Sexual Transmitted Disease: Epidemiology And Treatment Of HIV Flashcards
AIDS
Opportunistic infections
Kaposi’s sarcoma
Some lymphomas
39.5 million people have AIDS
HIV
Virus isolated in AIDS 9.6 kilo bases Present in genitive secretions Variable transmission Needles Vertical transmission-> breast feeding, pre and peri partial colescreon
Opportunistic infections and CD4
Remains stable in first viral peak but decreases with second
As the CD4 count decreases the more opportunistic pathogens infect the body
250-> progressive generalised lymphadenopathy
200-> skin infections, PCP, diarrhoea
150-> tumours
100-> mycobacterium avium complex, cryptococcal meningitis, toxoplasma encephalitis
50-> oesophageal candidia, HSV, HZV, molluscum, CMV
Clinical presentation of AIDS
Lymphadenopathy Oral candida Dysphagia Weight loss Dry skin Shingles Current HSV Emergencies: Respiratory CNS Diarrhoea PUO Blurred vision
HIV and the lung
Infections -> fungi-> pneumocystis jivoveci, cryptococcus aspergillus -> mycobacteria-> m. Tuberculosis -> bacteria-> strep pneumoniae Neoplasms -> kaposi sarcoma -> lymphoma -> CA of lung
Pneumocystis jiroveci pneumonia
Repeated inhalation in from childhood Replication increased in immunocomprimised -> binds fibrocontectin-> injures type 1 alveolar cells-> increased permeability-> pneumontitis Subacute onset Systemically unwell Dry cough and short of breath Variable signs, O2 desaturation Bats wing interstitial CXR shadowing
treatment of PJP
Steroids for low O2 sats 14-21 days: Co- trimoxazole IV or oral Trimethoprim Pentamidine Clindamyciatovaquone Prophylaxis-> co-trimoxazole, dapsone
Investigations of PJP
Sputum-> microscopy/immunofluorescense, PCR, induced
Bronchoscopy-> BAL, biopsy
HIV and the CNS
Headache
-> with neck stiffness-> meningitis-> cryptococcus, TB, syphillis, aseptic toxoplasmosis, lymphoma, PML, abscesses,
-> with focal signs-> cryptococcoma
Focal signs no headache-> CVA
Change in conciousness-> CMV encephalitis, toxoplasmosis, lymphoma
Change in cognition-> AIDS dementia, depression, PML
Myelopathy-> vacuole myelopathy, CMV, VZV
Neuropathy-> HIV, VZV, CMV, drugs
Myopathy-> drugs
TB meningitis
Subacute onset
CSF-> increased lymphocytes and protein, decreased glucose
In the immunocomprimised may be associated with disseminated disease
-> Miliary-> many small lesions
-> multiple sites but not Miliary
Quadruple therapy-> Rifampicin, isoniazid, pyrazinamide, ethambutol
Cryptococcal meningitis
Cryptococcus neoformans-> inhaled environmental fungus
Pneumontitis filled by dissemination
Can seed to skin, prostate and CNS
May present like any other meningitis
If CD4 and inflammatory response is poor-> atypical
Amphaticin B for two weeks and fluconazole for life
Focal CNS lesions
Non infectious-> tumour, primary CNS lymphoma, infarct
Infectious-> bacterial brain abscess, tuberculous, toxoplasmosis
Immunocomprimised also-> nocardia, fungi (aspergillosis, cryptococcus, endemic mycoses), toxoplasmosis
Immunocompetent-> bacterial brain access
Immunocomprimised-> toxoplasmosis
Toxoplasma encephalitis
Toxoplasma Gondi acquired from cats or food
Cysts lie dormant and reactivate when immunocomprimised
Subacute onset
Clinical features due to a SOL or diffuse parenchymal disease plus fever
Serology and CT/MRI
SOL-> lymphoma, cryptococcoma, tuberculoma
Pyrimethamine and folinic acid, sulphadiaxine, continue as life long prophylaxis
Mycobacterium avium complex infection
Environmental, atypical mycobacteria present in soil and water Inhaled or swallowed Hepatosplenomegaly Lymphadenopathy Bone marrow involvement Take blood culture and bone marrow Clarithromycin and ethambutol
Cancers associated with HIV
Kaposi sarcoma
Non Hodgkins and Hodgkin’s lymphoma
Antogenital neoplasia
Co incidence with lung
Types of anti retroviral drugs
Nucleoside analogues-> NRTI’s eg zidovudine
Non nucleoside analogues-> nevirapine, efavirenz
Protease inhibitors-> PI’s eg saquinavir
Fusion inhibitor-> enfuvirtide
Principles of anti viral therapy
AZT monotherapy-> reduces HIV viral load-> resistance develops
AZT+3TC (two NRTI’s)-> reduces vial load more-> resistance develops-> increase lire expectancy by 6 months
PI or NNRTI-> reduce vial load by the same as two NRTIs
Minimum of 3 drugs are required for prolonged benefit and resistance mat not develop for 2-5 years
Sequential combinations prolongs life expectancy by > 10 years
Issues with anti retro virals
Toxic items
Drug interactions
Eligibility issues
>£6000 per year however cheaper than hospital care for infections
Anti retroviral regimes
1) 2NRTI+1NNRTI
2) obtain genotype resistance testing, ritonavir boosted PI+2NRTI
Side effects of anti retrovirals
Gastrointestinal upset
Rash
Disturbance of LFTs
Mitochondrial toxicity
NRTI-> anaemia, myopathy, peripheral neuropathy, hypersensitivity
NNRTI-> psychological disturbance, nervirapinhepatotoxicity
PI-> dyslipidaemia, lipodystrophy
