Infectious diseases and STIs Flashcards
gram positive cocci & how to differentiate them
staph (clusters)
strep (chains)
enterococcus
coagulase positive = staph aureus
coag neg = s.epidermis
a-hameolytic = strep viridans (sanguinis, mutans)
b-haemolytic = strep pyogenes, s.agalactiae & enterococci incl s.bovis
gram -ve cocci
diplococci: Neisseria meningitidis + Neisseria gonorrhoeae,
Moraxella catarrhalis
gram positive rods
ABCD L
* Actinomyces
* Bacillus anthracis, bacillus cereus
* Clostridium [anaerobic: c.diff, perfringens, tetanus]
* Diphtheria: Corynebacterium diphtheriae
* Listeria monocytogenes [SBP, meningitis]
& nocardia
gram negative rods
Remaining organisms are Gram-negative rods, e.g.:
- Escherichia coli
- Haemophilus influenzae
- Pseudomonas aeruginosa
- Salmonella sp.
- Shigella sp.
- Campylobacter jejuni
aerobic: enterobacter, proteus, salmonella, shigella, yersinia
anaerobic = bacteroides
chlamydia tx
pregnant and non-pregnant
Doxycycline for 7 days
If CI/not tolerated: azithromycin (1g one dose, 500mg OD 2ds)
Pregnancy: can use azithromycin, erythromycin or amoxicillin
Suggest azithromycin 1g stat
toxoplasmosis tx
pyrimethamine + sulphadizine
crypto meningitis tx
amphotericin B + flucytosine
schistosomiasis tx
praziquantel
strawberry cervix, wet mount: motile trophozoites, frothy yellow/green PV discharge
- what is it?
- tx?
Trichomonas: strawberry cervix, wet mount: motile trophozoites, frothy yellow/green PV discharge
• Mx: oral metro for 5-7ds or one 2g dose
Microscopy: clue cells
BV
thin white PV discharge
genital warts tx
Genital warts
• 1 keratinised wart: cryotherapy
Multiple non-keratinised: topical podophyllum
red cysts on Z-N stain
Cryptosporidiosis
• Modified z-n stain of stool: red cysts
• If immunosuppressed may need: nitazoxanide
fever in returning traveller 1st week
- with purpura?
- jaundice?
- safari + purpura?
dengue: purpura
lepto: water and jaundice
tick typhus: safari and purpura
fever in returning traveller 4 weeks - bloody diarrhoea? - normal wcc, splenomegaly? - any pres
bd: amoebiasis
normal wcc: enteric fever
any: falciparum
amoebiasis tx
Invasive amoebiasis: tx with metro or tinidazole, then tx again with diloxanide furoate (because need to then get rid of dormant phase which is res to met or tini)
Rash, headache + 1 or more eschars & history of foreign travel - dx? tx?
Rickettsiae:
• Rash, headache + 1 or more eschars & history of foreign travel
○ Weil-felix reaction +ve
○ Tx: tetracyclines (doxycycline etc)
• Except Q fever: pneumonia with no rash (coxiella burnetti)
-ve weil-felix reaction
what does strep pyogenes cause? (5)
Rheumatic fever Scarlet fever Most common cause of sore throat in UK Post strep GN erysipelas
diarrhoea 3ds after eating - most common cause?
Shigella sonnei = most common cause of gastroenteritis
- 3ds after visiting a restaurant get diarrhoea, on 3rd day of illness becomes bloody - Similar pic to campylobacter
jaundice suffused conjunctivae muscle aches - dx?
leptospirosis
sickle cell - 2 organisms cause problems
- Parvovirus > aplastic anaemia
Salmonella > bone and joint infections
how does cholera cause diarrhoea
2nd messenger activation of G proteins»_space; cAMP release
cellulitis abx choice incl pen allergic
- Mild/mod: flucloxacillin
- Pen-allergic: Clarithromycin, erythromycin (in pregnancy) or doxcycline
Severe: co-amoxiclav, cefuroxime, clindamycin or ceftriaxone.
