Monday, February 25, 2013

All About Infectious Mononucleosis (The Epstain Barr Viral Infection)




Infectious mononucleosis is an acute infectious disease that is caused by the Epstein-Barr virus is characterized by the fever, tonsillitis, increase of lymphatic nodes, hepato- and splenomegaly, by presence of atypical mononuclear cells in a peripheral blood and heterophyl antibodies.

Etiology: an EBV, belong to Herpes viruses, type IV

Epidemiology:
Source of infection are patients with symptomatic and asymptomatic forms, EBV-carriers
Mechanism of transmission is droplet, rarer is contact. The virus is transmitted primarily through saliva during speaking, breathing, coughing, especially during kisses, hand-to-hand contacts.
The transmission of EBV through blood product transfusions has been well documented.
Susceptibility - any age, disease is low contagious, more frequent up to 15 years, in boys

Pathogenesis:
Inoculation of the virus into upper respiratory tract mucous membranes.
Diffusion by lymph to the lymph nodes, spleen, liver.
Lymphoprolipherative syndrome.

Bacterial complications.

Persistence of the virus (even 16 months or more).

 

Clinical criteria

Incubation period is 10-15 days (may be longer-2 month).
Beginning is acute from fever, intoxication (headache, myalgia, arthralgias, malaise).
Fever usually febrile from 3 days till 3 weeks
Tonsilopharyngitis, which may be exudative (follicular, lacunar) in case of secondary bacterial infection (photo), lymphoid follicles hyperplasia (on the back pharyngeal wall).
Adenoiditis, posterior rhinitis (appearance of the patient is typical – breathing with open mouth, absence of nasal discharge, usually snore is present).
Generalized lymphadenopathy with previous enlargement of cervical and occipital lymph nodes (photo).
Hepatosplenomegaly is the sign of lymphoproliferative syndrome (photo).
Maculopapular rashes (photo), wich may confluence with erythema development (photo), sometimes hemorrhagic elements with later skin pigmentation (photo) may occur as a sign of hypersensitivity in case of amoxicillin, ampicillin treatment (in 70-80%).  In the young childhood patient in 25% of cases “spontaneous” rashes can develop.
Other signs: hepatitis (jaundice form of infectious mononucleosis);
toxic myocarditis
diarrhea.

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Tonsilopharyngitis

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Tonsilopharyngitis

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Generalized lymphadenopathy with previous enlargement of cervical lymph nodes

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Generalized lymphadenopathy with previous enlargement of cervical lymph nodes

IMG_70 IMG_71
Hepatosplenomegaly

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Maculopapular rashes

IMG_75
Maculopapular rashes wich confluence

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Maculopapular rashes wich confluence

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Toxic erythema (next day)

Pigmentation in few days

Classification     
         Form:         - typical                                           
                            - atypical:   - effaced (mild)              
                                               - asymptomatic (subclinical) mild
                                               - visceral - severe (heart, kidneys, adrenal glands, CNS damage)
         Severity (for typical forms):     - mild
                                               - moderate
                                               - severe
         Duration    -    smooth (uncomplicated)
complicated
prolonged

Infectious mononucleosis Severity Criteria

Sign
Mild
Moderate
Severe 
Toxic syndrome
absentmild
Moderate 
Expressed
Body t°
Up to 38 °С
38,5-39 °С
More than 40 °С
Lymph nodes damage
mildcervical predominantly
markedcervical especiallyvisible
conglomeratesneck disfigurationneck subcutaneous tissue swelling
Nasal breathing
Some labored
Labored, "snoring" in sleep
Absent, snoring, opened mouth, puffy face
Throat damage
Catarrhal tonsillitis
tonsils hyperplasia  1st-2nd degree, considerable exudates
tonsils hyperplasia  3rd degree, large membranous exudates
Hepato-  splenomegaly(outcome from the rib arch)
Up to 2-3 сm
3-4 сm
4-5 сm and more,jaundice
Atypical mononuclear cells number
Up to 30 %
20-50 %
More than 50 %
Cough 
Rare 
Often 
Often
Rashes 
Rare 
Often
Hemorrhagic in 1/3, nasal bleeding
Dyspepsia
Rare 
Present abdominal pain, vomiting
abdominal pain, several vomiting
Heart changes “toxic-infectious heart
Not typical
Rare 
Often

