except buttock]
  • L02.02 Furuncle of face
  • L02.629 Furuncle of unspecified foot
  • L02.622 Furuncle of left foot
  • L02.821 Furuncle of head [any part, except face]
  • L02.221 Furuncle of abdominal wall
  • L02.225 Furuncle of perineum
  • L02.828 Furuncle of other sites
  • L02.529 Furuncle unspecified hand
  • L02.224 Furuncle of groin
  • L02.226 Furuncle of umbilicus
  • L02.421 Furuncle of right axilla
  • L02.223 Furuncle of chest wall
  • L02.522 Furuncle left hand
  • L02.521 Furuncle right hand

ICD9

  • 680.9 Carbuncle and furuncle of unspecified site
  • 680.1 Carbuncle and furuncle of neck
  • 680.3 Carbuncle and furuncle of upper arm and forearm
  • 680.5 Carbuncle and furuncle of buttock
  • 680.4 Carbuncle and furuncle of hand
  • 680.8 Carbuncle and furuncle of other specified sites
  • 680.0 Carbuncle and furuncle of face
  • 680.2 Carbuncle and furuncle of trunk
  • 680.6 Carbuncle and furuncle of leg, except foot
  • 680.7 Carbuncle and furuncle of foot

SNOMED

  • 40603000 Furunculosis of skin AND/OR subcutaneous tissue (disorder)
  • 47763005 Furuncle of neck (disorder)
  • 60198007 Furuncle of axilla
  • 12430003 Furuncle of buttock (disorder)
  • 37396007 Furuncle of face
  • 67272008 Furuncle of trunk (disorder)
  • 90942002 Furuncle of thigh
  • 2606006 Furuncle of perineum

CLINICAL PEARLS

  • Pathogens may be different in different localities. Keep up-to-date with the locality-specific epidemiology.
  • If few, furuncles/furunculosis do not need antibiotic treatment. If systemic symptoms (e.g., fever), cellulitis, or multiple lesions occur, oral antibiotic therapy is used.
  • Other treatments for MRSA include linezolid PO or IV and IV vancomycin.
  • Folliculitis, furunculosis, and carbuncles are parts of a spectrum of pyodermas.
  • Other causative organisms include aerobic (e.g., Escherichia coli, Pseudomonas aeruginosa, and Streptococcus faecalis), anaerobic (e.g., Bacteroides, Lactobacillus, Peptobacillius, and Peptostreptococcus), and Mycobacteria.
  • Decolonization (treatment of the nares with topical antibiotic) is only recommended if the colonization was confirmed by cultures because resistance is common and treatment is of uncertain efficacy.