Enfoque terapéutico profiláctico para reducir la morbilidad por paludismo en la mujer embarazada / Prophylactic therapeutic approach to reduce malaria morbidity among pregnant women

Introducción: La infección por malaria durante el embarazo es un importante problema de salud en la mayoría de las regiones tropicales. Esta condición puede tener incidencia negativa tanto en la gestante como en el feto. Objetivo: Indagar en el impacto del tratamento preventivo intermitente con el medicamento antimalárico sulfadoxina-pirimetamina en la mujer embarazada. Métodos: Se realizó una revisión bibliográfica en la base de datos Medline/Pub Med y en artículos relevantes relacionados al tema de los últimos cinco años. Además, se tomó como referencia las guías para el tratamiento de malaria de la Organización Mundial de la Salud, verisón 2016-2017. Análisis y síntesis de los resultados: Durante el período 2015-2017 no se lograron avances significativos en la reducción del número de enfermos palúdicos. No obstante, se señala la anemia como causa de mortalidad en el curso de la malaria. También, se destacan los nuevos enfoques y compromisos para reducir la morbilidad atribuible al paludismo en la mujer embarazada en sus tres vertientes: tratamiento eficaz de los casos de paludismo, el uso de mosquiteros tratados con insecticidas, y la utilización del tratamiento preventivo intermitente con el antimalárico sulfadoxina-pirimetamina a partir del segundo trimestre del embarazo. La indicación de este tratamiento inlcuye mínimo dos dosis del fármaco antipalúdico, con un intervalo de un mes entre cada dosis, con independencia de que las embarazadas muestren o no síntomas de la enfermedad. Conclusiones: Esta intervención para prevenir el paludismo en el embarazo es una cuestión prioritaria en la iniciativa de salud materna, infantil y reproductiva; además, ayuda a mejorar y aumentar la cobertura de las medidas de control de esta enfermedad durante la gestación(AU)

Introduction: Malaria infection during pregnancy is an important health problem in most tropical regions. This condition may have a negative incidence on pregnant women and fetuses. Objective: Inquire into the effect of the intermittent preventive treatment with the malarial sulfadoxine / pyrimethamine in pregnant women. Methods: A bibliographic review was conducted in the database Medline / PubMed and in relevant papers about the topic published in the last five years. The Guidelines for the Treatment of Malaria 2016-2017 of the World Health Organization were also used as reference. Analysis and synthesis of results: Significant progress was not achieved in reducing the number of malaria patients in the period 2015-2017. However, anemia is reported as the cause of mortality during the course of malaria. New approaches and commitments are proposed to reduce malaria-related morbidity among pregnant women, namely effective treatment of malaria cases, use of insecticide-treated mosquito nets, and intermittent preventive treatment with the antimalarial sulfadoxine / pyrimethamine as of the second quarter of pregnancy. Indication of this treatment includes at least two doses of the malarial, with a separation of one month between the doses, regardless of whether the pregnant women have symptoms of the disease. Conclusions: The intervention to prevent malaria during pregnancy is a first-priority aspect of the mother, child, reproductive health initiative. It also helps improve and broaden the coverage of measures for the control of this disease during pregnancy(AU)

Molecular variation of Plasmodium vivax dehydrofolate reductase in Mexico and Nicaragua contrasts with that occurring in South America / Variación molecular de la dehidrofolato reductasa de Plasmodium vivax en México y Nicaragua contrasta con la que ocurre en Sudamérica

Abstract: Objective: To research mutations associated to pyrimethamine resistance in dihydrofolate reductase (pvdhfr) of Plasmodium vivax from Mexico and Nicaragua and compare it to that reported in the rest of America. Materials and methods: Genomic DNA was obtained from P. vivax-infected blood samples. A pvdhfr gene fragment was amplified and sequenced. The identified gene variations were compared to those observed in other affected sites of America. Results: No mutations in pvdhfr were detected in P. vivax from Mexico and Nicaragua. One synonymous change and variation in the repeat domain was detected in Nicaraguan parasites. In South America, a high frequency of variant residues 58R and 117N associated to pyrimethamine resistance was reported. Conclusions: The lack of polymorphisms associated with pyrimethamine resistance suggests that drug-resistant P. vivax has not penetrated Mesoamerica, nor have local parasites been under selective pressure. These data contribute to establish the basis for the epidemiological surveillance of drug resistance.

Resumen: Objetivo: Determinar mutaciones en la dihydrofolato reductasa deP. vivax (Pvdhfr) en parásitos de México y Nicaragua, y comparar con lo reportado en América. Material y métodos: Del ADN de sangres infectadas con P. vivax de pacientes, el gen pvdhfr se amplifico y secuenció, y se contrastócon lo observado en América. Resultados: No se detectaron mutaciones asociadas con la resistencia debida a pirimetamina. Los parásitos de Nicaragua tuvieron una mutación sinónima y variación en la región repetida. Se reportaron frecuentes mutaciones asociadas con la resistencia a la pirimetamina en Sudamérica. Conclusiones: La ausencia de polimorfismos en Pvdhfr sugiere que no se han seleccionado ni introducido parásitos resistentes en la zona de estudio, lo que resulta muy útil para la vigilancia epidemiológica.

