Retronychia a little‐known cause of paronychia: A report of two cases in adolescent patients

Abstract

Retronychia is a clinical condition resulting from embedding of the nail plate into the proximal nail fold. We report two adolescent girls, 14 and 16 years of age, with a history of chronic proximal paronychia of the great toe, one of them developing osteomyelitis. After failure of treatment with several systemic antibiotics, nail avulsion was performed, leading us to the diagnosis of retronychia and with rapid and complete resolution of symptoms in both cases. Delay in diagnosis of retronychia can lead to local complications and prolonged discomfort.

Treatment of retronychia: A systematic review and suggested treatment algorithm

“…6,[11][12][13] The main triggers of retronychia reported in the surgical group were, in decreasing order: trauma (21.6%), 1,2,5,6,[13][14][15][16][17][18] sport (18.9%) 1,2,16,[18][19][20] and tight footwear (13.5%) 2,14,18,21,22 ; vice-versa the same factors were reported with an increased prevalence and opposite order in the medical group: trauma (17.3%), 1,18 sport (26.7%), 2,12,18,23,24 tight footwear (44%), 2,12,18,23,24 respectively. The most reported clinical signs of retronychia were: paronychia, periungual discharge, 13,15,16,21,25,26 yellowish discoloration of the nail plate (xanthonychia), 11,[13][14][15][16]…”

“…The main triggers of retronychia reported in the surgical group were, in decreasing order: trauma (21.6%), 1,2,5,6,13–18 sport (18.9%) 1,2,16,18–20 and tight footwear (13.5%) 2,14,18,21,22 ; vice‐versa the same factors were reported with an increased prevalence and opposite order in the medical group: trauma (17.3%), 1,18 sport (26.7%), 2,12,18,23,24 tight footwear (44%), 2,12,18,23,24 respectively. The most reported clinical signs of retronychia were: paronychia, periungual discharge, 13,15,16,21,25,26 yellowish discoloration of the nail plate (xanthonychia), 11,13–17,19,22–27 granulation tissue formation, 1,14–16,20,22–24 subungual hemorrhage, 24 back and forth mobility of the overlying nail plate 14,16,17,19,22 and distal onycholysis promoting bed retraction and raising of the distal pulp 6,13,14,16,23,24,27 (Table 2).…”

Classification of Retronychia: A Narrative Clinical Review

“…Pain intensity is subject dependent and not necessarily correlated with the intensity of inflammation. Very severe cases may present with exuberant pyogenic granuloma formation, fistulae or the nail can even pierce through the PNF [17,18]. However, some authors have put forward the term chronic noninflammatory retronychia, by noticing severe dystrophic nail lamellae being shed and discrete to absent PNF inflammation.…”

Retronychia as a cause of opportunistic nail infections

“…Our patient showed an unexpected worsening of the clinical picture after the treatment prescribed for P. aeruginosa superinfection. Although bacterial superinfection of retronychia has been rarely reported, one case documented bone involvement by P. aeruginosa 4 . Indeed, onycholysis and granulation tissue at the PNF may be an ideal medium for opportunistic bacteria and fungi.…”