Clinical and laboratory characteristics of infectious mononucleosis by Epstein-Barr virus in Mexican children.

BACKGROUND: Infectious mononucleosis (IM) or Mononucleosis syndrome is caused by an acute infection of Epstein-Barr virus. In Latin American countries, there are little information pertaining to the clinical manifestations and complications of this disease. For this reason, the purpose of this work was to describe the clinical and laboratory characteristics of infection by Epstein-Barr virus in Mexican children with infectious mononucleosis. METHODS: A descriptive study was carried out by reviewing the clinical files of patients less than 18 years old with clinical and serological diagnosis of IM by Epstein-Barr virus from November, 1970 to July, 2011 in a third level pediatric hospital in Mexico City. RESULTS: One hundred and sixty three cases of IM were found. The most frequent clinical signs were lymphadenopathy (89.5%), fever (79.7%), general body pain (69.3%), pharyngitis (55.2%), hepatomegaly (47.2%). The laboratory findings were lymphocytosis (41.7%), atypic lymphocytes (24.5%), and increased transaminases (30.9%), there were no rupture of the spleen and no deaths among the 163 cases. CONCLUSIONS: Our results revealed that IM appeared in earlier ages compared with that reported in industrialized countries, where adolescents are the most affected group. Also, the order and frequency of the clinical manifestations were different in our country than in industrialized ones.

Detection of EBV-DNA in serum samples of an immunosuppressed child during a three years follow-up: association of clinical and PCR data with active infection.

Twenty-four whole blood and serum samples were drawn from an eight year-old heart transplant child during a 36 months follow-up. EBV serology was positive for VCA-IgM and IgG, and negative for EBNA-IgG at the age of five years old when the child presented with signs and symptoms suggestive of acute infectious mononucleosis. After 14 months, serological parameters were: positive VCA-IgG, EBNA-IgG and negative VCA-IgM. This serological pattern has been maintained since then even during episodes suggestive of EBV reactivation. PCR amplified a specific DNA fragment from the EBV gp220 (detection limit of 100 viral copies). All twenty-four whole blood samples yielded positive results by PCR, while 12 out of 24 serum samples were positive. We aimed at analyzing whether detection of EBV-DNA in serum samples by PCR was associated with overt disease as stated by the need of antiviral treatment and hospitalization. Statistical analysis showed agreement between the two parameters evidenced by the Kappa test (value 0.750; p < 0.001). We concluded that detection of EBV-DNA in serum samples of immunosuppressed patients might be used as a laboratory marker of active EBV disease when a Real-Time PCR or another quantitative method is not available.

Detection of EBV-DNA in serum samples of an immunosuppressed child during a three years follow-up: association of clinical and PCR data with active infection

Vinte e quatro amostras de sangue total e de soro foram colhidas durante seguimento por 36 meses de criança de oito anos de idade, imunodeprimida devido a transplante cardíaco. O paciente apresentou VCA-IgG e IgM positivos e EBNA-IgG negativo aos cinco anos de idade quando foi diagnosticada mononucleose infecciosa. Quatorze meses depois o VCA-IgG e o EBNA-IgG eram positivos e o VCA-IgM negativo. Este padrão sorológico persiste desde aquela época mesmo durante episódios sugestivos de reativação. As amostras de sangue total e de soro foram analisadas pela Reação em Cadeia da Polimerase (PCR) que amplificou fragmento oriundo da gp220 do EBV (detecção de 100 cópias virais). Todas as 24 amostras de sangue total e 12 amostras de soro foram positivas por PCR. Com o objetivo de verificar se a detecção de DNA do EBV em soro estaria associada à reativação da doença, os resultados de PCR foram analisados em relação à necessidade de hospitalização e uso de anti-viral. O teste de Kappa mostrou que existe concordância entre a presença de DNA do EBV em soro e a necessidade de hospitalização e tratamento com anti-virais (valor de 0,750; p < 0,001). Concluímos que a detecção de DNA do EBV em amostras de soro de pacientes imunosuprimidos poderia ser usada como marcador laboratorial de atividade da infecção quando técnicas quantitativas de amplificação não estiverem disponíveis.

[Acute infections caused by Epstein-Barr virus. Comparative study of various diagnostic methods]. / Infección aguda por virus de Epstein-Barr. Estudio comparativo entre diversos métodos de diagnóstico.

Comparative performance of four methods (IFI, IgM anti-VCA, Organon Teknika; ELISA, IgM anti VCA, Incstar Corp and Pharmacia Diagnostic Inc; ELISA IgM against a group of several antigens which principal component is EBNA, Behring Institute) to detect antibodies (Abs) against Epstein-Barr virus in 180 patients (group 1) with infectious mononucleosis with no heterophil Abs (Organon Teknika), 180 healthy subjects with no heterophil Abs (group 2) and 20 patients with infectious mononucleosis (group 3) and with positive heterophil Abs, were studied. In group 1, 10% of patients had IgM Abs, without differences IgM Abs. In group 3 all patients had IgM Abs with no differences in the methods studied. There were no differences in the performance of the evaluated methods to detect IgM against different antigens, but those which use a group of antigens from the virus could be more useful in patients immunologic disorders.

[Hepatitis by infectious mononucleosis]. / Hepatitis por mononucleosis infecciosa.

Five adult patients presenting with clinical and laboratory manifestations of an acute hepatitis in the course of a hitherto undiagnosed infectious mononucleosis (IM) are reviewed. Chief complaints were intense malaise and prolonged fever (7 to 15 days prior to diagnosis). Serum aminotransferases were moderately raised in all patients; three patients had mild jaundice with a direct-reacting hyperbilirubinemia; 4 patients had an enlarged and tender liver. When making the differential diagnosis of causes of acute hepatitis, blood smear examination was crucial, showing atypical lymphocytes (Downey). The diagnosis of IM was confirmed by the demonstration of high serum titers of antibodies against Epstein-Barr virus, IgM class (4 patients) or heterophil antibodies (1 patient), plus peripheral lymph node enlargement (3 patients), splenomegaly (4 patients) and the time course of the disease. The relevance of blood smear examination as a practical tool in the diagnosis of causes of acute hepatitis is stressed.