ARF/RHD Guidelines

Question 1

Burden of ARF and RHD

Answer 1

• most commonly seen in 5-14 year olds - females are more likely to be diagnosed with ARF - 1 in 5 patients will have a recurrent episode of ARF within 10 years of their first episode - 50% of patients will progress to RHD within 10 years after their initial ARF (if severe or recurrent ARF)

Question 2

What are the 2 main social determinants of ARF?

Answer 2

1. Overcrowded conditions 2. Limited access to facilities to wash people, clothes and bedding Both increase the risk of strep A infections

Question 3

Which bacterial causes ARF?

Answer 3

Group A streptococcus - human only infection, nil animal reservoirs

Question 4

What are the 9 health living practices and their association with group A strep?

Answer 4

1. Washing people (strong) 2. Washing clothes and bedding (medium) 3. Remove wastewater (weak) 4. Improve nutrition and ability to store and cook food (weak) 5. Reduce overcrowding (strong) 6. Reduce negative affects of animals i.e. cuts/skin damage and scabies (medium - indirect) 7. Reduce health impact of dust (weak) 8. Controlling temp of living environment (weak) 9. Reduce hazards that cause trauma (mediuM0 These were developed in 19080s by Nganampa Health Council in South Australia.

Question 5

Describe primary prevention of ARF.

Answer 5

• aim is to interrupt link between strep A infection and abnormal immune response to strep A that causes ARF - this is done by early identification of strep A infections - treatment of strep A sore throat with Abx can reduce development of ARF by up to two-thirds

Question 6

How common is strep A in relation to sore throats?

Answer 6

• associated in up to 37% of sore throats - present in 10-40% of children with sore throats - associated in up to 82% if impetigo episodes

Question 7

Describe the high risk group for ARF.

Answer 7

• living in ARF endemic setting - Aboriginal and/or Torres Strait Islander people living in rural and remote settings - Aboriginal and/or Torres Strait Islander, Maori and/or Pacific Islander people living in metro households affected by overcrowing or lower SES - personal history of ARF/RHD and aged <40

Question 8

Recommended Abx for strep throat/tonsillitis?

Answer 8

1) Benzathine benzylpenicillin (BPG) - deep IM, once off dosing 2) Phenoxymethylpenicillin - PO, for 10 days 3) Cefalexin –> if hypersensitive to penicillin (rash) - PO for 10 days 4) Azithromycin –> if anaphylactic to penicillin - PO for 5 days

Question 9

Dosing for benzathine benzylpenicillin for strep throat.

Answer 9

<10kg: 450,000 units (0.9ml) 10-<20kg: 600,000 units (1.2ml) >20kgL 1,200,000 units (2.3ml)

Question 10

Dosing for phenoxymethypenicillin for strep throat.

Answer 10

Child: 15mg/kg up to 500mg BD Adult: 500mg BD

Question 11

Recommended antibiotic treatment for strep A skin sores in children with >1 purulent or crusted sores

Answer 11

1) Trimethoprim/sulfamethoxazol > 4mg/kg/dose of trimethoprim, BD for 3 days OR 2) benzathine benxylpenicillin (as per treatment for strep throat)

Question 12

Signs suggestive for strep throat

Answer 12

Fever Swollen/enlarged tonsils Erythematous tonsils with exudate Enlarged and tender cervical lymphadenopathy Absence of cough (I.e. Centor Criteria)

Question 13

What are the diagnostic classifications of ARF?

Answer 13

• definite ARF/definite recurrence - probable ARF/probable recurrence - possible ARF/possible recurrence

Question 14

How soon should a patient with confirmed ARF be admitted/get a TTE?

Answer 14

Within 24-72 hours

Question 15

ECG findings in ARF

Answer 15

• first degree heart block most common - second degree HB, complete HB and accelerated junctional rhythms occur in 8% of cases of ARF

Question 16

Criteria for diagnosis of “definite initial episode” of ARF?

