RESUMEN

Malaria is a global parasitic infection that leads to substantial illness and death. The most commonly-used drugs for treatment of malaria vivax are primaquine and chloroquine, but they have limitations, such as poor adherence due to frequent oral administration and gastrointestinal side effects. To overcome these limitations, we have developed nano-sized solid dispersion-based dissolving microarray patches (MAPs) for the intradermal delivery of these drugs. In vitro testing showed that these systems can deliver to skin and receiver compartment up to ≈60% of the payload for CQ-based dissolving MAPs and a total of ≈42% of drug loading for PQ-based dissolving MAPs. MAPs also displayed acceptable biocompatibility in cell tests. Pharmacokinetic studies in rats showed that dissolving MAPs could deliver sustained plasma levels of both PQ and CQ for over 7 days. Efficacy studies in a murine model for malaria showed that mice treated with PQ-MAPs and CQ-MAPs had reduced parasitaemia by up to 99.2%. This pharmaceutical approach may revolutionise malaria vivax treatment, especially in developing countries where the disease is endemic. The development of these dissolving MAPs may overcome issues associated with current pharmacotherapy and improve patient outcomes.

Asunto(s)

RESUMEN

BACKGROUND: Some anti-malarial drugs often cause haemolytic anaemia in glucose-6-phosphate-dehydrogenase deficiency (G6PDd) patients. This study aims to analyse the association of G6PDd and anaemia in malaria patients receiving anti-malarial drugs. METHODS: A literature search was performed in major database portals. All studies searched using keywords with Medical Subject Headings (MeSH) were included, without date or language restriction. Pooled mean difference of haemoglobin and risk ratio of anaemia were analysed using RevMan. RESULTS: Sixteen studies comprising 3474 malaria patients that included 398 (11.5%) with G6PDd were found. Mean difference of haemoglobin in G6PDd/G6PD normal (G6PDn) patients was - 0.16 g/dL (95% CI - 0.48, 0.15; I2 5%, p = 0.39), regardless of the type of malaria and dose of drugs. In particular with primaquine (PQ), mean difference of haemoglobin in G6PDd/G6PDn patients with dose < 0.5 mg/kg/day was - 0.04 (95% CI - 0.35, 0.27; I2 0%, p = 0.69). The risk ratio of developing anaemia in G6PDd patients was 1.02 (95% CI 0.75, 1.38; I2 0%, p = 0.79). CONCLUSION: Single or daily standard doses of PQ (0.25 mg/kg/day) and weekly PQ (0.75 mg/kg/week) did not increase the risk of anaemia in G6PDd patients.

Asunto(s)

RESUMEN

Introducción: La malaria es transmitida por la picadura de los mosquitos del género Anopheles. La región Tumbes ubicada en la frontera norte del Perú, pese a la presencia permanente del vector estuvo libre de malaria presentando solo casos importados esporádicos. Material y Métodos: Se realizó un estudio de serie de casos de un brote de malaria por P. vivax asociado a un conglomerado de casos importados en el contexto de masiva migración venezolana al Perú. Resultados: Se describen las actividades de control implementadas a través de metodología de cerco epidemiológico modificado para el control de la reintroducción de la enfermedad; se detectó la transmisión del brote relacionada con migrantes venezolanos en tránsito. Conclusiones: la reintroducción de la malaria en la región Tumbes se relaciona a casos importados por migración venezolana. Los cercos epidemiológicos modificados permitieron mejorar la captación de casos in situ.

Background: Malaria is transmitted by the bite of mosquitoes which belong to the genus Anopheles. The Tumbes region, located in the northern border of Peru, despite the permanent presence of the vector, was free from malaria transmission, and there are only sporadic imported cases. Material and Methods: A case series study of an outbreak of malaria caused by P. vivax associated with a conglomerate of imported cases was carried out in the context of massive Venezuelan migration to Peru. Results: The control activities implemented through the modified epidemiological fence methodology to control the reintroduction of the disease are described; transmission of the outbreak related to Venezuelan migrants in transit was detected. Conclusions: the reintroduction of malaria in the Tumbes region was related to cases imported from Venezuela. The modified epidemiological fences made it possible to improve the collection of cases in situ.