Peculiarities of infectious mononucleosis in infants:
often catarrhal syndrome is present (coughsneezing, corryza);
expressed polyadeniasnoreedematous face from the first day of the disease;
early development of bacterial tonsillitis (on the third day);
rashes are more often;
dyspepsia;
in the peripheral blood – neutrophyllosis with left shift;
favorable duration.

Complications, which may occur (rare):  
Respiratory tract – pneumonia, airway obstructions.
Neurological – seizures, meningitis, encephalitis, peripheral facial nerve paralysis, Gillian – Barrette syndrome. 
Hematological – thrombocytopenia, hemolytic anemia.
Infectious – recurrent tonsilopharyngitis.
Renal – glomerulonephritis.
Genital – orchitis.
Spleen rupture (is lethal).

 

Laboratory findings

Blood analyses: leucocytosis, even 15-30,000/mm3, lymphocytosis, monocytosis, appearing of atypical mononuclear cells (virocytes) more than 10%, ESR enlarges to 20-30mm/hour.
Heterophil agglutination test (is positive in 25-95% of preschool children, 53-94 young school children, and nearly 100% of older children).
Immune-enzyme method – VCA Ig M, EA Ig M presence in the blood.
PCR (measuring of EBV nucleinic acid in the blood, saliva, lymphatic tissues).

atypical mononuclear cells

Diagnosis example:
Infectious mononucleosis, typical form, moderate severity, complicated by the bilateral  bronchopneumonia  

Differential diagnosis should be performed with ‘mononucleosis like’ syndrome caused of AIDS. Another disease, which has similar features: diphtheria, adenoviral infection, acute leukemia, lymphogranulomathosis, viral hepatitis etc.

Sign
Pseudotuberculosis
Scarlet fever
Infectious mononucleosis
Typhoid fever
Enterovirus infection
Viral hepatitis
Beginning
Acute
Acute
Acute
Acute
Acute
Acute,
subacute
Initial signs
Toxic,  dyspeptic and different other
signs
Sore throat, toxic
Lymphoproliferative, toxic
Toxic
Catarrhal, toxic
Catarrhal,dyspeptic, arthralgicasthenic
Rashes
Pin-point, maculous-papulous, erythema
Pin-point, sand paper
maculous-papulous, erythema
Single roseols
Small maculous
Rare
(in case of B hepatitis)
Catarrhal sign
Typical
Absent
Absent
Rare
Typical
In the initial period
Changes in the throat
Hyperemia of the back pharyngeal wall
Tonsillitis
Tonsillitis Hyperemia of the back pharyngeal wall, posterior rhinitis
Hyperemia of the palatal arch, back pharyngeal wall
Herpangina
Absent
Joints’ damage
Arthritis, arthralgias
Not typical
Absent
Absent
Absent
Arthralgias in the initial period
Abdominal pain
Around the navel
Absent
Absent
In the right inguinal region
Around the navel
In the right hypochondria
Dyspeptic syndrome
Typical

Rare
Absent
Constipation, rare - diarrhea
Typical
More intensive in prodromal period

Hepatitis
May be
Absent
May be
Absent
Absent
Typical

Lymphoproliferative
May be
Regional lymphadenitis
Typical
Hepato- and splenomegaly
Absent
Hepato-, rare - splenomegaly
Tongue
Coated, strawberry from the 4th-5th day
Coated, strawberry from the 4th-5th day
Coated
Coated with grey,
teeth excavation on its’ borders
Coated
Coated
Damage of the nervous system
May be
Not typical
Not typical
Delirium, sopor
May be serous meningitis,
encephalitis
(rare)
Hepatic encephalopathy in severe case