orf fts
In humans - on hands and arms
1. small, raised, red-blue papules 2. Then: increase in size to 2-3 cm& become flat-topped and haemorrhagic
Cause: parapox virus.
what test to dx HIV seroconversion (2 options)
Seroconversion: HIV PCR or p24 antigen test (Abs may not be present yet)
leprosy
- 2 types
- mx
· Mx: rifampicin, dapsone, clofazimine
Low degree of cell mediated immunity → lepromatous leprosy (‘multibacillary’)
• extensive skin involvement
• symmetrical nerve involvement
High degree of cell mediated immunity → tuberculoid leprosy (‘paucibacillary’)
- limited skin disease - asymmetric nerve involvement → hypesthesia - hair loss
DETAILS
· granulomatous disease
· primarily affecting the peripheral nerves and skin
· Cause: Mycobacterium leprae.
Features
• patches of hypopigmented skin - buttocks, face, and extensor surfaces of limbs
• sensory loss
The degree of cell mediated immunity determines the type of leprosy a patient will develop.
abx for human bite? animal bite (incl pen allergic)
Animal bite: co-amox
- Pen-allergic: doxy + metro
Human bite: co-amox
anthrax
- fts
- mx
Black painless eschar
Tx with cipro
NOTES
Cause: bacillus anthracis (aerobic)
Fts:
- 2-5ds after inoculation: itchy vesicle - Rapidly progresses >> painless black eschar (cutaneous malignant pustule but no pus) - Usually not tender - Can be oedema ++ around the lesion (can > compartment syn or nec fasc) - Regional lymphadenopathy - Can cause GI bleeding
typhoid cause fts comps mx
Cause: salmonella (aerobic gram neg rods)
Features
• initially systemic upset(headache/fever/arthralgia)
• relative bradycardia
• abdominal pain, distension
• Constipation
• rose spots: on the trunk in 40%, more common in paratyphoid
Comps
- osteomyelitis (esp sickle cell disease) - GI bleed/perforation - meningitis - cholecystitis - chronic carriage (1%, more likely if adult females)
DETAILS
- Salmonella group contains many members: most cause diarrhoeal diseases
○ aerobic, Gram-negative rods
○ not normally present as commensals in the gut.
Typhoid: salmonella typhi
Parathyroid: salmonella paratyphi (types A, B & C)
- enteric fevers: systemic symptoms such as headache, fever, arthralgia.
Pathophysiology
• typhoid is transmitted via faecal-oral route (also contaminated food and water)
Tx: cipro
- But if been to asia, probs resistant: azithromycin - Severe: IV cef - 14ds
3rd week of illness bowel perf
Dx: large volume blood culture
botulism
- cause
- what effect does the toxin have
- fts
- mx
Inhibits release of Ach at synapses
Diff to GBS as botulism descends
As soon as clinical suspicion: give botulism antitoxin & supportive care
NOTES
Tx: botulism antitoxin and supportive care
• Antitoxin only effective if given early: once toxin has bound, its actions cant be reversed
Ft • Fully conscious, no sensory disturbance • Flaccid paralysis • Double vision • Ataxia • Bulbar palsy
Clostridium botulinum
• Gram +ve anaerobic bacillus
• Produces botulinum toxin: irreversibly blocks release of Ach
• Cause: contam food, IVDU
meningitis if in community? what abx for what type if allergic to penicillin? also give?
contacts of what get what
Do an LP if no signs of raised ICP
In community and suspect meningococcal: IM benpen (if doesn’t delay transfer to hospital)
Initial abx
· <3mos: IV cefotaxime + amoxicillin (or ampicillin)
· 3mos-50y old: IV cefotaxmine (or ceftriaxone)
· >50y old: IV cefotaxime/ceftriaxone + amoxicllin/ampicillin
Know the type
· Meningococcal: IV benpen or cefotaxime/ceftriaxone
· Pneumococcal/haemophilus influenzae: IV cefotaxime/ceftriaxone
· Listeria: IV amoxicillin/ampicillin + gentamicin
Hx of immediate hypersens to penicillin/cephalosporins: use chloramphenicol.
