Infectious diseases- Medicine Flashcards
Malaria- uncomplicated falciparum treatment
Artemether with lumefantrine (artemesinin combination therapy)
Or oral quinine plus doxycycline
Malaria- complicated/ severe Falciparum treatment
IV artesunate
IV quinine if artesunate not immediately available- continue till pt can complete full oral course of quinine
Malarial prophylaxis
Malarone = proguanil + atovaquone
Mefloquine (weekly)
Doxycycline
Malaria endemic areas (WHO)
Sub-saharan Africa- majority cases
Others- SE Asia, Eastern Mediterranean, Western Pacific, the Americas
Salmonella- gram pos or neg?
Gneg
Aerobic
Typhoid transmission
Faecal-oral route
Contaminated food and water
Relative bradycardia + fever…
= typhoid fever- pulse rate slow for high fever
Rose spots = ?
On chest and abdomen
Typhoid fever
Mx typhoid fever
IV ceftriaxone 2g OD
or Azithromycin
or PO Ciprofloxacin (once sensitivities identified)
Define PUO
Prolonged fever of > 3 weeks which resists diagnosis after a week in hospital
Typical exam Q patient with Tb
Productive cough
Sputum grows acid fast bacilli
Zeihl Neelson staining: red
Latent TB treatment
3 months isoniazid and rifampicin
or 6 months isoniazid alone
Active TB treatment
Rifampicin and isoniazid for 6 months
Pyrazinamide and ethambutol for first 2 months too
Side effects of Rifampicin
General- nausea, thrombocytopoenia, vomiting
Orange urine/ tears
Drug induced hepatitis
Reduces COCP efficacy/ other drugs that use CYP450 - is a potent liver enzyme inducer
(Red-and-orange-pissin)
Side effects of Isoniazid
Peripheral neuropathy (reduced by giving pyridoxine)
Colour blindness
Gynaecomastia
Drug induced hepatitis
Why is isoniazid given with pyridoxine?
Pyridoxine = B6
to reduce side effect of peripheral neuropathy that isoniazid can cause
(I’m-so-numb-azid)
Side effects of Pyrazinamide
Hyperuricaemia - gout
Arthralgia, myalgia
Drug induced hepatitis
Side effects of ethambutol
Optic neuropathy/ reduced VA/ colour blindness
-Check VA before + during treatment
(EYE-thambutol)
Causes of erythema nodosum
Throat infections- strep primary TB Parasitic infections- amoebiasis Chlamydia HSV Viral hepatitis HIV
Inflammatory causes- IBD, sarcoidosis, lymphoma, leukaemia
What is ghon complex
Ghon focus (small lung lesion due to TB) plus hilar lymph nodes - usually in apical segment of R lower lobe
Where to look when given a TB CXR and you can’t see anything
Check the R middle zone
and upper zones -the most aerated portion of the lungs and tubercle bacilli like them
Pt exposed to HIV, no symptoms- do you test?
Yes at 4 wks
Then at 12 wks if negative result
What CD4 count = end stage HIV/ AIDs
Under 200
Risk of opportunistic infections eg PCP or cyatomegalovirus infection
HIV prophylaxis against PCP?
For CD4<200
Co-trimoxazole (septrin)
HIV Vaccinations
Yearly influenza Pneumococcal once or twice a decade Hep A and B Tetanus Diphtheria Polio Avoid live vaccines
Who is offered ART
Anti-retroviral therapy
everyone with HIV regardless of viral load or CD4 count
When do people develop HIV antibodies by
4-6 weeks normally
definitely by 3 mnths
Screening HIV in pregnancy…
NICE recommends screening all pregnant women
Can HIV women breastfeed
No
What is meningococcous
Neisseria meningitidis
Gneg
diplococci
Most common cause of meningitis
Adults- Meningococcus
Pneumococcus (strep pneumoniae)
Neonates to 3mnths- GBS (group B strep)
HI in up to 6yrs is also a possibility
Suspected meningitis + non-blanching rash, seen in GP, what to do?
Urgent IM benzylpenicillin (Or IV) prior to transfer to hospital
Suspecting meningococcal meningitis
Why do we give dexamethasone in bacterial meningitis
To reduce the deafness and neurological damage
Typical abx treatment for bacterial meningitis
Under 3mnths- cefotaxime + amoxicillin
Over 3mnths- ceftriaxone
(cephalosporins) IV
Vancomycin can be added if risk of resistant pneumococcal infection
When is amoxicillin added to cephalosporin treatment for bacterial meningitis
Cover for Listeria- for >55 years, or immunocompromised, or <3mnths
If a patient with TB develops a headache and neck stiffness what might you be concerned about and how would you investigate this further?
Meningitis
Lumbar puncture= high protein, low glucose, lymphocytosis
MRI scan- leptomeningeal enhancement