Four-year safety follow-up of the tetravalent dengue vaccine efficacy randomized controlled trials in Asia and Latin America

OBJECTIVE

Our objective was to describe the risk of hospital admission for virologically confirmed dengue (VCD) and the risk of clinically severe hospitalized VCD occurring up to 4 years after the first dose (years 1 to 4) in three randomized clinical trials comparing tetravalent dengue vaccine with placebo.

METHODS

The relative risks (RR) for hospitalized VCD from first dose to year 4 were estimated by year and age-group in individual and combined studies.

RESULTS

Overall, from Year 1 to Year 4, 233 and 228 participants had at least one episode of hospitalized VCD in the vaccinated (n = 22 603) and placebo (n = 11 301) groups, respectively (RR = 0.511, 95% CI 0.42-0.62). Among these, 48 and 47 cases, respectively, were classified as clinically severe. In children aged ≥9 years, 88 and 136 participants had at least one episode of hospitalized VCD in the vaccinated (n = 17 629) and placebo (n = 8821) groups, respectively (RR = 0.324; 95% CI 0.24-0.43). In vaccinated participants aged <9 years, particularly in those aged 2-5 years, there were more hospitalized VCD cases compared with the control participants in Year 3 but not in Year 4. The overall RR in those aged <9 years for Year 1 to Year 4 was 0.786 (95% CI 0.60-1.03), with a higher protective effect in the 6-8 year olds than in the 2-5 year olds.

CONCLUSIONS

The overall benefit-risk remained positive in those aged ≥9 years up to year 4, although the protective effect was lower in years 3 and 4 than in years 1 and 2.

Neurological complications and death in children with dengue virus infection: report of two cases

Background

Dengue virus infection can have different complications; the best known is hemorrhagic dengue fever. However, other effects such as neurological disorders may endanger the lives of patients. Dengue neurological manifestations can be confused with encephalitis symptoms and can lead to cerebral edema and death. Therefore, we consider important in the endemic areas to take into account the diagnosis of dengue encephalitis in patients with neurological disorders, and to request the determination of serology in cerebrospinal fluid for the NS1 antigen test.

Case presentation

We present the cases of two patients from the state of Morelos, Mexico, with 17 and 14 years of age. Both cases presented a rapid evolution characterized by fever, seizures and neurological deterioration secondary to severe cerebral edema that evolved to cerebral death in both cases. The diagnosis of brain death was confirmed by electroencephalogram in both patients. The two patients were submitted to serology for NS1 that tested positive in both cases. They died between the second and fifth day after admission.

Conclusions

Retrospective studies have found that up to 4% of the patients have dengue virus infections, which leads us to believe that in endemic areas, this infection should be suspected in cases of encephalic and febrile symptoms. RT-PCR should be performed to identify cases of encephalitis caused by the dengue virus, and early interventions should be performed to attempt to reduce the morbidity and mortality of these cases.

Agua: la importancia de una ingesta adecuada en pediatría

El agua es el componente más abundante del cuerpo humano, que por sí mismo es incapaz de producirla en cantidades suficientes para satisfacer sus necesidades; por eso es vital consumir una cantidad adecuada para mantener la homeostasis. A pesar de que el agua es indispensable para la vida hay gran desconocimiento de los profesionales de la salud sobre el metabolismo de agua y las recomendaciones sobre la ingesta adecuada para una alimentación saludable. Se ha comprobado que los niños consumen menos líquidos de lo recomendado, persistiendo en ellos un estado de subhidratación que puede llegar a afectar su nivel de atención, su desempeño escolar, su estado de ánimo y su capacidad cognitiva. Por otra parte, los niños consumen gran cantidad de bebidas azucaradas al día, que exceden las recomendaciones diarias de calorías en líquidos; por lo tanto se deben instituir normas y medidas para garantizar un buen estado de hidratación en la población infantil, así como intervenciones para reducir el consumo de bebidas azucaradas en su dieta. 