RESUMEN

Introducción. La tafenoquina fue aprobada en el 2018 por la Food and Drug Administration de Estados Unidos y, en el 2019, por la Therapeutic Goods Administration en Australia. Su administración en dosis única y su mecanismo de acción en las fases aguda y latente han sido objeto de estudio para cambiar el esquema de tratamiento de la malaria por Plasmodium vivax. Objetivo. Evaluar la evidencia científica disponible sobre la eficacia de la tafenoquina en la profilaxis y el tratamiento de la malaria por P. vivax, entre el 2009 y el 2019. Materiales y métodos. Se establecieron los descriptores MeSH y DeCS. Se utilizó la sintaxis ((Malaria Vivax) AND (tafenoquine) AND (prophylaxis)) OR [(Malaria Vivax) AND (tafenoquine) AND (relapse)] en las siguientes bases de datos: Pubmed, The Cochrane Central Register of Controlled Clinical Trials (CENTRAL), ISIS Web of Science, Lilacs y Scopus. Los resultados obtenidos se sometieron a análisis crítico (matriz CASPE). El análisis cuantitativo se realizó utilizando la diferencia de riesgos en análisis de supervivencia (Kaplan-Meier) en los tres artículos finales. Resultados. Se sometieron tres estudios a metaanálisis (Llanos-Cuentas, 2014; Llanos- Cuentas, 2019, y Lacerda, 2019) para evaluar la eficacia del tratamiento con tafenoquina en comparación con primaquina. Se obtuvo una diferencia de riesgo global de 0,04 (IC95% 0-0,08; p=0,07). La tafenoquina no mostró inferioridad en la eficacia del tratamiento frente al esquema de primaquina. Conclusión. La tafenoquina es una alternativa que mejora el cumplimiento del tratamiento, lo que podría acercar a Colombia a las metas de la Estrategia Técnica Mundial contra la Malaria, 2016-2030.

Introduction: Tafenoquine was approved in 2018 by the Food and Drug Administration in the United States and in 2019 by the Therapeutic Goods Administration in Australia. Its administration in a single dose and its mechanism of action in the acute and latent phases of the disease have been studied to change the treatment regimen for Plasmodium vivax malaria. Objective: To evaluate the available scientific evidence of the efficacy of tafenoquine in prophylaxis and treatment between 2009 and 2019. Materials and methods: We established the MeSH and DeCS descriptors and we used the syntax ((Malaria Vivax) AND (tafenoquine) AND (prophylaxis)) OR [(Malaria Vivax) AND (tafenoquine) AND (relapse)] in the following databases: Pubmed, The Cochrane Central Register of Controlled Clinical Trials (CENTRAL), ISIS Web of Science, Lilacs, and Scopus. The results obtained were subjected to critical analysis (CASPE matrix). The quantitative analysis was performed with risk differences in survival analysis (Kaplan Meier) in the final three articles. Results: Three studies underwent meta-analysis (Llanos-Cuentas, 2014; Llanos-Cuentas, 2019, and Lacerda, 2019) to evaluate the efficacy of the treatment with tafenoquine compared to primaquine. A global risk difference of 0.04 was obtained (95% CI: 0.00-0.08; p=0.07). Tafenoquine did not show inferiority in the efficacy of treatment compared to the primaquine scheme. Conclusion: Tafenoquine is a therapeutic alternative to primaquine that improves adherence, which could bring Colombia closer to the goals of the World Technical Strategy against Malaria 2016-2030.

Asunto(s)

RESUMEN

INTRODUCTION: Plasmodium vivax malaria causes significant disease burden worldwide, especially in Latin America, Southeast Asia, and Oceania. P. vivax is characterized by the production of liver hypnozoites that cause clinical relapses upon periodic activation. Primaquine, an 8-aminoquinoline drug, has been the standard of care for decades to treat liver-stage P. vivax malaria; however, it requires long treatment regimens (one to two weeks) that lead to poor adherence and thus clinical relapses. Tafenoquine (TFQ), a newly available and efficacious single-dose 8-aminoquinoline, aims to address this challenge. Safe administration is possible when paired with the use of glucose-6-phosphate dehydrogenase (G6PD) diagnostics to prevent 8-aminoquinoline-induced hemolysis in patients with underlying G6PD deficiency (G6PDd). AREAS COVERED: In this review, the authors present the recent literature regarding the pharmacology, efficacy, safety, and tolerability of TFQ and highlight regional differences in these areas. The authors also discuss the potential for TFQ, complemented with primaquine PQ and effective screening for G6PDd, to improve P. vivax clinical management and facilitate targeted mass drug administration in communities to decrease transmission. EXPERT OPINION: Clinical studies show therapeutic efficacy of TFQ as well as a good performance in terms of safety and tolerability. Additional research regarding the effectiveness and safety TFQ in malaria elimination strategies, such as targeted or mass drug administration, are needed.

