An exanthematic disease epidemic associated with coxsackievirus B3 infection in a day care center

An epidemic of exanthematic illness in a day care center is described. Ten children aged 7 to 13 months were affected by the illness. The exanthem was characterized by nonconfluent macular or maculopapular lesions that appeared on the face, body and limbs. Fifty percent of the infected children had fever of up to 39ºC at the beginning of the disease. Coxsackievirus B3 (CB3) was isolated from the stool of one ill child. Paired serum samples were obtained from eight ill children and six of them presented seroconversion to CB3. Antibodies to CB3 were detected at titers higher than 16 in a single serum sample collected from the other two patients. Neutralizing antibodies to CB3 were detected in 71.0% of the contact children.

Drug resistance of M. Tuberculosis isolated from patients with HIV infection seen at an AIDS Reference Center in São Paulo, Brazil

M. tuberculosis-positive cultures were obtained from 228 patients seen in our service and drug sensitivity assays were carried out from January 1992 to December 1994. A survey of the medical records of these patients showed resistance to one or more drugs in 47 (20.6%), 25 of whom (10.9%), who reported previous treatment, were considered to have acquired resistance. Among the antecedents investigated, only previous treatment and alcoholism were the factors independently associated with the occurrence of resistance. The survival of patients with resistant strains was lower than that of patients attacked by non-resistant M. tuberculosis. We conclude that in the present series M. tuberculosis resistance to tuberculostatic agents was predominantly of the acquired type.

Cytomegalovirus infection in a day-care center in the municipality of São Paulo

The prevalence of antibodies against cytomegalovirus (CMV) and the incidence of CMV infection were tested in 98 children aged 5 to 36 months who attended the day-care center of a University hospital in São Paulo. At the beginning of the study the overall prevalence of anti-CMV IgG antibodies was 44% (43/98). Saliva and/or urine samples were obtained from 38 of the 43 children that were seropositive at the beginning of the study for isolation of the virus, and 52.6% of these children were found to excrete CMV in one of the two materials. Among the 37 children that were initially seronegative from whom it was possible to obtain a new blood sample 6 to 12 months later, 22 (59.5%) presented seroconversion. The rate of viral excretion through urine or saliva from the children that seroconverted was 50%. These results indicate that CMV infection is frequent and occurs early among the children who attend this day-care center. However, controlled studies using molecular epidemiology techniques are needed to define more precisely the role of day-care centers in CMV dissemination.

Active replication of hepatitis B virus (HBV) in HIV type 1 and in HIV type 2 infected patients

To evaluate the effect of concurrent infection by HIV on HBV infection or immunity, we have studied a group of 66 HIV1+ symptomatic Caucasian patients and another of 38 African HIV2+ asymptomatic individuals, concerning their HBV status: serological markers of infection and presence of HBV-DNA in serum, the last taken as sign of hepatitis B virus active replication, were monitored. HIV+ groups were compared with seronegative controls, adequately matched for age, sex and ethnological background. HBV DNA was found in 7.6% of HIV1+ Caucasian patients and 3.2% of seronegative controls; in African HIV2+ individuals 2.6% were also HBV DNA+, a percentage close to that found in HIV2 seronegative controls (2.9%). No correlation was found between HIV infection and HBV active replication. Immunodepression that follows HIV infection over time may be compatible with a degree of T cell function capable of avoiding reinfection with or reactivation of HBV, even in symptomatic stages of acquired immunodeficiency syndrome. Our findings are relevant to the choice of preventive strategies in populations at risk for HIV and HBV infection.

Cytomegalovirus infection in children with Down syndrome in a day-care center in Brazil

This study evaluates the transmission of CMV infection in 120 children aged 1 to 15 years with Down syndrome who attended a day-care center for handicapped children in São Paulo, Brazil. A blood sample was obtained from each children at the beginning of the study for detection of IgG and IgM cytomegalovirus (CMV) antibodies by an immunofluorescence assay. Samples of saliva and urine were obtained every 3 months from the children with CMV antibodies to detect shedding of the virus by culture in human foreskin fibroblasts, by detection of pp65 CMV-antigen and by a nested PCR assay. The prevalence of anti CMV-IgG antibodies was 76.6% (92/120), and IgM anti-CMV antibodies were detected in 13% (12/92) of the seropositive children. During the first viral evaluation, CMV was detected in the urine and/or saliva in 39/90 (43.3%) of the seropositive children. In the second and third evaluations, CMV was detected in 41/89 (46%) and in 35/89 (39.3%) children, respectively. Detection of CMV was shown both in urine and saliva in 28/39 (71.8%), 19/41(46.3%) and 20/35 (57.1%) of the children excreting the virus, respectively. Additionally, in 33/49 (67.4%) of the excreters CMV could be demonstrated in urine or saliva in at least two out of the three virological evaluations carried out sequentially in a six month period. Of the 28 initially seronegative children, 26 were re-examined for anti-CMV IgG antibodies about 18 months after the negative sample; seroconversion was found in 10/26 (38.5%). Taking all 536 samples of urine or saliva examined by virus culture and pp65 antigen detection during the study into account, 159 (29.6%) were positive by virus culture and 59 (11%) gave a positive result with the pp65 assay. These data demonstrate the high prevalence of CMV shedding and the high risk of CMV infection in children with Down syndrome attending a day-care center for mentally handicapped patients. The virus culture was more sensitive than the pp65 CMV antigen assay for CMV detection in both urine and saliva samples.