Differential diagnostic of tonsillitis different etiology

Signs
Diphtheria of the pharynx
Scarlatina
Infectious mononucleosis
Streptococcus (staphylococcus) tonsillitis
Beginning
acute
acute
acute
acute
Leading symptoms
fibrinous inflammation in a throat, toxic syndrome
tonsillitis,exanthema from1-2 dayFilatov’s sign, 
toxic syndrome
Lymphoproliferative syndrometonsillitis is not obvious (secondary)
Tonsillitis (follicle,lacunar, necrotizing, toxic syndrome
Throat changes
Cyanotic hyperemia, edema
Bright "blazing" hyperemia marked off from the hard palate
Absent or bright hyperemia
Bright hyperemia
Character of tonsilar exudates
Grey-white, or yellow membranes, can spread outside the tonsils, are dense, hardly removed, mucus membranes bleeds under them, after the removal arise up again, are not separated
purulent in follicles or in lacunas, keep only on the tonsils, is easily taken off, mucus membranes does not bleed, are separated
purulent in follicles or in lacunas, white-yellowish, keep only on the tonsils, is easily taken off, mucus membranes does not bleed, are separated
purulent in follicles or in lacunas, white-yellowish, keep only on the tonsils, is easily taken off, mucus membranes does not bleed, are separated
Lymphadenitis


Regional
Regional
General
Regional
Hepatosplenomegaly
Absent
Absent
Typical
Absent
Rashes

Absent
Pin-point, red
Maculous-papulous may be erythema in 70-80% of patients, who take semisynthetic penicillins
Absent
Toxic sign
Proportional to the surface of the inflammatory process (mild, moderate or severe
Severe in the first days
Prolong with gradual development (moderate or severe)
moderate or severe in the first days
Subcutaneous fat edema

Typical for toxic forms
Absent
Upon the regional lymph nodes in severe cases
Absent
Changes on the tongue
Coated
Coated, strawberry from the 4-5th day
Coated
Coated

 

Treatment

Reduction of activity and bed rest.

special diet (diet N 5),
Exclude heavy fats (like pork), spices, fried foods, "fast food"”; avoid stimulators of gastrointestinal secretions, the diet must be rich by metionine, lecithin, and choline to stimulate synthesis of proteins and enzymes in the liver. Diet with normal value of proteins and vitamins, with restriction of fats and carbohydrates is administered, also restrict salt.
Foods boiled, steamed and baked are recommended; food taking 5 times daily

Control of fever and myalgia (when the temperature is more than 38.5-39˚C); in children before 2 mo and in case of perinatal CNS damage, seizures in the history, severe heart diseases – when the temperature is up to 38˚C with acetaminophen (paracetamol 10-15 mg/kg not often than every 4 hours (not more than 5 times per day) or ibuprophen 10 mg/kg per dose, not often than every 6 hours. Aspirin is contraindicated for children before 12 years.

Antihistamines (in average doses) – pipolphen, suprastin, claritin, cetirizin.

Corticosteroids - in severe cases 1-2 mg/kg/day prednisone for 3-5 days.

In case of secondary bacterial complications macrolides (erythromycin 30-50 mg/kg/day, azythromycin 10 mg/kg/day, clarythromycin) or cefalosporins (cefalexin 50 mg/kg/day, cefuroxim 50 mg/kg/day, cephasolin 100 mg/kg/day), Ampicillin and other semisynthetic penicillins are contraindicated!

The administration of oral acyclovir does not significantly alter the course of clinical illness from placebo.

 

Prophylaxis: is nonspecific, includes disinfecting;

Isolation of the patient, hospitalization of children younger 1 year, in case of severe forms.

A quarantine is not imposed.

Key words and phrases: infectious mononucleosis, EBV-infection, lymphoprolipherative syndrome, atypical mononuclear cells, heterophyl  agglutination test, and “mononucleosis” syndrome.

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