Acute paronychia

Acute paronychia is an acute inflammation of the nail bed, usually caused by a bacterial infection such as Staphylococcus aureus, producing an abscess which extends under the nail.

Cuticle or nail fold trauma caused by direct or indirect methods provides the opportunity for bacteria to enter the nail bed and cause infection e.g. - minor trauma caused by dishwashing, splinter or thorn injury to a finger, nail biting, and manicure procedure (1), an ingrown nail, thumb sucking in children (2)

Aetiological agents include

• Staphylococcus aureus (most frequent cause), Streptococcus pyogenes, Pseudomonas pyocyanea, Proteus vulgaris (1)
• anaerobes - secondary to finger sucking (2)
• gram negative bacilli, herpes simplex virus, dermatophytes and yeasts have also been reported (3)

It may also develop as a complication of chronic paronychia (1) or rarely as a presentation of pemphigus vulgaris (PV) (4).

Early paronychia is treated with a short course of oral antibiotics and saline soaks. More extensive infection is treated with antibiotics and drainage:

• if pus is visible and extends away from the nail fold, it may be incised at this site
• pus trapped beneath the nail requires excision of the proximal third of the nail with elevation of the paronychia; the paronychia is often held open by interposing gauze. The gauze is removed after 2-3 days.
• an alternative for extensive infection is removal of the entire nail bed with paronychial elevation

Post-operatively, the hand should be dressed with gauze and movement encouraged.

Reference:

• (1) Rigopoulos D et al. Acute and Chronic Paronychia. Am Fam Physician 2008; 77(3)
• (2) Clark DC. Common acute hand infections. Am Fam Physician. 2003;68(11):2167-76
• (3) Rockwell PG. Acute and chronic paronychia. Am Fam Physician. 2001;63(6):1113-6
• (4) Lee HE et al. Acute paronychia heralding the exacerbation of pemphigus vulgaris. Int J Clin Pract. 2004;58(12):1174-6.