Condução da toxoplasmose gestacional / Management of gestational toxoplasmosis

A toxoplasmose é uma doença proveniente do Toxoplasma gondii, um protozoário que tem os felinos como seu hospedeiro definitivo e os mamíferos e aves como seu hospedeiro intermediário. Tem um curso benigno e autolimitado quando acomete um indivíduo imunocompetente, no entanto a infecção durante a gestação acarreta até 50% de chance de toxoplasmose congênita, podendo causar danos severos ao feto. A virulência dos genótipos encontrados nas Américas Central e do Sul é a mais alta, comparada a Europa e América do Norte, tendo a doença um comportamento mais agressivo. Os estudos relatam a diminuição da infecção fetal em até 60% com o uso da espiramicina, usada ainda na profilaxia. Este artigo discute sobre a triagem materna pré-natal e sua necessidade, a profilaxia e o tratamento da infecção fetal ainda intraútero, com o objetivo de diminuir a transmissão vertical e as sequelas neonatais com suas implicações ao longo da vida.(AU)

Toxoplasmosis it is a disease originating from Toxoplasma gondii, a protozoan that has felines at as ultimate host and mammals and birds at as intermediate host. Has a benign and self-limiting course when affects immunocompetent individual, however, infection during pregnancy leads 50% chance of congenital toxoplasmosis and can cause severe damage to the fetus. The virulence of genotypes found in Central and South America is the highest compared to Europe and North America, having the disease a more aggressive behavior. Studies report a reduction in fetal infection 60% with the use spiramycin still used for prophylaxis. This article discusses prenatal maternal screening, prophylaxis and treatment of fetal infection still in utero with the objective of decreasing vertical transmission and neonatal sequelae with their lifelong implications.(AU)

Toxoplasmosis congénita, una mirada en la actualidad del tratamiento; revisión de la literatura / Congenital toxoplasmosis, a look at contemporary treatment; literature review / Toxoplasmose congênita, um olhar atual no tratamento; revisão de literatura

Introducción. La Toxoplasmosis congénita constituye una causa significativa de morbi-mortalidad neonatal en países de bajos ingresos como Colombia. Puede originar prematuridad, secuelas patológicas y pérdida fetal. El tamizaje en las gestantes y, a su vez, un tratamiento oportuno y adecuado disminuye la transmisión vertical y sus nefastas secuelas. El objetivo es presentar evidencia científica actualizada sobre el tratamiento farmacológico de la Toxoplasmosis Congénita. Metodología. Se realizó una búsqueda no sistemática en bases de datos: Pubmed, Medline, Clinical Key y Springer. Se incluyeron artículos originales y de revisión de tema publicados desde enero de 2014 hasta abril de 2019. División de los temas tratados. se abordan la fisiopatología y clínica, el abordaje diagnóstico, alternativas de prevención y tratamiento. Conclusiones. En la actualidad la terapia farmacológica es limitada, los esquemas de manejos se basan en espiramicina o la combinación de sulfadiazina/pirimetamina y ácido folínico; estas moléculas no son del todo bien toleradas y presentan un amplio espectro de reacciones adversas secundario a sus efectos tóxicos; resulta necesario la ejecución de estudios aleatorizados para evaluar su efectividad. Cómo citar: Rueda-Paez YS, Valbuena-Ruiz L, Quintero-Pimiento N, Pinilla-Plata A, Sayago-Silva J. Toxoplasmosis congénita, una mirada en la actualidad del tratamiento; revisión de la literatura. MedUNAB. 2019;22(1):51-63. doi: 10.29375/01237047.2612

Introduction. Congenital Toxoplasmosis constitutes a significant cause of neonatal morbimortality in underdeveloped countries like Colombia. It can cause prematurity, pathological after-effects and fetal loss. Screening expectant mothers and in turn, a timely and adequate treatment, reduce vertical transmission and its devastating effects. The objective is to present up-to-date scientific evidence about the pharmacological treatment of Congenital Toxoplasmosis. Methodology. A non-systematic search of databases was conducted: Pubmed, Medline, Clinical Key and Springer. Original and topic review articles were included dating from January 2014 to April 2019. Division of topics covered. Physiopathology and clinical pathology, diagnostic approach, prevention and treatment alternatives were addressed. Conclusions. At this time, pharmacological therapy is limited, management schemes are based on spiramycin or a combination of sulfadiazine/pyrimethamine and folinic acid; these molecules are not very well tolerated and exhibit a wide spectrum of adverse reactions apart from their toxic effects, thus it is necessary to conduct randomized studies to evaluate its effectiveness. Cómo citar: Rueda-Paez YS, Valbuena-Ruiz L, Quintero-Pimiento N, Pinilla-Plata A, Sayago-Silva J. Toxoplasmosis congénita, una mirada en la actualidad del tratamiento; revisión de la literatura. MedUNAB. 2019;22(1):51-63. doi: 10.29375/01237047.2612

