HIV refers to the human immunodeficiency virus, which is a lentivirus (a subgroup of retrovirus family) that infects humans. The mode of infection is mainly through contact with infected body fluids (such as blood, semen, pre-ejaculate, vaginal fluid, and breast milk). Over time, HIV destroys the immune system and renders the infected individual incapable of warding off various opportunistic infections and cancers. Eventually, HIV infection leads to acquired immunodeficiency syndrome (AIDS). People with AIDS die from a host of life-threatening infections and cancers that their body can no longer resist.
Skin problems can occur in anybody. However, people suffering from HIV infection are especially prone to acquiring infections, including skin infections. Some skin infections are rare among the general population but frequently seen in HIV-infected individuals. This is because a healthy immune system usually fends off these infections, but the weakened immune system in HIV-infected individuals is not able to do so.
Apart weakening of the immune system, HIV infection can affect the skin in various ways that increases the risk of skin infections and rashes. The skin may become excessively dry (technically known as xeroderma) and itchy (technically known as pruritis). HIV-infected individuals are also prone to get drug-induced allergies, accompanied by an itchy skin rash. Psoriasis, folliculitis, acne, and seborrheic dermatitis are also prevalent in the HIV-infected population.
Read more on HIV infection and AIDS.
Types of HIV-related skin infections and rashes
The following are some of the skin conditions that are especially found in HIV infected individuals:
Dermatomycosis is a common fungal skin infection observed in HIV-infected individuals. The fungi, Malassezia furfur (also known as Pitysporum ovale), is the most common cause of dermatomycosis. However, it is not the only cause, and a variety of other yeasts and molds may also be responsible for the infection. Dermatomycosis mostly affects the skin on face, chest, hands and legs. The skin on other parts of the body may also be affected. Folluculitis and secondary infections in seborrheic dermatitis may also be a result of dermatomycosis.
Impetigo is a bacterial skin infection caused by Staphylococcus aureus and Streptococcus pyogenes. It is characterized by skin lesions, itchy rashes, fluid-filled blisters and red sores. Impetigo infection is facilitated by breaks in the skin such as those caused by insect bites, animal bites, injuries, and scratching-induced micro-tears. It is also contagious, and spreads via skin-to-skin contact or skin contact with objects that an infected person has used (such as towels and beddings). HIV-infected individuals are especially prone to impetigo due to their weakened immunity. Xeroderma or excessively dry skin in these individuals further increases their susceptibility.
Herpes is an infection caused by the herpes simplex viruses: HSV-1 and HSV-2. The most common body parts affected by herpes include the mouth and the genital regions. Herpes infection on the mouth is characterized by ulcers on the lips, a condition that is also called cold sores (or herpes labialis). HSV-1 is the cause of oral herpes, whereas HSV-2 is the cause of genital herpes outbreaks. Herpes infections may also affect other regions of the body. In HIV-infected individuals, the genital herpes infection may spread to the region around the anus (perianal region) and the rectum. In these individuals, herpes may also affect the oral cavity, resulting in a condition known as mucocutaneous herpes.
The varicella zoster virus causes chicken pox, which is a common childhood disease. People who recover from chicken pox develop immunity against it. However, they still have the virus inside them. This virus may get reactivated later in life, causing a disease known as shingles or herpes zoster. Chickenpox and shingles are frequently seen in HIV-infected adults.
Human papillomavirus (HPV)
Human papillomavirus (HPV) has a variety of different strains. Most of them affect the genital areas. HPV infections are characterized by skin warts. These warts are very common in HIV-infected individuals. HPV warts are seen in various parts of the body, but are particularly persistent in the anal, genital, and finger regions. In healthy individuals, the immune system naturally clears HPV infection in most cases. However, the weakened immune system of HIV-infected individuals makes them vulnerable to persistent HPV infections and warts.
Scabies are caused by an allergic skin reaction to mites (technically called Sarcoptes scabiei). These mites burrow inside the skin and lay their eggs. Even when the mites are treated away, the eggs and feces they leave behind can irritate the skin and produce allergic reactions. The most common skin areas that get affected by scabies are the regions between fingers and toes, abdomen and buttocks. In HIV-infected individuals, the infection may also spread to the skin on face and neck. Thick yellow lesions (also called Norway scabies) are a typical presentation of scabies in HIV-infected individuals.
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Syphilis is a bacterial infection caused by Treponema pallidum. It is a sexually transmitted disease. The signs and symptoms of syphilis develop in stages that are spread across many years. The first stage after infection is characterized by the presence of painless sores (also known as chancre) on mouth, genitals and rectum. These sores heal and a skin rash develops all over the body, including areas on the soles of feet and the palms of hands. This skin rash also heals. The third stage of infection occurs years later, and involves extensive damage to heart, brain, nerves and eyes.
Kaposi’s sarcoma is a very rare skin cancer in the general population. However, it is comparatively more frequent in the HIV-infected population. In fact, Kaposi’s sarcoma is an AIDS-defining condition. Kaposi’s sarcoma is caused by human herpes virus type-8 (abbreviated as HHV8). The typical presentation is a skin rash that is red, blue, purple or dark brown in color.
Molluscum contagiosum is a viral skin infection. It is characterized by small, skin-colored, raised lesions (called papules) that have a small depression at their apical ends. These lesions are usually between 2-5 millimeters in diameter. However, they can even grow to very large sizes.