Enfermedades exantemáticas virales: aspectos clinicoepidemiológicos y de laboratorio / Exanthematous viral diseases: clinical and laboratory aspects

Los cuadros exantemáticos tienen frecuentemente origen infeccioso; los virus son una causa importante de exantema. Los exantemas más relevantes son, entre los maculopapulosos, el sarampión, la rubéola, el eritema infeccioso y el exantema súbito y, entre los vesiculoampollosos, la varicela, el zóster y la enfermedad boca-mano-pie. Algunas de las anteriores, y otras infecciones virales, causan exantemas purpúricos que pueden ser de mayor gravedad. El diagnóstico de laboratorio se realiza de forma directa, mediante el aislamiento, la detección de antígenos o la detección del ácido nucleico viral, siendo esta última la aproximación más adecuada; o, serológicamente, por detección de IgM específica, que proporciona diagnóstico temprano, o de seroconversión. En general, ambas herramientas metodológicas se complementan para mejorar el rendimiento diagnóstico. La caracterización molecular es una importante actividad de laboratorio, especialmente para los virus del sarampión y de la rubéola, en el contexto del plan de eliminación de estas enfermedades (AU)

Exanthematous diseases frequently have an infectious origin; viruses are a major cause of rashes. The most notable maculopapular rashes are measles, rubella, infectious erythema and exanthem subitum, while the vesicular rashes include varicella (and zoster) and hand-foot-and-mouth disease. Some of the above and other viral infections cause purpuric rashes, which may be more severe. Laboratory diagnosis is performed directly, by viral isolation, antigen detection or viral nucleic acid detection, the latter being the best approach; or serologically, by detection of specific IgM (providing rapid diagnosis) or seroconversion. Both methodological tools generally complement each other to improve diagnostic performance. Molecular characterization is an important laboratory procedure, especially for the measles and rubella viruses, in the context of the plan for the elimination of these diseases (AU)

Children Hospitalized With Varicella in Denmark: Sensitivity of the National Patient Register.

BACKGROUND: Varicella, common in childhood and most often self-limiting, may cause complications including bacterial superinfection, pneumonia and encephalitis. Universal childhood varicella vaccination has been introduced in several countries, but is controversial in Europe. In Denmark, varicella is not part of the national immunization program and there is no national surveillance of varicella. The primary aim of the study was to describe the epidemiology and clinical characteristics of children hospitalized with varicella in Denmark. The secondary aim was to validate the sensitivity and completeness of the Danish National Patient Register. METHODS: Active surveillance of children hospitalized with varicella was carried out at 4 pediatric departments. In the Danish National Patient Register, we identified all children discharged with an International Classification of Diseases, 10th revision code of varicella from the 4 departments. We used a capture-recapture analysis to estimate the "true" number of hospitalized children with varicella. RESULTS: By active surveillance, we identified 86 children eligible for clinical description. In 87% of cases, the children were 0-4 years of age. Complications were identified in 69% of patients, including 1 child with postvaricella cerebral angiopathy. In the National Patient register (NPR), we identified 125 children with a discharge diagnosis of varicella. By capture-recapture analysis, the sensitivity of the NPR was estimated to be 74%. CONCLUSIONS: Varicella can cause serious complications including cerebral angiopathy in children in Denmark. The NPR will be a useful tool for estimating hospitalization incidence, but will underestimate the true number of hospitalizations.

Varicella-related musculoskeletal complications in children.

Eight children with post-varicella musculoskeletal complications were treated between 2001 and 2009. The complications that were observed were cellulitis (three children), pyomyositis (three children), osteomyelitis (two children) and gangrene (one child). On average, 8.8 days elapsed between primary varicella infection and complication. The most common presentation was pain. Before we started treating them, all children received antibiotics during interhospital transfers (average: 2.4). Interventions included drainage (eight), fasciatomy (one), arthrotomy (one), bone drilling (one), and amputation (one). Blood cultures were negative in all children. Two children had positive pus cultures for Staphylococcus aureus, one of them had a methicillin-resistant S. aureus infection. One of the four children who developed coagulopathy ended with significant morbidity. Varicella-related methicillin-resistant S. aureus osteomyelitis suggests a widening spectrum of these infections.

Adult varicella zoster infection complicated with streptococcal retrosternal abscess.

A 43-year-old lady with type 2 diabetes mellitus and bronchial asthma presented with varicella zoster infection, dyspnea, and neck fullness. An urgent computed tomography scan revealed a mediastinal abscess with superior vena cava thrombus. Blood, mediastinal pus, and swab from a vesiculopustule on the neck cultured group A beta hemolytic Streptococcus. She recovered with a combination of broad spectrum antimicrobials, antivirals, and surgical drainage. This case illustrates the rare occurrence of mediastinal abscess and acute superior vena cava obstruction caused by group A beta hemolytic Streptococcus complicating adult varicella zoster.