Introdução. A toxoplasmose congênita é uma causa significativa de morbidade e mortalidade neonatal em países de baixa renda, como a Colômbia. Pode causar prematuridade, sequelas patológicas e perda fetal. A triagem em gestantes e, por sua vez, um tratamento oportuno e adequado diminui a transmissão vertical e suas consequências desastrosas. O objetivo é apresentar evidências científicas atualizadas sobre o tratamento farmacológico da Toxoplasmose Congênita. Metodologia. Foi realizada uma revisão não sistemática nas bases de dados: Pubmed, Medline, Clinical Key e Springer. Foram incluídos tanto artigos originais, quanto revisões de tópicos publicados de janeiro de 2014 até abril de 2019. Divisão dos tópicos discutidos. foram abordadas a fisiopatologia e a clínica, a abordagem diagnóstica, alternativas para prevenção e tratamento. Conclusões. Atualmente, a terapia farmacológica é limitada, os esquemas terapéuticos baseiam-se na espiramicina ou na combinação de sulfadiazina/pirimetamina e ácido folínico; estas moléculas não são totalmente toleradas e apresentam um amplo espectro de reações adversas secundárias aos seus efeitos tóxicos. É necessário realizar estudos randomizados para avaliar sua eficácia. Cómo citar: Rueda-Paez YS, Valbuena-Ruiz L, Quintero-Pimiento N, Pinilla-Plata A, Sayago-Silva J. Toxoplasmosis congénita, una mirada en la actualidad del tratamiento; revisión de la literatura. MedUNAB. 2019;22(1):51-63. doi: 10.29375/01237047.2612

Toxoplasmosis ocular. Descripción de tres pacientes con presentación atípica / Ocular toxoplasmosis. Description of three patients with an atypical presentation.

Objetivo: Describir una forma de presentación atípica de toxoplasmosis ocular, enfatizando la importancia de la jerarquización de los hallazgos clínicos y las limitaciones de la serología para realizar un diagnóstico temprano. Pacientes y Métodos: Estudio retrospectivo y descriptivo de tres casos clínicos de toxoplasmosis ocular activa, con presentación atípica (compromiso del nervio óptico), derivados al Servicio de Oftalmología del Hospital J. P. Garrahan en el periodo comprendido entre 2007 y 2010. Resultados: En los tres casos presentados la sospecha clínica de toxoplasmosis ocular no se correlacionó con evidencia serológica de infección reciente. En un caso, la terapéutica específica temprana, basada en la sospecha clínica, resultó en una excelente recuperación funcional. Un tratamiento tardío puede interferir en el resultado visual. Conclusiones: Basados en los hallazgos clínicos y la alta sospecha de esta patología debe iniciarse el tratamiento específico sin esperar que los resultados serológicos la confirmen. Eventualmente, la mejoría clínica confirmara el diagnóstico. El comportamiento de los títulos de anticuerpos en el curso de la enfermedad ocular no siempre es confiable, y en muchos casos retrasa el comienzo de la terapéutica con la consiguiente mala rehabilitación visual de estos pacientes (AU)

Objective: To describe an atypical presentation of ocular toxoplasmosis, emphasizing the importance of clinical findings and the limitations of serology in the early diagnosis. Patients and Methods: A retrospective, descriptive study was conducted of three cases with active ocular toxoplasmosis with an atypical presentation (optic nerve involvement), referred to the Department of Ophthalmology of Hospital J. P. Garrahan between 2007 and 2010. Results: In the three cases presented here clinical suspicion of ocular toxoplasmosis did not correlate with serological evidence of a recent infection. In one case, early treatment, based on clinical suspicion, resulted in excellent functional recovery. Late management may compromise visual outcome. Conclusions: Based on clinical findings and suspicion of the pathology, specific treatment should be started without waiting for serological confirmation. Eventually, clinical improvement will confirm the diagnosis. The behavior of antibody titres in the course of the ocular disease is not always reliable and often delays treatment initiation with subsequent difficulties in the visual rehabilitation of these patients (AU)

Alelos mutantes asociados a la resistencia a cloroquina y sulfadoxina-pirimetamina en Plasmodium falciparum de las fronteras Ecuador-Perú y Ecuador-Colombia / Mutant alleles associated to chloroquine and sulfadoxine-pyrimethanime resistance in Plasmodium falciparum of the Ecuador-Peru and Ecuador-Colombia borders

Se evaluó la frecuencia de mutaciones en los genes pfCRT y DHFR/DHPS del Plasmodium falciparum asociados a la resistencia a cloroquina y sulfadoxina-pirimetamina en 83 cepas provenientes de los distritos Esmeralda y Machala ubicados en las fronteras entre Ecuador-Perú y Ecuador-Colombia durante el año 2002. Se empleó la reacción en cadena de polimerasa (PCR) convencional y sus variantes. El gen pfCRT presentó más de 90% de muestras mutantes en Esmeralda y Machala. Para el gen DHFR, el 90% de las cepas fueron muestras mutantes en Esmeralda, tres fueron mutaciones dobles y una triple; en Machala se encontró 25% de formas mutantes simples y 75% de formas mixtas (formas silvestres/mutantes). En conclusión, la resistencia a cloroquina se ha fijado en las cepas portadoras de la mutación K76T pfCRT, mientras que la impronta genética a la resistencia a pirimetamina está en evolución, principalmente en el distrito de Esmeralda.

The frequency of mutations in pfCRT and DHFR/DHPS genes of Plasmodium falciparum associated with resistance to chloroquine and sulfadoxine-pyrimethamine was evaluated in 83 strains from the districts of Esmeralda and Machala, located on the borders of Ecuador-Peru and Ecuador-Colombia in 2002. Polymerase chain reaction (PCR), conventional and its variants, was used. Mutations in the pfCRT gene were found in more than 90% of the samples from Esmeralda and Machala. For the DHFR gene, 90% of the strains were mutant samples from Esmeralda, 3 were double mutations and 1 was a triple mutation. In Machala, 25% were simple mutant forms and 75% mixed mutant forms (wild forms/mutant). In conclusion, resistance to chloroquine has been fixed in strains carrying K76T pfCRT mutation, whereas genetic imprinting for resistance to pyrimethamine is evolving, particularly in the district of Esmeralda.

