Flashcards in Misc Deck (180)
What is the CD4 count for type C1, C2 and C3 HIV?
1 - >500
2 - 200-499
When does CD4 count cause immunodepression?
Investigations for HIV?
HLA-B 5701 status, lymphocyte subsets
ELISA in 6-8 weeks, western blot, immunofluorescence assay, nuclei acid testing
serologic testing algorithm for recent HIV serovconversions (STARHS) to identify recent activation
viral p24 antigen, isolation of virus in culture, detect IgG antibodies to envelope components
What is screened in a virology screen for HIV?
HIV antibody, HIV viral load, HIV genotype, hepatitis serology, CMV antibody, syphilis screen
Treatment of HIV?
educate, transmission reduction, advice, contact tracing, psychological support
highly active antiretroviral therapy (HAART)
2xNRTI + 1xNNRTI or
2xNRTI + 1xPI or 1xII
(non nucloside reverse transcriptase inhibitor, nucleoside reverse transcriptase inhibitor, protease inhibitor, integrase inhibitor)
What are the co receptor sites in M and T tropic strains of HIV?
M = CCR5
T = CXCR4
Example of a protease inhibitor?
Example of integrase inhibitor?
Complications of HIV?
increased risk of opportunistic infections e.g. toxoplasmosis, CMV. PJP, cryptococcal meningitis, aspergillosis
increased risk of malignancies e.g. Kaposis sarcoma, NHL, cervical, anal
AIDS (5-10yrs post)
Symptoms of AIDS?
candiasis of bronchi, trachea, lungs and oesophagus, lymphoma, pneumocytosis pneumonia, leucocenphalopathy, meningitis, CNS mass lesions, cervical cancer, TB
What is the treatment of HIV based on?
awareness, delivery, clinical services, cost, adherence, efficacy, co morbidities, side effects, 2ndline, combined formulants, paediatric formulants, ease of use
What is the difference between HIV-1 and -2?
they are closely related retroviruses, capable of reverse transcriptase and made up of 9 genes causing genetic variation
What are the 9 genes that code for the HIV genome?
Tat - viral replication and increased host transcription factor production
Rev - binds to RNA to allow export form nucleus and regulate RNA splicing
Nef - increase infectivity
Gag - encodes structural proteins
Pol - encodes enzymes
Env - encodes envelope proteins
Vif - host restriction factor to block replication and mediate degradation
Which three genes help encoding in HIV?
Gag, Pol, Env
What are the different types of tropic medicine?
neoplastic disease, chronic illness, blood dyscrasias, nutritional, envonoming
Examples of vector borne tropical diseases?
dengue, viruses, malaria, protozoa, trypanosomes, leishmaniasis, filaria, trachoma, bacteria, typhus, rickettsia, helminthiases
Examples of soil/water borne tropical diseases?
hookworm, ascaris, buruli ulcer
Examples of faecal oral tropical diseases?
amoebae, giardia, thyphoid, bacteria
Examples of sexual tropical diseases?
HIV and STIs
Examples of airborne tropical diseases?
measles, meningitis, pneumonias, TB
Symptoms of Dengue fever?
fever, headache, severe musculo skeletal pains (back break fever), fever temporarily drops, rash
How is Dengue fever transmitted?
aedes mosquito - in south america and central africa
Examples of arthropod borne viruses?
dengue fever, yellow fever, japanese encephalitis, west nile, o'nyong nyong, chikunggunya
Examples of human to human directly transmissable haemorrhagic viruses?
lassa fever, ebola, marburg, CCHF
have a high case fatality and need a high level barrier nursing of cases advised
What can sand flies (phlebotomus sp) cause, how does it present and what is the treatment?
causes a fever, biopsy shows amastigotes, shows the leishmania species, and treated with sodium stibogluconate
What is African Trypanosomiasis?
the sleep sickness, causing strange behaviour and hard to rouse
transmitted via the tryspansoma bruceii tsetse fly
it is a transient parasitaemia, with lymph gland invasion and chronic meningoencephalitis
Treatment of the African Trypanosomiasis?
IV suramin (urea derivative) and melarsoprol (trivalent arsenic compound), need CSF to diagnose if no symptoms
Symptoms of the Chagas disease?
initial lesion, oedema, transient toxaemia, long latent period, cardiomegaly, CCF, arrhythmia, megooesopghagus, megacolon, destructon of enteric nerve plexus
Tropical infections with short (
arboviral infections (dengue), enteric bacterial infections, paratyphoid, plague, typhus, haemorrhagic fevers