Acute Rheumatic Fever

What is the underlying pathophysiology of acute rheumatic fever (ARF)?

ARF is an autoimmune inflammatory response triggered by Group A Streptococcus (GAS) pharyngitis. Molecular mimicry causes cross-reactivity between GAS antigens (M protein) and human tissues, especially cardiac myosin, joints, skin, and brain. This leads to T-cell and antibody-mediated inflammation, resulting in pancarditis, migratory polyarthritis, chorea, subcutaneous nodules, and erythema marginatum

How does molecular mimicry contribute to cardiac damage in ARF?

The M protein of GAS resembles cardiac myosin and laminin. The immune system generates antibodies and T-cells that cross-react with these heart tissues, particularly affecting the endocardium and valves (usually mitral). This causes inflammation, fibrinoid necrosis, and scarring—leading to long-term valvular deformity (rheumatic heart disease

Why is arthritis in ARF migratory and asymmetrical?

The immune-mediated inflammation affects synovial membranes of large joints (e.g., knees, ankles, wrists), moving from one joint to another. Each joint is affected temporarily but severely, showing redness, swelling, heat, and pain before resolving and appearing in another.

What explains the elevated CRP and neutrophils in ARF?

These are markers of systemic inflammation. CRP rises in response to IL-6 and other cytokines. Neutrophilia occurs as part of the acute-phase response to tissue injury and inflammation driven by immune system overactivation following GAS infection

What is the significance of a systolic murmur in ARF?

A systolic murmur usually indicates mitral or aortic valve involvement (valvulitis), often from regurgitation due to inflammation-induced valvular dysfunction. It’s a hallmark of rheumatic carditis and may progress to rheumatic heart disease.

How does Mele’s fever relate to the pathophysiology of ARF?

Fever results from pyrogenic cytokines (like IL-1, IL-6, TNF-α) released during systemic inflammation triggered by immune cross-reactivity with host tissues. It's a common minor manifestation of ARF

What are the Jones criteria and how does Mele meet them?

• Major criteria: Migratory polyarthritis (wrist, ankle), carditis (tachycardia + murmur).

• Minor criteria: Fever, elevated CRP, tachycardia.
  Supporting evidence: Prior streptococcal infection likely (recurrent URIs, suggestive history).

What does Mele’s anaemia (Hb 97 g/L) indicate in this context?

Anaemia of chronic disease is common in ARF due to inflammation-mediated suppression of erythropoiesis and reduced iron availability. It's also possible that poor appetite, weight loss, and inflammation contributed to lower haemoglobin

Why is Mele tachycardic with a HR of 160 bpm?

Tachycardia can result from fever, anaemia (compensatory), inflammation, and early cardiac involvement (rheumatic carditis), indicating stress on the cardiovascular system and potential decreased cardiac output

Why are Māori and Pacific children at higher risk for ARF in NZ?

Due to health inequities: overcrowded housing, limited access to primary care, delayed treatment of GAS infections, systemic racism in healthcare, and reduced health literacy. These create conditions for recurrent strep infections and poor follow-up

How does Mele’s age (6 years old) impact disease presentation and risks?

Young children have developing immune systems and are more vulnerable to autoimmune complications post-infection. Symptoms like joint pain and inability to walk may delay diagnosis. Carditis risk is also higher in younger children, increasing the risk of long-term complications.

What socio-political structures influence ARF outcomes in Aotearoa?

Structures include access to culturally safe healthcare, systemic inequities in housing and income, funding for primary care services, and implementation of school-based sore throat programs in high-risk communities. Te Tiriti o Waitangi obligations also shape equitable care delivery

What are the priority nursing interventions for Mele?

• Cardiac monitoring for early detection of carditis/arrhythmia.

• Pain management for arthritis (paracetamol/NSAIDs if ordered).

• Monitor temperature and administer antipyretics as prescribed.

• Emotional support and whānau engagement.

• Educate on ARF, secondary prophylaxis, and long-term follow-up.

• Advocate for cultural liaison/support services

What models of care are important in managing Mele’s hospital experience?

• Whānau Ora: Wraparound support for whānau wellbeing.

• Te Whare Tapa Whā: Holistic Māori health model (taha tinana, wairua, whānau, hinengaro).

• Family-centred care: Involving parents in planning and education.

• Health literacy support: Clear explanations about the disease, treatment, and prevention

What is the role of secondary prophylaxis in ARF and when should it be started?

Secondary prophylaxis (e.g., benzathine penicillin IM every 3–4 weeks) prevents recurrence of ARF and worsening of heart disease. It should start as soon as diagnosis is confirmed and continue for years (duration depends on heart involvement and guidelines)

What is Acute Rheumatic Fever (ARF)

ARF is an autoimmune inflammatory disease that occurs as a delayed complication of untreated or inadequately treated Group A Streptococcus (GAS) pharyngitis.

