HIV INFECTION -Hiv Infection was discovered in 1981.
HIV TYPES;
- HIV-I infection
- HIV-II infection
Both viruses are trophic for CD-4 + Lymphocytes and have similar genetic structure. Both causes AIDS, but HIV-II apperas to be less commonlt transmitted vertically.
Side of spread:
- Sexual contact
- Through blood transfusion
- Maternal route
- Needle and syringe
Pathology:
HIV is single stranded RNA retrovirus from the lentivirus member of retrovirus family. After mucosal exposure, HIV is transported to the lymph nodes via dendritic CD4 or langerhans cells here infectional becomes established that faciliate capture and trnasport of HIV-I. Free or cell associated virus is then disseminated widely through the blood with seeding of sanctuar (eg CNS) and latent CD4 reservoirs. With times there is gradual attitude of the CD4 cell population resulting in increasing impairment of cells mediated immunity and susceptible to opportunitics infections.
After penetrating the cells and uncoating, a DNA copy is transcribed from RNA genome by thr reverse transcriptase enzymes that is carried by infection viron. Then the DNA is transport to nucleus and integrated randomly within the host. Then integrated virus is known as proviral DNA.
Investigations:
Look for antibodies against HIV
- Serology using ELISA screening test
- Western blot test
- PCR
Clinical features:
General features
- Weight loss
- Heptomegaly
- spleenomegaly
- Chronic diarrhea
- Fever
- Night sweats
Specific features like
Opportunistic infections
- Candidiasis
- Cryptococcal meningitis
- CMV retinitis or colitis
- Various type of TB
Specific oral condtion:
- Candidiasis
- Oral hairy leukoplakia
- Kaposi sarcoma
Gastrointestinal Disease:
- CMV
- Crptosporidum
- Microsporidum
- Mycobacterium avium intracellulare ( MAI )
Fever disease:
- Hepatitis B
- Hepatitis C
- Liver enlargement
Respiratory disease:
- Pnemocystis carinii Pneumonia
- TB
- Bacterial infection
CNS
- Focal brain disease
- Diffuse brain disease
- Meningitis
- Spastic paraparesis
- Incontinence
- Primary CNS lymphoma
- Dementia
- Spinal cord and nerve root or peripheral nerve dissection
- Kaposi sarcoma
- Genital cancer
Precaution:
Sexual:
- Comprehensive sex education program in schools
- Public awarness campaogns for HIV
- Easily accesible / discreet testing centres
- Safe sex pratice ( avoiding penetrative intercourse, delaying sexual debut, condom use, fewer sexual partners)
- Targeting safe sex method to high risk groups
- Control of SIIS
- Effective treatment of HIV infected persons
Parenteral:
- Blood product transmission ( screening of donated blood should be done)
- Not to share syringes and needles
Prenatal:
- Routine opt-out antenatal HIV antibody testing
- Counselling about planning /risk of pregnancy if HIV seropositive
- Measures to reductive vertical transmission
Occupational:
- Education/training
- Post exposure prophylaxis
Management:
Management of HIV involves both treatment of the virus and opportunistic infection
Aims:
- Reduce the viral load
- Improve CD4 count
- Improve quantity and quality of life
- Reduce transmission
Drugs:
Antiretroviral treatment
It is classified into three parts:
1.Nucleoside reverse transcriptase inhibitors (NRTI’s)
- Zidovudine
- Stavudine
- Lamivudine
- Abacavir
- Zilcitabine
- Didanosine
2. Non-nucleotide reverse transcriptas inhibitors (NRTI’s)
- Nevirapine
- Efavirenz
- Delavidine
3. Protease inhibitors (PI)
- Indnavir
- Ritonavir
- Lopinavir
- Ataznavir
- Saquinavir
- Tipranavir
- Amprenavir
4. NRTO’s used for
- Peripheral neuropathy
- Pancreatitis
- Hepatic stenosis
- Anemia
- Myopathy
- Cardiomyopathy
- Extremity fat loss
5. NNTRI’s
- Rash
- Steven-jo-hnson syndrome
- PI’s are used for
- Gastrointestinal intolerance
- Insulin
- Bleeding in Hemophilia