Infectious Diseases And GUM Flashcards
Gonnorhea
N.Gonnorhea - Encapsulated and therefore resitant to phagocyosis
Large ASx resevoir - Pharynx/rectal/cervical
Disseminated dx - in females = penicillin sensitive
Opthalmoplegia neonartu - Systemix Abx and Eye drops
> 10% = resistant to Penicillin + quinolones
–> Tx = CEPHLASPORIN - IM CEFTRAXONE + PO azithromycin
Syphillis
Treponem Pallidum
Transmission: SExual > Blood borne.
Diagnosis:
1) Serology = 2 x specific Ag test (EIA or TPHA) + Quantitive PCR
2) Dark ground microscopy - of tissue from Chancre or rash
3) Treponem PCR - Early syphillis Ulcer
In secondary syphillis - haem spread:
- Mucocutaneous - non-itchy rash
- LN
- Neuro - CN palsy/ Meningitis
- Occular - ant. uveitis
- GI - Hepatitis or proctitis
- Rheu - polyarthritis
Tx = Benzylpenicillin or Tetracycline
REINFECTION ??? –> use rapid plasma reagin - all others stay +ve despite txx
Chlamydia
Most common bacterial UTI –> Non-gonnocal urethritis.
Complications:
- Female - PID.
- Male - prostatitis/epididymitis
- Babies - Neonatal conjunctivitis or pneumonitis - Systemic Erythromycin
In UK serovaa D + K most common
Other Complications:
- Trachoma - corneal scarring = Serova A/B/C
- Lymphogranuloma venerum = rectal inflamm + prostatitis - in MSM - Serova L1/L2/L3
Inx - NAATs
Mx in Adults = TETRACYCLINE OR AZITHROMYCINE
Risk factors for Aids
Most common transmission is M+F > MSM > Blood > IVDU
HIV 1 - most common worldwide
HIV2 - Most common in West Africa
RF:
- Seroconversion or adv disease
- concurrent STI
- Concurrent Hep C
- High Viral Load
Maternal –> Fetal RF = BREASTFEEDING reduce transmission by:
- Antiretroviral before 3rd trimester
- Avoid Breastfeeding
- If detect VL @ 36 weeks –> C-section
HIV Mechanism
HIV follows CD4 cells: T-helper, B cells, Macrophages and CNS cells
HIV –> Decreased CD4 and therefore a low CD4:CD8
Markers assoc w/ Progression:
- Low CD4
- High Viral Load
Seroconversion:
- up to 3/12
- General unwekk sx, can ave meningo-encephalitis or arthropathy
- Can’t detect HIV antibody during this time
- Can detect HIV p24 Ag or HIV-1 (at 1 month)
Stages of HIV infection
Stage 1: Seroconversion
Stage 2: ASx
Stage 3: Persistent Generalised LN
Stage 4a: AIDS related complex –> Not AIDS defining disease
Stage 4b: AIDS defining illnesses
HIV - PCP
Q Stem: Persistent cough, with low sats or desat on exercise and HIV (CD4<200)
CXR: Bilat perihilar LN
Inx - Brochoalveolar lavage (BAL) –> Silver stain or immunoflourescence
Mx:
- IV Co-Trimaoxazole or IV pentamidine (Sev dx)
- Steroids - improve prognosis
Prophylaxis - Co-trimox and nebulised pentamidine:
- Prev PCP or CD4 <200 (until >200)
HIV - Pulm TB
Q Stem - may be similar to PCP –> AFRICAN PT or EXPOSURE –> Extrapulm TB or Mycobacterium Avium intracellulare
Atypical features:
- Atypical CXR
- Extrapulmonary Spread
- Atypical organism - Mycobacterium avium intracellulare
HIV - GI disease
Common:
- Oesophageal candida
- oral hairy lukoplakia
- KArposi sarcoma
- gingivitis
- lymphoma
- CMV
- HSV
Diarrhoea:
Cryptosporidium –> porfuse watery diarrhoea
Salmonella –> Atypical severity –> bacteraemia.
Inx - Stool culture or ZN Stain (Cryptosporidium) Or Biopsy
HIV - Neuro diseases
Cerebral Toxoplasmosis:
- Px - Focal Neuro
- Inx: CT - ring enhancing lesions + Toxoplasmosis IgG serology
- Tx: Pyrimethamine + Sulfadiazine
CNS Lymphoma:
- EBV
- Assoc. with EBV
- CT
- Tx = Steroid + Chem
NOTE: distnguish between toxoplasmosis and lymohoma with Thalium SPECT (neg in toxo and pos in lymphoma)
Cryptococcal meningitis:
- Px: Mengitis
- Inx - Cryptocoocal Ag in Blood or CSF
- Tx - Amphotericin or Fluctosine –> Liver/renal fx
Neurosyphillis:
- Myopathy, retinitis, meningitis
- Inx - Syphillis serology
- Tx - IM Procaine penicillin + PO Probenacid
CMV Retinitis:
- CD4< 50
- Px : Blurred or LOV
- Signs: Soft Exudate + Retinal haemorrhage
- Tx: Ganciclovir.
