Introduction
First case of pediatric AIDS was diagnosed in 1982, in India first seropositive infant was diagnosed in 1987. In India, 85,000 HIV infected persons and 7012 AIDS cases were reported by NACO in March 1999. Maharashtra accounted for approximately 50% of all reported cases. The end of 1999 reported all over world 11.2 million AIDS orphans. AIDS orphan is the term used for the child who has lost his/her mother to HIV/AIDS before the age of 15.
Transmission: - 1. Vertical - In absence of maternal anti-retroviral treatment, the risk for HIV infection among infants range from 10 -45%. Risk factors for perinatal transmission of HIV - Clinical: Premature delivery 4 hours chorioamnionitis, non-receipt of caesarean section before onset of labour. 2. Blood - HIV transmission rate from receipt of infected blood products is approximately 100%. Serology could be negative in cases with window period, in such cases screening by p24 antigen or HIV RNA assays might be warranted. 3.Body fluids - HIV replicates only within cells that it infects, especially those that express the CD4 antigen, such as some helper T lymphocytes, monocytes and macrophages. It is likely that because blood and semen have larger quantity of CD4 antigen expressing cells, they are the body fluids most often associated with transmission of HIV infection. HIV is recovered from other body fluids but exposure to these fluids has not been documented to result in HIV infection unless these fluids are contaminated with blood. 4. i/v drugs, 5. Sexual Abuse, 6. Breast Feeding Pediatric
HIV Classification - Category N - Not Symptomatic, Category A - Mildly symptomatic (i.e. children with two or more of the following: lymphadenopathy, hepatomegaly, splenomegaly, dermatitis, parotitis, recurrent/persistent URI), Category B - Moderately symptomatic (i.e. anemia, neutropenia, pneumonia, oropharyngeal candidiasis, cardiomyopathy, lymphoid interstitial pneumonia, etc). Category C - Severely symptomatic (i.e. children with any of the conditions listed in the surveillance case definition of AIDS).
Clinical Manifestations - 1. Rapid Progressors -approximately 20% of patients, these children progress very rapidly to AIDS defining conditions, rapid loss of CD4 cells within the first two years of life. 2. Intermediate Progressors: 60 -75% of children develop severe immunosuppression by 7 -8 years of age, with a much more gradual loss in CD4 cells. 3. Long term Survivors - 5 -10%, minimal to no symptoms of HIV disease and a normal to minimally decreased CD4 cells count by 8 years of age.
Diagnosis of HIV infection in Children - The diagnosis of HIV infection among children begins with the identification of HIV infection in women before and during each pregnancy by voluntary screening during pre natal care. The rapid and early diagnosis of HIV infection in exposed infants is difficult because of transplacental passage of maternal IgG antibodies to the virus that are present in infants up to 18 months of age. The diagnosis of HIV infection among young infants now relies exclusively on virologic assays. Virologic assays are also helpful to confirm infection in patients with advanced stage of disease who have inadequate specific antibody production. Infants born to HIV positive mothers - Infants who initially have negative virologic tests should be re-evaluated at 1 -2months and 4 -6 months. Laboratory diagnosis Detection of specific antibodies: Screening tests - ELISA/Rapid test/Simple test. Supplemental tests - Western blot/IFA/RIPA. Detection of specific antigens: p24 antigen detection, reverse transcriptase. Detection of viral nucleic acid: In situ hybridization, PCR a. genotyping of HIV, b. viral load assay. Isolation or culture of virus.
HIV Testing Strategies - Strategy I - All samples are tested with one ELISA or rapid /simple. Strategy II - All samples are first tested with one test. Any reactive samples are subjected to second test based on a different principle and/or different antigenic preparations. Strategy III - All samples are first tested with one test. Any reactive samples are tested with a different test. Samples found reactive by the second test are subjected to a third and different test.
Opportunistic Infections: - Pneumocystis Carinii Pneumonia, S. pneumoniae, Salmonella, Staph, H. influenzae, Pseudomonas.
Management - 1) HAART: Highly Active Anti-Retroviral Therapy, 2) Prophylaxis against opportunistic infections. 3) Supportive and symptomatic treatment.
Principles of antiretroviral therapy: 1) Monotherapy is contraindicated because it results in suppression of HIV replication thereby allowing the emergence of drug resistance. 2) All children with HIV infection should be offered specific ART irrespective of their clinical status, CD4 counts or HIV RNA copy number. 3) All drugs approved for adults can be used for children. 4) Early initiation of therapy is advantageous because it slows deterioration of immune function, delays progression of disease, reduces incidence of opportunistic infections and prolongs patient survival. 5) Treatment has to continue even after the CD4 T lymphocyte counts have reached normal level.
Prevention: 1) Perinatal transmission- prevented by giving zidovudine (100mg five times a day during T2, T3) i/v bolus of 2mg/kg at start of labour, 1mg/kg/hour thereafter caesarean section, zdv (2mg/kg/dose 6 hourly) to baby for 6 weeks and avoidance of breast feeding. 2) Safe transfusion of blood. 3) Post-exposure prophylaxis. Click here for References |