Asunto(s)

RESUMEN

Background: Malaria remains endemic in Solomon Islands, but data on malaria in the provinces of Solomon Islands are limited. This study from Makira-Ulawa Province aimed to identify the most prevalent strain of malaria and assess if the available rapid diagnostic test (RDT) was effective in Kirakira Hospital. Methods: Forty-five patients who presented to Kirakira Hospital with symptoms of fever had a positive malaria parasite smear during a 4-week period in 2017. The parasite count for each smear was calculated. Simultaneous testing using the CareStart Malaria HRP2/pLDH (Pf/pan) Combo RDT was conducted. The data for all malaria parasite smears performed in Makira-Ulawa Province in 2016 were collated for comparison. Results: All 45 patients diagnosed with malaria in a 4-week period in 2017 were positive for Plasmodium vivax. The median parasite load was 280 parasites per µL (range, 160 to 640 parasites per µL). None of the 45 CareStart RDTs performed was positive. In 2016, 5,505 of 17,195 patients (32.0%) screened had malaria parasites detected on a malaria parasite smear. P vivax was detected in 5,212 (94.7%) and Plasmodium falciparum in 285 (5.2%) of patients with malaria. Conclusion: P vivax is the predominant strain of malaria present in Makira-Ulawa Province. RDTs were not helpful in the diagnosis of malaria at Kirakira Hospital. The parasite load detected in the 45 patients diagnosed with malaria in this study was low. A focus on attempting to eradicate P vivax in the community through improved compliance with treatment protocols is suggested as a possible way forward to best manage malaria in Makira-Ulawa Province.

RESUMEN

A clinical case is presented here of a patient from Afganistan. We found intraerythrocytic parasites consistent with malaria vivax. Additionally extraerythrocytic structures were seen. First a co-infection with Borrelia recurrentis was discussed later these structures were identified as male plasmodia microgametes resulting from exflagellation.

RESUMEN

BACKGROUND: Imported cases of multidrug resistant Plasmodium falciparum and treatment failure with artemisinin-based regimens, although rare, have been described also in Western countries and their management is often challenging. This is also due to an inadequate knowledge and implementation of health prevention measures. CASE REPORT: A complex case of imported malaria caused by Plasmodium vivax/P. falciparum isolates in a patient who was not taking chemoprophylaxis while he was travelling in Cambodia is reported in this article. After failures of artemisinin-based and both oral and intravenous quinine-based regimens, a multidrug resistant P. falciparum was detected. The patient was successfully treated with atovaquone-proguanil. CONCLUSIONS: This experience highlights the importance of a careful management that should be based not only on the most up-to-date guidelines, but also on the awareness of a rapidly evolving scenario.

Asunto(s)

RESUMEN

INTRODUCTION: Malaria occurring in pregnancy is associated with considerable maternal and perinatal morbidity. In India, the problem is compounded by dual parasitological aetiology of Plasmodiumvivax (P.vivax) and Plasmodium falciparum (P.falciparum). AIM: To compare the outcome of infections by P. vivax and P.falciparum species among pregnant women in a hospital setting. MATERIALS AND METHODS: Pregnant women who tested positive for malaria either by microscopy of peripheral blood smear or ELISA test for double antigen were enrolled in the study. They were followed up till their delivery and discharge from hospital. Demographic, clinical and laboratory data was collected at enrolment, on event of complication and at delivery. Data was analyzed for univariate and multivariate associations. RESULTS: There were 64 pregnant women diagnosed with malaria. A total of 76.6% study subjects had vivax infection rest were infected with p. falciparum. Anaemia (84%) was the commonest complication. A total of 60.9% women had pathological placenta. Preterm delivery, low birth weight and Apgar score <7 were the adverse pregnancy outcomes which were more frequent with falciparum infection. There were three perinatal deaths. Multigravidas were at significantly higher risk for low birth weight and low Apgar score of newborn. Infection in later trimester was associated with low Apgar score. CONCLUSION: Both types of malaria cause considerable morbidity in pregnant women. More cases occurred among primigravida but multigravida and later trimester of pregnancy had more severe disease.