Arbovirus en Latinoamérica

Las enfermedades producidas por arbovirus son un problema muy grave a nivel mundial, debido a que su vigilancia y prevención implica también la vigilancia de sus vectores, lo que hace difícil su control y casi imposible evitar su expansión a cualquier país tropical o subtropical, e incluso algunas regiones templadas. A nivel mundial, el  dengue es la enfermedad por arbovirus más común con 40% de la población mundial viviendo en zonas de transmisión del virus del dengue. De las 390 millones de infecciones estimadas y 100 millones de casos anuales, una proporción pequeña de estos casos progresa a dengue grave. Aproximadamente uno de cada 2,000 casos de dengue causan la muerte; sin embargo, la tasa de letalidad de los pacientes con dengue grave se puede reducir de casi 10% a menos del 0.1% si se actúa rápidamente y con calidad en la atención clínica que reciben los pacientes. Esto, aunado a la reciente y rápida propagación del virus chikungunya y el brote de virus zika en países latinoamericanos, como México, hace necesaria la actualización médica y revisión de bibliografía respecto a la prevención, control y gestión de las infecciones causadas por arbovirus. Por lo tanto, presentamos una revisión de lo más reciente sobre enfermedades por arbovirus en América Latina. 

Efficacy and Long-Term Safety of a Dengue Vaccine in Regions of Endemic Disease

BACKGROUND

A candidate tetravalent dengue vaccine is being assessed in three clinical trials involving more than 35,000 children between the ages of 2 and 16 years in Asian-Pacific and Latin American countries. We report the results of long-term follow-up interim analyses and integrated efficacy analyses.

METHODS

We are assessing the incidence of hospitalization for virologically confirmed dengue as a surrogate safety end point during follow-up in years 3 to 6 of two phase 3 trials, CYD14 and CYD15, and a phase 2b trial, CYD23/57. We estimated vaccine efficacy using pooled data from the first 25 months of CYD14 and CYD15.

RESULTS

Follow-up data were available for 10,165 of 10,275 participants (99%) in CYD14 and 19,898 of 20,869 participants (95%) in CYD15. Data were available for 3203 of the 4002 participants (80%) in the CYD23 trial included in CYD57. During year 3 in the CYD14, CYD15, and CYD57 trials combined, hospitalization for virologically confirmed dengue occurred in 65 of 22,177 participants in the vaccine group and 39 of 11,089 participants in the control group. Pooled relative risks of hospitalization for dengue were 0.84 (95% confidence interval [CI], 0.56 to 1.24) among all participants, 1.58 (95% CI, 0.83 to 3.02) among those under the age of 9 years, and 0.50 (95% CI, 0.29 to 0.86) among those 9 years of age or older. During year 3, hospitalization for severe dengue, as defined by the independent data monitoring committee criteria, occurred in 18 of 22,177 participants in the vaccine group and 6 of 11,089 participants in the control group. Pooled rates of efficacy for symptomatic dengue during the first 25 months were 60.3% (95% CI, 55.7 to 64.5) for all participants, 65.6% (95% CI, 60.7 to 69.9) for those 9 years of age or older, and 44.6% (95% CI, 31.6 to 55.0) for those younger than 9 years of age.

CONCLUSIONS

Although the unexplained higher incidence of hospitalization for dengue in year 3 among children younger than 9 years of age needs to be carefully monitored during long-term follow-up, the risk among children 2 to 16 years of age was lower in the vaccine group than in the control group. (Funded by Sanofi Pasteur; ClinicalTrials.gov numbers, NCT00842530, NCT01983553, NCT01373281, and NCT01374516.).

Beneficial effects of the n-3 long-chain polyunsaturated fatty acids in surgical patients: updating the evidence

The use of n-3 polyunsaturated fatty acids in surgical patients has risen by the fact that this may attenuate systemic and acute inflammatory responses secondary to surgical trauma through modulation of inflammatory mediators and cell membrane interactions. Moreover, the inclusion of n-3 fatty acids in clinical trials as part of the therapy in patients, who expect to undergo a surgical stress, suggests benefits on clinical progress. Therefore, the objective of this article is to review data from n-3 polyunsaturated fatty acid effects on biochemical parameters and on reduced length of hospitalization, number of infections, and mortality as main clinical outcomes in human surgical patients.

Fluoroquinolone resistance in clinical and environmental isolates of Escherichia coli in Mexico City

AIMS

To assess the different phenotypes and mechanisms of fluoroquinolone (FQ) resistance in clinical and environmental isolates of Escherichia coli.

METHODS AND RESULTS

We compared FQ-resistant E. coli isolates, measuring minimal inhibitory concentrations (MIC) of ciprofloxacin, along with susceptibility to other antibiotics. We also searched for the presence of efflux pumps, using efflux inhibitors, and for plasmid-borne FQ-resistance by PCR. We found that, aside from the higher FQ-resistance prevalence among clinical strains, environmental ones resist much lower concentrations of ciprofloxacin. Efflux pumps mediate fluoroquinolone resistance as frequently among environmental isolates than in clinical strains. Plasmid-borne qnrA genes were not detected in any resistant strain.

