LA CONSULTA SEMANAL

JULIO 2000

CONSULTA

Acta Paediatr Suppl 1999 Dec;88(432):36-9 
Control of congenital infection with Toxoplasma gondii by neonatal screening based on detection of specific immunoglobulin M antibodies eluted from phenylketonuria filter-paper blood-spot samples. 
Petersen E, Eaton RB 
Laboratory of Parasitology, Statens Serum Institut, Copenhagen, Denmark. 
Two ongoing neonatal screening programmes for congenital infection with Toxoplasma gondii are presented. The New England Newborn Screening Programme has included congenital toxoplasmosis since 1986. The test is based on detection of Toxoplasma-specific immunoglobulin M (IgM) antibodies eluted from the phenylketonuria (PKU) card. The seroprevalence of Toxoplasma IgG antibodies is at present about 13% and the birth prevalence of congenital toxoplasmosis approximately 1 per 10000 liveborn children. The Danish national neonatal screening programme was expanded to include congenital
toxoplasmosis from 1 January 1999. The test is also based on detection of Toxoplasma-specific IgM antibodies eluted from PKU cards. The seroprevalence of Toxoplasma IgG antibodies in pregnant women is around 25% and the birth prevalence about 1 per 3000 liveborn children. The birth prevalence of congenital Toxoplasma infection is within the range of other congenital disorders included in different screening programmes. Neonatal screening is feasible in areas with a low risk of congenital infection where prenatal screening will not be applicable. 
Publication Types: 
· Review 
· Review, tutorial 

BMJ 1999 Jun 5;318(7197):1511-4 [Texto completo] 
Congenital toxoplasmosis: systematic review of evidence of efficacy of treatment in pregnancy. 
Wallon M, Liou C, Garner P, Peyron F 
Service de Parasitologie, Hopital de la Croix-Rousse, 69004 Lyons, France. wallon@rockefeller.univ-lyon1.fr 
OBJECTIVE: To summarise the evidence that treating toxoplasmosis in pregnancy reduces the risk of congenital toxoplasma infection and improves infant outcomes. DESIGN: Systematic review of studies comparing at least two concurrent groups of pregnant women with proved or likely acute toxoplasma infection in which treatments were compared with no treatment and outcomes in the children were reported. SUBJECTS: Studies were identified from Medline (1966-97), Pascal (1990-7), Embase (1993-7), and Biological abstracts (1993-5) plus contact with experts in the field, including the European Research Network on Congenital Toxoplasmosis. Main outcome measure: Proportion of infected children at 1 year born to infected pregnant women who were or were not treated. RESULTS: Out of 2591 papers identified, nine met the inclusion criteria. There were no randomised comparisons, and control groups were generally not directly comparable with the treatment groups. Congenital infection was common in treated groups. five studies showed that treatment was effective and four that it was not. CONCLUSION: It is unclear whether antenatal treatment in women with presumed toxoplasmosis reduces congenital transmission of Toxoplasma gondii. Screening is expensive, so the effects of treatment and impact of screening programmes need to be evaluated. In countries where screening or treatment is not routine, these technologies should not be introduced outside carefully controlled trials. 
Publication Types: 
· Meta-analysis 

Presse Med 1999 Apr 10;28(14):753-7 
[Problems of congenital toxoplasmosis. Evolution over four decades]. 
Couvreur J 
Laboratoire de la Toxoplasmose, Institut de Puericulture, Paris. 
EFFECT OF PREVENTIVE MEASURES: The development of reliable routine serology tests and the demonstration of the high prevalence of toxoplasmosis in France led to mandatory prospective screening of pregnant women in 1978, followed by prenatal screening in 1985. In addition, in utero diagnosis, first on fetal blood and now with the reliable and safe method using polymerase chain reaction on amniotic fluid, formally identifies the parasite. THE SITUATION TODAY: A comparison of the experience of a specialized center in Paris during three different periods over the last 40 years showed that currently 71% of all cases of congenital toxoplasmosis are infraclinical at birth and only 5% are severe. Mean incidence of seroconversion during pregnancy is 1.48%, with a 40% risk of fetal contamination if no treatment is given. The risk of overt fetopathy predominantly concerns maternal infections occurring prior to 26 weeks gestation. IN UTERO TREATMENT: Positive PCR diagnosis on amniotic fluid imposes serial ultrasound examinations to identify any fetopathy and an in utero treatment by giving the mother the pyrimethamine-sulfadiazine combination. Biological results are favorable. POST-NATAL TREATMENT 
Post-natal treatment is indicated even in latent forms and should be continued for the first year of life. The
pyrimethamine-sulfadiazine combination is the only pharmaceutical regimen with well-proven efficacy. New compounds should allow better prophylaxis against maternofetal contamination or improved post-natal treatment. RECURRENCE: In 70% of the cases, serology tests become positive again, but are not associated with significantly increased risk of ocular recurrence. 
Publication Types: 
· Historical article 
· Review 
· Review of reported cases 
Comments: 
· Comment in: Presse Med 1999 Oct 2;28(29):1579 

Arch Gynecol Obstet 1995;256 Suppl:S170-2 
[-Screening for toxoplasmosis in pregnancy-]. 
Extermann P 
Departement de Gynecologie et d'Obstetrique, Hopital Cantonal Universitaire, Geneve, Switzerland. 
Publication Types: 
· Review 
· Review, tutorial 

Arch Gynecol Obstet 1995;256 Suppl:S165-9 
[-Toxoplasmosis in pregnancy: arguments in favor of systematic screening in Switzerland-]. 
Hohlfeld P 
Departement de Gynecologie et Obstetrique, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. 
Publication Types: 
· Review 
· Review, tutorial 

Clin Infect Dis 1994 Jun;18(6):853-61; quiz 862 
Toxoplasmosis in pregnancy. 
Wong SY, Remington JS 
Department of Immunology and Infectious Diseases, Research Institute, Palo Alto Medical Foundation, California. 
Publication Types: 
· Review 
· Review literature 
Comments: 
· Comment in: Clin Infect Dis 1995 Mar;20(3):727-9 

Am Fam Physician 1992 Apr;45(4):1683-90 
Toxoplasmosis in pregnancy: an emerging concern for family physicians. 
Bakht FR, Gentry LO 
Department of Family Medicine, Baylor College of Medicine, Houston, Texas. 
Toxoplasmosis is usually asymptomatic in pregnant women but poses a risk of severe effects on the fetus. One to eight of every 1,000 pregnant women become infected, and the infection is transmitted to the fetus in approximately 40 percent of these cases. The risk of transmission rises with increasing gestational age at the time of initial infection. Congenital infection with toxoplasmosis may lead to serious sequelae, such as blindness, mental retardation, neurologic deficits and deafness. Prevention of morbidity from toxoplasmosis depends on prevention of the infection in pregnant women, plus early recognition and aggressive treatment of maternal infections. 
Publication Types: 
· Review 
· Review, tutorial