Retrovirus Flashcards
Retrovirus family includes
Oncoviridae - HTLV 1,2
Lentiviridae - HIV 1,2
Which HIV is more common in India
HIV 1»_space; HIV 2
Features of HIV Virus
Unsegmented ssRNA
2 copies of RNA
100-120 nm
Reverse transcriptase activity
HIV 1 Serotypes
M - M/C
N
O
P
Subtypes of M serotype of HIV 1
10 subtypes - A to K
Which serotype of HIV 1 is most common in Worldwide and India
Worldwide - HIV 1 Group M subtype B
India - HIV 1 Group M subtype C
Circulating recombinant forms of HIV
CRF-AE : Combination of A and E Serotypes
HIV proteins are classified into
Structural
Non structural
Structural proteins of HIV includes
Env (Envelope)
Gag
Pol
Env (Envelope proteins) of Hiv
Envelope - gp160
Surface - gp120
Transmembrane - gp41
Gag proteins of HIV
Matrix - p17
Capsid - p24
Nucleocapsid - p7
Budding protein - p6
Pol proteins of HIV
RIP
Reverse transcriptase - p66
Integrase
Protease
Non structural proteins of HIV
Tat (Transcriptional transactivator)
NeF (Negative factor gene)
ReV (Regulation of virus)
ViF (Viral infectivity factor)
Vpu/Vpx - unload/release of virus
Vpr - transport from cytoplasm to nucleus
LTR (Long terminal repeats)
Which non structural protein of HIV is responsible for Unloading/release of virion
Vpu/Vpx
Which non structural protein of HIV helps in transport of HIV from cytoplasm to nucleus
Vpr
Attachment of HIV Virus is mediated by
Envelope proteins (gp129, gp41) - attaches to Macrophages or CD4 Cells and Coreceptor binding to Chemomine receptors
R4 strains - Binds to CXCR4 on CD4 cells
R5 strains - Binds to CCR5 on macrophages
Pathogenesis of HIV
Attachment - Endocytosis - Uncoating - conversion of viral RNA to DNA with the help of Reverse transcriptase - viral DNA transported to nucleus (Vpr) - Integration of viral DNA with host DNA mediated by Integrase enzyme - Transcription (RNA formation) - Protein synthesis - new viral particles formed - Release (by Protease enzymes)
Transmission of HIV
Sexual (0.1-1%) - Homosexual routes, Heterosexual routes, unprotected receptor anal course, vaginal intercourse
Blood transfusion (>90%)
Needle stick injury - 1:300
Needle sharing - 1:150
Vertical (30%)
Clinical forms of HIV
Acute HIV syndrome
Clinical latency
PGL (Persistent generalized Lymphadenopathy)
ARC (AIDS related complex)
Clinical features seen in Acute HIV Syndrome
Fever/weight loss
Headache
Pharyngitis
Lymphadenopathy
Skin rash
Myalgia
Nausea/vomiting
Hepatosplenomegaly
Clinical latency form of HIV
Asymptomatic
CD4 Count goes down
HIV RNA levels increases
Persistent generalized Lymphadenopathy form of HIV
Enlarged LN - two or more than 2 non contagious extrainguinal sites LN
AIDS related complex
When CD4 <200/mm3 - definition of AIDS
Opportunistic infections
Opportunistic infections when CD4 count is less than 500
Tb
Bacterial pneumonia
Oropharyngeal Candidiasis
Non typhoid Salmonellosis
Kaposi sarcoma
Non Hodgkin’s lymphoma
Herpes zoster
Opportunistic infections seen in Hiv when CD4 <200
Pneumocystis jiroveci pneumonia
Oesophageal Candidiasis
Herpes simplex ulcer
Isospora belli diarrhea
HIV Associated dementia
Opportunistic infections seen in HIV when CD4 <100
Cerebral Toxoplasmosis
Cryptococcal Meningitis
Cryptosporidiosis
CMV
MAC
PMLE
Opportunistic infections seen in HIV when CD4 <50
CMV
MAC
Toxoplasma gonii retinitis
CDC AIDS Definition
CCCCCCPPHKM
Candida - trachea, esophagus
Cryptococcus - meningitis
Cryptosporidium - chronic diarrhea (>1 month)
CMV colitis - Seringous ulcers
Cerebral toxoplasmosis - Seizures
CNS Lymphoma
PMLE
Pneumocystis CD<200
HSV
Kaposi sarcoma (HHV8)
MAC - CD<50
WHO Definition of AIDS
Atleast 2 major signs in combination with at least 1 minor signs
Major Signs - Weight loss (>10% of body weight), Chronic diarrhea, Prolonged fever
Minor signs -
Persistent cough for > 1 month, generalized pruritic dermatitis
H/O of herpes zoster
Oropharyngeal Candidiasis
Generalized Lymphadenopathy
Most common opportunistic infection in HIV Pt
Tb
Most common opportunistic fungal infection in HIV pt
Candida
Most common space occupying tumor in HIV pt
CNS Lymphoma
Most Common glomerulonephritis in HIV Patients
FSGS (HIVAN)
Most common Non Hodgkin’s lymphoma in HIV pt
DLBCL
Most common Hepatitis in HIV pt
Hepatitis B
Most common skin symptom in HIV
Seborrheic dermatitis
Most common endocrine symptom in HIV pt
Lipodystrophy
Which one to treat first im case of Tb with HIV
First give ATT then after few weeks start ART (To prevent immune reconstitution inflammatory syndrome)
Lung infections and X rays findings seen in case of HIV
Pneumococcus - Lobe consolidation
TB - Snow storm/Hazzy pattern
Pneumocystis jiroveci - Perihilar opacities (CD4 <200)
Diagnosis methods for HIV
CD4 Count
ELISA - Sensitive (4th generation enzyme immunoassay)
Western blot - specific
Immunofluorescence assay
Lind or dot immunoassays
RT PCR (Even 40 copies detected)
Pediatric HIV - DNA PCR
ELISA (4th generation enzyme immunoassay) in HIV
Detection of p24 antigen + antibodies
If +ve - Do HIV 1/HIV 2 antibody differentiation immunoassay - If negative - HIV 1 NAT (Definitive)
Western blot findings according to WHO
Antibody against 2 envelope bands (gp120,gp41) with or without gag/pol bands
1st to rise in HIV, HIV RNA or p24
HIV RNA > p24
HTLV- 1 Causes
Human T cell leukemia lymphoma virus
Causes adult T cell leukemia lymphoma, Tropical spastic paresis
Microscopic examination finding in case of Adult T cell leukemia Lymphoma
Clover leaf cells
Mode of transmission of HTLV -1
Blood
Body fluids (breast milk)