CONCLUSIONS

Environmental FQ-resistant strains may have a nonclinical origin and/or a selective pressure different from the clinical use of FQs.

SIGNIFICANCE AND IMPACT OF THE STUDY

The identification of the source of low-level FQ-resistant strains (ciprofloxacin MIC c. 8 microg ml(-1)) in the environment could be important to curb the rapid emergence and spread of FQ-resistance in clinical settings, as these strains can easily become fully resistant to FQ concentrations achievable in fluids and tissues during therapy.

High resistance prevalence towards ampicillin, co-trimoxazole and ciprofloxacin, among uropathogenic Escherichia coli isolates in Mexico City

BACKGROUND

The prevalence of antimicrobial resistance among uropathogenic E. coli varies widely worldwide; to guide empirical therapy is necessary to have local, up-to-date susceptibility data.

METHODOLOGY

We tested 907 isolates from patients in Mexico City by disk diffusion and further characterized ciprofloxacin, cephalosporin and nitrofurantoin resistant strains.

RESULTS

Isolates were mostly resistant to ampicillin (74%), trimethoprim-sulfamethoxazole (60.1%) and ciprofloxacin (32.6%). The most effective drug was netilmicin (5.1% resistant) and the most effective of oral drugs was nitrofurantoin (7.4% resistant). Sixty-percent of ciprofloxacin-resistant strains had minimal inhibitory concentrations of 125 microg/ml or higher, well beyond urinary concentrations at the end of the 12-hour inter-dose period for standard oral regimes. Extended-spectrum beta-lactamases were detected in 6% of strains, most of them from community-acquired infections. All strains resistant to nitrofurantoin carried a 20 Kb plasmid, which when transformed into a susceptible recipient, conferred resistance to nitrofurantoin, ampicillin, sulfonamides, streptomycin, and partially protected against ciprofloxacin.

CONCLUSIONS

Drugs considered of choice against uncomplicated urinary tract infections are facing high resistance prevalences and resistance determinants formerly seen only at hospitals are now among community strains. Treatment guidelines from developed countries might not reflect these local trends.

Neonatal outcome of children born to women with tuberculosis

BACKGROUND

As the incidence of tuberculosis (TB) has increased worldwide, it is expected that pregnant women will acquire this infection more frequently. Mycobacterium tuberculosis infection during pregnancy may represent a risk for maternal and neonatal complications.

METHODS

We studied the perinatal events of 35 consecutive pregnancies complicated by TB from March 1990 to June 1998; 105 apparently healthy pregnant women were included as controls, matched in age, gestational age upon arrival at the Institute, and socioeconomic status. Frequency and type of neonatal complications were recorded. Relative risk (RR) with 95% confidence interval (CI) was calculated. To control potentially confounding variables, a stratified analysis was performed.

RESULTS

Seventeen (48.5%) tuberculous mothers had a pulmonary infection and 18 (51.5%), an extrapulmonar localization of the TB. The neonatal morbidity rate in children born to women with TB was 23% against 3.8% of the children of the control cohort (p <0.05). Average weight of newborn infants of tuberculous mothers was 2,859 +/- 78.5 g, while average weight at birth of control neonates was 3,099 +/- 484 g (p = 0.03). Newborns of women with TB had a higher risk of prematurity (RR 2.1; 95% CI 1-4.3), perinatal death (RR 3.1; 95% CI 1.6-6), and weight at birth less than 2,500 g (RR 2.2; 95% CI 1.1-4.9). Pulmonary localization of the TB and late start of the treatment in the mothers increase the risk of perinatal death and neonatal morbidity.

CONCLUSIONS

Children born to women with TB have an increased risk of morbidity and mortality in the neonatal period.

[The outcome of pregnancies complicated by rubella, 1990-1997]

OBJECTIVE

To describe the experience of management of pregnant women complicated with rubella and to evaluate the perinatal outcome.

