Furunculosis (Boils)

Introduction

Furunculosis (which is also called Boils) is an infection of a hair follicle by staphylococcal organisms, that leads to an inflammation.
A carbuncle is merely two or more confluent furuncles, with separate heads nodule, with a pustular centre.
Recalcitrant cases of furunculosis may occur with a background of:

  1. immune suppression
  2. Alcoholism
  3. Malnutrition
  4. Blood dyscrasias
  5. Disorders of neutrophil function
  6. Diabetes
  7. AID

Boils may occur in patients with atopic dermatitis.
It may be iatrogenic

Symptoms and clinical features of furunculosis (boils)

  1. It can be found on all body sites where hairs are present.
  2. It starts with a small, yellow creamy
    pustule that rapidly evolves into a red nodule, often with a central yellow plug
  3. As the lesion expands, it becomes:
    • Painful and tense
    • associated with local oedema, lymphangitis, regional lymphadenopathy and fever
    • Eventually, the central part of the nodule becomes soft and drains spontaneously
      Healing occurs after about 1 – 2 weeks with scar formation

Differential diagnoses

  • Folliculitis
  • Cutaneous myiasis
  • Acne inversa in the axilla or groin

Complications of furunculosis (boils)

  1. Cellulitis
  2. Septicaemia
  3. Carvenous sinus thrombosis when the lesions are on the head and neck.

Investigations

  • Wound swab for bacteriology and sensitivity
  • Full Blood Count with differentials
  • Fasting blood glucose
  • HIV screening
  • Urinalysis

Treatment for furunculosis (boils)

Treatment objectives

  1. Treat infection
  2. Correct predisposing factors
  3. Prevent complications

Drug treatment

1. Drainage 

Abscesses are incised and drained. Intermittent hot compresses are used to facilitate drainage.

2. Topical antibiotics 

For mild cases (few pustules without fever or systemic manifestations)
Mupirocin ointment,
Adults and children:

  • Apply 12 hourly for 7 days

Or

Gentamicin 0.3% cream 

  • Apply 12 hourly for 7 days

3. Systemic antibiotics 

This is usually unnecessary except for head and neck lesions, or when the boil is accompanied by fever, chills, regional lymphadenopathy, or a feeling of being unwell and in immunocompromised patients.
Note that resistance may set in with prolonged use of Systemic antibiotics.
Co-trimoxazole

  • Adult: 960 mg orally every 12 hours for 5-10 days
  • Child:
    • 6 weeks – 5 months: 120 mg;
    • 6 months -5 years: 240 mg; 6-12 years: 480 mg taken orally every 12 hours for 5-10 days

Or

Clindamycin

  • Adult: 300 to 600 mg orally every 6 to 8 hours:

Or

Doxycycline or minocycline

  • Adult: 100 mg orally every 12 hours.

Or

Erythromycin

  • Adult and child over 8years 250-500 mg orally every 6 hours or-1g 12 hourly for 5-10 days
  • Child:
    • up to 2 years: 125 mg orally every 6 hours;
    • 2-8 years: 250 mg every 6 hours for 5 10days

Surgical treatment

  • A small puncture wound often gives less of a scar than allowing spontaneous rupture; it also reduces the pain
  • Should be under antibiotic cover to prevent septicaemia

Recurrent furunculosis (boils) Prevention

To prevent furunculosis (boils) from becoming recurrent:

  1. Treat possible predisposing factors such as obesity, diabetes etc
  2. Apply liquid soap containing either chlorhexidine gluconate with isopropyl alcohol or 2 to 3% chloroxylenol
  3. Give maintenance antibiotics over 1 to 2 months.

Referral Criteria

Refer for hospital care and treatment if spreading rapidly or cellulitis, osteomyelitis or septicaemia develops.