Also: IV dex (reduce risk of neuro comps
- But don’t give if: septic shock, meningococcal septicaemia, immunocomp, meningitis after surgery
Contacts of meningococcal meningitis
- Oral cipro (1 dose)
meningitis
cysticerosis - cause, mx
hydatid disease - cause, mx
Cysticercosis
• Cause: Taenia solium (from pork) and Taenia saginata (from beef)
• management: niclosamide
Hydatid disease
- Cause: dog tapeworm Echinococcus granulosus management: albendazole
melioidosis
- cause
- tx
- RF
- syms
Cause: gram-negative bacterium Burkholderia pseudomallei
Treatment:
• Initial intensive therapy: IV ceftazidime, imipenem, or meropenem for 10–14 days
• Then eradication therapy: oral TMP/SMX (plus doxycycline) for 3–6 months
• Adjunct therapy: abscess drainage.
Risk factors:
• DM (the strongest risk factor)
• Chronic renal, liver, or lung disease (e.g., cystic fibrosis)
• Immunocompromised states (e.g., malignancy, long-term glucocorticoid use)
• Occupational exposure: agricultural work
Sign and symptoms:
• Incubation period: 1-21 days ( mean around 9 days)
• Sym cases can be acute, chronic (> 2 months), or reactivations of latent infection.
• Clinical features depend on the infected organ:
Acute pulmonary infection (most common): wide range of presentations (mild to severe)
• - Localized infection: skin ulcer, nodule, or abscess.
• - Visceral abscesses: esp in prostate, spleen, kidney, and liver.
• - Disseminated infection: ∼ 55% of cases; 20% mortality rate. Manifests with fever and septic shock.
Diagnosis:
• Culture: the mainstay of diagnosis. Gram stain of sputum or abscess pus
• Imaging: Chest radiography: may show signs of acute pneumonia
rickettsiae
- all have 3 fts, what reaction is positive, mx for all
- 1 is slightly diff in presentaiton and negative reaction of above
causes of:
rocky mountain spotted fever
endemic typhus
epidermis typhus
Rash, headache + 1 or more eschars & history of foreign travel
• Weil-felix reaction +ve
• Tx: tetracyclines (doxycycline etc)
Except Q fever: pneumonia with no rash (coxiella burnetti)
• -ve weil-felix reaction
NOTES
= gram –ve obligate intracellular parasites
- Usually rash, headache and fever
Rocky mountain spotted fever • Rickettsia ricketsii • Tick • Headache + fever • Rash starts on wrists/ankles > centrally (maculopap > vasculitic) • Endemic to east coast of US
Endemic typhus
• R typhi
• Flea
• Rash starts central > peripheral
Epidemic typhys
• R prowazekii
• Human body louse
Ehrlichliosis: ehrlichia, tick.
when is p24 antigen test positive in HIV
when is HIV Ab
P24 antigen: positive from 1wk to 3-4wk after infection
HIV Ab: most dev at 4-6wk, 99% by 3months
• Most common and accurate. Screening ELISA and confirmatory western blot
syphilis - 2 optins for testing; one becomes neg after tx
causes of false positive (8)
Serological tests can be divided into:
• cardiolipin tests (not treponeme specific)
• treponemal-specific antibody tests
Cardiolipin tests
• syphilis infection > production of non-specific antibodies that react to cardiolipin
• EG VDRL (Venereal Disease Research Laboratory) & RPR (rapid plasma reagin)
• insensitive in late syphilis
• becomes negative after treatment
Treponemal specific antibody tests
• example: TPHA (Treponema pallidum HaemAgglutination test)
• remains positive after treatment
Therefore, following treatment for syphilis:
• VDRL becomes negative
• TPHA remains positive
Causes of false positive cardiolipin tests (positive VDRL, negative EIA/TPPA): - pregnancy - SLE, anti-phospholipid syndrome - TB - leprosy - malaria - HIV Other treponemal infections (yaws, pinta)
causes of genital ulcers (7) - diffs between them
Painful: herpes much more common than chancroid
Painless: syphilis much more common than LGV
NOTES
Genital herpes: multiple painful ulcers
Syphilis primary chancre: a painless ulcer
Chancroid: painful ulcer w sharply defined, ragged, undermined border + unilat painful LN enlargement
LGV: small painless pustule > ulcer. Then painful inguinal LN. then proctocolitis
Other causes of genital ulcers
- Behcet’s disease
- carcinoma
granuloma inguinale: Klebsiella granulomatis
amoebiasis cause
entamoeba histolytica
aspergilloma
- after CXR, Ix?