Estudio retrospectivo de la aplicación de la amplificación génica cualitativa en muestras biológicas para el seguimiento de la toxoplasmosis en pacientes pediátricos receptores de trasplante de células progenitoras hematopoyéticas / Retrospective study of the implementation of the qualitative PCR technique in biological samples for monitoring toxoplasmosis in pediatric patients receiving hematopoietic stem cell transplantion

La toxoplasmosis es una infección oportunista causada por el parásito Toxoplasma gondii; su infección es grave y de difícil diagnóstico en pacientes que reciben un trasplante alogénico de células progenitoras hematopoyéticas (TCPH). En el Hospital de Pediatría S.A.M.I.C. "Profesor Dr. Juan P. Garrahan" se realizó la vigilancia postrasplante de 12 pacientes receptores de TCPH mediante la técnica de PCR cualitativa. La necesidad de seguimiento de estos pacientes fue definida por el antecedente de serología positiva para toxoplasmosis en el donante o receptor y ante la imposibilidad de iniciar el uso profiláctico de trimetoprima-sulfametoxazol a causa de la condición hematológica. Dos pacientes presentaron signos de enfermedad por T. gondii con resultado de PCR positivo y recibieron tratamiento con pirimetamina-clindamicina. En otros dos, la toxoplasmosis fue causa de muerte y hallazgo de autopsia, con resultado de PCR negativo. Cuatro pacientes recibieron tratamiento contra toxoplasmosis por la detección de una PCR positiva, sin manifestaciones clínicas. En los cuatro pacientes restantes no se detectaron signos de enfermedad por toxoplasmosis, con resultados de PCR negativos durante el seguimiento. La técnica de PCR cualitativa demostró ser útil para detectar la reactivación de la toxoplasmosis en receptores de TCPH, pero tiene limitaciones para el seguimiento y la toma de decisiones clínicas en pacientes con PCR positiva que persiste en el tiempo y manifestaciones de toxicidad por el tratamiento.

Toxoplasmosis is an opportunistic infection caused by the parasite Toxoplasma gondii. The infection is severe and difficult to diagnose in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT). Twelve patients receiving HSCT were monitored post-transplant, by qualitative PCR at the Children's Hospital S.A.M.I.C. "Prof. Dr. Juan P. Garrahan". The monitoring of these patients was defined by a history of positive serology for toxoplasmosis in the donor or recipient and because their hematologic condition did not allow the use of trimethoprim-sulfamethoxazole for prophylaxis. During the patients' monitoring, two of them with positive PCR results showed signs of illness by T. gondii and were treated with pyrimethamine-clindamycin. In two other patients, toxoplasmosis was the cause of death and an autopsy finding, showing negative PCR results. Four patients without clinical manifestations received treatment for toxoplasmosis because of positive PCR detection. In four patients there were no signs of toxoplasmosis disease and negative PCR results during follow-up. The qualitative PCR technique proved useful for the detection of toxoplasmosis reactivation in HSCT recipients, but has limitations in monitoring and making clinical decisions due to the persistence of positive PCR over time and manifestations of toxicity caused by the treatment.

The in vivo antimalarial activity of methylene blue combined with pyrimethamine, chloroquine and quinine

The effectiveness of methylene blue (MB) combined with pyrimethamine (PYR), chloroquine (CQ) or quinine (Q) was examined in a classical four-day suppressive test against a causative agent of rodent malaria, Plasmodium berghei. A marked potentiation was observed when MB was administered at a non-curative dose of 15 mg/kg/day in combination with PYR (0.19 mg/kg/day) or Q (25 mg/kg/day). No synergy was found between MB (15 mg/Kg) and CQ (0.75 mg/Kg). Our results suggest that the combination of MB with PYR or Q may improve the efficacy of these currently used antimalarial drugs.

Plasmodium falciparum infection in pregnant women attending antenatal care in Luanda, Angola / Infecção por Plasmodium falciparum em mulheres grávidas em consultas pré-natal em Luanda, Angola

INTRODUCTION: Malaria during pregnancy remains a serious public health problem. The aim of this study was to establish the prevalence and possible risk factors for malaria in pregnant women attending antenatal care at Augusto Ngangula Specialized General Hospital in Luanda, Angola. METHODS: Pregnant women (679 total) who attended antenatal care from April to September 2008 were included in the study after signing informed consent. For each participant, the social-demographic profile and malaria and obstetric histories were investigated via a questionnaire. Diagnosis was made by optic microscopy, and hemoglobin concentration measured. The associations between age, parity, gestational age, residence, schooling, malaria during gravity, anemia and treatment with incidence of Plasmodium falciparum infection were analyzed through logistic regression. RESULTS: During the period of study, 74 (10.9%) out of 679 women were infected by P. falciparum. The average concentration of hemoglobin was 11.1 ± 0.07g/dL, and there were significant associations between the history of malaria during pregnancy, P. falciparum infection (p<0.01) and anemia at the time of observation (p<0.001). CONCLUSIONS: Previous history of malaria during pregnancy represents a risk factor for current infection and anemia was an important complication associated with malaria, even in women who were treated with sulfadoxine-pyrimethamine during pregnancy.