Evidence of active herpesvirus 6 (variant-A) infection in patients with lymphadenopathy in Belém, Pará, Brazil

A total of 323 patients with lymphadenopathy were selected in Belém, Brazil, between January 1996 and December 2001, and screened for the presence of human herpesvirus-6 (HHV-6) IgM- and- IgG antibodies by enzyme-linked immunosorbent assay (ELISA). When seroprevalence is analyzed by gender, similar rates are found for female (60.6%) and male (55.7%) individuals. Seventy-seven (23.8%) patients were HHV-6-IgM-and- IgG-positive (IgM+ subgroup), with positivity rates of 29.7% and 17.7% (p = 0.0007) for female- and male individuals, respectively. Sera from a subgroup (n = 120) of these subjects, with high HHV-6 antibody levels (either IgM+ or IgG+ reactivities), were subsequently processed for the presence of HHV-6 DNA by polymerase chain reaction (PCR)/nested PCR. Active infections (IgM+ and/or IgG+ high levels specific antibodies plus detection of viral DNA) were diagnosed in 20/77 (20.0%) and 8/43 (18.6%); subgroup of the 120 individuals suspected of having HHV-6 suggestive recent infection. All (n = 28) cases of active infection were found to be associated with HHV-6 variant-A (HHV-6A), as detectable by PCR/nested PCR, using variant-specific primer that amplify regions of 195 base pairs (bp) (HHV-6A) and 423 bp (HHV-6B). Rates of HHV-6 DNA detection between female and male patients were similar (p > 0.05) in the IgM+ and IgG+ groups: 20.4% versus 35.7% and 25.0% versus 13.0%, respectively. HHV-6 DNA was detected across < 5 through 41-50-year age-groups for patients whose serum samples were IgM+, with rates ranging from 7.7% (female subjects aged < 5 years) to 80.0% (male, 11-20 years). Among patients whose serological status was IgG+, HHV-6 DNA was detected in < 5, 6-10, 21-30 and > 50 age-groups at rates that ranged from 15.4% (male, < 5 years of age) to 100.0% (female aged 11-20 years). Swelling cervical lymph nodes were the most common sign, accounting for 9 (32.0%) cases in each gender group. Among patients (n = 28) with active infection by HHV-6A variant, duration of symptoms lasted 1-5 days in 35.7% of subjects, whereas in 64.3% of them the disease lasted 6-20 days. Our data suggest that it is worth seeking for HHV-6 infection whenever a patient (infant or adult) presents with lymphadenopathy as a prominent symptom in the course of an acute febrile illness.

Analysis of HIV- type 1 protease and reverse transcriptase in Brazilian children failing highly active antiretroviral therapy (HAART)

The aim of this study was to evaluate the genotypic resistance profiles of HIV-1 in children failing highly active antiretroviral therapy (HAART). Forty-one children (median age = 67 months) receiving HAART were submitted to genotypic testing when virological failure was detected. cDNA was extracted from PBMCs and amplified by nested PCR for the reverse transcriptase and protease regions of the pol gene. Drug resistance genotypes were determined from DNA sequencing. According to the genotypic analysis, 12/36 (33.3%) and 6/36 (16.6%) children showed resistance and possible resistance, respectively, to ZDV; 5/36 (14%) and 4/36 (11.1%), respectively, showed resistance and possible resistance to ddI; 4/36 (11.1%) showed resistance to 3TC and D4T; and 3/36 (8.3%) showed resistance to Abacavir. A high percentage (54%) of children exhibited mutations conferring resistance to NNRTI class drugs. Respective rates of resistance and possible resistance to PIs were: RTV (12.2%, 7.3%); APV (2.4%, 12.1%); SQV(0%, 12.1%); IDV (14.6%, 4.9%), NFV (22%, 4.9%), LPV/RTV (2.4%, 12.1%). Overall, 37/41 (90%) children exhibited virus with mutations related to drug resistance, while 9% exhibited resistance to all three antiretroviral drug classes.