0 tx
1ST line immune response to aspergillus: macrophages
Tx voriconazole
CT: halo sign
If suspect aspergilloma from CXR, next test: serology for aspergillus precipitins
NOTES
= mycetoma (mass like fungal ball)
- Often in existing cavity in lung (TB, cancer, CF)
Usually asym
But can have cough, haemoptysis
Ix
- CXR: round opacity, crescent sign - High titres of aspergillus precipitins
trimethoprim mech of action, 2 SE and use in preg
Mechanism: interferes w DNA synth by inhibiting dihydrofolate reductase
- So can interact w methotrexate (also inh DHR)
Adverse effects
• myelosuppression
• transient rise in creatinine
Use in pregnancy
- Teratogenic risk in first trimester (folate antagonist) - Manufacturers advise avoid during pregnancy
DETAILS
More on Cr
trimethoprim competitively inh the tubular secretion of creatinine
-»_space; in a temporary increase which reverses upon stopping the drug
- It blocks the ENaC channel in the distal nephron > hyperkalaemic distal RTA (type 4)
mycoplasma
- complications (7)
- fts
- why is it important to recognise its atypical
- mx
- dx
Tx: doxycycline or macrolide
Ass w erythema multiforme, cold AI haemolytic anaemia
Notes
important to recognise atypical pneumonia: may not respond to penicillins or cephalosporins due to it lacking a peptidoglycan cell wall.
Features
• prolonged and gradual onset
• flu-like sym then dry cough
• CXR: bilateral consolidation
Complications
• cold agglutins (IgM): haemolytic anaemia, thrombocytopenia
• erythema multiforme, erythema nodosum
• meningoencephalitis, GBS and other immune-mediated neurological diseases
• bullous myringitis: painful vesicles on the tympanic membrane
• pericarditis/myocarditis
• GI: hepatitis, pancreatitis
• renal: acute glomerulonephritis
Investigations
- diagnosis is generally by Mycoplasma serology - positive cold agglutination test
easy rules of nrti v pi - what do they end in
- NRTIs: end in ‘ine’
- Pis: end in ‘vir’
NNRTIs: nevirapine, efavirenz
measles v rubella
Characteristic features of measles include
- a prodromal illness with fever, cough and conjunctivitis.
- Koplik spots, characteristic lesions of the oral mucosa, may appear during the prodromal phase before the rash.
○ However, while Koplik spots are specific to measles, they are not always present which can make the clinical diagnosis more difficult.
- The rash then starts behind the ears or on the face and spreads to the chest.
Measles can cause severe complications in pregnancy as it is a state of immunocompromise
- complications such as pneumonia are more common. - Public Health England recommends taking a thorough vaccination history at booking. - Post-exposure prophylaxis with human normal immunoglobulin is recommended for susceptible pregnant women who have been exposed to measles.
Rubella
Similar rash
No or much milder prodrome
Less high fever
fever, urticarial rash, hepatosplenomegaly, bronchospasm - likely dx
katayama fever - acute schiso
mycoplasma dx
serology
c.botulinum v tetani presentation
C.botulinum: flaccid paralysis
C.tetani: spastic paralysis
diphtheria - cause - fts Ix mx
PC: severe tonsillitis + neck swelling
Comps: myocarditis, rhythm abnormalities (esp heart block)
NOTES
Cause: gram positive, Corynebacterium diphtheriae
- produces exotoxin
- Transmitted via resp droplets
Diphtheria toxin > diphtheric membrane on tonsils (caused by necrotic mucosal cells)
- Systemic distribution can > necrosis of myocardial, neural and renal tissue
Possible presentations
• recent visitors to Eastern Europe/Russia/Asia
• sore throat w ‘diphtheric membrane’ - grey, pseudomembrane on the posterior pharyngeal wall
• bulky cervical lymphadenopathy (‘bull neck’)
• neuritis e.g. cranial nerves
• heart block - ass w poor prognosis
Ix: culture of throat swab: uses tellurite agar or Loeffler’s media
Management
• intramuscular penicillin
• diphtheria antitoxin
PCP
- mx?
