Rheumatic Fever, Lyme Disease

Question 1

DOC for treating group A streptococcal infection in rheumatic fever with dose and route

Answer 1

Penicillin V: 500mg x 2 orally for 10 days

250 mg for children under 27kg

Question 2

Other antibiotics for rheumatic fever

Answer 2

Amoxicillin: 50mg/kg daily for 10 days

Single Dose: Benzathine penicillin G: 1,2 mill U IM (600K U for children under 27kg)

Question 3

Treatment of arthritis, arthralgia and fever in rheumatic fever
Treatment in case of severe carditis
Treatment of Chorea

Answer 3

Aspirin: 50-60 mg/kg/day, up to max 80-100 mg/kg/day (4-8 g/d in adults) in 4-5 divided doses

Naproxen: 10-20 mg/kg/day: alternative to aspirin, twice
daily dosing

Carditis: Prednisone: 1-2 mg/kg/day for few days (max 3 weeks). Diuretics or Digoxin if necessary can also be given. If HF is severe and no response to treatment; consider surgery (valve replacement).

Chrorea: Mild and calm enviroment, Haloperidol -2-12 mg/day PO

Question 4

Secondary prophylaxis of rheumatic fever

Answer 4

Benzathine penicillin G (1.2 million units, or 600,000 units if ≤27 kg) delivered every 4 weeks. It can be given every 3 weeks, or even every 2 weeks, to persons considered to be at particularly high risk

Oral penicillin V (250 mg) can be given twice daily instead but is less effective than benzathine penicillin G. Penicillin-allergic patients can receive erythromycin (250 mg) twice daily.

Duration of secondary prophylaxis is determined by many factors; duration of last ep of ARF, age, severity of RHD

Question 5

Differential diagnosis of rheumatic fever

Answer 5

Babesiosis
Ankylosing spondylitis and rheumatoid arthritis
Cellulitis
Ringworm
Erythema multiforme
Septic arthritis

Question 6

What is required to confirm diagnosis of rheumatic fever?

Answer 6

Jones criteria; 2 major or 1 major + 2 minor. Evidence of gr. a strep infection

Question 7

Major Criteria (jones)

Answer 7

Carditis
Arthritis
Chorea
Erythema marginatum
SC nodules

Question 8

Minor Criteria (jones)

Answer 8

Low-risk populations/Moderate- and high-risk:

Polyarthralgia/Monoarthralgia
Fever >38.5/Fever >38
ESR>60 within the first hour/ESR>30
CRP>3.0 mg/dL
Prolonged PR interval, after accounting for age variability

Question 9

Aspirin - MoA

Answer 9

Nonselective COX inhibitor. Inhibit prostaglandin synthesis

Question 10

Aspirin - Adverse effects

Answer 10

GI bleeding, peptic ulcers
Renal and hepatic dysfunction
Hyperkalemia

Question 11

Aspirin - Contraindications

Answer 11

Virus infected children (cause reye syndrome)

Previous severe hypersensitivity to salicylates (cross-sensitivity)

Question 12

Aspirin - Interactions

Answer 12

Inhibit renal excretion of lithium.

Reduced clearance of aminoglycosides & methotrexates.

Interfere with antihypertensive effect of: diuretics, β-adrenoceptor antagonists, angiotensin inhibitors & others.

Potassium-sparing diuretics: hyperkalemia

Question 13

Lyme disease treatment for men and nonpregnant women

Answer 13

Doxycycline: 100 mg x 2 for 14 days (Also for arthritis, carditis, ACA –> 21 days)
Penicillin: 1g x 4 for 14 days

Question 14

Lyme disease treatment for pregnant/nursing women or people with allergy

Answer 14

Azithromycin: 1g first day once, then 500mg x 1 next 4 days.

