Bacterial, Viral, Fungal, and Parasitic Infections in HIV Disease and AIDS

New insights into HIV-1-primary skin disorders

Since the first reports of AIDS, skin involvement has become a burdensome stigma for seropositive patients and a challenging task for dermatologist and infectious disease specialists due to the severe and recalcitrant nature of the conditions. Dermatologic manifestations in AIDS patients act as markers of disease progression, a fact that enhances the importance of understanding their pathogenesis.

Broadly, cutaneous disorders associated with HIV type-1 infection can be classified as primary and secondary. While the pathogenesis of secondary complications, such as opportunistic infections and skin tumours, is directly correlated with a decline in the CD4⁺ T cell count, the origin of the certain manifestations primarily associated with the retroviral infection itself still remains under investigation.

The focus of this review is to highlight the immunological phenomena that occur in the skin of HIV-1-seropositive patients, which ultimately lead to skin disorders, such as seborrhoeic dermatitis, atopic dermatitis, psoriasis and eosinophilic folliculitis. Furthermore, we compile the latest data on how shifts in the cytokines milieu, impairments of the innate immune compartment, reactions to xenobiotics and autoimmunity are causative agents in HIV-1-driven skin diseases. Additionally, we provide a thorough analysis of the small animal models currently used to study HIV-1-associated skin complications, centering on transgenic rodent models, which unfortunately, have not been able to fully unveil the role of HIV-1 genes in the pathogenesis of their primarily associated dermatological manifestations.

Skin Disease in HIV-Positive Persons Living in Puerto Rico

OBJECTIVES

To determine the frequency of skin disease in persons infected with the human immunodeficiency virus (HIV), to validate the agreement of self-reported skin condition(s) versus objective data obtained by physical examination, and to describe the characteristics of HIV-positive persons with skin disease in Puerto Rico.

DESIGN

Descriptive correlational design.

SETTING AND PARTICIPANTS

Ninety-five HIV-positive adults in San Juan, Puerto Rico. Ninety-five adults who were HIV-positive participated.

RESULTS

Ninety (94.7%) participants had skin disease and/or signs or symptoms suggestive of disease. Diseases most often reported were onychomycosis (n=16; 17.8%) and nongenital warts (n=11; 12.2%). Signs and symptoms reported were dryness (n=59; 65.6%), itch (n=58; 64.4%), erythema (n=30; 33.3%), induration (n=13; 14.4%), postinflammatory hyperpigmentation (n=9; 10.0%), and excoriation (n=9; 10.0%). Kappa index confirmed the relationship between self-reported skin condition or signs and symptoms and the diagnosis of a skin disease by the physician (k=.42). Positive predictive value was 97.7% (95% confidence interval [CI], 94.7%-100%). Condyloma acuminata was associated with male gender (chi2=4.09, P=.043). Tinea pedis (P=.0215), excoriations (P=.002), and prurigo nodularis (P=.0096) were associated with having a low CD4 cell count.

CONCLUSIONS

This study shows that persons infected with HIV can identify significant skin manifestations that are associated with the diagnosis of a skin disease. This validates the use of self-reporting of skin conditions in these patients and points to the importance of educating patients and providers to report patient skin problems. Although the high prevalence of skin disease found in this study population supports a need for improving dermatologic care in HIV-infected patients, the findings of such prevalent cutaneous disease can also provide caretakers with ample evidence to suspect and, therefore, test for HIV infection.

Bacterial infections: uncommon presentations

The essence of dermatology is morphology. The most important instrument in the practice of dermatology has always been, and still is, the naked eye; however, "We see only what we are ready to see, what we have been taught to see" (Jean Martin Charcot). Although most practitioners will easily correctly diagnose common bacterial skin diseases (such as cellulitis, erysipelas, impetigo, etc), only a trained and updated dermatologist will recognize the unusual forms and rare variants of these diseases. Bacterial skin diseases are sometimes acute and life-threatening. The mortality rates from necrotizing fasciitis range from 20% to 40%, to name just one example. It is not unreasonable to expect that dermatologists, whether in clinical practice or in referral centers, will be the first physicians to be confronted with unusual variants of bacterial skin diseases that have been unrecognized by non-dermatologists. Some of these cases might even be life-threatening, and only prompt and early recognition, diagnosis, and treatment can make the difference between losing and saving a patient's life. In short, we dermatologists should hone our clinical diagnostic skills and expand our knowledge of the rare forms and unusual and atypical variants of skin diseases: the textbook variants will probably be recognized and treated by general practitioners.

Diagnosis and treatment of infectious diseases in HIV-infected hosts

Treatment of infectious diseases in patients with HIV infection is of primary importance in patient care. Viral, bacterial, parasitic, and fungal pathogens all may affect these patients. It is essential that accurate diagnoses be made and appropriate therapy be administered as early as possible.

Fungal infections in patients with acquired immunodeficiency syndrome

The incidence and severity of fungal infections appear to increase with progression of HIV disease. Because of the significant morbidity and mortality associated with the mycoses discussed, knowledge of the clinical syndromes, early diagnosis, and prompt institution of therapy are crucial for a favorable outcome. For disseminated or invasive fungal infections, suppressive therapy must be continued to prevent relapse.

Management of common superficial fungal infections in patients with AIDS

Cutaneous fungal infections are a major source of morbidity in HIV-infected patients, and their management poses special challenges. Superficial mycoses, such as tinea pedis, tinea cruris, tinea corporis, and onychomycosis, are no more common in HIV-infected patients than in the HIV-negative population but are of greater severity. Although they respond to topical and systemic antifungal agents, HIV-positive patients are predisposed to frequent recurrences. Unusual types of fungal infections such as Majocchi's granuloma are more likely to develop in HIV-infected patients and respond best to systemic antifungal therapy with imidazoles or triazoles. Infections with Candida albicans develop in virtually all HIV-positive patients. Although mucosal involvement is the most common, patients may also develop superficial cutaneous infections. Topical agents are frequently all that is necessary, but in some, oral medications are required. Although fluconazole is effective, an appreciable number of isolates are resistant. Patients with pityriasis versicolor and seborrheic dermatitis, in which Pityrosporum species are thought to be involved, respond well to short courses of oral ketoconazole. Milder forms of seborrheic dermatitis can also be treated with low-potency topical steroids or topical ketoconazole. The oral triazole fluconazole is not particularly effective in the management of seborrheic dermatitis. Although the cause of eosinophilic pustular folliculitis, a common disorder in immunosuppressed HIV-positive patients, is unknown, some can be cured with high doses of itraconazole, suggesting that fungi are important in the pathogenesis of the disease in some patients.