Infectious mononucleosis - Practical hematology of children's age

The infectious mononucleosis is the disease which is characterized by specific changes in peripheral blood and damage of lymphatic system. Emergence of peculiar cells in peripheral blood allows to include this pathology in the section of leukemoid tests. The disease is for the first time described by the outstanding domestic pediatrician N. F. Filatov in 1885 and a bit later, in 1889 E. Pfeiffer. An infectious mononucleosis — a disease of the virus nature. The probable etiological agent the gerpesopodobny virus of Epstein — Burra is considered, however its specificity is completely not proved. Contageousness of a disease low, assume an airborne way of infection. As a rule, isolated cases are registered though small epidemic flashes are possible. People of various age get sick with an infectious mononucleosis, however the peak of incidence is the share of age of 2 — 9 years. Children of chest age are ill seldom. At boys the disease is registered twice more often than at girls.
The clinical picture of an infectious mononucleosis is various. The most constant symptoms: hyperadenosis, quinsy, increase in a liver and spleen. The disease can proceed benign — with the insignificant catarral phenomena and recovery within 5 — 7 days. Severe forms — with the expressed clinical picture, with fever for several weeks can be observed. The incubation interval makes from 4 to 28 days, on average 1 — 2 week. The disease can gradually begin, with the prodromal phenomena: loss of appetite, headache, dizziness, mialgiya, arthralgia. The acute sudden beginning — high temperature which quite often is the first symptom of a disease is more often noted. At a number of patients temperature has subfebrile character. The temperature curve at an infectious mononucleosis has no certain pattern. Usually it the wrong type — lowering in the morning. Duration of temperature reaction depends on severity of a disease. At easy forms it disappears in 5 — 7 days, at severe forms subfebrile condition can remain for 2 — 4 weeks.
Along with temperature increase or a bit later there are catarral phenomena — the complicated nasal breath, a pharynx hyperemia, throat pain, dry cough. Such clinical picture is mistakenly regarded sometimes as an acute respiratory viral disease. The complicated nasal breath can be the first symptom of a disease, even before temperature increase; it is caused by defeat of an adenoid tissue of a nasopharynx. At the same time characteristic feature is absence separated from a nose as there is no exudative phase of an inflammation of a mucous membrane of a nose. At many patients on 3 — the 4th day of a disease joins quinsy which is an important symptom of an infectious mononucleosis. At survey of a handle and almond are edematous, loosened. At children hypostasis of a soft palate and a uvula can be noted. On almonds the gray plaque which easily is removed is visible. Quinsy on character is various — from catarral to ulcer and necrotic and ulcer diftericheskoy, the last form can have similarity to pharynx diphtheria. Defeat and a nasopharyngeal almond is possible.

The most characteristic and constant symptom of an infectious mononucleosis is an increase in peripheral lymph nodes. Lymph nodes swell up a little from the first days of an illness and reach the maximum sizes on 4 — the 5th day. Their size from 0,5 — 1 cm to 3 — 4 cm in the diameter. At a palpation lymph nodes of a dense consistence, are mobile, are not soldered among themselves and surrounding fabrics, as a rule, do not abscess. Such important sign as morbidity at a palpation attracts attention. Also localization of defeat of lymph nodes is characteristic. The cervical group, especially zadnesheyny lymph nodes located on the rear edge grudino - a clavicular and mastoidal muscle is mainly increased. Lymph nodes of front cervical area, occipital, submaxillary, sometimes axillary, inguinal are also involved in process. Less often lymph nodes of a mediastinum and an abdominal cavity are surprised. In the latter case the abdominal pain simulating an acute appendicitis is noted. The increased lymph nodes tend to fast involution within 10 — 14 days. However the small swelling and morbidity can remain a long time — for several weeks and even months.
The increase in a spleen, usually moderate belongs to frequent symptoms of an infectious mononucleosis is 2 — 3 cm lower than a costal arch. Cases of significant increase in a spleen are described. At research the palpation of body has to be carried out carefully as there are supervision of a rupture of a spleen after rough survey. The spleen has a dense consistence, generally painless. Reduction in the sizes happens very slowly and the splenomegaly can remain a long time after recovery.
At an infectious mononucleosis at many patients damage of a liver with disturbance of its functions is observed. The liver is usually increased moderately, acting on 2 — 3 cm from under edge of a costal arch, dense, at a palpation morbidity is noted. Manifest symptoms of hepatitis in the form of jaundice occur at 5 — 10% of children. At laboratory researches at most of patients easy or moderate abnormal liver functions — moderate increase of level of bilirubin, transaminases, positive sedimentary tests come to light. At histologic research of a liver of patients with an infectious mononucleosis a certain similarity with an infectious viral hepatitis, lymphomonocytic infiltratsiy hepatic fabric is found. Functions of a liver are normalized during 4 — 6 weeks. Cirrhosis belongs to rare complications.
In a clinical picture of an infectious mononucleosis at children also other, more rare symptoms, in particular skin rash are noted. Rash on character can be spotty and papular, urtikarny. Sometimes during the early periods of a disease hemorrhagic rash on skin and mucous membranes of an oral cavity develops. Hypostasis of an upper eyelid occurs at children. At an infectious mononucleosis defeat of a nervous system — from insignificant frustration (a headache, the meningism phenomena) before heavy disturbances with mental disorders, sight loss, development of paralyzes of upper and lower extremities is possible.
At an infectious mononucleosis in peripheral blood the changes having diagnostic value are observed. From the first days of a disease the leukocytosis within ^{15 X 109/l — 25 X 109/l}, in some cases — to ^35ò109/l and is noted above. However the infectious mononucleosis can proceed with normal quantity of leukocytes and even with a leukopenia. Specific changes in a leykogramma are expressed in dominance of one-nuclear cells (mononuklear) — lymphocytes and monocytes. The part of them has usual morphology. Diagnostically a valuable sign — existence of atypical mononuklear. These cells are characterized by considerable polymorphism: the sizes and forms of cells, kernels are variable. Similarity as with lymphocytes, and monocytes is morphologically noted that formed the basis to call cells lymphomonocytes. However this term is inexact as from positions of the modern theory of a hemopoiesis such cell cannot be formed in connection with various origin of lymphocytes and monocytes at the level of progenitors of the II class. Now distinguish two types of atypical mononuklear: monocytosimilar and limfotsitopodobny. The big sizes, irregular shape of a kernel, wide basphilic cytoplasm are characteristic of the first. Limfotsitopodobny atypical mononukleara have the smaller sizes, a roundish homogeneous kernel, rather wide blue rim of cytoplasm. Cytochemical researches also testify to heterogeneity of atypical mononuklear. So far the origin of atypical mononuklear is not clear. In works of the last years on the basis of immunological researches are suggested that they are modified T lymphocytes. The quantity of atypical mononuklear in smears of peripheral blood can fluctuate over a wide range. At diagnosis of an infectious mononucleosis percentage of cells is important. This results from the fact that atypical mononukleara or as they are called still, virotsita (formation of such cells has the virus nature), meet in small percent at some other viral infections. They can be observed at children at measles, chicken pox, infectious hepatitis, acute respiratory viral diseases. According to a number of authors, for statement of the diagnosis of an infectious mononucleosis 10 — 20% of virotsit there are enough.
In peripheral blood at most of patients the relative or absolute neutropenia is also noted. At a number of patients it is possible to reveal an eosinophilia. In some cases in peripheral blood the increased quantity of plasmocytes is observed, SOE is moderately increased. Anemia and thrombocytopenia are not characteristic of an infectious mononucleosis though insignificant falling of these indicators can be observed. At the same time, cases of immune hemolitic anemia and thrombocytopenia with a hemorrhagic syndrome are described.

