Infectious mononucleosis - Symptoms

Infectious mononucleosis has a cyclical course. The incubation period, according to various sources, varies from 4 to 50 days.

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The main symptoms of infectious mononucleosis and the dynamics of their development

There is an initial period of the disease, a period of peak, and a period of convalescence. In most cases, infectious mononucleosis begins acutely, with an increase in body temperature, the appearance of a sore throat and enlarged lymph nodes. With a gradual onset, pain and enlarged lymph nodes precede the increase in temperature for several days, then a sore throat and fever appear. In any case, by the end of the week, the initial period of the disease ends and all the symptoms of infectious mononucleosis are revealed.

The period of the peak of the disease is characterized by:

• fever;
• polyadenopathy:
  • damage to the mouth and nasopharynx:
    • hepatosplenic syndrome;
    • hematological syndrome.

The febrile reaction is diverse both in the level and duration of fever. At the onset of the disease, the temperature is often subfebrile, at its height it can reach 38.5-40.0 C for several days, then decrease to a subfebrile level. In some cases, subfebrile temperature is noted throughout the disease, in rare cases there is no fever. The duration of fever is from 3-4 days to 3-4 weeks, sometimes longer. With prolonged fever, its monotonous course is revealed. The peculiarity of infectious mononucleosis is the weak expression and originality of the intoxication syndrome. Patients note such symptoms of infectious mononucleosis as: loss of appetite, myasthenia, fatigue, in severe cases, patients cannot stand due to myasthenia, they sit with difficulty. Intoxication lasts for several days.

Polyadenopathy is a constant symptom of infectious mononucleosis. Most often, the lateral cervical lymph nodes enlarge, they are often visible to the eye, their sizes vary from a bean to a chicken egg. In some cases, edema of the tissue around the enlarged lymph nodes appears, the contours of the neck change (the "bull neck" symptom). The skin over the lymph nodes is not changed, they are sensitive to palpation, have a dense elastic consistency, are not fused with each other and with the surrounding tissues. Other groups of nodes also enlarge: occipital, submandibular, cubital. In some cases, the inguinal-femoral group is predominantly enlarged. In this case, pain in the sacrum, lower back, severe weakness are noted, changes in the oropharynx are weakly expressed. Polyadenopathy regresses slowly and, depending on the severity of the disease, persists from 3-4 weeks to 2-3 months or becomes persistent.

The following symptoms of infectious mononucleosis are also noted: enlargement and swelling of the palatine tonsils, which sometimes close together, making it difficult to breathe through the mouth. Simultaneous enlargement of the nasopharyngeal tonsil and swelling of the mucous membrane of the inferior turbinate make nasal breathing difficult. At the same time, the face becomes puffy, the voice becomes nasal. The patient breathes with an open mouth. Asphyxia may develop. The back wall of the pharynx is also edematous, hyperemic, with hyperplasia of the lateral columns and lymphoid follicles of the back wall of the pharynx (granulomatous pharyngitis). Often, dirty gray or yellowish-white deposits in the form of islands, stripes appear on the palatine and nasopharyngeal tonsils, sometimes they completely cover the entire surface of the tonsils. The deposits are loose, easily removed with a spatula, and dissolve in water. Fibrinous plaques or superficial necrosis of tonsil tissue are rarely observed. Plaques may appear from the first days of the disease, but more often on the 3rd-7th day. In this case, the appearance of plaques is accompanied by a sore throat and a significant increase in body temperature.

Enlargement of the liver and spleen is an almost constant symptom of infectious mononucleosis, especially in children. The liver enlarges from the first days of the disease, minimally at its height. It is sensitive to palpation, dense, splenomegaly persists for up to 1 month. Moderate increase in ALT and AST activity is often detected, less often - darkening of urine, mild jaundice and hyperbilirubinemia. In these cases, nausea and loss of appetite are noted. The duration of jaundice does not exceed 3-7 days, the course of hepatitis is benign.

The spleen enlarges on the 3rd-5th day of the disease, maximally by the 2nd week of the disease and ceases to be accessible for palpation by the end of the 3rd week of the disease. It becomes slightly sensitive to palpation. In some cases, splenomegaly is sharply expressed (the edge is determined at the level of the navel). In this case, there is a threat of its rupture.

The blood picture is of decisive diagnostic importance. Moderate leukocytosis is characteristic (12-25x10 ⁹ /l). Lymphomonocytosis up to 80-90%. Neutropenia with a left shift. Plasma cells are often detected. ESR increases to 20-30 mm/h. The appearance of atypical mononuclear cells is especially characteristic from the first days of the disease or at its height. Their number varies from 10 to 50%, as a rule, they are detected within 10-20 days, i.e. they can be detected in two tests taken at an interval of 5-7 days.

Other symptoms of infectious mononucleosis: rash, usually papular. It is observed in 10% of patients, and in 80% when treated with ampicillin. Moderate tachycardia is possible.

Among the atypical forms, a latent form is described, in which some of the main symptoms are absent and serological tests are required to confirm the diagnosis.

In rare cases, a visceral form of the disease is observed with severe multi-organ damage and an unfavorable prognosis.

A chronic form of the disease is described, which develops after acute infectious mononucleosis. It is characterized by weakness, fatigue, poor sleep, headaches, myalgia, subfebrile temperature, pharyngitis, polyadenopathies, exanthema. Diagnosis is possible only with the use of convincing laboratory tests.

Classification of infectious mononucleosis

Infectious mononucleosis has typical and atypical forms, by severity - mild, moderate and severe forms of the disease. Currently, a chronic form of infectious mononucleosis has been described.

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Complications of infectious mononucleosis

Infectious mononucleosis rarely has complications, but they can be very severe. Hematological complications include autoimmune hemolytic anemia, thrombocytopenia, and granulocytopenia. Neurological complications include encephalitis, cranial nerve palsies, including Bell's palsy or prosopoplegia (paralysis of the facial muscles caused by damage to the facial nerve), meningoencephalitis, Guillain-Barré syndrome, polyneuritis, transverse myelitis, and psychosis. Cardiac complications (pericarditis, myocarditis) are possible. Interstitial pneumonia is sometimes observed in the respiratory system.

In rare cases, the spleen ruptures during the 2nd or 3rd week of the disease, accompanied by sharp, sudden abdominal pain. The only treatment method in this case is splenectomy.

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Mortality and causes of death

Causes of death in mononucleosis can include encephalitis, airway obstruction, and rupture of the spleen.