Answer 16

2 major manifestations + evidence of preceding strep A OR 1 major + 2 minor manifestation + evidence of preceding strep A

Question 17

Criteria for diagnosis for recurrent episodes in ARF in patients with known ARF/RHD?

Answer 17

2 major manifestations + evidence of preceding strep A OR 1 major + 2 minor manifestation + evidence of preceding strep A OR 3 minor manifestations + evidence of preceding strep A

Question 18

What are the major manifestations of ARF? (5)

Answer 18

1. Carditis 2. Polyarthritis 3. Sydenham chorea 4. Erythema marginatum 5. Subcutaneous nodules ** note in high risk populations aseptic monoarthritis or polyarthralgia are classified as MAJOR manifestations

Question 19

What are the minor manifestations of ARF? (4)

Answer 19

1. Fever > 38.5 2. Monoarthralgia, polyarthralgia, aseptic monoarthritis 3. ESR > 30 OR CRP >30 4. Prolonged PR interval on ECG

Question 20

Define evidence of preceding strep A infection serologically.

Answer 20

• elevated or rising antistreptolysin O or other strep antibody - positive throat culture - or positive rapid antigen/nucleic acid test for strep A infection

Question 21

What are the upper limits of normal PR interval in a) 3-11 year olds b) 12-16 year olds c) >17 year olds

Answer 21

a) 0.16 b) 0.18 c) 0.2

Question 22

Is ARF a notifiable disease?

Answer 22

Yes All causes should be notified to the local Disease Control Unit or Public Health Unit and registered with the RHD control program

Question 23

What are the two most common clinical manifestations of ARF and their differences?

Answer 23

• Acute febrile illness: onset 2-4 weeks post GAS - Neurological illness: 25-30% of cases, later onset 2-6 mpst post GAS

Question 24

Define primordial, primary, secondary and tertiary prevention of ARF/RHD.

Answer 24

• primordial: addessing social determinants of health
• primary: treatment of GAS infections with penicillin
• secondary: IM penicillin G to prevent recurrent ARF and RHD
• tertiary: treatment of established RHD

Question 25

Which valve is most commonly involved in RHD?

Answer 25

Mitral

Question 26

Criteria for pathological mitral regurg on US.

Answer 26

Seen in two views

Jet length ≥ 2cm

Peak velocity ≥ 3 m/s

Pan-systolic jet in at least one envelope

Question 27

What is the aim of secondary ARF prophylaxis?

Answer 27

• aim is to provide consistent and regular antibiotics to patients who have ARF or RHD to prevent furture GAS infections and recurrence of ARF
• relies on IM injections of benzathine benzylpenicilling (BPG) every 28 days
• if possible ARF needs to be done for 12 months
• if definite ARF need prophylaxis for minimum for 5 years after most recent episode of until age 21 (whichever is longer)
• if known RHD need to continue prophylaxis for at least 10 years after the most recent episode of ARF, or if nil documented ARF at least 5 years after diagnosis if < 35

Question 28

Anticoagulation in RHD.

Answer 28

• NOAC preferred in patients with RHD and AF, except in patients with moderate or severe mitral stenosis
• warfarin indicated if moderate to severe mitral stenosis

Question 29

Table of priority cliassifcation and recommended follow up for RHD patients.

Answer 29

Question 30

Definition of severe MR

Answer 30

LVEF <60%

LVESD >40mm OR

New onset AF OR

New PASP >50mmHg

or Child with enlarged heart size

Question 31

Which surgical procedures would require antibiotics for infective endocarditis prophylaxis?

Answer 31

• All patients witH RHD need to be considered for prophylactic Abx
• Dental procedures in volving gingiva or perforation or oral mucosa
• Dermatological and MKS procedures involving infections
• ENT: tonsillectomt or adenoidectomt or invastive respiratory tract surgeries with established infections
• GI/GU procedures: only if surgical Abx are required

Question 32

Management of RHD in pregnancy.

Answer 32