INTRODUÇÃO: A malária na gravidez continua a ser um grave problema de saúde pública. O objetivo deste estudo foi determinar a prevalência e possíveis fatores de risco para a malária, em mulheres grávidas que foram atendidas em consultas pré-natal, no Hospital Geral Especializado Augusto Ngangula, em Luanda, Angola. MÉTODOS: De abril a setembro de 2008, 679 mulheres grávidas foram envolvidas no estudo após consentimento informado. O perfil sócio demográfico e história de malária e obstetrícia foram investigados através de um questionário. O diagnóstico foi efetuado por microscopia óptica e determinou-se ainda as concentrações da hemoglobina. Através da regressão logística foi analisada a associação entre a idade, paridade, tempo de gestação, residência, escolaridade, malária durante a gravidez, anemia e tratamento com a infecção por Plasmodium falciparum. RESULTADOS: Setenta e quatro (10,9%) das 679 mulheres estavam infectadas com P. falciparum. O valor médio da concentração da hemoglobina foi de 11,1 ± 0,07g/dL, encontrando-se uma associação significativa entre história de malária na gravidez e infecção por P. falciparum (p<0,01) e anemia no momento da observação (p<0.001). CONCLUSÕES: A história de malária anterior na gravidez foi um fator de risco para uma infecção atual e a anemia uma complicação importante associada à malária, mesmo em mulheres que receberam tratamento durante a gravidez com sulfadoxina-pirimetamina.

Nephrotic syndrome associated with toxoplasmosis: report of seven cases / Síndrome nefrótica associada à toxoplasmose: relato de sete casos

The concomitance of nephrotic syndrome and acute infection by Toxoplasma gondii is a rare occurrence in humans. In this paper seven cases of children, ranging from 11 months to 7 year-old, with concomitant nephrotic syndrome and asymptomatic acute T. gondii infection are reported. In one of those patients only the administration of anti-Toxoplasma therapy was enough to control the clinical and laboratory manifestations of the disease. In the other patients it was necessary to introduce corticosteroids or other immunosuppressant drugs. Three patients had complete clinical and laboratory improvement and the remaining showed only a partial response.

Ocorrência concomitante de síndrome nefrótica e infecção aguda por Toxoplasma gondii em seres humanos é situação pouco frequente. No presente trabalho são relatados sete casos de crianças, com idade variável entre 11 meses e sete anos, que apresentavam síndrome nefrótica e infecção aguda por T. gondii assintomática. Em um dos pacientes o tratamento específico anti-Toxoplasma foi suficiente para controlar clínica e laboratorialmente as manifestações da doença. Nos demais foi preciso administrar corticosteróides ou outras drogas imunossupressoras. Após introdução desse esquema três pacientes apresentaram remissão completa dos sintomas; os demais apenas remissão parcial.

Disseminated toxoplasmosis in an immunocompetent patient from Peruvian Amazon / Toxoplasmosis diseminada en un paciente inmunocompetente procedente de la Amazonía peruana

We report a case of severe toxoplasmosis in an immunocompetent patient, characterized by pneumonia, retinochoroiditis, hepatitis and myositis. Diagnosis was confirmed by serology, T. gondii in thick blood smear and presence of bradyzoites in muscle biopsy. Treatment with pyrimethamine plus sulfadoxine was successful but visual acuity and hip extension were partially recovered. This is the first case report of severe toxoplasmosis in an immunocompetent patient from Peru.

Reportamos un caso de toxoplasmosis severa en un paciente inmunocompetente caracterizado por neumonía, retinocoroiditis, hepatitis y miositis. El diagnóstico fue confirmado por serología, el hallazgo de T. gondii en gota gruesa y la presencia de bradizoitos en biopsia muscular. El tratamiento con pirimetamina mas sulfadoxina fue exitoso pero solo hubo una parcial recuperación de la agudeza visual y de la capacidad de extensión de la cadera. Este es el primer reporte de un caso de toxoplasmosis severa en el Perú.

Caracterización clínica y radiológica del compromiso pulmonar por toxoplasmosis aguda diseminada en nueve pacientes inmunocompetentes / Clinical and radiological characterization of the pulmonary commitment for acute toxoplasmosis disseminated in nine immunocompetents patients

La toxoplasmosis aguda en el individuo inmunocompetente generalmente tiene un comportamiento benigno y autolimitado. Sin embargo, en pacientes provenientes de área selvática se han presentado casos severos de compromiso visceral, el más frecuente de ellos, el pulmonar. Se realizó la descripción clínica y radiológica de nueve individuos miembros de las fuerzas militares de Colombia, con toxoplasmosis aguda y compromiso pulmonar. El 55% de los casos presentó disnea clase funcional II/IV; 33% clase funcional III/IV y tan sólo 1/9 pacientes presentó clase funcional IV/IV. La imagen radiológica más común fue la consolidación pulmonar unifocal o multifocal (66%), y en menor frecuencia la presencia de infiltrados reticulares, reticulonodulares y derrame pleural. La totalidad de los pacientes evolucionaron en forma satisfactoria, dos de ellos con necesidad de soporte con ventilación mecánica no invasiva.

