Case 12: extra and HIV Flashcards
1
Q
Shingles vaccine
A
- Offered to all patients aged 70-79 years
- is live-attenuated and given sub-cutaneously
- Don’t give if immunocompromised
2
Q
Shingles progression
A
- Prodrome: acute neuralgia (tingling, burning pain with enlarged lymph nodes(typically 2-3 days)
- Infectious: rash (affects single dermatome in a band like distribution) rarely crosses the midline, pain where the rash is (7-10 days)
- Resolution: vesicles crust other and take a month to disappear
3
Q
Chicken pox pathophysiology
A
- spread via the respiratory route
- can be caught from someone with shingles
- infectivity = 4 days before rash, until 5 days after the rash first appeared*
- incubation period = 10-21 days
4
Q
Chicken pox clinical features
A
- Fever initially
- itchy, rash starting on head/trunk before spreading. Initially macular then papular then vesicular
- Generalised pruritic rash
- Macular -> Papular -> Vesicular -> Crusted
- systemic upset is usually mild
- Usually mild in healthy children, more severe if immunocompromised, neonates and adults
5
Q
Management of chicken pox
A
- Calamine lotion
- School exclusion:Advise that the most infectious period is 1–2 days before the rash appears, but infectivity continues until all the lesions are dry and have crusted over (usually about 5 days after the onset of the rash).
- Immunocompromised patients and newborns with peripartum exposure should receivevaricella zosterimmunoglobulin (VZIG). If chickenpox develops then IV aciclovir should be considered
6
Q
Infective endocarditis
A
An infection of the endocardial surface of the heart including one or more of the valves. Rare and life threatening
7
Q
IE pathophysiology
A
Turbulent blood flow causes damage to the smooth endothelium, causes accumulation of platelets, fibrin, leukocytes which can be infected by circulating microorganisms forming a vegetation.
8
Q
Risk factors for IE
A
- Age >60years, Male
- Intravenous drug use particularly increased risk of right sided IE
- Intravascular lines
- Chronic haemodialysis (usually have a fistula or a long-term haemodialysis catheter which can become infected)
- Immunosuppression
- Recentdental or surgical procedure
- Cardiac factors: history of prior IE, prosthetic heart valve, cardiac devices (pace maker) structural heart disease (valvular or congenital)
- Rheumatic heart disease with mitral valve affected
9
Q
Causes of IE
A
- Staphylococcusaureus (most common cause of IE, associated with IVDU)
- Viridians group streptococcus(more prevalent among some older populations and community-acquired IE, recent dental extraction)
- Enterococci (3rd highest cause, linked to health care contact and recurrent UTI’s)
- Streptococci bovis(high association with bowel cancer)
10
Q
Unusual causes of IE
A
- Coxiella burnetii(the causative agent of Q fever, associated with abattoirs / livestock)
- Bartonella spp (associated with alcoholism or homelessness)
- Brucella spp (travel to the Middle East or the Mediterranean or consumption of unpasteurized dairy products)
- Bartonella henselae (contact with cats )
- Aspergillus spp. (extensive health care contact in a patient with a prosthetic valve
11
Q
Clinical manifestations of IE
A
- Fever- with chills, anorexia and weight loss
- Non-specific: malaise, arthralgia, night sweats and abdominal pain
- Heart murmurs: usually in left IE
- Cutaneous manifestations: Petechiae and splinter haemorrhages
- Specific to IE: Janeway lesions (non-tender), Osler nodes (tender), Roth spots (haemorrhagic retinal lesions with a pale centre)
- Long standing disease: finger clubbing and Splenomegaly
12
Q
Pulmonary septic emboli
A
Is the most common presentation of isolated right-sided IE (10% of all cases of IE). Presents with a cough, dyspnoea, haemoptysis or pleuritic chest pain.
13
Q
Investigations or IE
A
- Blood cultures: 3 samples from different sites with a gap of 1-6hr. Must be taken before antibiotics. 2 sets within 1hr if septic and starting abx. Dont wait till temperature spike.
- Bloods: FBC, CRP, ESR, U&E, LFT
- Transthoracic echocardiogram (TTE): first line investigation
- Transoesophageal echocardiogram (TOE): Do if TTE is negative
- ECG
- CXR: to look for pulmonary septic emboli, congestive heart failure or ay abscess’s
- CT scan (thoracic, abdominal and pelvis): for metastatic infections
- Special investigations for prosthetic heart valves: 18F-FDG PET/CT, SPECT-CT
14
Q
Modified Duke criteria
A
- Used to diagnose infective endocarditis based on either Clinical or Pathological criteria
- Clinical criteria: Requires One major plus three minor criteria or five minor criteria
15
Q
DUKE’s major criteria
A
- Persistently positive blood cultures (Of organisms which cause IE) , cultures must be separated in time
- Imaging findings (echocardiogram) of endocardial involvement : vegetation, abscess, Prosthetic valve dehiscence, new regurgitation
16
Q
Duke’s pathological criteria
A
- Microorganisms demonstrated by culture or histology of a vegetation or emboli
- Vegetation or abscess confirmed by histology to be active endocarditis
- Both require surgical intervention: either culture of histology
17
Q
Duke’s minor criteria
A
- Predisposition (heart disease) or IVDU
- Fever >38
- Vascular phenomena (Janeway lesions)
- Immunological phenomena (Osler nodes, Roth spots)
- Microbiological phenomena
- PCR
- Echocardiographic findings
18
Q
Managing IE
A
- IV Antibiotics (i.e. amoxicillin and optional gentamicin): can delay based on blood culture results if stable
- HACEK organisms can be treated with Ceftriaxone
- Antibiotics are given for 4 weeks in native heart valves and 6 weeks in prosthetic
- Remove source of infection: i.e. intravascular catheter, intracardiac device, arteriovenous fistula. May need dental evaluation
- Colonoscopy: when group D streptococci is found on culture
- Valve surgery
19
Q
Different antibiotics for IE
A
- If stable wait for blood culture results
- Native valve: Amoxicillin with optional gentamicin
- Native valve with sepsis: Vancomycin and gentamycin
- Prosthetic valve: Vancomycin, Gentamycin and Rifampicin
- HACEK (gram negative): Ceftriaxone or Amoxicillin, Gentamicin for first 2 weeks, alternative is Ciprofloxacin
20
Q
When is valve surgery indicated
A
- IE-associated valvular regurgitation/dysfunction
- Associated complications i.e. septic emboli
- Heart failure
- Intracardiac abscess or large vegetations (>10mm)
- Infections not responding to antibiotics (fungal or antimicrobial resistant) 7 day cut off