- when do you need prophylaxis
- dx
- common comp
- extrapulm fts?
PCP: tx co-trimoxazole, add in steroids if hypoxic (eg pO2 <9)
Key bits
- Pneumothorax is a common comp - CD4 <200 = should have prophylaxis - Extrapulmonary manifestations are rare but incl: hepatosplenomeg, lymphadenopathy & choroid lesions - Def dx = BAL w silver stain
Notes
- Fts: SOB, dry cough, fever, v few chest signs - CXR usually bilat interstitial infiltrates but can get lobar consol or be normal - Sputum often negative - Often need BAL to see PCP (silver stain) - Need IV pentamidine in severe cases; or can give aerolised pentamidine (less effective and risk of pneumothorax)
Details
- Pneumocystic jiroveci = unicellular eukaryote - Co-trimoxazole = trimethoprim + sulfamethoxazole
crypto diarrhoea mx
supportive tx
may need nitazoxanide if immunosuppressed
immunosuppressed and exposed to chickenpox - mx?
If immunosuppressed and exposed to chickenpox: check for varicella Abs
- If negative (or can’t test): give VZ Ig
NOTES
Criteria to benefit from prophylaxis
1. Sig exposure to chickenpox or herpes zoster
2. Immunosuppressed (steroids longterm, methotrexate, other immunosup; neonates; pregnant)
3. No antibodies to varicella (NB shouldn’t delay getting Ig past 7ds of initial contact)
amphotericin B
- mech of actino
- SE (5)
- use
- Binds with ergosterol forming a transmembrane channel that leads to monovalent ion (K+, Na+, H+ and Cl) leakage > cell death
- SE: Nephrotoxicity, flu-like symptoms, hypokalaemia, hypomagnaseamia, hepatic failure
Used for systemic fungal infections
- SE: Nephrotoxicity, flu-like symptoms, hypokalaemia, hypomagnaseamia, hepatic failure
reversal of sleep wake cycle = what ID disease
Reversal of sleep wake cycle + behavioural changes = trypanosomiasis (african sleeping sickness
African trypanosomiasis (sleeping sickness) - fts mx spread by? where?
)
NOTES
African trypanosomiasis (sleeping sickness)
Gambiense in west africa
Rhodesiense east africa - more acute course
Both spread by tsetse fly
Fts
1. Painless SC nodule at site of infection (trypanosoma chancre) 2. Intermittent fever 3. Enlarged LNs (post cervical) 4. Later: CNS involved (somnolence, headache, mood change, meningoenceph)
Early: IV pentamidine or suramin
Late or cns: IV melarsoprol
American trypanosomiasis (chagas' disease) cause fts mx where
American trypanosomiasis (chagas' disease) Trypanosoma cruzi
Acute
- Most asym - But can see erythematous nodule at site of infection + periorbital oedema
Chronic
- Heart: myocarditis > dilated cardiomyopathy (apical atrophy) + arrthymias - GI: megaoesophagus, megacolon [dysphagia, constipation]
Mx:
- Acute: azole or nitro deriv EG benznidazole or nifurtimox
Chronic: tx the complications
lyme disease
- classic ft?