RESUMEN

Plasmodium vivax tem sido reconhecido por sua capacidade de causar malária grave, oque torna prioritário os estudos acerca dos mecanismos patogênicos associados a essa espécie.Dado o caráter inflamatório exibido pela malária vivax, faz-se relevante estudar os fatoresgenéticos do hospedeiro vertebrado que podem influenciar o curso da doença. Nesse sentido,o presente trabalho investigou a influência da variabilidade genética de componentesplaquetários e do inflamossoma sobre a morbidade na infecção por P. vivax. Maisespecificamente, a primeira hipótese avaliada foi a de que alterações clínicas e hematológicasna malária vivax estão envolvidas com polimorfismos em genes de receptores plaquetários,relacionados ao aumento da adesão e/ou agregação das plaquetas: integrina α2 (C807T),integrina β3 (T1565C) e glicoproteína GPIbα (T-5C). A partir do estudo de aproximadamente200 indivíduos sintomáticos infectados por P. vivax, foi possível confirmar que ospolimorfismos do receptor para colágeno (α2) e do receptor para fator de von Willebrand(GPIbα) estão associados a duas das complicações mais frequentes na malária:trombocitopenia grave e anemia. A segunda hipótese investigada foi a de que polimorfismosem genes de componentes do inflamossoma – plataforma molecular capaz de desencadear aprodução de citocinas inflamatórias – estão associados à morbidade em pacientes infectadospor P. vivax. Nossos achados confirmaram essa hipótese e sugeriram que polimorfismos nosgenes de NLRP1, NLRP3 e CARD8 podem contribuir para as alterações clínicas ehematológicas observadas nos indivíduos estudados. Em conjunto, os dados aqui apresentadosconstituem a primeira demonstração de que a variabilidade genética de receptoresplaquetários e componentes do inflamossoma pode influenciar na patogenia da maláriacausada por P. vivax. Estudos futuros visando esclarecer o papel da cascata de coagulação inflamaçãona morbidade dessa doença fazem-se necessários...

Asunto(s)

RESUMEN

Objective: To evaluate pulmonary manifestations in patients infected with Plasmodium vivax. MethOds: This was a cross- sectional, retrospective study of 50 patients diagnosed in 2006 to 2008 with vivax malaria at the Evandro Chagas Institute and referred to the University Hospital João de Barros Barreto to examine the pulmonary manifestations. Results: 72% of the patients were men, 28% were 21 to 30 years of age, 30% had parasitaemia 50 to 2000 p/mm3, 88%, 94% and 92% of the patients presented respectively with fever, chills and headache respectively, 56% of the patients had cough, 62% felt breathlessness, 28% presented dyspnea and 86% experienced chest pain. COnClusiOn: The majority of patients surveyed had parasitaemia in the range 50 to 2000 p/mm3. The classic triad fever, chills and headache was present in most patients. Among pulmonary manifestations, cough, chest pain and shortness of breath were reported by the majority of patients.(AU)

Objetivo: Analisar as manifestações pulmonares em pacien- tes infectados por Plasmodium vivax. Métodos: Estudo transversal realizado por meio da análise de 50 prontuários de pacientes diagnosticados com malária vivax entre 2006 a 2008, no Instituto Evandro Chagas, e encaminhados para o Hospital Universitário João de Barros Barreto para análise das manifes- tações pulmonares. ResultadOs: Observou-se que 72% dos pacientes eram homens, 28% possuíam de 21 a 30 anos de idade, 30% apresentaram parasitemia de 50 a 2000 p/mm3. Entre as manifestações clínicas, 88%, 94% e 92% dos pacientes apresentaram, respectivamente, febre, calafrio e cefaleia, 56% apresentaram tosse, 62% sentiram falta de ar, 28% dispneia e 86% dor torácica. COnClusãO: A maioria dos pacientes pesquisados apresentou parasitemia no intervalo de 50 a 2000 p/mm3. A tríade clássica da malária esteve presente na maioria, já dentre as manifestações pulmonares pesquisadas, a tosse, a dor torácica e a falta de ar corresponderam aos sintomas mais relatados pelos pacientes.(AU)

