The rheumatic fever is a secondary, systemic, inflammatory disease type to an autoimmune response to streptococcal infection produced at the level of upper airway.
Cause of rheumatic fever
The causative agent of rheumatic fever is group A beta hemolytic streptococcus.
After pharyngeal infection, components of the bacteria are released that can generate antigenic determinants (epitopes) in other human tissues, which is why an autoimmune process can develop with multi-organ involvement (heart, nervous system and joints).
Symptoms of rheumatic fever
The symptoms of rheumatic fever appear after a latency period (from infection to symptoms), approximately 2 to 3 weeks. Among the general symptoms that may occur are:
- Fever: it can be high or moderate greater than 38.5 degrees Celsius, lasting several days (between 10 to 15).
- Tiredness, physical and mental fatigue.
- Arthritis (inflammation in joints) : it is one of the most frequent symptoms, affecting 75% of patients. It is characterized by being polyarticular, with an acute and insidious onset, asymmetric with migration of the affected joints and has a predilection for the lower limbs and large joints, before manifesting in the upper limbs. It can remit without sequelae.
- Arthralgia (joint pain) : equally frequent and occurs in several joints at the same time.
- Adynamia (muscle weakness) : it is characterized by the patient in whom weakness and fatigue reaches such a point that he is prostrate or it is difficult to react with movements.
- Hypo or anorexia (loss of appetite and food intake).
- Myocarditis, pericarditis or endocarditis : inflammation of the different areas of the heart, both its outer envelope (pericarditis), as well as the myocardial muscle (myocarditis) and the inner heart (endocarditis), so the patient may manifest symptoms associated with heart failure and physical examination present heart murmurs (on auscultation) due to valve alterations such as mitral regurgitation and aortic regurgitation. It has a latency period of approximately 3 weeks, you can also see alterations expressed in the electrocardiogram.
- Syndenham’s chorea (also known as San Vito’s disease or Rheumatic Korea) is an infectious disease of the central nervous system secondary to rheumatic fever in only 2% of cases, which can present months after the initial history of pharyngotonsillitis, and consists of uncontrollable and spasmodic contractions of various muscle groups, ineffective (clumsy) and similar to fasciculations, which make movements like uncontrolled dance (hence the name of Korea and Syndenham in honor of the English doctor who described the disease). You can also observe grimaces, character changes, irritability and sudden changes in mood (going from crying to laughing or vice versa).
- Subcutaneous nodules : they are small, mobile painless masses (less than 2cm), not attached to deep planes, that appear on the extension surface of the joints.
- Marginal erythema : infrequent in 5% of cases, it occurs on the arms or trunk, but does not usually give symptoms on the face. It consists of an evanescent, pinkish rash, not itchy (not itchy), with irregular edges and healthy-looking skin in the center.
- Abdominal pain that could resemble other entities such as appendicitis.
Rheumatic Fever Diagnosis
Currently there is no clinical or laboratory test to confirm the presence of rheumatic fever .
The diagnosis is based on clinical suspicion and the criteria (major and minor) of the World Health Organization, in the context of a previous infection with a group A beta-hemolytic streptococcus.
The usual clinical picture is preceded, in approximately 3 weeks, by pharyngotonsillitis, with tonsillar redness, with presence of exudate or not, petechiae (red dots) on the palate, swollen lymph nodes at the submaxillary or laterocervical level, pain when swallowing, fever and abdominal pain, subsequently appearing the previously described symptoms of the disease.
Risks of Rheumatic Fever symptoms.
The rheumatic fever may have an intensity and different evolution from patient to patient, ranging from joint pure forms more complex and severe presentations with isolated chorea or carditis or associations of various symptoms.
The severity of rheumatic fever is determined by the cardiac sequelae that could occur if cardiac and valvular integrity, as well as at the neurological level, after the presentation of symptoms compatible with Syndenham chorea.