MATERIAL AND METHODS

A total of 67 pregnant women with positive IgM test for rubella were studied in the period from January 1st, 1990 to October 31st, 1997. Sixty-six of these women were followed until the end of gestation, in 4 patients an elective abortion was performed and 1 patient had a molar pregnancy. The effects of rubella on gestation and on the product were evaluated in sixty-one of the patients. Anti-rubella IgM was determined at birth and positive infants were subjected to evaluation by echocardiogram, brainstem auditory evoked potentials (BAEP) and ophthalmological study.

RESULTS

Mean age of the patients was 24.7 +/- 5.5 years; 28 patients were primigravidae. Pregnancies were normal showing no complications due to the rubella episode. In 35 cases (52.2%), the viral infection occurred during the first trimester of pregnancy, in 23 cases (34.5%) during the second and in 9 (13.3%) during the third. Seventy-one percent of infants born to mothers infected during the first trimester of pregnancy were also infected, and 51.6% developed congenital rubella syndrome. The most frequent manifestations of CRS were: prematurity, low birth weight and alterations of the BAEP.

CONCLUSIONS

In Mexico, rubella is still a cause of fetal damage, which shows the need for preventive strategies, such as universal vaccination, to avoid rubella infection during pregnancy.

Bacteriospermia and male infertility: a method for increasing the sensitivity of semen culture

OBJECTIVE

To test a method for increasing the sensitivity of semen culture. Design-Prospective and transverse. Setting-Andrology clinic at a tertiary care health institution in Mexico City.

PATIENTS

65 infertile patients with abnormal semen, bacteriospermia detected on Gram stain and at least two previous negative semen cultures (<3 months) were included to test routine semen culture and a method including centrifugation of semen at 10,00 rpm for 20 minutes. Localization cultures were also carried out in all patients.

MAIN OUTCOME MEASURE

Bacterial isolation in semen samples.

RESULTS

Routine semen culture was positive in 22% of patients, while centrifuged aliquots of the same semen sample were positive in 52% of patients (chi2 = 6.60, P < .01). Enterococcus was isolated in 43% of patients, E. coli in 24%, coagulase-negative Staphylococcus in 19%, and U. urealyticum in 14%. Ninety percent of isolates corresponded to specimens from the urethra and the prostato-vesicular region.

CONCLUSION

Sensitivity of semen culture increased with centrifugation of semen samples. Localization pattern and type of isolates suggest that these patients had chronic prostatitis and that episodic elimination of bacteria might also explain false negative semen cultures in patients with chronic asymptomatic infection of the accessory sex glands.

Amniotic fluid interleukin-6 and the risk of early-onset sepsis among preterm infants

BACKGROUND

High concentrations of interleukin-6 (IL-6) have been demonstrated in amniotic fluid (AF) from women with intra-amniotic infection. Recent studies have reported that IL-6 levels in AF were related to an increase in neonatal morbidity; moreover, higher IL-6 plasma levels have been observed in neonates with sepsis.

METHODS

A cohort study was carried out at the National Institute of Perinatology in Mexico City. Inclusion criteria were the following: 1) preterm singleton pregnancy; 2) intact membranes at time of enrollment, and 3) written informed consent. Women with other complications of pregnancy were excluded. Newborn sepsis during the first 72 h was defined as early-onset sepsis. Amniotic fluid was obtained at the moment of delivery. Amniotic fluid IL-6 (AF IL-6) was determined by enzyme-linked immunoassays.

RESULTS

Ninety-three women met the criteria for enrollment in the study and 31 (33%) of their newborns had early-onset neonatal sepsis. The mean AF IL-6 in mothers of septic newborns was 5779 +/- 2804 pg/ml compared to 729 +/- 382 pg/ml in mothers with non-infected neonates (p < 0.001). AF IL-6 concentrations higher than 1250 pg/ml were significantly associated with early-onset sepsis (OR 33.3; 95% CI 9.4-117.3) (p < 0.001). Gestational age under 32 weeks was also associated with neonatal sepsis (OR 2.56; 95% CI 1.2-9) (p = 0.002). Women whose infants developed neonatal sepsis had a higher frequency of clinical chorioamnionitis (p = 0.02).

CONCLUSIONS

IL-6 determination in AF may be a useful indicator to identify neonates with higher risk of in utero bacterial infection.