Asunto(s)

RESUMEN

One of the most important aspects regarding the therapeutic efficacy of antimalarials is its quantification in biologic fluids. The detection and measurement of antimalarial drug levels is important for demonstrating (1) adequate absorption of the drug being given, (2) compliance in taking the full regimen required for treatment and (3) the level of drug in the blood at any time during the test period that parasites reappear. There is a lack of validated methods that simultaneously quantify different antimalarials administered at the same time, such as the use of chloroquine (CQ) and primaquine (PQ) in infections caused by Plasmodium vivax. In this study, a bioanalytical method was validated for the simultaneous quantification of primaquine (PQ), chloroquine (CQ) and desethylchloroquine (DSCQ) in human plasma using liquid-liquid extraction and high performance liquid chromatography with a diode array detector (HPLC-DAD). The PQ was evaluated over a concentration range of 100-3000 nM and the CQ and DSCQ was evaluated over a concentration range of 20-2000 nM. The selectivity of the method was verified by checking for interference by commonly used antimalarials and plasma samples. The accuracy and precision of the method was assessed for drugs spiked into human plasma and recoveries of 83.7%, 92.3%, and 76.5% were obtained for CQ, DSCQ, and PQ, respectively. The applicability of this method was also demonstrated with blood samples from patients with vivax malaria that received combination CQ plus PQ treatment. The simultaneous detection and accurate measurement of CQ, DSCQ, and PQ levels in human plasma provides an important and economical method for validating and monitoring sensitivity/resistance of P. vivax to more common treatment regimen.

Asunto(s)

RESUMEN

A 73-year-old woman came to the casualty ward with symptoms of syncopal attacks, weakness, fever with chills and rigors. A provisional diagnosis of Plasmodium vivax malaria was made after the blood investigations. She had deranged renal function tests, altered sensorium and low platelet count. Repeated tests for P. falciparum (Card test) were negative. Glucose-6-Phosphate dehydrogenise (G6PD) levels were within normal limits. Treatment for P. vivax was started with intravenous quinine initially followed by oral quinine for a period of seven days and patient responded to the treatment and was discharged within 2 weeks of admission. Most of the cases of P. vivax present with typical and predictable features, although atypical cases with characteristics of P. falciparum can occur, especially in the elderly.

RESUMEN

No Brasil, foram descritas duas espécies de plasmódios simianos, Plasmodium brasilianum e Plasmodium simium, que são morfológica, genética e imunologicamente similares aos plasmódios humanos Plasmodium malariae e Plasmodium vivax, respectivamente. Plasmodium brasilianum infecta naturalmente macacos das famílias Cebidae, Aotidae, Pitheciidae e Atelidae, e foi detectado em uma ampla região geográfica. Já P. simium foi encontrado em uma área muito mais restrita, com descrições apenas nas regiões Sul e Sudeste, infectando naturalmente somente os gêneros Alouatta e Brachyteles, da família Atelidae. Apesar da malária no Brasil estar restrita como endemia à região amazônica, também são descritos casos da doença na região extra-amazônica, entre eles casos autóctones de malária,como os notificados em áreas de Mata Atlântica. Sugere-se que a manutenção destes casos envolva a presença de macacos infectados, que podem atuar como reservatórios da doença.Portanto, estudos moleculares das espécies de plasmódios simianos são fundamentais para o entendimento da real prevalência da doença, da dinâmica de transmissão, diversidade dos parasitos, assim como para esclarecer as relações filogenéticas entre as diferentes espécies de Plasmodium. O relato recente de casos autóctones no estado do Rio de Janeiro nos motivou a investigar a malária simiana na região...