What triggers the onset of ARF

The body’s immune system cross-reacts with host tissues due to molecular mimicry, causing inflammation in the heart, joints, skin, and brain

Describe the pathophysiology of ARF from initial infection to systemic effects

1. GAS infection triggers an immune response

2. antibodies and T cells cross-react with host proteins in the heart and joints.

3. This leads to inflammation, formation of granulomas called Aschoff bodies in cardiac tissue, valvulitis in heart valves (especially mitral), synovitis in joints, and systemic inflammation

4. causing fever and malaise

What are Aschoff bodies, and what is their significance in ARF?

Aschoff bodies are granulomatous inflammatory lesions found in the myocardium of patients with ARF. They contain T lymphocytes, plasma cells, and activated macrophages (Anitschkow cells). They indicate active rheumatic carditis and contribute to myocardial and valvular damage

How does ARF cause mitral valve regurgitation (MR) and what pathophysiological changes occur in the valve?

Immune-mediated inflammation causes swelling, fibrinoid necrosis, and fibrosis of the mitral valve leaflets, impairing their closure during systole. This leads to backflow of blood into the left atrium, increasing atrial volume and pressure, and causing a systolic murmur and eventual cardiac workload increase.

Explain the clinical signs Mele exhibits that are indicative of rheumatic carditis and MR

Mele has tachycardia, a systolic murmur, and tachypnoea. These result from increased heart rate compensating for decreased cardiac efficiency, the murmur indicating mitral valve incompetence, and tachypnoea as a sign of pulmonary congestion from left atrial overload.

What is migratory polyarthritis, and how does it develop in ARF?

Migratory polyarthritis is an inflammatory arthritis affecting large joints sequentially, caused by immune complex deposition in synovial membranes. Inflammatory cytokines cause joint swelling, warmth, pain, and reduced mobility, but it usually resolves without permanent damage

How do the joint symptoms in ARF affect Mele’s daily functioning?

Mele’s swollen, warm, and tender wrist and ankle cause pain and impaired mobility, resulting in difficulty walking and missing school, impacting her social and developmental activities.

Describe the systemic inflammatory response in ARF and its effect on laboratory markers such as CRP and blood counts

ARF triggers systemic inflammation, elevating acute phase reactants like CRP and causing leukocytosis (increased neutrophils). Inflammation also leads to anemia of chronic disease by cytokine-induced hepcidin production, lowering hemoglobin as seen in Mele’s lab results

Why is anemia common in ARF, and how does it contribute to Mele’s symptoms?

Inflammatory cytokines increase hepcidin, reducing iron availability and impairing red blood cell production. Anemia causes fatigue, weakness, and poor exercise tolerance, which worsens Mele’s ability to participate in normal childhood activities.

What are the key cardiovascular complications of ARF, and how do they progress if untreated?

Key complications include rheumatic carditis and valvular damage causing MR, possibly progressing to chronic rheumatic heart disease, heart failure, arrhythmias, and increased morbidity and mortality

How does Mele’s age impact the presentation and management of ARF?

Children are more susceptible to ARF following streptococcal infections. Growth and development can be impacted by recurrent ARF or chronic heart damage. Management includes careful dosing of medications, attention to school attendance, and support for physical activity limitations

What nursing interventions are vital for managing Mele’s ARF symptoms? Provide rationales.

• Monitor vital signs closely to detect worsening carditis (tachycardia, respiratory distress).

• Administer anti-inflammatory drugs (e.g., aspirin) to reduce joint inflammation and fever.

• Provide rest and assist with mobility to reduce joint pain and prevent fatigue.

• Educate family on importance of adherence to prophylactic antibiotics to prevent recurrence.

• Monitor nutritional status to support anemia recovery.

• Provide emotional support for missed school and activity restrictions

How do socio-cultural and socio-political factors potentially affect Mele’s care and outcomes?

Limited access to primary care delayed diagnosis. Family understanding of disease and adherence to long-term prophylaxis is critical. Socio-economic status may impact ability to attend follow-ups, afford medications, or maintain healthy nutrition. Cultural beliefs may influence acceptance of treatment

What are the clinical guidelines for managing ARF, and why is secondary prophylaxis important?

Guidelines recommend treating acute symptoms with anti-inflammatories and antibiotics to eradicate GAS. Secondary prophylaxis with regular penicillin injections prevents recurrence, reducing risk of worsening cardiac damage. Long-term follow-up is essential to monitor valve function

What developmental challenges might Mele face if ARF causes chronic rheumatic heart disease?

She may experience reduced exercise capacity, frequent hospitalizations, social isolation, and missed school. Cardiac surgery may be needed, impacting physical and psychological development

How should the nurse assess for early signs of worsening cardiac involvement in Mele?