Infection of pregnant women with hepatitis B and C viruses and risks for vertical transmission

Pregnant women infected with hepatitis B and C viruses pose a risk for infecting their newborn infants by vertical transmission. We studied 6,253 pregnant women aged 12-49 years for infection with hepatitis B (HBV) and C (HCV) viruses. Infection was diagnosed by measuring IgG antibodies against HBc, HBs, HBe, as well as IgM-HBc and HCV viral antigens with commercially available immunoassay kits. HBV infection was detected in 113 cases (1.8%), and prevalence was significantly higher (2.4%) in a group of women with a high-risk pregnancy who were attending a perinatology hospital than in healthy pregnant women (1.67%, p < 0.05). Infection with HBV was significantly higher in women older than 30 years old (p < 0.05). HBsAg was found in blood, colostrum and vaginal exudate of two pregnant women; HBsAg was detected in the gastric aspirate but not in the blood of the two newborn infants. HBeAg and IgM-HBc were not detected in any of the samples. DNA-HBV was detected in serum of seven women, and DNA-HBV was detected in the gastric aspirate of only one of the newborns. HCV infection was diagnosed in three out of 111 women with markers for HBV infection (2.7%), and in 6 out of 1,000 women without these markers (0.6%). Anti-HCV antibodies were found in the serum of six of their infants during up to six months of age. Infants were monitored for one year and none of them developed any sign of hepatic disease. These results suggest that special attention should be paid to women older than 30 years and with a high-risk pregnancy, as they are at a higher risk of HBV and HCV infections.

Assessment of the functional capacity for intracellular death and phagocytosis of polymorphonuclear cells in healthy neonates

The objective of this study was to assess the functional capacity for intracellular death (ID) and/or phagocytic index (PI) of polymorphonuclear cells of 24-h-old healthy newborns with respect to the PMN cells of adults using the same standard exogenous source of opsonins. The ID and PI techniques were standardized and 2-3 ml of blood were used. No differences were found in the percentages of ID, P, PI among the PMNs of the newborns and those of the adults: 43.95 +/- 15.70 vs. 44.56 +/- 8.43 for ID; 38.96 +/- 14.34 vs. 39.00 +/- 14.54 for P; 1.71 +/- 0.54 vs. 1.73 0.45 for PI, respectively. It was concluded that the PMNs of 24-h newborns have an ID, P, PI functionality comparable to adult PMNs; differences observed in PMN function in newborns may be due to humoral deficiencies (opsonins).

[Prevalence of serologic markers of hepatitis A, B, C, and D viruses in pregnant women]

OBJECTIVE

To determine the seroprevalence of hepatitis A, B, C and D virus infection among pregnant women attending a perinatal care hospital.

MATERIAL AND METHODS

A prospective study was carried out to determine the seroprevalence of hepatitis A virus IgG antibodies (anti-HAV), hepatitis B virus markers (anti-HBcAg and HBsAg) and hepatitis C virus antibodies (anti-HCV) in pregnant women. In HBsAg positive cases. HBeAg and hepatitis D virus antibodies (anti-HDV) were investigated. All analyses were performed with the ELISA technique.

RESULTS

Of the 1500 pregnant women studied. 93.3% were positive for anti-HAV IgG. The HBsAg seroprevalence was 0.26% and anti-HCV seroprevalence was 0.53%. There were no patients with HBeAg or anti-HDV.

CONCLUSIONS

A higher seroprevalence of HBsAg was found in this study than in other studies of pregnant Mexican women. We propose that HBsAg screening become a routine prenatal test.

[Nosocomial infections of gynecologic-obstetrical origin at a perinatal care hospital]

Nosocomial infections (NI) are still a major cause of morbidity among gynecology & obstetrics patients (GOP). At the Instituto Nacional de Perinatología (INPer), during 1989, there was an overall NI rate of 2.37 per 100 GOP discharged, while specific NI rates for the subgroups of puerperal and gynecologic surgery patients were 2.11 and 6.3 respectively. Endometritis and infected surgical wounds were the most frequent type of NI, having a multimicrobial etiology. There was a significant increase in hospital days of stay for those patients who developed NI. It is clearly necessary to improve the surveillance of NI as well as the collaboration among different wards dealing with GOP, in order to find more effective and efficient ways to prevent the development of NI.