Changes in peripheral blood are so typical at an infectious mononucleosis that need for a puncture of marrow is absent.

Studying of punctate or bioptat of a lymph node make in rare instances when the mistake in the diagnosis is possible. Therefore diagnosis can be added with serological researches. Paul's reaction — Bunnelya in Davidson's modification differs in high specificity. At this test the caption of heterophyllous antibodies which can remain raised within many months comes to light. The caption 1:40 and is diagnostic above.
The infectious mononucleosis, as a rule, proceeds is good-quality. Hematologic changes most clearly come to light on 7 — the 14th day of an illness. Then there comes reduction of quantity of lymphocytes and monocytes, however monocytic and lymphatic reaction can long time (about one year and more) to keep in peripheral blood after absolute clinical recovery. The forecast is favorable, recovery in most cases comes in 2 — 4 weeks. Cases of recurrence of a disease are noted. Complications are observed very seldom, are caused by accession of an infection. In literature there are descriptions of fatal cases at an infectious mononucleosis. The disease is not transformed to an acute leukosis, however there are messages on a combination of a leukosis and an infectious mononucleosis.
Despite rather high incidence, diagnosis of an infectious mononucleosis is difficult. The greatest difficulties are caused by differential diagnosis with an acute leukosis. A number of kliniko-hematologic symptoms at these diseases has similarity: fever, hyperadenosis, liver, spleens, leukocytosis. Additional difficulties are brought by the wrong morphological interpretation of the apitichny mononuklear taken for blast cells. However there is a number of the basic signs allowing to carry out the correct differentiation of diseases.
At an infectious mononucleosis morbidity at a palpation of lymph nodes which is absent at an acute leukosis is noted. The anemia and thrombocytopenia observed at leukoses are not typical. Crucial diagnostic importance has research of peripheral blood and if necessary — miyelogramma. The main symptom of an acute leukosis — a large number of typical blast cells, defeat of all sprouts of a hemopoiesis.
In the differential and diagnostic plan it must be kept in mind a lymphogranulomatosis. However for it morbidity of lymph nodes is not inherent, local hemilesion is characteristic. In peripheral blood the leukocytosis and a neutrocytosis are noted.
Patients are not subject to hospitalization, excepting persons with severe forms of a disease. In house conditions observance of a bed rest during the acute period of a disease is required. There is no special treatment of an infectious mononucleosis and, as a rule, it does not demand active intervention. Appoint a short course of the desensibilizing therapy, vitamin drugs. At the expressed quinsy appoint antibiotics of a penicillinic row for impact on bacterial flora, rinsing of a pharynx bactericidal solutions. At development in patients of immune hemolitic anemia, thrombocytopenia, the expressed allergic manifestations at the same time appoint glucocorticoids in small dosages (Prednisolonum — 1 mg/kg of body weight a day). A sick infectious mononucleosis also physioprocedures on the increased lymph nodes both during the acute period of a disease are strictly contraindicated thermal, and during reconvalescence. After the postponed disease at children the long time can remain an asthenic syndrome. Restriction of exercise stresses, fortifying actions is recommended: walks in the fresh air, easy gymnastics, good nutrition, vitamin therapy. Due to the damage of a liver certain restrictions have to be observed in a diet. Within a year preventive inoculations and insolation are contraindicated to the children who transferred an infectious mononucleosis.