HIV/ AIDS Tx
HAART = 2x NNRTI + (NRTI or PI)
IL-2 can be used to icrease CD4 # if good supression of HIV but poor CD4 count
If Fx respond to Tx –> Salvage therapy = Add Enfuvirtide
Monitoring:
- Clinical assess
- CD4
- Viral Load
- Renal/Hepatic fn
- Cholesterol/BGL
- Lactate
If Viral Load high on 2x ocassions –> Test for Viral Resistance
These patients req >90% Adherence
PEP and PrEP
4 weeks of Truvada / Kahetra
Take within 72 hours –> decrease transmission by 70-80%
PrEP - if high risk but not infected - req LT adherance (As long as exposure)
Live vaccines
Give 4 weeks apart
Human bite organisms and management
Staph A
Strep
Eikonella corrodons
CO-AMOXICLAV
Hep B vaccination response
Measure anti-HBs
> 100 —> no further bad
10-100 —> one additional vax dose
<10 —-> test for current or post infection and and repeat course of 3 vaccines
Urine dip tests
+ nitrates and + luecocytes
Then gram negative - E. coli
If symptomatic and only leukocytes consider a Gram + infection
G+ can’t concert nitrates to nitrites and therefore will be negative on urine dip
Bacterial vaginosis
Fishy discharge
Amsel criteria:
- thin white homogenous discharge
- clue cells on microscopy
- vaginal pH >4.5
- positive whiff test
Management
PO metronidazole
Renal transplant and infection
Think CMV
If imunnosupressed and approx 4/12 after commencement of immunosuppressant then think CMV
Genital warts
HPV 6 + 11 —> predispose to cervical Ca
Single + keratinised- cryotherapy
Multiple and non-keratinised - topical podophyllum
2nd line - topical imiquimod
Rubella in preg
Adult - headache/fever/URTI
1st trimester:
- congenital rubella syndrome
- deafness
- cataract
- pda
- developmental delay
Toxoplasmosis
Parasite from cat faeces
Features:
- primary —> infectious mononucleosis like sx
- reactivation —> CNS multiple ring enhanced lesions
Pregnancy:
- Early - frontal retinochoroiditis, encephalo-myelitis, hydrocephalus or microceph
- late: develop above but as an infant - NORMAL BIRTH
Inx = serology
IgG - previous
IgM - acute
Mx:
Non specific tx
If reactivation —> Pyrimethamine, sulfadiazine + Folinic acid
Pregnancy - Spiramycin
Toxoplasmosis vs CNS Lymphoma
- both increased Immuno deficiency:
Toxo - multiple lesions. Lymphoma- single
Thallium spect: toxo neg. lymphoma +
CMV
Ft:
Intraceebral calc
Helatosplenomegaky
Retinitis - in HIV - CD4 <50 —> IV ganciclovir
Varicella
Primary infection. - chickenpox —> latent in. Sensory ganglia
Reactivation —> dermatomal shingles
Pregnancy:
- if contact and unsure if immune:
VZIG
- untreated —> congenital varicella syndrome = limb hypoplasia + scarring of dermatomes
If adult gets exposed and unsure if exposed —> test IgG —> negative —> VZIg
Parvovirus in preg
Foetal anaemi
Hydrous fetalis - accumulation in fluid in >=2 feral compartments has
Foetal death
Gram +ve mnemonic
|Str|ange |Staph|y’s |act| |list| |enter|ed |my| |new| |Cl| |C|arrier |ba|g
Strep Staph Actinomyosis Listeria Enterrococcus Mycobacteria Pneumococcus Clostridia Corynbacterium - diptheria Bacillus
G+ve Bacilli
CLara DATTA
Clostridia Listeria Diptheria Anthrax TB Tetanus Actinomyces
Strep Pnemo + Viridans
Alpha Knight tournament
Strep Pyogenes
Pyogenie bakery
Strep Agalactiae
Galactic Baby
Staph A
Golden Staph of Aureus
HSV
HSV-1 –> life long carriers
HSV-2 –> used to be known for genitals but now crossover
Can get mengitis or temporal lobe encephalitis.
Diagnosis of enceph: Viral PCR on CSF + MRI
Mx: IV Aciclovire
VZV
primary infection –> Chickenpox –> latent in sensory ganglia
Reactivation –> Shingles
Complications –> Pneumonitis or cerebral ataxia –> IV antiviral
If pregnant exposure and NOT immine –> VZIG
CMV
Primary –> ASx or Gladnular fever-like or GBS or BElls
> 80% of >60 yr olds have it, but becomes an issue if immunosupressed.
AIDS + CMV –> CMV retinitis, oesophagitis or colitis
Tx - ganciclovir
EBV
Ingectious mononucleosis Burkitts Lymphoma Lymphoma in HIV Nasopharygeal Ca Oral Hairy Leukoplakia
HHV8
KArposis sarcoma
Primary effusion lymphoma
Castlemans disease - lymphoproliferative disorder with enlarged LN
ABx Mechanism of action - non-protein synth inhibitors.
NITtu MET |SUL|tan in CEPtember with a |FLU|id PEN and a CAR
DNA synth inhib:
Nitrofurans
Metronidazole
Tetrahydrofolate inhib:
Sulphonamides - Trimethoprim
Peptidoglycan inhib:
- Cephlasporin
Penicillin
Carbapenems
DNA Gyrus inhib:
Fluroquinolones