[Neonatal conjunctivitis caused by Chlamydia trachomatis]

32 newborns with neonatal Chlamydia trachomatis conjunctivitis were reported. Diagnosis was carried out through immunofluorescent monoclonal antibody of conjunctiva scraping staining; 37 conjunctiva samples were taken from same number of newborn patients not responds to topical antibiotic treatment. The sample came out from two different third level institutions with maternal facilities and attending more than five thousand deliveries per year each one of them. Were studied incidence and clinical picture from neonatal C. trachomatis conjunctivitis. Positive immunofluorescent and conjunctive culture of secretion to C. trachomatis in the sample were 86 per cent (32 out of 37). 19 of the newborns acquired Staphylococcus associated to C. trachomatis (59%): nine with S. aureus in six Staphylococcus negative coagulase was isolated and four with the latest two. Out of 32 patients who demonstrated positive cultures to C. trachomatis (86%), 22(69%) were males and ten (31%) were females. Significant proportion of newborns were identified as small for gestational age. 18 of them were born by natural way and 14 by cesarean section. In 16/32 (50%) had interstitial pneumonia by Chlamydia. The main clinical findings were stated as: conjunctiva exudate in different stages including purulent secretion and oedema or inflammation of the ophthalmic conjunctiva. Those newborns where topical therapy did not irradiate the organism and demonstrated clinical picture persistence or relapse and diagnosis of C. trachomatis infection, systemic treatment with erythromycin and topic tetracycline were installed, disappearing all symptoms. Maternal history related to neonatal disease were mainly: endocervical infection, miscarriages and or preterm delivery.

[Antimicrobial activity of human colostrum against enteropathogens. Preliminary study]

The antimicrobial activity of the colostrum serum from ten women has been evaluated. The activity against Escherichia coli, Shigella sonnei and Klebsiella pneumonia at three different bacterial populations was determined (1 x 10(4), 1 x 10(5) and 1 x 10(6) UFC/ml). Antimicrobial activity against the three strains was found. Bactericidal activity was observed to inocula of 1 x 10(4) UFC/ml in 8/10 sera against E. coli, in 6/10 sera against S. sonnei, and in 3/10 sera against K. pneumonia; in the rest of the cases, sera were bacteriostatic. With inocula of 1 x 10(5) UFC/ml there was bactericidal activity in 4/10 sera against E. coli and S. sonnei and in 1/10 against K. pneumonia. Lastly, with inocula of 1 x 10(6) UFC/ml there was bactericidal activity in 4/10 sera against E. coli, 1/10 against S. sonnei and none against K. pneumoniae. The results suggest that because of the antimicrobial properties of human milk the risk of intestinal infections by enteropathogens is less.

[Systemic neonatal infection by Streptococcus pneumoniae. A case report]

The neonatal sepsis by Streptococcus pneumoniae is a clinical manifestation well know, but very often reported. It's role as an etiologic agent is limited to sporadic references in the medical literature, since 1972 only about fifty cases of septicaemia and/or meningitis have been reported. In the Instituto Nacional de Perinatología, from a whole of 560 confirmed cases of septicaemia in the newborn within the last 6 years, only one has been documented as systemic infections by S. pneumoniae. This was a 32.2 gestational aged male patient, with antecedent of maternal chorioamnionitis. This patient presented early-onset sepsis and died during the first 12 hours of life. Presence of S. pneumoniae was found in the blood culture. The type of clinical presentation and its correlation to the perinatal infection is discussed.

[Nosocomial infection in the neonatal period at a third level care center]

Results are presented on epidemiologic surveillance of nosocomial infection of all neonates attended at the Instituto Nacional de Perinatologia throughout 1988-1990, reporting rates of 2.1, 2.9 and 5.5 per 100 discharge for each of the years studied. Data are presented in full by service, showing rates of 4.7, 9.5 and 23.0 per 100 discharge in Neonatal Intensive Care Unit (NICU) and 1.5, 3.2 and 6.7 per 100 discharge for Neonatal Intermediate Care (NIC) for the same three years. With respect to type of infection, septicemia, pneumonia and conjunctivitis come as the most frequent causes of infection and Staphylococcus sp coagulase negative (30%), Staphylococcus aureus (27%) and Escherichia coli (7%) as the prevailing microorganisms in nosocomial infection.

[Perinatal transmission of AIDS. Experience at the National Institute of Perinatology]

From January 1989 to February 1992, 19 pregnant women infected with human immunodeficiency virus (HIV) were attended at the Instituto Nacional de Perinatologia in Mexico City, all of them at the end of pregnancy as well as 15 of their offspring. Sexual transmission was found in 15 patients; the initial classification of 16 was CDC II, only one case with AIDS, and during pregnancy 2 cases changed their clinical status. Absolute CD4 count in 2 cases was lower 20%, None of 10 had positive VDRL and one case showed a positive PPD. All neonates were at term and eutrophics. During their first 3 months of life, 2 had an infectious disease and died. The serologic follow-up at the moment reports 3 having HIV infection (20%), 3 no HIV infection and 9 in study are sero-positive.

