Rheumatic fever: Pathology and its signs and symptoms

 Rheumatic fever: Pathology and its signs and symptoms


It is also called as  acute rheumatic fever(ARF).It is an inflammatory, non supperative,immune-mediated disease developing after pharyngeal or throat infection with Streptococci (group A) (GAS). It develops after 2 to 4 weeks after the infection affecting heart, joints, central nervous system, skin and subcutaneous tissues, which sign and symptoms of fever, arthritis, carditis, chorea, subcutaneous nodules and erythema marginatum.

Repeated attacks of rheumatic fever damages heart and its valves causing rheumatic heart disease.

A quote by William Boyed- "Rheumatism licks the joint but bites the whole heart".

 Causative organism-Group A Streptococci, Streptococcus Pyogenes.  

Risk factors-

1. Genetic 

2. Malnutrition and poverty 

3. Age group 5 to 14 years

Pathology :

 It is believed to be e due to production of antibodies acting against patients own tissue. Cell mediated immunity (CMI) is raised during episodes of acute rheumatic fever. CD4/CD8 cell ratio is abnormal, there is increase in in number of natural killer cells, increase in complement components (C3 and C4). Aschoff nodules are seen in heart of patient with acute rheumatic fever. These mediators are responsible for causing pancarditis in acute rheumatic fever and ultimately vulvular lesions of Rheumatic Heart disease. Aschoff bodies are seen only in myocardium. Endocardium shows a thickened patch cell as "Maccallum's patch". A Fibrinous pericarditis is seen in many cases.

Signs and Symptoms :



T. Dyckett Jones(1944), has formulated criteria for the diagnosis of Acute Rheumatic fever which is periodically revised by the American heart Association.

According to revised Jones criteria 1992 the diagnosis is made when two of the major criteria for one major and two minor criteria are present.

# Major manifestations

1. Carditis

2.  polyarthritis

3.  subcutaneous nodules

4. Erythema marginatum

5.  Chorea

# Minor manifestations

1. Fever

2. Arthralgia 

3. Raised ESR

4. Increased C-reactive protein 

5. Increased P-R interval in ECG

 Other supportive features are-

Throat culture test positive for Streptococci, Rapid streptococcal antigen test and raised streptococcal antibody titer

Major criteria-

1.Carditis- carditis usually involves all the three layers of heart i.e. pancarditis and is associated with murmurs of vulvulitis. Carditis in later stage may develop into Rheumatic Heart disease in Acute Rheumatic fever. Symptoms are breathlessness, palpitation, chest pain, cardiac enlargement and Cardiac murmur.

2. Polyarthritis- it is the most common manifestation. It is usually a symmetrical involving large joints. Tenosynovitis is usually there. Joints are usually red, swollen, tender and painful.

3.  Subcutaneous nodules- these are firm,  painless, movable and about 0.5-2cm. These are collection of college fibers on bones or tendons, and they are seen on the extensor surface of wrist, elbow and knees. The skin above it is an inflamed and the last for 3 to 4 weeks.

4. Erythema Marginatum- Manifestation of reddish rash mainly on trunk and proximal extremities, except face. There are macular non-pruritic with pale centers and rounded margins.

5. Chorea (Sydenham's chorea) - It is a delayed neurological manifestation i.e. at least three months after the onset of disease. A characteristic series of involuntary rapid movement of all muscles is seen, face and extremities (arm)  are more severely affected. Chorea is exacerbated when patient is awake and is in stressful condition.

#Minor Criteria 

1. Fever- it is a main feature of acute rheumatic fever. Temperature ranges from 100.8 to 102°F. 

2. Arthralgia- joints pain without swelling is present.

#  Laboratory findings-

1. ESR, C- reactive protein and WBC are increased.

2. ECG shows evidence of heart block and heart failure like prolonged PR interval mitral regurgitation and pericardial effusion.

3. ASO  titer is increased.

4. Throat swab- positive throat culture for group A Streptococci. 

5. Chest X-ray shows cardiomegaly pulmonary congestion.

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