Rheumatic Fever, Lyme Disease Flashcards
DOC for treating group A streptococcal infection in rheumatic fever with dose and route
Penicillin V: 500mg x 2 orally for 10 days
250 mg for children under 27kg
Other antibiotics for rheumatic fever
Amoxicillin: 50mg/kg daily for 10 days
Single Dose: Benzathine penicillin G: 1,2 mill U IM (600K U for children under 27kg)
Treatment of arthritis, arthralgia and fever in rheumatic fever
Treatment in case of severe carditis
Treatment of Chorea
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
Secondary prophylaxis of rheumatic fever
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
Differential diagnosis of rheumatic fever
Babesiosis Ankylosing spondylitis and rheumatoid arthritis Cellulitis Ringworm Erythema multiforme Septic arthritis
What is required to confirm diagnosis of rheumatic fever?
Jones criteria; 2 major or 1 major + 2 minor. Evidence of gr. a strep infection
Major Criteria (jones)
Carditis Arthritis Chorea Erythema marginatum SC nodules
Minor Criteria (jones)
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
Aspirin - MoA
Nonselective COX inhibitor. Inhibit prostaglandin synthesis
Aspirin - Adverse effects
GI bleeding, peptic ulcers
Renal and hepatic dysfunction
Hyperkalemia
Aspirin - Contraindications
Virus infected children (cause reye syndrome)
Previous severe hypersensitivity to salicylates (cross-sensitivity)
Aspirin - Interactions
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
Lyme disease treatment for men and nonpregnant women
Doxycycline: 100 mg x 2 for 14 days (Also for arthritis, carditis, ACA –> 21 days)
Penicillin: 1g x 4 for 14 days
Lyme disease treatment for pregnant/nursing women or people with allergy
Azithromycin: 1g first day once, then 500mg x 1 next 4 days.
Duration of lyme disease therapy
Localized skin infection: 14 days
Early disseminated infection: 21 days
Acrodermatitis: 30 days
Arthritis: 30-60 days
Lyme disease treatment for neurologic abnormalities and high degree AV block
Ceftriaxone: 2g IV for 14-28 days
Doxycycline - MoA
Protein synthesis inhibitor
Doxycycline - Adverse effects
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
Doxycycline - Contraindications
Children under 8
Pregnant women
Doxycycline - Interactions
Ca, Al, Fe: reduced bioavailability
Potentiate nephrotixicity with aminoglycosides
Rheumatic Fever - Diagnosis
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
Prednisone - MoA
Glucocorticoid, reduces inflammation
Prednisone - Adverse effects
Cushing- appearance. Hirsutism, weight gain, acne, glucose intolerance, hypertension
Prednisone - Interactions
Mifeprostone; decreases the efficiency of prednisone
Prednisone - Contraindication
Hypertension, Osteoporosis, Psychosis, peptic ulcers
Haloperidol - MoA
Typical antipsychotic agent, D2 antagonists
Haloperidol - Adverse effects
Extrapyramidal: Rigidity, bradykinesia, tremor, akathisia
Haloperidol - Interactions
Barbiturates and carbamazepine decreases serum levels. Quinidine increases serum levels.
Haloperidol - Contraindication
Dementia with Lewy bodies, Allergy, intox with alcohol
Duration of prophylaxis for Rheumatic fever
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
Lyme disease - Diagnosis
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.
Ceftriaxone - MoA
Inhibits bacterial cell wall synthesis. 3rd gr cephalosporin
Ceftriaxone - Adverse effects
Hypersensitivity, skin rash, hemolytic anemia, interstitial nephritis, tubular necrosis
Ceftriaxone - Interactions
Probenecid increases renal secretion and increases serum concentrations
Ceftriaxone - Contraindication
Renal failure, allergy to cephalosporins, hypoalbuminemia
Prophylaxis treatment of Lyme
Doxycycline - 200 mg PO within 72 h