Fatal streptococcal toxic shock syndrome in a child with varicella and necrotizing fasciitis of the face.

The report described here presents a fatal streptococcal toxic shock syndrome secondary to a necrotizing fasciitis of the face in a 3-year-old girl with varicella. Pathogenesis and treatment of streptococcal toxic shock syndrome are discussed below.

Bacterial skin infections in children hospitalized with varicella: a possible negative impact of non-steroidal anti-inflammatory drugs?

This 1-year multicentre prospective study in northern France sought to evaluate the incidence of secondary bacterial skin complications related to varicella, describe these superinfections, and analyse risk factors for their onset. The study included every child admitted to a district paediatric unit with a varicella infection. Patients with varicella infection, with and without secondary bacterial skin complication, were compared. The study included 159 children, 43 of whom had a secondary bacterial skin complication on admission, 21 of them had a severe secondary bacterial skin complication (respective incidence: 7.5 and 3.7/100,000 children younger than 16 years old). Persistence or recurrence of fever > or =38.5 degrees C for > or =3 days after the beginning of varicella infection (adjusted odds ratio (aOR)=8.1; 95% confidence interval (CI): 2.3-28.4) and the use of non-steroidal anti-inflammatory drugs (aOR=4.8; 95% CI: 1.6-14.4) were independent factors associated with severe secondary bacterial skin complication.

Lesiones de varicela en cavidad bucal: reporte de un caso / Chicken pox lesions in oral cavity: report of a case

La Varicela es una enfermedad viral que se presenta con frecuencia en la población infantil, cursa con lesiones cutáneas y en ciertas ocasiones en cavidad bucal. Se presenta un caso de paciente masculino de 5 años de edad, quien consulta por presentar lesiones en cavidad bucal, ademàs de las lesiones cutáneas. Fue tratado con antivirales tópico y sistémico, notándose mejoría de las lesiones en dos semanas.

The Chicken pox is a viral infection that is presented frequently in the infantile population, it presented with skin lesions and, in certain occasions, in oral cavity. A 5 years old male patient, who consult for present vesicles in oral cavity and skin lesions, it was treated with topical and systemic antiviral, being noticed improvement of the lesions in two weeks.

Varicella complicated by group A streptococcal sepsis and osteonecrosis.

A 5-year-old boy presented with primary varicella zoster virus infection, group A streptococcal sepsis, toxic shock, and multisite osteonecrosis. An association between osteonecrosis and group A streptococcal sepsis has not been previously reported. Clinical recognition with supportive radiologic and pathologic findings are presented. Therapeutic guidelines are suggested.

Low risk of bacteremia in febrile children with recognizable viral syndromes.

BACKGROUND: Previous studies of occult bacteremia in febrile children have excluded patients with recognizable viral syndromes (RVS). There is little information in the literature regarding the rate of bacteremia in febrile children with RVS. OBJECTIVE: To determine the rate of bacteremia in children 3 to 36 months of age with fever and RVS. METHODS: We performed a retrospective analysis of all patients 3 to 36 months of age with a temperature > or =39 degrees C seen during a 5 1/2-year period in the Emergency Department of a tertiary care pediatric hospital. From this group those with a discharge diagnosis of croup, varicella, bronchiolitis or stomatitis and no apparent concomitant bacterial infection were considered to have an RVS. The rate of bacteremia was determined for those subjects with RVS who had blood cultures. RESULTS: Of 21,216 patients 3 to 36 months of age with a temperature > or =39 degrees C, 1347 (6%) were diagnosed with an RVS. Blood cultures were obtained in 876 (65%) of RVS patients. Of patients who had blood cultures, true pathogens were found in only 2 of 876 (0.2%) subjects with RVS [95% confidence interval (CI) 0.01, 0.8%]. The rate of bacteremia was 1 of 411 (0.2%) for subjects with bronchiolitis, O of 249 (0%) for subjects with croup, O of 123 (0%) for subjects with stomatitis and 1 of 93 (1.1%) for subjects with varicella. CONCLUSIONS: Highly febrile children 3 to 36 months of age with uncomplicated croup, bronchiolitis, varicella or stomatitis have a very low rate of bacteremia and need not have blood drawn for culture.

[Osteomyelitis as a complication of varicella]. / Osteomyelitt som komplikasjon ved varicella.

