Generality
Rheumatism in the blood identifies a disease characterized by an acute inflammation that mainly involves the joints and the heart .
Also known as rheumatic fever, rheumatism in the blood can represent the late complication of an infection by group A streptococcus, a pathogen that commonly causes inflammation of the throat (pharyngitis) and tonsils (tonsillitis).
More in detail, rheumatism in the blood is the result of a cross-reaction between the antibodies produced by the immune system against streptococcal antigens and some tissue antigens, present mainly in the skin, joint and heart.
The clinical picture that results varies according to the location, but the onset symptoms most frequently associated with their presence are joint pain (in the peculiar form of migrating polyarthritis) and fever .
If tonsillitis is not treated properly, the likelihood of contracting rheumatism in the blood is higher.
What are
Rheumatism in the blood is the result of the interaction between antibodies produced by the organism against group A streptococcal antigens and some tissue antigens, present mainly in the skin, joint and heart.
In other words, the damages that result from the complication of throat infection depend mainly on an autoimmune reaction, supported by a structural similarity between some antigens of the bacterium and those of our organism ; this phenomenon is known as antigenic mimicry .
The consequence of this anomalous activation of the immune system is a multisystemic inflammatory disease, from which arthritis, valve dysfunction and rheumatic heart disease (ie inflammation of endocardium, myocardium and pericardium) also derive.
Causes
Rheumatism in the blood is manifested as a post-infectious sequela of pharyngitis or tonsillitis from Streptococcus pyogenes (or group A beta-hemolytic streptococcus), not adequately treated.
This occurrence was quite common before the introduction of antibiotics into medical practice. Currently, in industrialized countries, the incidence is reduced: rheumatism in the blood affects 1 individual per 100, 000, without distinction between men and women.
Situation in developing countries
Rheumatism in the blood represents one of the major public health problems in many developing countries (including: Congo, Zambia, Morocco, Sudan, Ethiopia, India and some areas of Australia).
Their incidence is still quite high, reaching peaks of 100 individuals per 100, 000, mainly due to hygienic-environmental conditions . In industrialized countries, on the other hand, there has been a rapid decline in blood rheumatism since the second post-war period, thanks to the greater availability of penicillin and the general improvement in living conditions.
Rheumatism in the Blood: pathogenesis
The contribution of group A beta-hemolytic streptococcus in the development of rheumatism in the blood is known, although the pathogenesis of this complication is complex and not yet perfectly clarified.
When pharyngitis-tonsillitis does not completely heal (since it is NOT carefully treated), the immune system continues to produce antibodies. In some conditions, the latter can activate abnormally and react both against streptococcal antigens and against some of the organism's own tissue antigens.
In fact, many antigens of group A streptococci are similar to some glycoproteins found in the synovium and myosin of myocardial fibers present on the heart valves . This molecular mimicry helps to sustain, therefore, the tissue damage that characterizes rheumatism in the blood.
For further information: Group A beta-hemolytic streptococcus - pathogen characteristics »Rheumatism in the Blood: who is most at risk
Rheumatism in the blood can present at any age: streptococcal throat infection has a peak incidence between 5 and 15 years, but can also affect adults.
Environmental and constitutional factors, including a certain genetic predisposition, seem to make them more susceptible to streptococcal infections and their consequences.
A previous streptococcal infection in the 3 years preceding the appearance of rheumatism in the blood constitutes a strong risk factor and should be considered during the diagnostic procedure.
Symptoms and Complications
Rheumatism in the blood can affect many organs and tissues, therefore the clinical manifestations vary depending on the extent of the inflammation and the districts of the body involved by it.
The most frequent symptom is the polyarthritis of a migrant nature, so defined by the characteristic of passing from one joint to another: in practice, when the joint inflammation is in remission or has been resolved recently, an inflammatory process appears dependent on another joint.
Rheumatism in the blood: when do they occur?
In most cases, the onset of rheumatism in the blood is abrupt, with fever and / or acute arthritis, which follow a primary streptococcal infection in the throat, in the form of pharyngitis or tonsillitis.
Symptoms typically occur after 2-4 weeks . In some cases, however, rheumatism in the blood or their complications can begin even years after the primary infectious disease.
Early symptoms
Usually, rheumatism in the blood begins with:
- Fever ;
- Joint pain ( arthralgia) .
At the same time, subtle inflammation attacks the heart valves (especially the mitral valve that separates the atrium from the left ventricle) and, gradually, can compromise its functioning. In the long run, rheumatism in the blood can cause permanent damage, favoring the development of heart disease .
Joint inflammation and fever resolve in about 2-4 weeks (if untreated). When the infection is not completely eradicated, chronic sequelae can recur at varying time intervals, even years later.
Characteristics of joint pains
Joint pain associated with rheumatism in the blood:
- They can be mild or severe;
- They migrate from one joint to another (migrant arthritis);
- They last two to four weeks.
