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HIV. EPIDEMIOLOGY AND BIOLOGY OF HIV: The acquired immunodeficiency syndrome (AIDS) was first recognised in 1981. It is caused by the human immunodeficiency virus (HIV-1). HIV-2 causes a similar illness to HIV-1 but is less aggressive and restricted mainly to western Africa.
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EPIDEMIOLOGY AND BIOLOGY OF HIV: • The acquired immunodeficiency syndrome (AIDS) was first recognised in 1981. It is caused by the human immunodeficiency virus (HIV-1). HIV-2 causes a similar illness to HIV-1 but is less aggressive and restricted mainly to western Africa.
Immune deficiency is a consequence of continuous high-level HIV replication leading to virus and immune-mediated destruction of the key immune effector cell, the CD4 lymphocyte.
PREVENTION MEASURES FOR HIV TRANSMISSION Sexual • Comprehensive sex education programmes in schools • Public awareness campaigns for HIV • Easily accessible/discreet testing centres • Safe sex practices (avoiding penetrative intercourse, delaying sexual debut, condom use, fewer sexual partners) • Targeting safe sex methods to high-risk groups • Control of STIs • Effective treatment of HIV-infected persons • Post-sexual exposure prophylaxis
Parenteral • Blood product transmission (donor questionnaire, routine screening of donated blood, blood substitute use) • Injection drug use (education, needle/syringe exchange, avoidance of 'shooting galleries', sharing and support for methadone maintenance programmes)
Perinatal • Routine antenatal HIV antibody testing • Counselling about planning/risks of pregnancy if HIV-seropositive • Measures to reduce vertical transmission
CLASSIFICATION OF HIV and NATURAL HISTORY • Primary infection • Asymptomatic infection • Mildly symptomatic disease(ARC) • AIDS
1)Primary infection • Primary infection is symptomatic in 70-80% of cases and usually occurs 2-6 weeks after exposure. • CLINICAL FEATURES OF PRIMARY INFECTION • Fever with rash • Pharyngitis with cervical lymphadenopathy • Myalgia/arthralgia • Headache • Mucosal ulceration
Primary infection(cont) • Symptomatic recovery occurs after 1-2 weeks but occasionally may take up to 10 weeks • Diagnosis is made by detecting HIV-RNA in the serum or by immunoblot assay (which shows antibodies developing to early proteins). • The differential diagnosis of primary HIV includes acute Epstein-Barr virus (EBV), cytomegalovirus (CMV), streptococcal pharyngitis, toxoplasmosis and secondary syphilis.
2)Asymptomatic infection • Asymptomatic infection follows and lasts for a variable period, during which the infected individual remains well with no evidence of disease except for the possible presence of persistent generalisedlymphadenopathy (PGL, defined as enlarged glands at ≥ 2 extra-inguinal sites).
3)Mildly symptomatic disease • Mildly symptomatic disease (CDC Classification category B disease) then develops in the majority, indicating some impairment of the cellular immune system. These diseases correspond to AIDS-related complex (ARC) conditions but by definition are not AIDS-defining (Box 14.5). The median interval from infection to the development of symptoms is around 7-10 years,
Mildly symptomatic disease(cont) HIV MILDLY SYMPTOMATIC DISEASES • Oral hairy leucoplakia • Recurrent oropharyngealcandidiasis • Recurrent vaginal candidiasis • Severe pelvic inflammatory disease • Bacillary angiomatosis • Cervical dysplasia • Idiopathic thrombocytopenic purpura • Weight loss* • Chronic diarrhoea* • Herpes zoster • Peripheral neuropathy • Low-grade fever/night sweats*
4)Acquired immunodeficiency syndrome (AIDS) • AIDS (CDC Classification category C disease) is defined by the development of specified opportunistic infections, tumours etc.
Acquired immunodeficiency syndrome (AIDS) cont • AIDS-DEFINING DISEASES Oesophagealcandidiasis • Cryptococcal meningitis • Chronic cryptosporidialdiarrhoea • CMV retinitis or colitis • Chronic mucocutaneous herpes simplex • Disseminated Mycobacterium aviumintracellulare • Pulmonary or extrapulmonary tuberculosis • Pneumocystiscarinii (jirovecii) pneumonia • Progressive multifocal leucoencephalopathy • Recurrent non-typhiSalmonellasepticaemia • Cerebral toxoplasmosis • Extrapulmonarycoccidioidomycosis • Invasive cervical cancer • Extrapulmonaryhistoplasmosis • Kaposi's sarcoma • Non-Hodgkin lymphoma • Primary cerebral lymphoma • HIV-associated wasting • HIV-associated dementia
PRESENTING PROBLEMS IN HIV INFECTION (MUCOCUTANEOUS DISEASE) • Mucocutaneous manifestations are common in HIV . • Most patients are affected at some time and for many it is a major problem • Dermatological problems may present atypically, coexist with other pathologies and be harder to manage than in an HIV-negative person.
cont • Type and severity of rash are often dependent upon the level of CD4 count. • The presence of either oropharyngealcandidiasis or oral hairy leucoplakia in a young person is suggestive of HIV infection.
