Rheumatic Fever (RF)

• Rheumatic Fever (RF) is a diffuse inflammatory condition of autoimmune origin.
• RF primarily affects the connective tissue of the heart, joints, subcutaneous tissues, brain, and blood vessels.

Incidence

• Rheumatic fever is a major global health problem, affecting approximately 100 in 100,000 children under 18.
• It is more prevalent in underdeveloped countries where medical care is limited, and children live in poverty with unsanitary conditions.
• In developing countries, rheumatic fever is the predominant cause of acquired childhood cardiomyopathy.
• In Egypt, rheumatic fever affects young children, with 10% of cases experiencing their first attack before 15 years of age.
• It affects 8-9 per 10,000 children between ages 6 and 12.

Cause

• RF develops in children and adolescents following group A beta-hemolytic streptococcal (GABHS) pharyngitis.
• Infections of the pharynx can initiate or reactivate rheumatic fever.
• Molecular mimicry between streptococcal and human proteins involves B and T cells, causing infiltration of the heart by T cells.
• An increased production of inflammatory cytokines is the final mechanism.
• This autoimmune reaction damages cardiac tissue in rheumatic heart disease (RHD).
• Streptococcal antigens, structurally similar to those in the heart, include:
  • Hyaluronate in the bacterial capsule
  • Cell wall polysaccharides
  • Membrane antigens that share epitopes with the sarcolemma and smooth muscle
• Decreased levels of regulatory T-cells are associated with rheumatic heart disease and increased severity.

Risk Factors

• Risk factors include poor, crowded areas, undernutrition, and lack of healthcare.
• Lack of awareness of the disease is also a risk factor.
• Children do not develop immunity to streptococcal infections, which can recur, leading to recurrent rheumatic fever.

Pathophysiology

• RF develops in children and adolescents following pharyngitis with GABHS (Streptococcus pyogenes).
• The organisms attach to the epithelial cells of the upper respiratory tract.
• They produce enzymes that damage and invade human tissues.
• After a 2-4 day incubation period, the invading organisms cause an inflammatory response with 3-5 days of sore throat, fever, malaise, headache, and elevated leukocyte count.
• A small percentage of patients develop rheumatic fever weeks after a sore throat resolves.
• Only pharyngeal infections initiate or reactivate rheumatic fever.
• Direct contact with oral or respiratory secretions transmits the organism, with crowding enhancing transmission.
• Patients remain infected and act as a reservoir for infecting others.
• Severe scarring of the valves develops months to years after acute rheumatic fever, with recurrent episodes causing progressive damage.
• The mitral valve is most commonly affected (65-70% of patients)
• The aortic valve is affected second most commonly (25%).

Clinical Manifestations

• Major manifestations:
  • Migratory polyarthritis: Inflammation of joints (tender, warm, erythematous) moving rapidly, lasting less than 1 week per joint.
  • Carditis: Inflammation of the endocardium, myocardium, and pericardium, diagnosed via cardiac murmur.
  • Other signs include cardiac enlargement/failure, or a pericardial friction rub.
  • Chorea: Involuntary, jerky movements of the legs, arms, and face, with speech impairment and emotional lability due to CNS involvement (Sydenham’s chorea).
  • It is more common in girls
  • Erythema Marginatum: Red, painless skin lesions that start as flat or slightly raised macules over the trunk.
  • Subcutaneous nodules: Small, non-tender lumps attached to tendon sheaths of joints and bony prominences.
• Minor manifestations:
  • History of previous RF
  • Arthralgia (joint pain)
  • Fever
  • Elevated C-reactive protein and erythrocyte sedimentation rate
  • Changes in ECG

