Paronychia Due to Candida

Candidal paronychia is a chronic inflammatory disorder of the nail folds, with loss of the cuticle and colonisation by Candida species, which cause a swollen, tender nail fold with nail plate ridging. It is a chronic irritant and allergic dermatitis in which Candida acts as a secondary colonising organism.

• Risk factors: repeated wet work, finger sucking, manicure, diabetes, HIV, corticosteroid use, Raynaud, peripheral vascular disease, oral contraceptives, atopy.
• Occupations: cleaners, bartenders, food handlers, nurses, hairdressers, housemaids.

Swollen, boggy, erythematous proximal and lateral nail folds with absent cuticle, mild tenderness, intermittent small pus pockets after pressure, and transverse ridges or discolouration (green, brown, yellow) of the nail plate.

• Usually 1 to 3 fingernails, often the middle finger and thumb; disease lasts more than 6 weeks.
• Differential diagnosis: acute bacterial paronychia, herpetic whitlow, psoriasis, eczema, lichen planus, squamous cell carcinoma, amelanotic melanoma, tinea unguium, Raynaud disease, pseudomonas infection.
• Complications: nail plate dystrophy, acute superinfection with Staphylococcus aureus or Pseudomonas, spread to adjacent fingers, chronic pain, malignancy if misdiagnosed.

Clinical; swab and KOH examination of exudate and nail fold; culture for Candida species and bacteria.

• Glucose or HbA1c, HIV test.
• Biopsy for persistent solitary lesion, bleeding or ulcer beyond 6 weeks.

Protect the nail fold from moisture and irritants, then treat inflammation and Candida.

• Supportive: keep hands dry, cotton lined waterproof gloves for wet work, avoid nail biting, manicure and cuticle removal, moisturise, avoid artificial nails, wear gloves in cold weather.
• Pharmacological: mometasone furoate 0.1 percent ointment or tacrolimus 0.1 percent ointment to the nail fold twice daily for 3 weeks (often the most effective step); clotrimazole 1 percent or miconazole 2 percent cream three times daily for 4 weeks; nystatin ointment. For resistant disease: itraconazole 200 mg daily for 1 month, or fluconazole 150 to 200 mg once weekly for 4 to 6 weeks. For bacterial superinfection: flucloxacillin 500 mg four times daily for 7 days.
• Procedures: drainage of any abscess; surgical eponychial marsupialisation for refractory disease; avulse the nail only for severe dystrophy.
• Special groups: pregnancy, topical clotrimazole and topical steroid only; children, topical care and stop finger sucking; diabetes, optimise glucose control; liver disease, avoid oral antifungals.
• Red flags: acute painful throbbing with pus, red streaks, fever, destructive or ulcerated fold, pigmentation, persistent beyond 6 months, non response.
• Follow-up: review at 3 to 4 weeks; skin protection must continue for at least 6 months to allow cuticle regrowth.