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 Cryptosporidium sp. in non diarrheal faeces from children, in a day care center in the city of São Paulo, Brazil

The protozoan Cryptosporidium sp. has been frequently detected in faeces from children with persistent diarrhoea. This work achieved to investigate an outbreak of cryptosporidiosis, in a day care center, attending children of high socio-economic level, between 0 and six years old. The outbreak was detected through the network of public health, when stool samples, not diarrhoeic, were examined at the Parasitology Service of the Adolfo Lutz Institute. Among the 64 examined children, 13 (20.3%) showed oocysts of Cryptosporidium sp. in the faeces examined by Kinyoun technique: seven children one year old, three, two years old and three, three years old. Among the 23 examined adults, only a 22 years old woman, possibly having an immunocomprometiment, was positive. Clinical and epidemiological aspects were investigated by questionnaires, highlighting the occurrence of the outbreak in a very dry period.

Frequency and risk factors for toxocariasis in children from a pediatric outpatient center in southeastern Brazil

To estimate the frequency of anti-Toxocara sp. antibodies, and evaluate factors associated with this infection, sera from 242 male and female children, aged from one to fifteen years old, attended at the Hospital of the Federal University of Uberlândia, Minas Gerais State, Brazil, were analyzed by ELISA. Information on the patients was collected and registered using an investigative questionnaire, and details on possible clinical alterations were obtained from the medical charts of 187 patients. Of a total of 242 samples, 21 (8.7%) were positive for anti-Toxocara sp. antibodies. The presence of dogs and cats and the school variable (place of contact), appeared to be significantly associated (p < 0.05) with a positive serology. Respiratory symptoms and eosinophil counts greater than 20% also showed a positive statistical correlation with a positive serology for Toxocara sp.. Factors such as sex and age, and symptoms like headache, stomach ache, convulsive crises and anemia were not associated with toxocariasis.

Asymptomatic oral carriage of Candida species in HIV-infected patients in the highly active antiretroviral therapy era

Oropharyngeal candidiasis is the most common opportunistic fungal infection in individuals infected with human immunodeficiency virus. CD4+ lymphocytes count and the quantification of viral RNA in blood plasma have been found to be the main markers of HIV disease progression. The present study was conducted to evaluate Candida sp. diversity in the oral cavity of HIV-infected patients and to determine whether there was association of CD4+ cell count and viral load with asymptomatic oral Candida carriage. Out of 99 HIV-positive patients studied, 62 (62.6%) had positive culture for Candida (oral carriage) and 37 patients (37.4%) had Candida negative culture (no oral carriage). The etiologic agents most common were C. albicans and C. tropicalis. The range of CD4+ was 6-2305 cells/mm³ in colonized patients and 3-839 cells/mm³ for non-colonized patients, while the viral load was 60-90016 copies/mL for colonized patients and 75-110488 copies/mL for non colonized patients. The viral load was undetectable in 15 colonized patients and in 12 non colonized patients. Our results showed that there was no significant difference of the variables CD4+ cell count and viral load between oral candida carriage and no oral candida carriage patients.

Comparison of serology, antigenemia assay and the polymerase chain reaction for monitoring active cytomegalovirus infections in hematopoietic stem cell transplantation patients

Forty-six allogeneic hematopoietic stem cell transplantation (HSCT) patients were monitored for the presence of CMV antibodies, CMV-DNA and CMV antigens after transplantation. Immunoenzymatic serological tests were used to detect IgM and the increase in CMV IgG antibodies (increase IgG), a nested polymerase chain reaction (N-PCR) was used to detect CMV-DNA, and an antigenemia assay (AGM) was used to detect CMV antigens. The presence of CMV-IgM and/or CMV-increase IgG antibodies was detected in 12/46 (26.1%) patients, with a median time between HSCT and the detection of positive serology of 81.5 days. A positive AGM was detected in 24/46 (52.2%) patients, with a median time between HSCT and antigen detection of 62 days. Two or more consecutive positive N-PCR results were detected in 32/46 (69.5%) patients, with a median time between HSCT and the first positive PCR of 50.5 days. These results confirmed that AGM and mainly PCR are superior to serology for the early diagnosis of CMV infection. Six patients had CMV-IgM and/or CMV-increase IgG with a negative AGM (five cases) or N-PCR assay (one case). In five of these cases the serological markers were detected during the first 100 days after HSCT, the period of highest risk. These findings support the idea that serology may be useful for monitoring CMV infections in HSCT patients, especially when PCR is unavailable.