Mutaciones puntuales en los genes dhfr y dhps de Plasmodium falciparum de tres regiones endémicas para malaria en Colombia / Point mutations in dihydrofolate reductase and dihydropteroate synthase genes of Plasmodium falciparum from three endemic malaria regions in Colombia

Introducción. La acumulación progresiva de mutaciones en los genes dhfr y dhps lleva al parásito Plasmodium falciparum a evadir la acción de la sulfadoxina-pirimetamina, situación que aumenta el nivel de resistencia del parásito a estos medicamentos y conlleva a la aparición de fallas del tratamiento. Objetivos. Determinar la frecuencia de mutaciones en los genes dhfr y dhps de P. falciparum asociadas con resistencia a sulfadoxina-pirimetamina, en muestras de pacientes de tres zonas endémicas de Colombia: La Carpa, Guaviare; Casuarito, Vichada; Tierralta y Puerto Libertador, Córdoba. Materiales y métodos. Se incluyeron 40 muestras de pacientes con malaria no complicada por P. falciparum. Los alelos 108, 59 y 164 del gen dhfr se analizaron mediante PCR específica de alelo y los alelos 51 del gen dhfr y 436, 437 y 540 del gen dhps por PCR y restricción enzimática. Resultados. En el gen dhfr encontramos en todas las muestras las mutaciones asparagina 108 e isoleucina 51. No se detectaron alelos mutantes en los codones 59 y 164 del gen dhfr, ni en el codón 436 del gen dhps. La mutación glicina 437 estuvo presente en 36 muestras y el alelo silvestre alanina en tres de Tierralta y una de La Carpa. La mutación ácido glutámico 540 sólo se halló en Casuarito. Conclusiones. En las poblaciones de P. falciparum analizadas prevalecen los alelos asparagina 108, isoleucina 51 y glicina 437, lo que indica un efecto acumulativo de mutaciones y la necesidad de vigilar la aparición de nuevos alelos mutantes que puedan conducir a la pérdida total de la eficacia de la sulfadoxina-pirimetamina.

Introduction. Plasmodium falciparum has the ability to counter the antiparasitic activity of sulphadoxine-pyrimethamine by progressively accumulating mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes. These mutations gradually increase the resistance of the parasite to these drugs and lead to therapeutic failure. Objectives. To determine the frequency of mutations associated with resistance to sulphadoxine and pyrimethamine in the dhfr and dhps genes of P. falciparum in samples from patients in three endemic zones of Colombia -La Carpa, Guaviare; Casuarito, Vichada; and Tierralta and Puerto Libertador, Córdoba. Materials and methods. Forty samples were selected from patients with uncomplicated P. falciparum malaria. The frequency profiles of the 108, 59 and 164 alleles of dhfr were obtained by application of an allele-specific polymerase chain reaction, whereas the other alleles (alleles 51 of the dhfr gene and 436, 437 and 540 of dhps) were obtained by polymerase chain reaction and restriction fragment length polymorphism. Results. The 108N and 51I mutations in the dhfr gene were found in all of the 40 samples. No mutant alleles were found in the 59 and 164 codons of the dhfr gene, or in the 436 codon of the dhps gene. The 437G mutation was observed in 36 samples and the wild-type allele was present in 3 from Tierralta and one from La Carpa. The 540E mutation was only detected in two samples from Casuarito. Conclusions. The 108N, 51I and 437G mutations prevail in the populations of P. falciparum, indicating a cumulative effect of mutations and the need to continue surveillance for other changes which can lead to the total loss of the efficacy of sulphadoxine-pyrimethamine.

Options for clinical trials of pre and post-natal treatments for congenital toxoplasmosis

Clinical trials comparing different drug regimens and strategies for the treatment of congenital toxoplasmosis and its clinical manifestations in the liveborn child in different clinical settings should aim at formally evaluating the net benefit of existing treatments and at developing new therapeutic options. Currently, there is no ideal drug for congenital toxoplasmosis; future research should focus on the screening of new active drugs and on their pre-clinical and early clinical development, with a focus on pharmacokinetic/dynamic studies and teratogenicity. For the prenatal treatment of congenital toxoplasmosis, a trial comparing spiramycine to pyrimethamine-sulphadiazine and placebo would allow a formal estimation of the effect of both drugs in infected pregnant women. In newborn children, the net benefit of pyrimethamine-sulphadiazine should also be formally assessed. These trials will be implemented in settings where prenatal screening for Toxoplasma gondii is currently implemented. Trials should be carefully designed to allow for translation to other settings and modelling tools like cost-effectiveness analysis should be used to provide clinicians and founders with the best available evidence to establish recommendations.