- other fts
- organism
- spread by
- Ix
- Mx
Cause: borrelia burgdorferi (spirochaete)
Spread: ticks
Fts
- Erythema migrans (bulls eye rash): 1-4wks after bite. Painless - Systemic fts: headache, lethargy, fever, arthralgia - Later: CV (heart block, peri/myocarditis), neuro (facial nerve palsy, meningitis, radicular pain)
Dx:
- Erythema migrans = clinical dx = start abx
- No EM: ELISA Abs to BB
○ If done within 4wks of syms and negative but still suspect it: repeat 4-6wk after 1st ELISA
○ If still suspect in syms for 12wks or more: immunoblot test
○ If ELISA positive or equivocal: immunoblot (western blotting)
Mx
- Early disease: doxy (if CI: amoxicllin) - Disseminated: ceftriaxone
Jarisch-herxheimer sometimes after start tx (fever, rash, tachycardia after 1st dose)
what disease can acute toxo present as in normal pts
· Acute toxo in normal pt can mimic acute EBV infection + should be suspected if EBV serology is negative
○ Need to pregnancy test due to risk of congenital toxo
○ Low fever, lymphoadenopathy w prominent cervical LNs, malaise, sore throat
Glandular fever: worst sore throat ever.
chikungunya
- how to differentiate from dengue (3)
- fts
- tx
- cause
- where from
NB: similar to dengue but:
- more joint pain - no rash usually - Normal bloods (dengue can cause low plts)
NOTES
Symptoms:
- severe joint pain + abrupt onset of high fever
- Others:
○ general flu-like illness of muscle ache, headache, and fatigue.
○ A rash may develop
○ swelling of the joints is not uncommon.
Similar to dengue but more joint pain which can be debilitating.
Treatment: Relief of symptoms.
DETAILS
· Alphavirus disease
· caused by infected mosquitoes.
· Africa, Asia and Indian subcontinent - few cases in Southern Europe recently
HIV post exposure prophylaxis
what drugs
how long for
when do you test
· HIV transmission rate from 1 needle stick 0.3%
· Viral load determines the risk of HIV transmission after a needle stick
· Oral ART for 4 weeks
Combo ART (tenofovir, emtricitabine and ritonavir/lopinavr), repeat HIV test in 12wk (as takes this long to dev Abs)
Man w gonorrhoea, tx w ceftriaxone, syms continue - cause
: co-existent infection w chlamydia
live attenutated vaccines (7)
who is CI from having them
- BCG, MMR, flu, oral rotavirus, oral polio, oral typhoid, yellow fever
Live attenuated vaccines are CI in pts w CD4 <200 (risk of vaccine-ass disease)
visceral leishmaniasis
fts
dx
where from
Visceral leishmaniasis (kala-azar)
• mostly caused by Leishmania donovani (visceral reaction to jason donovan)
• Mediterranean, Asia, South America, Africa
Fts
• fever, sweats, rigors
• massive splenomegaly. hepatomegaly
• poor appetite*, weight loss
• grey skin - ‘kala-azar’ means black sickness
• pancytopaenia secondary to hypersplenism
• the gold standard for diagnosis is bone marrow or splenic aspirate
*occasionally patients may report increased appetite with paradoxical weight loss
HIV drugs Types of drug - end bit of name integrase inh PI NRTI
Mech of drugs
• Integrase inhibitors
Types of drug • Gravir = integrase inh • 'Vir' = PI • 'ine' = NRTI • NNRTI = nevirapine, efavirenz
Mech of drugs
• Integrase inhibitors (gravirs): block the enz that inserts the viral genome into the DNA of the host cell
staph aureus pneumonia
- 2 characteristic fts
cavitating lesions when it causes pneumonia
After flu
HUS presentation
- bacterial cause
E. coli O157:H7 causes HUS
- Bloody diarrhoea, acute renal failure w high urea and hamolytic anaemia (schistocytes on blood film)
NOTES
E. coli O157:H7
- severe, haemorrhagic, watery diarrhoea
- high mortality rate
- can be complicated by haemolytic uraemic syndrome
often spread by contaminated ground beef.
most common comp from repeated gonorrohea infection
infertility due to PID
rabies
- fts
- mx if immunised, if not immunised
Features
- prodrome: headache, fever, agitation - hydrophobia: water-provoking muscle spasms - hypersalivation - Negri bodies: cytoplasmic inclusion bodies found in infected neurons
Following an animal bite in at-risk countries:
- the wound should be washed
- if already immunised: 2 further doses of vaccine
- not previously immunised: human rabies Ig + full course of vaccination.