Asunto(s)

RESUMEN

El Plasmodium vivax muestra una alta variabilidad genética durante episodios recurrentes de la enfermedad. Objetivos: Determinar la variabilidad genética de P. vivax y los patrones de recurrencia durante la malaria asintomática. Diseño: Estudio descriptivo analítico. Institución: Laboratorio de Investigación en Enfermedades Infecciosas-Universidad Peruana Cayetano Heredia. Población: Individuos provenientes de Mazán-Iquitos, región endémica en malaria. Intervención: Se analizó 222 individuos con dos muestras de sangre secuenciales, entre junio de 2006 y noviembre de 2008. Principales medidas de resultados: Identificación de P. vivax, genotipificación en base al gen pvmsp3-α, variabilidad genética de P. vivax y patrones de recurrencia. Resultados: Primera evaluación: Positivos a P. vivax 191/222 (86%), a P. falciparum 2/222 (0,9%), con infección mixta 21/222 (9,5%) y negativos 8/222 (3,6%). Segunda evaluación: Permanecieron positivos a P. vivax 180/191 (94,2%). La genotipificación por nested PCR y digestión enzimática mostró haplotipos policlonales en 17/180 (9,4%) y monoclonales en 163/180 (90,6%). Se observó haplotipos diferentes (reinfección) en 88/180 (48,9%) y haplotipos idénticos (relapso) en 75/180 (41,7%). Conclusiones: Existió una alta variabilidad genética de P. vivax, y los patrones de recurrencia, basados en la genotipificación, indicaron diferencias entre reinfecciones y relapsos en individuos asintomáticos para malaria en Mazán, Iquitos.

Plasmodium vivax displays a high genetic variability for recurrent episodes of illness. Objectives: To determine the genetic variability of P. vivax and patterns of recurrence in asymptomatic malaria. Design: Descriptive analytical. Setting: Laboratory of Infectious Disease Research, Universidad Peruana Cayetano Heredia. Population: Individuals from Mazan, Iquitos, Peru, a malaria endemic region. Intervention: Between June 2006 and November 2008, 222 individuals were analyzed with two sequential blood samples. Main outcome measures: Identification of P. vivax, genotyping based on gene pvmsp3-α, genetic variability of P. vivax and patterns of recurrence. Results: First evaluation: Positive for P. vivax 191/222 (86%), P. falciparum 2/222 (0.9%), mixed infection 21/222 (9.5%) and negative 8/222 (3.6%). Second evaluation: 180/191 (94.2%) remained positive for P. vivax. Genotyping by nested PCR and enzymatic digestion showed polyclonal haplotypes in 17/180 (9.4%) and monoclonal in 163/180 (90.6%). Different haplotypes (reinfection) were observed in 88/180 (48.9%) and identical haplotypes (relapse) in 75/180 (41.7%). Conclusions: There was P. vivax high genetic variability and patterns of malaria recurrence based on genotyping showed differences between reinfection and relapse in asymptomatic individuals in Mazan, Iquitos.

RESUMEN

We report an unusual case of Plasmodium vivax malaria that occurred in a 22-year-old ankylosing spondylitis patient after initiating adalimumab therapy. P. falciparum malaria was initially included as a possible differential diagnosis due to hyperparasitemia and similar features in the peripheral blood smear. The patient was successfully treated with conventional therapy for P. vivax malaria.

Asunto(s)

RESUMEN

Objective To observe platelet dynamics in a monkey infected with Plasmodium cynomolgi before and after treatments with antibiotics and antimalarial drug. Methods One experimental monkey was examined for parasite density and platelet count 2 days after parasite inoculation. Observation without treatment continued for 24 days after the parasite was detected in the blood sample of the monkey. Then the monkey was treated with Azithromycin (total 1500 mg) for 3 days. Thirty days after parasite detection in the blood, the monkey was treated with Artesunate for 5 days. Parasite density and platelet count were monitored daily during treatments. The result was compared with that from a healthy monkey as control. Results The experimental monkey's platelet count was 240× 109/L before infection. When parasite density was 2/100 white blood cells (WBC),platelet count increased to 540 × 109/L. During the subsequent period of infection, parasite density fluctuated at (1-60)/100 WBC, and the platelet count reduced to a persistent level of (130-150)×109/L. After the infected monkey was treated with Azithromycin, parasite density reduced initially but subsequently fluctuated at (16-64)/100 WBC. Meanwhile, platelet count was restored to 234.5 × 109/L.The infected monkey was treated with Artesunate and parasite clearance time was 64 hours, and the mean platelet count was 247 × 109/L after treatment. Conclusion Azithromycin and Artesunate treatment have direct influence on the recovery of platelet counts during malaria infection in monkeys.