Diagnosis

• Diagnosis of acute rheumatic fever is established by the Jones criteria.
• This requires 2 major criteria or 1 major and 2 minor criteria.
• Chorea may occur as the only manifestation.
• There is no single test, so diagnosis relies on medical history, physical exam, and tests.
• Throat cultures for GABHS infections are typically negative by the time RF symptoms appear, but attempts to isolate the organism should be made before starting antibiotics.
• A rapid antigen detection test allows rapid detection of group A streptococci (GAS) antigen.
• Antistreptococcal antibodies peak when rheumatic fever symptoms begin.
• The tests are useful for confirming previous GAS infection and are particularly useful in patients with chorea as the only diagnostic criterion.
• Acute-phase reactants such as C-reactive protein and erythrocyte sedimentation rate are elevated with RF, showing high sensitivity but low specificity.
• Heart reactive antibodies: Tropomyosin is elevated in persons with acute rheumatic fever.
• Chest radiography may show cardiomegaly, pulmonary congestion, or heart failure.
• Echocardiography identifies and quantifies valve insufficiency and ventricular dysfunction in acute RHD.

Medical Management

• Therapy aims to eliminate GABHS pharyngitis, suppress inflammation from the autoimmune response, and provide supportive treatment for congestive heart failure (CHF).
• Anti-inflammatory medications such as salicylates and steroids are used.
• Aspirin effectively reduces manifestations except chorea, with a dramatic response.
• Corticosteroids such as PO prednisone are added to salicylate therapy for moderate to severe carditis.
• Heart failure therapy traditionally includes an inotropic agent (Digitalis), diuretics (furosemide, spironolactone), and afterload reduction (captopril).
• Anticonvulsant medications such as valproic acid (Depakene) or carbamazepine (Carbatrol, Tegretol) are prescribed for severe involuntary movements caused by Sydenham chorea.
• Antibiotics such as penicillin are prescribed to eliminate remaining strep bacteria.
• Surgical intervention is used to decrease valve insufficiency when heart failure persists or worsens.
• About 40% of patients with acute rheumatic fever develop mitral stenosis as adults.
• A nutritious diet without restrictions is advised except for patients with CHF, who should follow a fluid-restricted and sodium-restricted diet.
• Potassium supplementation is used due to the mineralocorticoid effect of corticosteroid and diuretics.
• Patients are initially placed on bed rest, followed by indoor activity before returning to school.
• Full activity is restricted until APRs return to normal, and patients with chorea may require a wheelchair and homebound instruction.

Complications

• Rheumatic heart disease
• Endocarditis
• Valve stenosis is a narrowing of the valve.
• Valve regurgitation is a leak in the valve that causes blood to flow in the wrong direction.
• Heart muscle damage is when Inflammation weakens the heart muscle.
• Atrial fibrillation is an irregular heartbeat in the upper chambers
• Heart failure is when the heart can no longer pump blood to all parts of the body.

Prevention

• Prevention involves controlling upper respiratory tract infections.
• Administration of continuous antibiotic prophylaxis prevents recurrences.

Nursing Management

• Nursing care planning goals include reducing pain, conserving energy, promoting activity tolerance, and education about the disease, treatment, and prevention strategies.

Nursing Assessment

• Obtain a complete history from the child and caregiver, including recent sore throat and treatment history.
• Perform a physical exam to observe for major and minor manifestations and elevated temperature, pulse, or signs of chorea.
• Nursing diagnoses and interventions include:
  • Acute Pain related to inflammation and arthralgia, evidenced by verbal pain descriptions, guarding, warmth, edema, and redness.
  • Hyperthermia related to illness or inflammatory disease, evidenced by increased body temperature, hot skin, chills, tachycardia, and tachypnea.
  • Activity Intolerance related to decreased cardiac output and muscle weakness, evidenced by prolonged bed rest and limited activity.
  • Risk for Infection related to chronic disease recurrence
• Interventions for Acute Pain:
• Assess the child's pain perception using a suitable scale every 2-3 hours.
• Monitor for changes in behaviour; irritability or restlessness.
• Examine affected joints.
• Administer salicylates (as prescribed).
• Maintain bed rest during acute pain.
• Teach a child to have more self-control and pain management.
• Interventions for Hyperthermia:
• Assess temperature, heart rate, blood pressure
• Provide a patient with regular antibiotic treatment.
• Provide a tepid sponge bath.
• Teach family members the signs and symtpoms of hyperthermia.
• Interventions for Prevent injury;
• Side rails up.
• Evaluation and Goals:
• Reduced pain.
• Conserving energy.
• Preventing injury;