Over 75% of patients have articular manifestations on the first episode of the disease. Rheumatism in the blood mainly affects the large joints, such as ankles, knees, elbows and wrists, which, in addition to being painful, can be swollen, reddened and hot .
Rheumatism in the blood: other associated manifestations
At these manifestations, other specific symptoms may be added such as:
- Erythema marginato on trunk or upper limbs (rarely on the lower limbs, never on the face): the rash is made up of pink-colored macules or papules, roundish in shape. The rash is painless and is not itchy; this cutaneous manifestation of rheumatism in the blood can last from a few minutes to a few hours and is often associated with carditis.
- Subcutaneous nodules on the flexor surfaces: at the level of the joints, near bony protuberances or near tendons, nodular formations can appear, painless and transient, of a size equal to about 0.5-2 cm.
- Sydenham Korea : represents the neurological involvement of rheumatism in the blood. Korea consists of involuntary, abrupt and irregular movements that can begin in the hands, feet and face and then become generalized. The appearance occurs late, 6-8 weeks after the pharyngeal streptococcal infection, after the other manifestations have already regressed. The associated motor symptoms include weakness and muscular hypotonia. Sydenham's chorea usually lasts from a few weeks to several months and resolves completely in most patients.
Other non-specific symptoms associated with rheumatism in the blood are:
- Pains in the abdomen;
- Fatigue;
- Anorexia (lack of appetite);
- Epistaxis.
Rheumatic cardite
The most severe consequence of rheumatism in the blood consists mainly in a distorting alteration of the heart valves, which leads to their progressive dysfunction. Inflammation mainly involves the mitral valve and, to a lesser extent, the aortic valve, although the combined involvement of all four valves has been described.
Chronic rheumatic carditis is one of the main causes of mitral stenosis.
The cardiac involvement of rheumatism in the blood can manifest itself with:
- Pericardial rubs and puffs;
- Hemodynamic disorders;
- Chest pain.
The combination of carditis and valve dysfunction can result in pulmonary hypertension and / or heart failure, which is manifested by:
- Dyspnoea;
- Pain in the upper right quadrant or epigastrium;
- Drowsiness;
- Easy fatigability.
Diagnosis
The diagnosis of rheumatism in the blood is based on the application of JONES criteria and on information deriving from medical history, physical examination and laboratory analysis (microbiological and immunological).
Laboratory tests and instrumental exams
At the diagnosis of rheumatism in the blood, the results of some laboratory tests and instrumental investigations can contribute.
Streptococcus infection can be found with the microbiological analysis of a sample taken by throat swab or altered values of the antistreptolysinic titre (TAS) in the blood .
For further information: Antistreptolysinic titre - normal and pathological values »An indication of the ongoing inflammatory rheumatism process in the blood is also provided by the increase in the values of the inflammatory VES markers (erythrocyte sedimentation rate) and PCR (C reactive protein).
The electrocardiogram and the echocardiogram serve instead to highlight the presence of arrhythmias and valvulopathy.
Analysis of the clinical picture
The definition of a first episode of rheumatism in the blood requires the presence of:
- 2 symptoms belonging to the major criteria
or
- 1 major event and 2 minor events
To establish the diagnosis, symptoms must be associated with evidence of Group A Streptococcal infection (rapid antigen test, high or rising antistreptococcal antibody titer and positive pharyngeal swab).
The major diagnostic criteria of JONES require the presence of migrating polyarthritis, carditis, chorea, erythema and subcutaneous nodules; Minor criteria, on the other hand, are: fever, arthralgia, ESR or high C-reactive protein and, on the electrocardiogram, an elongation of the PR interval (index of heart block of first degree).
Treatment
In the acute phase, the therapy of rheumatism in the blood includes the administration of:
- Aspirin or other NSAIDs (non-steroidal anti-inflammatory drugs) : these drugs are indicated to suppress inflammation and control acute symptoms. The salicylates determine a rapid remission of fever, arthritis and arthralgias; medicines based on acetylsalicylic acid should not be administered, however, in children under 12 years of age.
- Corticosteroids : they rapidly reduce the inflammatory response and, if acute carditis is present, may contribute to induce their remission;
- Antibiotics : they are useful for eradicating a residual streptococcal infection and preventing recurrences; penicillin is considered the drug of choice for the eradication of a possible upper airway infection from group A beta-hemolytic streptococci. If the patient is allergic, a therapy with erythromycin and cephalosporin is recommended, depending on the timing and method indicated by your doctor.
Other measures to promote recovery from rheumatism in the blood include bed rest and the limitation of any physical activity that can further aggravate inflamed structures.
The timing for healing depends on the severity of the primary infection; prolonged episodes of rheumatism in the blood, lasting more than 8 months, occur in about 5% of patients and correlate with a worse prognosis.
Patients with severe cardiac rheumatism in their blood can suffer permanent heart damage . In some cases, such occurrence requires surgical therapy or, possibly, surgical replacement of the valves.