SPECIFIC SKIN CONDITIONS Fungal infections • Early HIV-associated skin diseases include xerosis with pruritus, seborrhoeic dermatitis, and an itchy folliculitic rash which may be fungal (Malasseziafurfur), staphylococcal or eosinophilic in aetiology • Dermatophyte infection affecting skin (feet, body, face) and nails is also common, and may be extensive and difficult to treat.
Seborrhoeic dermatitis is very common in HIV and is present in up to 80% of patients with AIDS; severity increases as the CD4 count falls. It presents as dry scaly red patches on the face (typically on the cheeks, in the nasolabial folds, around the eyebrows, behind the ears and on the scalp). The cause is multifactorial but Malasseziafurfur is important.
Viral infections : • The major viral infections affecting the skin are herpes simplex, varicella zoster (VZV), human papillomavirus (HPV) and molluscumcontagiosum. • Herpes simplex (type 1 or 2) may affect the lips, mouth, skin or anogenital area and is seen in 20% of cases. In later-stage HIV, the lesions are usually chronic, extensive, harder to treat and recurrent (Fig. 14.3). Persistent and severe anogenital ulceration is usually herpetic and a marker for underlying HIV.
Varicella zoster usually presents with a dermatomal vesicular rash on an erythematous base and may be the first clue to a diagnosis of HIV infection. It can occur at any stage but is more frequent with failing immunity. In patients with a low CD4 count (< 100 cells/mm3) the rash may be more severe, multidermatomal, persistent or recurrent, or may become disseminated. Involvement of the trigeminal nerve, scarring on recovery and associated motor defects are probably also more common
Old herpes zoster and Kaposi sarcoma in a patient with HIV disease
Human papillomavirusinfection is frequent amongst HIV patients and is usually anogenital. • Lesions are on feet and hands (especillyperiungual) • Both oncogenic and non oncogenic • Improvement on HAART
MOLLUSCUM CONTAGIOSUM is an epidermal pox virus infection • 10% of AIDS pt • Lesions are 2-5 mm in diameter papules with central umblicus . • Mostly affects the face ,scalp and genital region. • With improvement in CD4 counts lesions disappears
Young man with HIV disease and molluscumcontagiosum on the lateral part of the eyebrow.
BACTERIAL AND PARASITIC INFECTIONS • Bacterial infections includes • Staph aureus(folliculitis,cellulitis,abscessess) • Bacillayangiomatosis(this infection is due to cat-scratch bacillus ,bartonellahenselae • Syphilis(primary and secondary ) • Scabies(intense pruritic,encrusted papules affecting web spaces ,wrists,peri-umblical area, buttocks and sides of feet. Remember that in case of HIV scabies face and neck are uniquely affected .
SPECIFIC ORAL CONDITIONS • CANDIDIASIS>candida infection is exclusively mucosal (White patches on buccal mucosa that can be scraped off to reveal a red raw surface)and present in every HIV affected patient in which CD4 count is below 200 cells/mm3 . • Less common is erythmatouscandidiasis(sore mouth ,reddendmucosa,smooth shiny toungue . • Hypertrophic candidiais(leukoplakia –like lesion which do not scrap off but respond to anti fungal tretment ) is also less common . • Candida oesophagitis may be present
Oral hairy leukoplakia • It has apperarsnce of white plagues running vertically on the sides of toungue . • It is assymptomatic and do not require any treatment • High dose aciclovir is good in eradicating but relapse is observed
Kaposi sarcoma :a hallmark of AIDS FEATURES Cutaneous • Purple non-tender, non-pruritic papules • May ulcerate on feet • Often associated with oedema and lymphadenopathy • Crease line arrangements • Favoured sites: nose, genitals, lower limbs Oral • Favoured sites: palate, gum margins, fauces (Fig. 14.13) • Predictor of gastrointestinal and respiratory tract disease Visceral • Pulmonary, pleural effusion • Gastrointestinal tract • Hepatosplenomegaly • Ocular
INVESTIGATIONS AND MANAGEMENT IN SKIN MENIFESTATION OF HIV • Diagnosis in mucocutaneous conditions in HIV including KAPOSi s sarcoma is usually clinical . • Rarely baterial ,fungal or viral cultures are necessary. but • Any person with an unusual rash ,which is unreponsive to topical anti fungal or topical steroids combinations or CD4 <50 cells/mm3 requires skin biopsy for histology and culture .
FIRST LINE TREATMENT IN HIV RELATED MUCOCUTANEOUS CONDISTIONS