WHEN A VIRUS HAS DIFFERENT FACES

Measles is a highly contagious viral illness, characterized by fever, malaise, cough, coryza and conjunctivitis, followed by maculopapular exanthema, which spreads cephalocaudally and centrifugally. Measles, mumps, rubella (MMR) vaccination has led to the interruption of measles virus transmission and gives protection to unvaccinated individuals via herd immunity. The morbilliform exanthema can be found in various conditions, including infectious mononucleosis. It is characterized by fever, pharyngitis, lymphadenopathy and a generalized maculopapular, urtical or petechial rash occasionally can be present, especially after administration of beta-lactams. CASE REPORT: 17 months old male was admitted in our pediatric department for the appearance, 4 days earlier, of rash and fever (T 38,8°C). The exanthema consisted of an erythematous, maculopapular, blanching rash, which began on the face and progressed to the truck and extremities involving the palms and soles. In some areas it showed confluent and hemorrhagic features. The physical examination showed the presence of laterocervical lymphadenopathy, nonpurulent conjunctivitis and pharyngitis. About 10 days earlier it was administered antibiotic therapy with Amoxicillin for a fever associated with malaise, cough and coryza. The child had no history of allergies and the MMR vaccine was repeatedly delayed and eventually not carried out for multiple episodes of respiratory infections. The laboratory tests showed leucocitosis with a normal differential count, mild elevation of transaminases, elevation of inflammatory markers and LDH; the morphological evaluation of the peripheral smear showed some activated lymphomonocitoid cells. Given the rash characteristics and the strong suspicion of measles, the patient was located in isolation and infectivological tests were performed (TORCH, Monotest, Respiratory Multiplex PCR panel and a serology for measles). They all came back negative except for the anti VCA IgM for EBV infection. The patient was treated with IV fluids and antipyretics. Antibiotic therapy was administered in order to prevent bacterial superinfections. After 72 hours the rash started to darken and then to gradually fade. The patient was dismissed with the diagnosis of maculopapular exanthema in mononucleosis infection. Clinical manifestations of infectious mononucleosis can be similar to those of measles and, especially in unvaccinated patients, can sometimes be confused with it. Maculopapular exanthema can be found in various conditions, such as common viral or bacterial infections, IgA vasculitis, Kawasaki disease or drug eruption. For this reason, it is important to consider mononucleosis in the differential diagnosis of measles, especially in case of hemorrhagic and infiltrated rash, not much described in the literature