Diagnosis of congenital toxoplasmosis: prenatal and neonatal evaluation of methods used in Toulouse University Hospital and incidence of congenital toxoplasmosis

The aim of this study was to determine the incidence of congenital toxoplasmosis (CT) and to assess the performances of prenatal and neonatal diagnoses. From 1994-2005, in Toulouse University Hospital, France, amniocentesis was performed on 352 pregnant women who were infected during pregnancy. All women were treated with spiramycin and pyrimethamine-sulfadoxine when prenatal diagnosis was positive. Among the 275 foetuses with follow-up, 66 (24 percent) were infected. The transmission rates of Toxoplasma gondii were 7 percent, 24 percent and 59 percent in the first, second and third trimesters, respectively. The sensitivity and specificity of PCR on amniotic fluid (AF) were 91 percent and 99.5 percent, respectively. One case was diagnosed by mouse inoculation with AF and six cases were diagnosed by neonatal or postnatal screening. The sensitivity and specificity of PCR on placentas were 52 percent and 99 percent, respectively. The sensitivity of tests for the detection of specific IgA and IgM in cord blood was 53 percent and 64 percent, respectively, and specificity values were 91 percent and 92 percent. In conclusion, PCR performed on AF had the highest levels of sensitivity and specificity for the diagnosis of CT. This permits an early diagnosis of most cases and should be recommended.

Gametocitemia en malaria falciparum tratada con amodiaquina o artesunato / Gametocitaemia in falciparum malaria treated with amodiaquine or artesunate

Introducción. Las relaciones de la gametocitemia de Plasmodium falciparum con el tratamiento antipalúdico han sido poco estudiadas en América. Objetivo. Describir relaciones de la gametocitemia falciparum con el tratamiento con amodiaquina-sulfadoxina-pirimetamina, artesunato-sulfadoxina-pirimetamina o amodiaquina-artesunato. Materiales y métodos. Se usó diseño experimental, aleatorio, no balanceado, no ciego. El seguimiento fue de 21-28 días. La eficacia terapéutica se clasificó según el protocolo de la Organización Mundial de la Salud, 1998. Resultados. Se evaluaron 241 pacientes en Turbo, El Bagre y Zaragoza (Antioquia, Colombia). Amodiaquina-sulfadoxina-pirimetamina tuvo igual eficacia que artesunato-sulfadoxina-pirimetamina y amodiaquina-artesunato para controlar las fallas terapéuticas el día 21. Hubo cuatro fallas (1,66 por ciento). Amodiaquina-sulfadoxina-pirimetamina fue menos eficaz que los tratamientos con artesunato para reducir la tenencia de gametocitos. La mayoría (56 por ciento) de nuestros pacientes no tenía gametocitos pretratamiento y nunca los desarrolló. El tiempo para eliminar los gametocitos que se tienen al iniciar el tratamiento no fue mayor cuando la gametocitemia inicial fue más alta. Conclusión. Los tres tratamientos fueron iguales en cuanto a eficacia terapéutica e incapacidad de eliminar los gametocitos en siete días.

Eficacia de la combinación amodiaquina más sulfadoxina-pirimetamina y de la cloroquina para el tratamiento del paludismo en Córdoba, Colombia, 2006 / Efficacy of the amodiaquine+sulfadoxine-pyrimethamine combination and of chloroquine for the treatment of malaria in Córdoba, Colombia, 2006

Introducción. La disminución de la eficacia de los medicamentos antipalúdicos en el mundo y en Colombia, dificulta el control de la enfermedad. Objetivo. Evaluar la eficacia terapéutica in vivo de la combinación amodiaquina más sulfadoxina-pirimetamina para el tratamiento del paludismo no complicado por Plasmodium falciparum y de la cloroquina para el tratamiento del paludismo por P. vivax en Tierralta, Córdoba. Materiales y métodos. Durante el período de mayo a noviembre de 2006, se realizaron estudios de eficacia in vivo siguiendo los protocolos estandarizados por la Organización Mundial de la Salud y la Organización Panamericana de la Salud, con algunas modificaciones. Se estudiaron pacientes mayores de dos años, con parasitemia entre 500 y 50.000 formas asexuales/µl, seleccionados conforme a los criterios de inclusión y exclusión previamente definidos. Se administró tratamiento supervisado y se realizó seguimiento clínico y parasitológico en los días 0 (inclusión), 1, 2, 3, 7, 14, 21 y 28. El desenlace se definió como respuesta clínica y parasitológica adecuada, fracaso terapéutico precoz o fracaso tardío al tratamiento. Resultados. De los pacientes evaluados, 50/53 (94,3 por ciento) (IC95 por ciento: 70 por ciento-100 por ciento) presentaron respuesta clínica y parasitológica adecuada al tratamiento con amodiaquina más sulfadoxina-pirimetamina para paludismo no complicado por P. falciparum, un paciente presentó fracaso terapéutico precoz y dos presentaron fracaso terapéutico tardío. Los 50 pacientes evaluados (100 por ciento) (IC95 por ciento: 74 por ciento-100 por ciento) presentaron respuesta clínica y parasitológica adecuada al tratamiento con cloroquina para el paludismo por P. vivax. Conclusiones. En Córdoba, la combinación amodiaquina más sulfadoxina-pirimetamina y la cloroquina son eficaces para el tratamiento del paludismo no complicado por P. falciparum y por P. vivax, respectivamente.

