A Guide To Lower Extremity Cutaneous Manifestations In Patients With HIV Infections
When Allergic Contact Dermatitis Occurs
Contact dermatitis is exceedingly common in the U.S. It is one of the top ten causes for patient visits to their primary care physicians.21 Shoe dermatitis is a common type of contact dermatitis. Shoe dermatitis is caused by contact of the foot with shoes or the chemicals used during the manufacturing and finishing of shoes. Rubber remains a common cause of shoe dermatitis, especially with such preservative antioxidants as monobenzyl-hydroquinone.
Once you have confirmed the diagnosis of shoe dermatitis, treatment management goals include alleviation of pruritus and resolving inflammation.
Curr and Nixon describe a 41-year-old HIV-positive man, who presented with a two-month history of a generalized pruritic rash, which had started on his feet.22 Using patch testing, the authors diagnosed allergic contact dermatitis to the textile dye basic red 46, which was likely present in the patient’s dark-blue-colored socks. They achieved complete resolution of his symptoms with avoidance of these socks, a topical steroid ointment and emollient cream.
What About Cutaneous Manifestations Caused By Medications For HIV?
Luther and Glesby published a summary that looked at a significant number of patients with skin pathology, some of which can be attributed directly or indirectly to antiretroviral therapy.23 This published report recounts that non-nucleoside reverse transcriptase inhibitors exhibit a class effect with regard to skin adverse manifestation and the spectrum of disease can vary from mild morbilliform rash to Stevens-Johnson Syndrome.2,3,23 Also bear in mind that some protease inhibitors have been implicated in causing rash while indinavir causes retinoid-like manifestations such as paronychia, ingrown toenails, alopecia and curling of straight hair.3,23
Zidouvudine has become one of the standard medications used in HARRT therapy for patients with AIDS and for those with asymptomatic HIV infection. One of the interesting side effects of using zidovudine is alterations in nail pigmentation, which occur primarily in African-American patients. Rahav and Maayan describe a case report of progressive pigmentation of both fingernails and toenails in a Caucasian patient.24
The degree of hyperpigmentation of the nails and skin is related to the dosage of azidothymidine (AZT). Patients note a decrease in hyperpigmentation when the dose is decreased and the pigmentation clears if the drug is discontinued. This hyperpigmentation appears to be related to increased melanogenesis in the areas of hyperpigmentation and not drug deposition.
Paronychia: Is It A Common Side Effect Of HIV Medications?
A review of the literature reveals case reports and retrospective cohort accounts of patients receiving antiretroviral therapy for HIV infection and the subsequent development of paronychias.25-34
Zerboni and colleagues reported the onset of paronychia in 12 HIV-positive patients who were receiving lamivudine during a three-month period.25 The clinical presentation of paronychia involved one great toe in five patients, both great toes in five patients, and fingernails as well as toenails in two patients.25,29,33 Further, these patients did not have any risk factors for paronychia development.
Bouscarat and co-workers described 42 HIV-positive individuals who presented with great toe paronychia secondary to ingrown nails and they had received the HIV treatment indinavir.26,29,33 These patients had no prior episodes of paronychia, psoriasis or local trauma.26 The medium time of onset for drug-induced ingrown toenails was 120 days.26 These authors suggest that inhibition of endogenous proteases may be the explanation for initial hypertrophy of the nail fold and the subsequent development of similar lesions of pyogenic granuloma.26,29