Acute Rheumatic Fever and Rheumatic Heart Disease Flashcards
demographic features of acute rhuematic fever
5-14yo
females diagnosed more frequently
ethnicity - indigenous australians, maori, pacific islanders, migrants from low/middle income countries
high risk of recurrance
culture of group A strep
historic gold standard
most useful for acute infections, especially invasive GAS
less useful for post-infectious complications
serology for group A strep is most useful for
most useful for the diagnosis of post-infectious complications
major manifestations of acute rhuematic fever
arthritis
carditis
chorea
subcutaneous nodules
erythema marginatum
arthritis in acute rheumatic fever
most common presentation
arthritis: swollen, hot joint, with pain in movement
arthralgia: pain on joint movement, no joint swelling or heat
classically: asymmetric, migratory, large joints
very responsive to NSAIDs
carditis in acute rheumatic fever
2nd most common clinical feature
predominantly inflammation of the endocardium (as opposed to myocardium/pericardium) - especially left side valvulitis
clinical features of carditis
often subclinical
clinical features may include:
- cardiac murmur
- cardiac enlargement
- cardiac decompensation
- pericardial friction rub or effusion
investigations for carditis
ECG: prolonged PR interval
Echo: valvulitis
role of echocardiogram in valvulitis
define the severity of mitral aortic and/or tricuspid regurgitation
define the severity of mixed valve disease (mixed stenotic and regurgitant)
identify subclinical evidence of rheumatic valve damage
visualse valvular anatomy and define meechanism of reegurgitation (prolapse, flail leaflet, annular dilatation etc)
role of echocardiogra, in cardiac function
assess left ventricular size and function
chorea as a clinical feature of acute rheumatic fever
third most common clinical feature
if other causes of chorea are excluded, chorea is diagnostic for ARF
can occur after a period of latency
the most likely major manifestation to occur
clinical signs of chorea
milkmaids hands - rhythmic squeezing of examiners hands
spooning - flexion of the wrists and extension of the fingeer when the hands are extended
pronator sign - turning outward of the arms and palms when help above the head
inability to maintain protrusion of the tongue
subcutenous nodules
rare
highly specific for ARF
strong association with carditis
crops of small, round, painless nodules
usually on extensor surfaces - over the lebows, wrists, knees, ankles, achillies tendon, occiput and posterior spinal processes of the vertebrae
erythema marginatum
eextremely rare
diifficult to see in dark skinned populations
occurs as circular patterns of bright ppink macules or pappules on the trunk and proximal extremities, face usually spared
not pruritic or painful
evanescent - waxes and wanes during the course of a day
not affected by NSAIDs, steroids
can recur for weeks/months
investigations for acute rheumatic fever
ECG, Echo, FBC, ESR, CRP, strep serology (ASOT, antiDNAB)
dependant on context: throat swab, skin sore swab, blood culture, synovial fluid aspirate
natural history of rheumatic heart disease
