There mononucleosis it's an illness infectious, contagious, generally acute and short-lived, of viral etiology, characterized by fever, swelling of the lymph nodes (lymphadenopathy), enlargement of the spleen (splenomegaly), increase in white blood cells in a circle (leukocytosis) and the presence in the circulation of atypical mononuclear cells.
There infectious mononucleosis is caused by the Epstein Barr Virus (EBV), with an incubation time ranging from 30-60 days for adults to 10-15 days for children. It is also called kissing disease, as one of the most frequent modes of transmission occurs with the passage of saliva infected by the virus ofEpstein Barr between two people during a kiss.
Mononucleosis: signs and symptoms
Often the onset of symptoms of mononucleosis it is sudden, with fever, usually high, headache (headache) and malaise. In the presence of these symptoms, you must immediately contact your doctor, also to avoid the improper use of antibiotics, which can also be harmful, especially with regard to pennicillins.
Here are the main manifestations in the course of mononucleosis: symptoms from the most frequent to the rarest are reported:
- Lymphadenopathy: swollen lymph nodes especially in the head and neck. The most common sign of the disease is lymphonoid swelling, especially at the laterocervical level, but real systemic lymphadenitis (inflammation of the lymphatic glands) can also appear, with the participation of the axillary, inguinal and upper limb lymphoglands. The lymph nodes are very variable in size, ranging from a pea (0.5 cm) to a walnut (2-3 cm), of hard-elastic consistency, mobile on the superficial and deep planes, and quite painful on palpation. The overlying skin is intact and does not usually appear red.
- Pharyngitis: inflammation of the pharynx. THEn more than 70% of cases during mononucleosis symptoms of a pharyngotonsillitis appear, of very variable appearance and severity, ranging from a simple erythematous pharyngitis (with redness of the mucous membrane of the pharynx) up to mimic, in severe cases, a pseudomembranous angina similar to diphtheria, manifested by sore throat and odynophagia (pain in swallowing).
In the oral cavity, small red spots called petechiae may also appear, located between the hard and soft palates. This finding, which can be observed in about one third of people with mononucleosis, appears particularly accentuated towards the end of the 1st week of illness.
Temperature: often exceeds 38 ° C, it is generally not accompanied by shivering.
- Leukocytosis: increase in the number of circulating lymphocytes. Not infrequently, monocytes with structural and functional anomalies are also observed under the microscope.
- Splenomegaly: enlargement of the spleen. In about 50% of mononucleosis cases a splenomegaly can be found: the spleen has a soft consistency and is generally only slightly enlarged; often there is also pain in the spleen, during palpation but also at rest. Care must be taken because the spleen in the course of mononucleosis is particularly fragile and increases the possibility of rupture following a possible abdominal trauma.
- Hepatomegaly: liver enlargement. Hepatomegaly is a very frequent symptom. A transient increase in liver function indices such as transaminases (AST and ALT) and cholestasis indices (GGT, ALP) usually occurs. Rarely, there have been cases of fulminant hepatitis, especially, but not exclusively, in people with congenital or acquired immunodeficiency.
- Exantenma cutaneous: skin rash with the appearance of diffuse macules and papules, which is observed in about a tenth of cases. Diffuse maculopapular rash may resemble that of rubella, but, less frequently, it may also be morbilliform, scarlet fever or urticarial. The rash is particularly frequent and pronounced in subjects treated with penicillins.
- Jaundice: rare symptom (9% of cases), indicates a transient increase in circulating bilirubin.
- Thrombocytopenia: reduction of circulating platelets. Moderate thrombocytopenia is very common; only rarely is there a marked decrease in platelets (probably induced on an autoimmune basis) with an increased risk of bleeding (haemorrhagic diathesis).
- Loss of appetite and weight loss: often in the course of mononucleosis there is hyporexia (loss of appetite) and consequent loss of body weight. It is good to hydrate yourself a lot and integrate mineral salts and vitamins appropriately in case the lack of appetite lasts for several days.
In addition to these signs and symptoms which represent the most common findings of the disease, sometimes other manifestations are detected, expression of rare localizations of the virus.
- Neurological symptoms: Neurological syndromes have been described in fewer than 1% of cases: they include clear liquor meningitis, encephalitis with or without cerebellar involvement, and Guillain-Barré syndrome.
- Inflammation of other systems / organs: cases of inflammation of the pericardium, the membrane that surrounds the heart (pericarditis), inflammation of the heart (myocarditis) and inflammation of the testicles (orchitis).
- Anemia: reduction of red blood cells and / or circulating hemoglobin: in 0.5-3% of cases, autoimmune haemolytic anemia due to cold agglutinins (especially IgM type), which are also present in 70-80% of patients, in the most cases without giving associated symptoms. As a rule, hyperhemolysis is clinically revealed in the second and third weeks of the illness, then regressing within a couple of months.
Duration of symptoms of mononucleosis
Those described above are the initial symptoms, which arise in the first days of the illness: typically the fever and the involvement of the oral cavity persist 1-2 weeks; lymph nodes, on the other hand, appear to have increased in volume for a usually longer time (2-3 weeks). In some cases the spleen is still enlarged and palpable several weeks after the onset of mononucleosis. In children, the disease has a shorter course, with usually low fever.
Infectious mononucleosis is a disease with a decidedly favorable outcome. Only on very rare occasions, especially in people with immunodeficiency, can mononucleosis put the patient at risk of life, in the event of the proliferation and dissemination of EBV at a systemic level, for splenic rupture, for neurological complications or in the case of respiratory difficulties.
In rare cases, it appears that mononucleosis can become chronic, resulting in an ipersistent EBV infection, and which secondarily may be responsible for the so-called “fatigue syndrome chronic ", characterized by marked fatigue (asthenia), muscle pain (myalgia), low-grade fever, joint pain (arthralgia), headache and depression of mood.
In favor of this theory there is the fact that in patients with chronic fatigue syndrome there are unusually high titers of anti-EBV antibodies (especially towards early antigens). However, subsequent studies have drawn attention to other possible etiologies, without, in truth, any precise conclusion.