Chloroquine resistant Plasmodium falciparum malaria in Osogbo Nigeria: efficacy of amodiaquine + sulfadoxine-pyrimethamine and chloroquine + chlorpheniramine for treatment

Chloroquine (CQ) resistance in Plasmodium falciparum contributes to increasing malaria-attributable morbidity and mortality in Sub-Saharan Africa. Despite a change in drug policy, continued prescription of CQ did not abate. Therefore the therapeutic efficacy of CQ in uncomplicated falciparum malaria patients was assessed in a standard 28-day protocol in 116 children aged between six and 120 months in Osogbo, Southwest Nigeria. Parasitological and clinical assessments of response to treatment showed that 72 (62.1 percent) of the patients were cured and 44 (37.9 percent) failed the CQ treatment. High initial parasite density and young age were independent predictors for early treatment failure. Out of the 44 patients that failed CQ, 24 received amodiaquine + sulphadoxine/pyrimethamine (AQ+SP) and 20 received chlorpheniramine + chloroquine (CH+CQ) combinations. Mean fever clearance time in those treated with AQ+SP was not significantly different from those treated with CH+CQ (p = 0.05). There was no significant difference in the mean parasite density of the two groups. The cure rate for AQ+SP group was 92 percent while those of CH+CQ was 85 percent. There was a significant difference in parasite clearance time (p = 0.01) between the two groups. The 38 percent treatment failure for CQ reported in this study is higher than the 10 percent recommended by World Health Organization in other to effect change in antimalarial treatment policy. Hence we conclude that CQ can no more be solely relied upon for the treatment of falciparum malaria in Osogbo, Nigeria. AQ+SP and CH+CQ are effective in the treatment of acute uncomplicated malaria and may be considered as useful alternative drugs in the absence of artemisinin-based combination therapies.

Resistência à sulfadoxina-pirimetamina em Maputo, Moçambique: presença de mutações nos genes dhfr e dhps do Plasmodium falciparum / Sulfadoxine-pyrimethamine resistance in Maputo, Mozambique: presence of mutations in the dhfr and dhps genes of Plasmodium falciparum

Foram analisadas a freqüência e distribuição de mutações nos genes dihidrofolato redutase e dihidropteroato sintetase do Plasmodium falciparum, usando a metodologia de reação em cadeia da polimerase e polimorfismos de hidrólise por enzimas de restrição, em amostras de sangue infectado proveniente de crianças moçambicanas, residentes em Maputo. A análise foi feita antes e 7 dias após o tratamento com sulfadoxina-pirimetamina (S/P). Os resultados mostraram a ocorrência de mutações pontuais nos genes estudados e a presença de combinações de três alelos em dhfr (51Ile, 59Arg e 108Asn) e do quintúplo mutante (dhfr 51Ile, 59Arg, 108Asn e dhps 437Gly, 540Glu), ambas situações associadas à falha terapêutica no sétimo dia após tratamento com S/P. Esses achados mostram a importância de se estudar a resistência à S/P em Moçambique, e como os marcadores moleculares de resistência aos antimaláricos podem fornecer dados importantes para a política nacional de controlo da malária.

The frequency and distribution of mutations in Plasmodium falciparum, dihydrofolate reductase and dihydropteroate synthase genes were analyzed, using the polymerase chain reaction and restriction fragment length polymorphism methodology, in infected blood samples from Mozambican children living in Maputo, before and seven days after treatment with sulfadoxine/pyrimethamine (S/P). The results showed the occurrence of point mutations in the genes studied and the presence of combinations of three alleles in dhfr (51Ile, 59Arg and 108Asn) and "quintuple" mutant (dhfr 51Ile, 59Arg, 108Asn and dhps 437Gly, 540Glu). Both of these situations were associated with seven-day therapeutic failure, following treatment with S/P. These findings show the importance of studying S/P resistance in Mozambique, and how molecular markers for antimalarial resistance can provide important data for national malaria control policy.

Effects of pyrimethamine-sulphadoxine, chloroquine plus chlorpheniramine, and amodiaquine plus pyrimethamine-sulphadoxine on gametocytes during and after treatment of acute, uncomplicated malaria in children

The effects of pyrimethamine-sulphadoxine (PS), chloroquine plus chlorpheniramine, a H1 receptor antagonist that reverses chloroquine resistance in Plasmodium falciparum in vitro and in vivo (CQCP), and amodiaquine plus pyrimethamine-sulphadoxine (AQPS) on gametocyte production were evaluated in 157 children with acute, symptomatic, uncomplicated falciparum malaria who were treated with these drugs. PS was significantly less effective than CQCP or AQPS at clearing asexual parasitaemia or other symptoms of malaria. Gametocyte carriage on days 3, 7, and 14 were significantly higher in those treated with PS. The ratio of the density (per æl blood) of peripheral young gametocyte (PYG), that is, < stage III to peripheral mature gametocyte (PMG), that is, stage IV and V, an index of continuing generation of gametocytes, rose to 1 by day 7 of treatment in those treated with PS, but remained consistently below 1 in the other treatment groups. PYG-PMG density ratio increased significantly from day 0-14 in those treated with PS and CQCP (chi2 = 76, P = 0.000001 and chi2 = 42.2, P = 0.00001, respectively) but decreased significantly in those treated with AQPS (chi2 = 53.2, P = 0.000001). Both PS-sensitive and -resistant infections generated PYG (18 of 29 vs 13 of 20, chi2 = 0.04, P = 0.93) but PYG was present only in those with resistant response to CQCP. Combination of PS with amodiaquine (AQ), that is, (AQPS) resulted in less production of PYG, but in this setting, PYG was not indicative of response to AQPS. These data indicate that PS enhanced production or release of young gametocytes when used alone, but generated less young gametocytes when used in combination with AQ. PYG may be used as an indicator of response to CQCP but not PS or PS-based combination drugs.