The human immunodeficiency virus (HIV) targets and destroys CD4 T-cells, the immune system’s primary coordinators, leading to acquired immunodeficiency syndrome (AIDS). This progressive compromise of the body’s defenses allows a wide range of conditions to take hold, many of which first appear on the skin or mucous membranes. Dermatological and mucosal lesions are extremely common, affecting approximately 90% of individuals with HIV. The appearance of these skin changes often serves as an important clinical indicator, alerting healthcare providers to the presence of underlying immunodeficiency or the progression toward advanced disease.
Classifying the Causes of Lesions
The appearance of lesions is directly related to the decline in the CD4 T-cell count, which dictates the severity of the immune suppression. As the CD4 count drops, the body loses the ability to manage common pathogens and control abnormal cell growth, resulting in three major categories of skin and mucosal issues. The largest group is infectious lesions, which arise from organisms that seize the opportunity of a weakened immune system to multiply and cause disease. Fungal infections are frequent, notably candidiasis (thrush), which is caused by Candida yeast and is often one of the earliest signs of immune decline.
Viral infections also manifest aggressively in the setting of low CD4 counts, often presenting as severe or recurrent outbreaks. The herpes simplex virus (HSV), which causes cold sores and genital lesions, may produce large, chronic, non-healing ulcers that persist for months. Similarly, the poxvirus that causes molluscum contagiosum results in numerous, widespread bumps across the body, a presentation rarely seen in immunocompetent individuals. Even common skin bacteria, such as Staphylococcus and Streptococcus, can cause more severe and deep-seated infections, including recurrent folliculitis, which is inflammation of the hair follicles.
A second category involves malignant lesions, which include cancers that the suppressed immune system fails to detect and eliminate. Kaposi’s Sarcoma (KS) is the most notable and is an AIDS-defining illness. This vascular cancer is caused by the Human Herpesvirus-8 (HHV-8) and is directly linked to the level of immune suppression. Other malignancies, such as cutaneous Non-Hodgkin Lymphoma and an increased incidence of basal cell and squamous cell carcinomas, are also more prevalent and aggressive in people with advanced HIV.
The final group consists of inflammatory and dermatological lesions, which are not caused by opportunistic infection or cancer but are exacerbated by underlying immune dysregulation. Seborrheic dermatitis, characterized by scaly, greasy patches, is one of the most common skin conditions in this population and can be unusually severe and extensive. Another example is pruritic papular eruption (PPE), which causes intensely itchy, widespread bumps, often appearing when the CD4 count is significantly low.
Identifying Common Manifestations and Locations
Oral manifestations are particularly common and often appear early in the disease course. Oral candidiasis, or thrush, is recognizable as creamy white patches on the tongue, inner cheeks, or roof of the mouth that can usually be scraped away, sometimes revealing red, raw tissue underneath.
Oral Kaposi’s Sarcoma lesions typically appear as flat or slightly raised patches that are purple, red, or brown in color, frequently found on the gums or the hard palate. Another common finding is oral hairy leukoplakia, which presents as white, corrugated or “hairy” patches on the sides of the tongue that cannot be easily rubbed off. These distinct appearances guide the healthcare provider in determining the specific pathology.
Cutaneous (skin) manifestations of Kaposi’s Sarcoma are usually seen as dark, firm lesions that can be brown, red, or purple, and they may be flat patches, raised plaques, or nodules. These lesions can appear anywhere on the body and may be mistaken for bruises, but they do not blanch when pressed. Molluscum contagiosum lesions are small, firm, dome-shaped bumps that often have a central indentation or “umbilication,” and in advanced HIV, they can be numerous, widespread, and unusually large.
Viral lesions like those from Herpes Simplex Virus present as clusters of small, painful, fluid-filled blisters (vesicles) on a red base, which then rupture to form crusts or chronic ulcers. Herpes Zoster, or shingles, is a reactivation of the chickenpox virus that creates a painful, blistering rash in a stripe or band, often confined to one side of the body. Internal manifestations are also a concern, as KS can spread to organs like the lungs or the gastrointestinal tract. Lesions in the lungs can cause shortness of breath, while lesions in the digestive tract may cause difficulty swallowing, abdominal pain, or internal bleeding.
Medical Approaches to Diagnosis and Treatment
A provider will first conduct a thorough physical examination to note the appearance, color, and location of the lesions. To confirm the specific cause, diagnostic methods include scraping a lesion for microscopic examination, such as a potassium hydroxide preparation for fungal infections, or swabbing for viral culture.
For malignant or atypical lesions, a biopsy is often necessary, where a small tissue sample is removed and analyzed under a microscope to confirm the presence of cancer cells or specific pathogens. The results of these tests, combined with the patient’s CD4 count and viral load, determine the most effective treatment course. The foundational treatment strategy for nearly all AIDS-related lesions is the initiation or optimization of highly active antiretroviral therapy (ART).
ART works by suppressing the HIV virus, which allows the CD4 T-cell count to rise and the immune system to recover its function. The goal of ART is to achieve an undetectable viral load, which is the most effective way to prevent the development of new opportunistic conditions.
While ART addresses the root cause, specific lesion management is often required to treat existing, severe, or painful lesions. For Kaposi’s Sarcoma, localized treatments such as cryotherapy (freezing), radiation therapy, or intralesional chemotherapy may be used to shrink or eliminate visible tumors. Fungal infections like candidiasis are treated with targeted topical or systemic antifungal medications. Viral outbreaks, such as those caused by HSV or Herpes Zoster, are managed with antiviral drugs to shorten the duration of the outbreak and reduce the risk of complications.