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Manifestations
of HIV disease The HIV virus causes a chronic infection that leads to profound immuno-suppression. The course of the infection may vary with some individuals developing immunodeficiency with 2 to 3 years and others remaining AIDS free for 10-15 years. Eventually the infected individual develops Early symptomatic HIV, which progresses to AIDS with associated opportunistic infections and malignancies. The manifestations of infections in
AIDS patients depend on the level of immunity, which is reflected by
the CD4+ T cell count. The majority of the infections occur when the
CD4 cell count falls below 500 cells/mm³. These include
pneumoccocal and other pneumonia, pulmonary tuberculosis, Herpes
Zoster, candidisis, Kaposi's sarcoma, cryptosporidiosis, Oral hairy
leukoplakia.
Opportunistic Infections are important part of the HIV disease process. It is common to find AIDS patients with multiple OIs. These OIs result in more rapid decline in CD4 T-cell count than the decline resulting from HIV disease itself. Thus effective therapy is required to treat and prevent these infection. The incidence and type of OIs in HIV patients is directly related to the CD4 count in that individual. Common OIs are Tuberculosis both pulmonary and extra-pulmonary , Oropharyngeal candidiasis, Herpes zoster, Herpes simplex, Toxoplasmosis, Cryptococcal Meningitis, Pneumocystitis carini pneumonia, Cytomegalovirus retinitis, Cryptosporidial diarrhea. Tuberculosis It ranks one of the most common opportunistic infections. TB can occur in early stage HIV patients with CD4 cell count < 300 cells/mm³. Clinical presentation is usually similar to that in non-HIV patients. Typical symptoms include productive cough of several week's duration, fever, weight loss, night sweats and haemoptysis. In patients with advanced HIV disease extra-pulmonary disease is more common. Disseminated disease with involvement of bone marrow, bone, urinary and gastrointestinal tract, liver, regional lymph nodes, and central nervous system is common. Tuberculosis in HIV patients may show atypical findings in the chest x-ray, negative tuberculin reaction, and extra pulmonary lesions. Management of HIV related tuberculosis is complicated as there is significant interaction between antiretroviral therapy and standard anti-TB medication. Mycobacterium Avium Complex (MAC) FUNGAL INFECTIONS Fungal Infections are one of the commonest causes of mortality and morbidity in HIV patients. Majority of the patients go down hill because of these infections and they prove to be the cause of death. Candidiasis is one of the commonest fungal infection seen in HIV patients. Other fungal infection are Cryptococcal meningitis, Histoplasmposis, and Pneumocystis carinii pneumonia (PCP) Candidiasis Oral candidiasis is extremely common in AIDS patients. The most common pathogen is Candidia albicans. Other pathogens are C.glabrata, C.krusei and C.parapsilosis. Most commonly the presentation is Oropharyngeal Candidiasis - in this both the moth cavity and the pharynx is involved. It generally presents as burning pain, altered taste sensation and difficulty in swallowing liquids and solids. Painless white patches are found on the tounge, gums, buccal mucosa, tonsils and pharynx. Oesophageal candidiasis is diagnosed when dysphagia is present with thrush. Anti fungal therapy has to be given.
Cryptococcosis The most common manifestation fo cryptococcosis is meningitis. It is caused by Cryptoccocus neoformans. Common presenting symptoms are severe headache, fever, progressive malaise, nausea, fatigue, loss of appetite and altered mental status. Typical clinical signs of meningitis may not be seen in such patients. It is treated with Amphotericin B and Flucytosine. such patients may need to be put on life long oral fluconazole. Pneumocystis carinii pneumonia (PCP) This infection in HIv patients presentas Fever tachypnoea and dry cough. Trimethoprim-sulphamethoxazole orally is effective for this condition. Its dose is 2 tab given 8 hrly for 2-3 wks. Such patients have to be put on prophylaxis against PCP with one tab of this medication every day. VIRAL INFECTIONS Common viral infection in HIV patients are Herpes zoster, Genital herpes, Herpes labialis and CMV retinitis. Most of the episodes of genital and herpes labialis are thought to be reactivation of the latent infection. Treatment for this include Acyclovir 200-400 mg 5 times daily for 10-14 days. For prevention continuous therapy may have to be given. Primary infection with varicella zoster virus leads to severe chicken pox in HIV patients. Herpes zoster tend to occur within months of the primary infection rather than years after the primary infection in case of non-HIV individuals. Oral acyclovir is the preffered therapy. Cytomegalovirus disease Retinitis is the most common manifestation of the CMV infection in the HIV patients. The symptoms include light flashes, floaters, loss of central and peripheral visual fields and blurred vision. Ganciclovir is used in this condition. PROTOZOAN INFECTIONS Toxoplasmosis is caused by toxoplasma gondii. Most common manifestation is encephalitis. It presents with severe headache, focal neurological deficits, fever, confusion. Diagnosis is made with CNS masses on CT or MRI scans and positive toxoplasma serology. Treatment include Sulphadiazine, pyrimethamine, folic acid. AIDS ASSOCIATED DIARRHEA Diarrhea is the most common Gastro intestinal complication in people who are infected with HIV. It can be caused by bacteria like salmonella, shigella, camphylobacter. Parasites like cryptosporidium, isospora, giardia, microsporidia. Mycobacterium tuberculosis, MAC. Viral - cytomegalovirus. Diarrhea may also occur due to side effects of the drugs like protease inhibitors.
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