RESUMEN

We compared light microscopy examination and a semi-nested multiplex PCR [SnM-PCR] assay in endemic areas of the Islamic Republic of Iran. A total of 68 individuals with malaria-positive and suspected malaria symptoms were included in the study. Giemsa-stained thick blood films were examined under a light microscope for malaria parasites in 100 and 200 fields. DNA was extracted from blood samples and SnM-PCR based on the amplification of the small subunit ribosomal RNA [ssrRNA] gene sequences was applied. Microscopical examination showed that 48.5% [33.8% P. vivax and 14.7% P.falciparum] and 50% [35.3% P. vivax and 14.7% P.falciparum] of the samples were positive in 100 and 200 fields respectively. SnM-PCR showed the same results as the 200 field microscopy

Asunto(s)

RESUMEN

Two cases of malaria by Plasmodium vivax relapsed after treatment with drugs in doses recommended by the Ministry of Health are presented. Both patients were overweight and were followed in the Federal District, an area considered free from vector transmission of the disease. Radical cure was obtained after medication with the same drugs in weight proportional doses.

São apresentados dois casos de pacientes com malária por Plasmodium vivax que apresentaram recaídas após tratamento com medicamentos em doses indicadas pelo Ministério da Saúde. Ambos os pacientes tinham pesos elevados e foram acompanhados no Distrito Federal, área considerada sem transmissão vetorial da doença. A cura radical foi obtida após medicação em dose proporcional ao peso corpóreo dos pacientes.

Asunto(s)

RESUMEN

Introducción: se ha evaluado poco en el mundo la eficacia del tratamiento con cloroquinaprimaquina para el ataque agudo y, sobre todo, para las recurrencias del paludismo vivax en niños; esos estudios en América Latina son muy escasos y casi inexistentes en Colombia.Objetivo: evaluar la eficacia de dos dosificaciones de primaquina en menores de 18 años.Materiales y métodos: estudio clínico controlado, no enmascarado, con asignación aleatoria del tratamiento. Se evaluaron dos grupos según la dosis de primaquina: 0,50 mg/kg/día por 7 días (0,50-7) frente a 1,17 mg/kg/día por 3 días (1,17-3).Resultados: A. Curación del ataque agudo: eficacia del 100% en los dos grupos; B. Prevención de las recurrencias durante 120 días: ocurrieron recurrencias en 68,4% de los niños tratados con el esquema 1,17-3, y en 34,2% de los que recibieron el régimen 0,50-7.Conclusiones: 1. La proporción de recurrencias a los 120 días en niños tratados con el esquema 0,50-7 (34,2%) fue significativamente menor que la de los niños que recibieron el régimen 1,17-3 (68,4%). 2. El tiempo de administración de una misma dosis total de primaquina influye en su eficacia contra las recurrencias: a menos días, menor eficacia.

Introduction: Worldwide, the efficacy of cloroquine-primaquine for treating acute Plasmodiumvivax malarious attacks has not been thoroughly evaluated. In Latin America such studies arescarce, and in Colombia, almost nonexisting. Objective: To assess the efficacy of two regimens foradministration of primaquine in children aged less than18 years. Methodology: A clinical, controlled, unmasked studywas carried out, with randomized administration of twoprimaquine regimens, namely: 0.50 mg/kg/day for 7days (0.50-7) vs. 1.17 mg/kg/day for 3 days (1.17-3). Results: A. Healing of the acute attack: efficacy was100% in both groups. B. Prevention of recurrencesduring 120 days: recurrences occurred in 68.4% ofchildren treated with the 1.17-3 regimen, and in 34.2%of those receiving the 0.5-7 one. Conclusions: 1. Proportion of recurrences during the120 days follow-up was significantly lower (34.2%) inchildren receiving the 0.50-7 regimen than in thosetreated with the 1.17-3 one (68.4%). The length ofadministration of the same total dose of primaquineinfluenced its efficacy against recurrences: shorterperiods of administration were associated with lesserefficacy.

Asunto(s)