Osteomyelitis is a rare complication after varicella. It should, however, be considered in any child who develops pain in a limb during or after a varicella infection. An 18 month old boy with a five day history of varicella infection was hospitalized. Movement of his right arm made him cry intensively. Blood cultures showed growth of group A beta haemolytic streptococcus. The day after admission to hospital the bone scintigrams showed increased activity in the right humeral diaphysis consistent with osteomyelitis, and penicillin therapy was started. On radiograms of the right humerus performed on the second day, no pathological changes could be shown. Radiograms after ten days showed irregular osteolytic lesions in the upper part of the humeral diaphysis. Clinically, the boy improved rapidly and could be dismissed from hospital after 17 days. Follow-up radiograms showed slowly normalized conditions, and five months after the start of symptoms, no pathological changes should be demonstrated.

Bacterial complications of primary varicella in children.

Bacterial complications of varicella in 84 patients younger than 16 years of age (48 females; median age, 2.9 years) who required hospitalization between 1985 and 1995 were retrospectively analyzed. The purpose of the study was to describe demographics, clinical manifestations, bacteriology, and factors affecting outcome. Seventy-six percent of patients were younger than 5 years of age. The eldest children in households were significantly underrepresented (P = .00025). Skin infections occurred in 61 patients (73%), and deep-seated infections and/or shock occurred in 23 (27%). The latter complications were significantly associated with thrombocytopenia (P = .011) and bacteremia (P = .014) at the time of admission, prolonged fever (P = .001), prolonged hospitalization (P < .0001), intensive care management (P < .0001), and fatal outcome (P = .019). Group A beta-hemolytic streptococcus (59% of isolates) and Staphylococcus aureus (28%) were the predominant isolates. Before and after 1990, five (31%) of 16 and 13 (62%) of 21 streptococcal complications, respectively, were invasive infections (P = .09). These data underscore the need for universal immunization against chickenpox.

Varicella-zoster virus (VZV) reactivation is related to the low response of VZV-specific immunity after chickenpox in infancy.

To clarify the cause of herpes zoster in immunocompetent children, specific humoral and cellular immunity was determined using an ELISA and a lymphoproliferative assay, respectively, in infants < 1 year of age and children > or = 1 year of age who had chickenpox. Thirteen (59.1%) of 22 infants, 17 (81.0%) of 21 children > or = 1 year of age (P < .02), and 13 (86.7%) of 15 children > or = 2 years of age (P < .001) had positive varicella-zoster virus (VZV)-specific cellular immunity. VZV-specific antibodies in infants were significantly lower than those in children > or = 1 year old (P < .01) and > or = 2 years old (P < .001). The possibility of subclinical reactivation was demonstrated by an increase in the specific cellular or humoral immunity (or both) in all of 6 infants who had negative specific cellular immunity. The low response of specific immunity and the immunologic evidence of reactivation in infants after chickenpox provide a possible explanation for the finding that chickenpox in infancy is a risk factor for herpes zoster.

Varicella-zoster virus replication site in internal organs of an otherwise healthy child with varicella and sudden death.

Pathological findings of an otherwise healthy 17 month old boy who was exposed to Varicella-zoster virus (VZV) in his family and unexpectedly died 3 days after onset of varicella are reported. They showed a disseminated VZV infection with involvement of skin, lung, liver, spleen, gastrointestinal tract and other organs where VZV antigen was detected by the enzyme-immunoassay with monoclonal antibodies to VZV. Since the subject was the full-term product of an uncomplicated pregnancy, who grew and developed normally, and had no symptoms or laboratory findings suggestive of immunodeficiency until his death, these findings suggest that many organs are involved as major internal sites of viral replication before or during infection of skin with VZV in the immunocompetent host.

Comparative analysis of the restriction endonuclease profiles of the Dumas and Singapore strains of varicella-zoster virus.

The incidence of varicella in Singapore has been increasing since 1984. In 1991, 17,930 cases were reported in a population of about 3 million. A serological survey completed in 1990 demonstrated that only 43% of the cohort had antibodies to varicella-zoster virus (VZV), indicating inadequate herd immunity. To exclude novel VZV strains, representative VZV isolates from 9 chicken pox and 4 zoster patients were characterised by restriction endonuclease analysis. DNAs were extracted from viral isolates propagated in MRC5 human embryo lung cells and were digested separately with BglII, EcoRI, PstI, SalI, and XbaI enzymes. The cleavage profiles of these VZV strains derived from both chicken pox and zoster lesions revealed no distinct differences. This observation implies that the current upsurge of chicken pox most likely stems from closely related VZV genotypes infecting a susceptible population with insufficient herd immunity. Comparison of the restriction fragments of the Singapore and the Dumas strains revealed polymorphisms of the SalI-D, SalI-E, and XbaI-I fragment lengths, which correlated with variable regions I, II, and III of the VZV genome, thereby representing geographically distinct genotypic variants of VZV.