Question 15

Duration of lyme disease therapy

Answer 15

Localized skin infection: 14 days
Early disseminated infection: 21 days
Acrodermatitis: 30 days
Arthritis: 30-60 days

Question 16

Lyme disease treatment for neurologic abnormalities and high degree AV block

Answer 16

Ceftriaxone: 2g IV for 14-28 days

Question 17

Doxycycline - MoA

Answer 17

Protein synthesis inhibitor

Question 18

Doxycycline - Adverse effects

Answer 18

Discoloration of teeth and hypoplasia of the enamel in pregnant women and children under 8 years

Nephrotoxicity and Hepatotoxicity (increased risk in pregnant women)(fatty degeneration)

Photosensitivity
Erythema, sunburn

Nausea, vomiting, anorexia

Question 19

Doxycycline - Contraindications

Answer 19

Children under 8

Pregnant women

Question 20

Doxycycline - Interactions

Answer 20

Ca, Al, Fe: reduced bioavailability

Potentiate nephrotixicity with aminoglycosides

Question 21

Rheumatic Fever - Diagnosis

Answer 21

Evidence of gr A strep infection:
Throat swab culture
Rapid antigen test from throat swab
Serologic tests:
- Anti-streptolysin O (ASO) titer: increased
- Anti-DNAse B: high in gr A strep skin infections
Imaging:
- ECG: increased P-R interval, AV block
- Echo: determine severity of carditis, may see leaflet thickening
Other:
ESR, CRP, CBC
Check for major and minor jones criteria
Microscopy: Aschoff body
Physical exam:
Auscultation: friction rub (pericarditis), murmurs (mitral regurgitation), Softening of 1st heart sound

Question 22

Prednisone - MoA

Answer 22

Glucocorticoid, reduces inflammation

Question 23

Prednisone - Adverse effects

Answer 23

Cushing- appearance. Hirsutism, weight gain, acne, glucose intolerance, hypertension

Question 24

Prednisone - Interactions

Answer 24

Mifeprostone; decreases the efficiency of prednisone

Question 25

Prednisone - Contraindication

Answer 25

Hypertension, Osteoporosis, Psychosis, peptic ulcers

Question 26

Haloperidol - MoA

Answer 26

Typical antipsychotic agent, D2 antagonists

Question 27

Haloperidol - Adverse effects

Answer 27

Extrapyramidal: Rigidity, bradykinesia, tremor, akathisia

Question 28

Haloperidol - Interactions

Answer 28

Barbiturates and carbamazepine decreases serum levels. Quinidine increases serum levels.

Question 29

Haloperidol - Contraindication

Answer 29

Dementia with Lewy bodies, Allergy, intox with alcohol

Question 30

Duration of prophylaxis for Rheumatic fever

Answer 30

Rheumatic fever without carditis: 5 years or until 21 years of age
RF with carditis: 10 y or until 21
RF with valvular disease: 10 y or until 40 y

Question 31

Lyme disease - Diagnosis

Answer 31

Serologic evidence combined with clinical picture
If EM is present –> Diagnosis is made, start therapy
IgM antibody or a rising titer of IgG (taken from blood or CSF) with ELISA; positive test –> Confirm with Western blot analysis
PCR: joint fluid (synovial fluid); shows infiltration og lymphocytes and plasma cells, skin (ACA)
CSF (neuroborelliosis): lymphocytes, moderate/high proteins, oligoclonal bands. LP should be one for all pts with facial paralysis.

Question 32

Ceftriaxone - MoA

Answer 32

Inhibits bacterial cell wall synthesis. 3rd gr cephalosporin

Question 33

Ceftriaxone - Adverse effects

Answer 33

Hypersensitivity, skin rash, hemolytic anemia, interstitial nephritis, tubular necrosis

Question 34

Ceftriaxone - Interactions

Answer 34

Probenecid increases renal secretion and increases serum concentrations

Question 35

Ceftriaxone - Contraindication

Answer 35

Renal failure, allergy to cephalosporins, hypoalbuminemia

Question 36

Prophylaxis treatment of Lyme

Answer 36

Doxycycline - 200 mg PO within 72 h