portal of entry for the organisms concerned, usually staphylococci, is a break
in the skin or cuticle as a result of minor trauma. The subsequ-ent acute
inflammation, often with the formation of pus in the nail fold or under the
nail, requires systemic treatment with flucloxacillin or erythro-mycin and appropriate surgical drainage.
combination of circumstances can allow a mixture of opportunistic pathogens
(yeasts, Gram-positive cocci and Gram-negative rods) to colonize the space
between the nail fold and nail plate. Predisposing fac-tors include a poor
peripheral circulation, wet work, working with flour, diabetes, vaginal
candidosis and overvigorous cutting back of the cuticles.
nail folds become tender and swollen (Figs 13.26 and 13.28) and small amounts
of pus are discharged at intervals. The cuticular seal is damaged and the
adjacent nail plate becomes ridged and discoloured. The condition may last for
In atypical cases, consider the outside chance of an amelanotic melanoma. Paronychia should not be con-fused with a dermatophyte infection in which the nail folds are not primarily affected.
Test the urine for sugar, check for vaginal candidosis.
should be cultured.
of the cuticle should cease. The hands should be kept as warm and as dry as
possible, and the damaged nail folds packed several times a day with an
imidazole cream. If there is no response, and swabs confirm that candida is
present, a 2-week course of itraconazole should be considered.
common dermatophytes that cause tinea pedis can also invade the nails.
infection is common and associated with tinea pedis. The early changes occur at
the free edge of the nail and spread proximally. The nail plate becomes yellow,
crumbly and thickened. Usually only a few nails are infected but occasionally
all are. The fingernails are involved less often and the changes, in contrast
to those of psoriasis, are usually confined to one hand.
condition seldom clears spontaneously.
has been mentioned. Yeast infections of the nail plate, much more rare than
dermatophyte infec-tions, can look similar. Coexisting tinea pedis favours
dermatophyte infection of the nail.
examination of a nail clipping is a simple procedure. Cultures should be
carried out in a mycology laboratory.
that most symptom-free fungal infections of the toenails need no treatment at
Peri-ungual warts are common and stubborn. Cryo-therapy must be used carefully to avoid damage to the nail matrix. It is painful but effective.
fibromas (see Fig. 21.5) arise from thenail folds, usually in late
childhood, in patients with tuberous sclerosis.
tumours can occur beneath the nail plate.The small red or bluish
lesions are exquisitely painful if touched and when the temperature changes.
Treat-ment is surgical.
exostoses (Fig. 13.22) protrude painfullyunder the nail plate. Usually
secondary to trauma to the terminal phalanx, the bony abnormality can be seen
on X-ray and treatment is surgical.
cysts (Fig. 13.29) occur on the proximalnail folds, usually of the
fingers. The smooth domed swelling contains a clear jelly-like material that
tran-silluminates well. A groove may form on the adjacent nail plate.
Cryotherapy, injections of triamcinolone and surgical excision all have their
Malignant melanoma should be suspected in any subungual pigmented lesion, particularly if the pigment spreads to the surrounding skin. Subungual haematomas may cause confusion but ‘grow out’ with the nail (Fig. 13.21). The risk of misdiagnosis is high-est with an amelanotic melanoma, which may mimic chronic paronychia or a pyogenic granuloma.