Monitor for increasing tachycardia disproportionate to fever, new or louder murmurs, signs of heart failure (dyspnoea, edema, hepatomegaly), cyanosis, or decreased oxygen saturation

Explain why patient and family education is critical in Mele’s ongoing care

Understanding ARF’s cause and consequences improves adherence to treatment and prophylaxis, reducing recurrence. Education about symptoms of worsening disease ensures timely medical attention.

How does the pathophysiology of ARF explain Mele’s tachypnoea despite clear lung sounds?

Tachypnoea results from pulmonary congestion secondary to mitral valve regurgitation and left atrial pressure increase, leading to increased respiratory effort without infection or direct lung involvement

Why is regular monitoring of Mele’s hemoglobin and inflammatory markers necessary

To assess resolution of systemic inflammation and recovery from anemia, which reflect response to treatment and disease activity

What ethical considerations arise in Mele’s case concerning delayed diagnosis and access to care?

Ensuring equitable access to timely diagnosis and treatment is vital. Advocacy for appropriate healthcare resources and support is ethically important to prevent disease progression and complications.

What causes Acute Rheumatic Fever?

Autoimmune reaction after untreated Group A strep throat infection

What organs are mainly affected in ARF?

Heart (especially valves), joints, skin, and brain.

What is mitral valve regurgitation in ARF?

Leakage of blood back into the left atrium due to valve inflammation and damage

How does MR cause symptoms in ARF?

Causes heart murmur, tachycardia, and shortness of breath from inefficient heart function.

What is migratory polyarthritis?

Painful, swollen joints that move from one joint to another.

Why is fever present in ARF?

Due to systemic inflammation from immune response.

What lab markers indicate ARF inflammation?

High CRP, raised neutrophils, and anemia

How does ARF affect Mele’s daily life?

Causes joint pain limiting movement, school absence, and fatigue from anemia

Why is secondary prophylaxis important?

To prevent repeat infections and worsening heart damage

How does Mele’s age affect ARF management?

Children need careful dosing and support for growth and development

What nursing care is crucial for Mele?

Monitor vitals, manage pain, promote rest, support family education, and prevent complications.

How do socio-economic factors impact Mele’s care?

Affect access to healthcare, medication adherence, and follow-up.

What signs suggest worsening heart involvement?

Increased heart rate, new murmurs, breathing difficulty, and low oxygen levels.

What long-term issues can ARF cause?

Chronic heart valve disease, heart failure, and developmental delays

How does ARF cause anemia?

Inflammation reduces iron availability and red blood cell production

What triggers the autoimmune response in ARF?

Antibodies formed against Group A Streptococcus cross-react with human tissues (molecular mimicry), especially heart, joints, skin, and brain

How does the inflammatory process damage the mitral valve?

Inflammation causes swelling and scarring of valve leaflets and chordae tendineae, leading to thickening, deformity, and valve incompetence.

What is the pathophysiological basis for migratory arthritis in ARF?

Immune complexes deposit in synovial membranes causing transient inflammation that shifts from joint to joint.

Why might Mele have a systolic murmur on auscultation?

Due to mitral regurgitation caused by valve leaflet inflammation preventing full closure during systole.

How does ARF affect the heart conduction system?

Myocarditis can inflame the conduction pathways, potentially causing arrhythmias and tachycardia.

What causes the elevated C-reactive protein (CRP) in Mele’s blood tests?

CRP is produced by the liver in response to systemic inflammation during ARF.

How does anemia occur in ARF patients like Mele

Chronic inflammation suppresses erythropoiesis and iron metabolism, leading to anemia of chronic disease

What role does echocardiography play in diagnosing ARF complications?

It detects valve thickening, regurgitation, and cardiac function to confirm rheumatic heart disease

What is the significance of the elevated platelet count (thrombocytosis) in ARF?

It reflects inflammation and may increase the risk of clotting complications

Why is it important to manage fever and inflammation in ARF?

Reducing inflammation helps limit tissue damage, pain, and systemic effects

How does mitral regurgitation affect cardiac output?

Blood leaks backward into the left atrium, reducing forward flow and causing volume overload in the heart

What psychosocial impacts might Mele experience due to ARF?

School absence, limited activity, anxiety about illness, and family stress over care.

How does ARF impact respiratory function?

Heart valve dysfunction can lead to pulmonary congestion, causing tachypnea and reduced oxygen saturation

Why does Mele have a high heart rate (tachycardia)?

To compensate for reduced cardiac efficiency and anemia, increasing cardiac output.

How does the immune response in ARF affect the skin and nervous system?

It can cause subcutaneous nodules and Sydenham’s chorea (involuntary movements), though these may not appear in every case.

What is the rationale for using long-term antibiotics in ARF?