○ If possible, the dose should be administered locally around the wound
DETAILS
- viral disease - causes an acute encephalitis - RNA rhabdovirus (specifically a lyssavirus) - has a bullet-shaped capsid
Cause
- Most: dog bites - But can be transmitted by bat, raccoon and skunk bites.
Following a bite the virus travels up the nerve axons towards the CNS in a retrograde fashion.
Mortality
- 25,000-50,000 people across the world each year - The vast majority of the disease burden falls on people in poor rural areas of Africa and Asia. - Children are particularly at risk.
‘no risk’ of developing rabies following an animal bite in the UK and the majority of developed countries.
If untreated the disease is nearly always fatal.
dengue fever - classic fts - bloods (3) - dx (3 optins) mx
retro-orbital headache, fever, facial flushing, rash, thrombocytopenia in returning traveller
Investigations
• Bloods: leukopenia, thrombocytopenia, raised aminotransferases
• diagnostic tests
○ serology
○ nucleic acid amplification tests for viral RNA
○ NS1 antigen test
Treatment
- entirely symptomatic e.g. fluid resuscitation, blood transfusion etc - no antivirals are currently available
MORE
Dengue fever
• fever
• headache (often retro-orbital)
• myalgia, bone pain and arthralgia ('break-bone fever')
• pleuritic pain
• facial flushing (dengue)
• maculopapular rash
• haemorrhagic manifestations e.g. positive tourniquet test, petechiae, purpura/ecchymosis, epistaxis
• 'warning signs' include:
○ abdominal pain
○ hepatomegaly
○ persistent vomiting
○ clinical fluid accumulation (ascites, pleural effusion)
Severe dengue (dengue haemorrhagic fever)
• A form of DIC resulting in:
○ thrombocytopenia
○ spontaneous bleeding
• 20-30% of these go on to dev.dengue shock syndrome (DSS)
cholera
- cause
- fts (3)
- mx
Cause: Vibro cholerae - Gram negative bacteria Features • profuse 'rice water' diarrhoea • dehydration • hypoglycaemia Management • oral rehydration therapy antibiotics: doxycycline, ciprofloxacin
strep pyogenes causes 8 diseases
Causes: rheumatic fever, scarlet fever, post-strep GN, erysipelas, impetigo, cellulitis, type 2 nec fasc, pharyngitis/tonsillitis
meningeal TB
RIPE for 12mos + prednisolone
fts of severe falciparum
& mx
what ft may indicate co-existent bacterial infection
Features of severe • schizonts on a blood film • parasitaemia > 2% • acidosis • temperature > 39 °C • severe anaemia • comps
Complications • cerebral malaria: seizures, coma • acute renal failure: blackwater fever, secondary to intravascular haemolysis • ARDS • hypoglycaemia DIC
Severe falciparum malaria
- parasite counts >2% usually need parenteral treatment irrespective of clinical state
- IV artesunate
- if parasite count > 10% consider exchange transfusion
shock may indicate coexistent bacterial septicaemia - malaria rarely causes haemodynamic collapse
tetanus mx
If had 5 doses of tetanus vaccine with last one <10y ago: do NOT need vaccine booster or Ig (no matter how bad the wound is)
Full course of vaccines, last dose >10y ago:
- Tetanus prone wound: 1 more dose of vaccine - High risk: 1 more vaccine dose & Ig
If vaccine history unknown/incompolete:
- All get booster dose
If tetanus prone or high risk: also give Ig
disseminated gonorrhoea fts (3)
· Disseminated infection = tenosynovitis, migratory polyarthritis + dermatitis
shigella abx and indiciations for them
cipro
• antibiotics if severe disease, who are immunocomp or with bloody diarrhoea - cipro
e.coli causes 3 types of illness
- diarrhoeal illnesses
- UTIs
- neonatal meningitis