Neonatal septicaemia due to K. pneumoniae. Septicaemia due to Klebsiella pneumoniae in newborn infants. Nosocomial outbreak in an intensive care unit

The authors report a nosocomial infection outbreak by Klebsiella pneumoniae, observed in neonates at a gyneco-obstetrical hospital from Mexico City. Forty six newborns presented one or more infections due to K. pneumoniae during their stay in neonatal care units, between October 3 and November 12, 1988. Sepsis was documented in 41 cases by clinical picture and routine laboratory exams, including one positive, blood culture at least. The most frequent invasive procedures practiced in these patients were catheterization and ventilatory support. K. pneumoniae was isolated as well from several environmental sources that could have led to infection of patients. Treatment of cases was initiated with ampicillin-amikacin, however, therapeutic failure with a lethality rate of 50% (14/28) and results of antimicrobial susceptibility conducted to treatment with cefotaxime. Fifteen out of 19 patients receiving the cephalosporin survived. To prevent outbreaks like the one presented here, we concluded that appropriate measures dealing with hygiene and education of personnel plus monitoring of bacterial susceptibility to antimicrobials, should prove successful in our environment.

[Blood concentrations of immunoglobulins in children with vitamin A deficiency]

The object of this study is to measure the influence that vitamin A has upon seric concentrations of different isotypes of immunoglobulins (IgM, IgG, IgA) in children with a normal nutritional state or a slightly subnormal one, as well as that of patients with lower respiratory infections. Fifty two children were studied over a period of 24 months. Twenty eight of these were from an orphanage, while 24 were hospitalized, due to a low respiratory infection. The patients with lower respiratory infection showed normal average concentration of vitamin A, but under that of the orphanage (p less than 0.025). It was also observed that malnutrition influences the seric concentrations of immunoglobulins, which were higher in normal individuals; never the less, when this group show deficiency of vitamin A the serum concentration of IgM became lower in the orphanage, malnutrition children. In a similar way, a lowering of IgG was observed in patients with lower respiratory infections and vitamin A deficiency, while no alterations were found in the serum concentration of IgG in any of the groups studied with vitamin deficiency. It is concluded that the concentrations of vitamin A and the nutritional state modify serum values of IgM and IgG.

[Streptococcus group B in the etiology of neonatal infection]

Group B Streptococcus (GBS) causes maternal infections during perinatal period and serious neonatal infections. Their frequency in our country is still unknown. This study analyzed the clinical and epidemiological characteristics of 13 neonates inborn at the Instituto Nacional de Perinatología with early or late onset group B streptococcal infection. The incidence of early onset diseases (EOGBS) was 0.7 cases/1,000 live births among 20,054 inborn, and 1 case/20,000 live births of late onset diseases. EOGBS was more common in preterm newborn (median 33.2 w), low birth weight (median 2.025 g) with several maternal risk factors. Lethality rate was 38.5% (5/13). GBS is a recent important pathogen in our institute that must be investigated in another institution of our country. Group B Streptococcus; neonatal septicemia; neonatal pneumonia.

[Neonatal systemic infection caused by Listeria monocytogenes]

Listeria monocytogenes is a gram positive cocco-bacillus which causes perinatal infections and also attacks immunocompromised hosts. Little is known about it in our medium. As part of a prospective study on neonatal systemic infections, its participation at the National Institute of Perinatology was researched. During a period of 18 months, 9,283 live newborns were observed, 141 of them were diagnosed with neonatal septicemia. During this period seven neonates had systemic infections due to Listeria monocytogenes: three had septicemia (two of these with meningitis) and all seven cases had pneumonia. The gestational age of the neonates was 26.1 to 41 weeks (X + DS = 35 + 4.3), with a weight of 830 g to 2,975 g (X + DS 1,958 + 773), four out of seven weighed less than 2,000 grams. The most frequent clinical manifestation was respiratory related causing a need for a differential diagnosis with hyaline membrane disease, transitory tachypnea and meconium swallowing at birth. All of the strains isolated were found to be susceptible to ampicillin, penicillin, gentamicin and amikacin; requiring high CMI levels of cephalosporins.