To prevent recurrent streptococcal infections that worsen autoimmune damage.

How does socio-economic status influence Mele’s access to secondary prophylaxis?

Limited resources or healthcare access can reduce adherence to penicillin injections, increasing relapse risk

What are the legal and ethical considerations in managing ARF in children like Mele?

Ensuring informed consent, protecting the child’s best interests, and addressing cultural values in care decisions.

What nursing interventions help manage joint pain in ARF?

Rest, analgesics (like NSAIDs), elevation, and gentle range-of-motion exercises once inflammation decreases.

How will Mele’s growth and development potentially be affected by repeated ARF episodes?

Chronic heart damage can limit exercise tolerance, leading to delayed physical development and school performance

What is mitral valve regurgitation

Leakage of blood back into the left atrium during systole

How does mitral valve regurgitation occur/relate to ARF

occurs due to valve damage from ARF inflammation

What is migratory arthritis in ARF?

Joint inflammation that moves from one joint to another over days or weeks

How will mitral valve damage affect Mele’s heart function?

It causes inefficient blood flow, increasing workload on the heart and risk of heart failure.

Why does Mele experience fever in ARF?

Due to systemic inflammation caused by the autoimmune response

How will the joint symptoms impact Mele’s daily activities?

Pain and swelling can limit movement, cause difficulty walking, and lead to school absence

What is the significance of elevated CRP in Mele’s bloodwork?

It indicates active inflammation in the body.

How will anemia affect Mele’s recovery and energy levels?

It reduces oxygen delivery, causing fatigue and slower healing

Why is secondary antibiotic prophylaxis critical for Mele?

To prevent repeat strep infections and further autoimmune heart damage.

What is Sydenham’s chorea and how is it related to ARF?

A neurological movement disorder caused by immune attack on the brain, sometimes seen in ARF

How will socio-economic factors influence Mele’s care adherence?

Access to healthcare and family support can affect medication adherence and follow-up

What nursing interventions can reduce Mele’s joint inflammation?

Rest, anti-inflammatory meds, joint elevation, and monitoring for complications.

How will mitral regurgitation affect Mele’s lung function?

Can cause pulmonary congestion leading to breathlessness and increased respiratory rate.

What legal considerations apply when treating a child like Mele?

Consent, confidentiality, and ensuring care aligns with child’s best interest and family values

How will repeated ARF episodes impact Mele’s long-term health?

Increased risk of chronic rheumatic heart disease and potential growth/development delays.

What role does molecular mimicry play in ARF?

It causes the immune system to mistakenly attack body tissues similar to strep antigens.

How will Mele’s anemia and tachycardia interact?

Tachycardia compensates for low oxygen delivery caused by anemia.

What is the importance of early diagnosis and treatment in ARF?

Prevents progression to severe heart damage and chronic complications.

How will Mele’s illness affect her family dynamics?

May increase stress, caregiving demands, and affect siblings and parents emotionally

What education should be provided to Mele’s family?

Importance of medication adherence, recognizing symptoms, and regular follow-up care.

What are the major crietria for the Jones Criteria

• joint involcement (arthritis)

• Myocarditis

• Nodules, subcutaneous

• Erthema marginatum

• Syenham chorea

What are the minior criterea in the Jones Criteria

• CRP increase

• arthralgia

• fever

• Elevated ESR

• prolonged PR intervals

• Anamnesis of rheumatism

• leukocytosis

What are the diagnostic criteria in the jones criteria

throat cultures or elevated antistreptolysin O titers + 2 major criteria OR 1 major and 2 minor criteria

How does the inflammatory process in ARF lead to pancarditis?

The autoimmune response causes inflammation in all layers of the heart—endocardium, myocardium, and pericardium—resulting in pancarditis, which manifests as valvulitis, myocarditis, and pericarditis.

What mechanisms lead to subcutaneous nodules in ARF?

These are painless, firm lumps formed due to granulomatous inflammation around small blood vessels in the skin and connective tissue, reflecting systemic immune activation

How does ARF cause prolonged PR interval on ECG?

Inflammation of the myocardium and conduction system delays electrical impulses through the atrioventricular node, prolonging the PR interval.

What are the key differences between acute rheumatic fever and rheumatic heart disease

ARF is the initial autoimmune inflammatory illness following streptococcal infection; rheumatic heart disease is the chronic valve damage that results from repeated ARF episodes and progressive scarring

How can ARF lead to congestive heart failure in children like Mele?

Valve damage causes volume overload and inefficient cardiac output, which strains the heart muscle, leading to heart failure symptoms such as tachypnea, fatigue, and edema

What is the importance of echocardiographic screening in children with suspected ARF?

Echocardiography detects subclinical valvular damage early, guiding timely intervention to prevent progression to severe rheumatic heart disease.