Atypical Plasmodium vivax malaria in a traveler: bilateral hydronephrosis, severe thrombocytopenia, and hypotension

Antimalarial Drug Resistance and Novel Targets for Antimalarial Drug Discovery

Malaria is among the most devastating and widespread tropical parasitic diseases in which most prevalent in developing countries. Antimalarial drug resistance is the ability of a parasite strain to survive and/or to multiply despite the administration and absorption of medicine given in doses equal to or higher than those usually recommended. Among the factors which facilitate the emergence of resistance to existing antimalarial drugs: the parasite mutation rate, the overall parasite load, the strength of drug selected, the treatment compliance, poor adherence to malaria treatment guideline, improper dosing, poor pharmacokinetic properties, fake drugs lead to inadequate drug exposure on parasites, and poor-quality antimalarial may aid and abet resistance. Malaria vaccines can be categorized into three categories: pre-erythrocytic, blood-stage, and transmission-blocking vaccines. Molecular markers of antimalarial drug resistance are used to screen for the emergence of resistance and assess its spread. It provides information about the parasite genetics associated with resistance, either single nucleotide polymorphisms or gene copy number variations which are associated with decreased susceptibility of parasites to antimalarial drugs. Glucose transporter PfHT1, kinases (Plasmodium kinome), food vacuole, apicoplast, cysteine proteases, and aminopeptidases are the novel targets for the development of new antimalarial drugs. Therefore, this review summarizes the antimalarial drug resistance and novel targets of antimalarial drugs.

Mapping malaria in municipalities of the Coffee Triangle region of Colombia using Geographic Information Systems (GIS)

Geographical Information Systems (GIS) have been used extensively for the development of epidemiological maps of malaria but not in the Coffee Triangle region of Colombia, endemic for P. vivax, P. falciparum and P. malariae. Surveillance case data (2007-2011) were used to estimate annual incidence rates per Plasmodium spp. (cases/100,000 pop) to develop the first malaria maps in the 53 municipalities of this region (departments Caldas, Quindío, Risaralda). The GIS software used was Kosmo Desktop 3.0RC1(®). Thirty thematic maps were developed according to the municipalities, years, parasite etiology, and uncomplicated and complicated cases. A total of 6582 cases were reported (6478 uncomplicated and 104 complicated, 77.8% Risaralda), for a cumulated rate of 269.46 cases/100,000 pop. Among uncomplicated cases, 5722 corresponded to P. vivax (234.25 cases/100,000 pop), 475 to P. falciparum (19.45 cases/100,000 pop), 8 to P. malariae (0.33 cases/100,000 pop) and 273 mixed (P. falciparum/P. vivax) (11.18 cases/100,000 pop). The highest rate reported was in the more undeveloped and rural municipality of Risaralda (Pueblo Rico, 57.7 cases/1000 pop, 2009). The burden of disease was concentrated in one department (>75% of the region). The use of GIS-based epidemiological maps helps to guide decision-making for the prevention and control of this public health problem that still represents a significant issue in the region and the country, particularly in children.

Intracerebral bleed, right haemiparesis and seizures: an atypical presentation of vivax malaria

Falciparum malaria is notoriously known to produce life-threatening complications. Despite growing reports of chloroquine resistance and severe disease, vivax malaria continues to be viewed as a benign disease. We report a rare case of a 47-year-old healthy man from a malaria-endemic region, presenting with intracerebral bleed, right haemiparesis, aphasia and seizures following vivax malaria. This was successfully managed conservatively, without any neurosurgical intervention, with combination therapy of intravenous artesunate, oral hydroxychloquine and primaquine. In a country where Plasmodium vivax is responsible for majority of cases of malaria, it is high time the national malaria control programmes focus on the elimination of P. vivax in addition to its more dangerous counterpart, P. falciparum.

Plasmodium vivax malaria complicated by splenic infarct

An 11-year-old girl presented with Plasmodium vivax malaria complicated by shock and acute renal failure. The diagnosis of malaria was based on demonstration of trophozoites of P. vivax in the peripheral blood smear and a positive rapid malarial antigen test for P. vivax but negative for P. falciparum. She responded to parenteral artesunate and supportive care. During the course of her infection, she developed pain in her left hypochondrium. Ultrasonography showed multiple hypo-echoic lesions in the spleen and CT scan revealed multiple splenic infarcts. Management was restricted to close clinical monitoring and analgesia. We consider that this is the first report of splenic infarct complicating the course of childhood P. vivax malaria in the English literature. Physicians should suspect and investigate for this rare complication if a patient with malaria complains of left upper quadrant abdominal pain, pleuritic left lower chest pain and/or enlarging tender splenomegaly during the course of malaria infection.

Evidence and implications of mortality associated with acute Plasmodium vivax malaria

Vivax malaria threatens patients despite relatively low-grade parasitemias in peripheral blood. The tenet of death as a rare outcome, derived from antiquated and flawed clinical classifications, disregarded key clinical evidence, including (i) high rates of mortality in neurosyphilis patients treated with vivax malaria; (ii) significant mortality from zones of endemicity; and (iii) the physiological threat inherent in repeated, very severe paroxysms in any patient, healthy or otherwise. The very well-documented course of this infection, with the exception of parasitemia, carries all of the attributes of "perniciousness" historically linked to falciparum malaria, including severe disease and fatal outcomes. A systematic analysis of the parasite biomass in severely ill patients that includes blood, marrow, and spleen may ultimately explain this historic misunderstanding. Regardless of how this parasite is pernicious, recent data demonstrate that the infection comes with a significant burden of morbidity and associated mortality. The extraordinary burden of malaria is not heavily weighted upon any single continent by a single species of parasite-it is a complex problem for the entire endemic world, and both species are of fundamental importance. Humanity must rally substantial resources, intellect, and energy to counter this daunting but profound threat.

Clinical and laboratory profile of Plasmodium vivax malaria patients hospitalized in Apartadó,

Introducción. La malaria representa un problema de salud pública en la región de Urabá, donde se registran tasas superiores a las del departamento de Antioquia; la carga de malaria por Plasmodium vivax es de 78,7 % y poco se ha explorado su perfil en la región.Objetivos. Con el presente estudio se pretende conocer las características clínicas y de laboratorio de los pacientes hospitalizados por malaria por P. vivax en Apartadó.Materiales y métodos. Se revisaron las historias clínicas de pacientes con malaria por P. vivax que requirieron manejo hospitalario en el Hospital “Antonio Roldán Betancur”, Empresa Social del Estado, durante los años 2004-2007.Resultados. Se hospitalizaron 359 pacientes con malaria por P. vivax, de los cuales, el 23,1 % (83/359 casos) se complicó por anemia grave (51,8 %, 43/83), por trombocitopenia grave (15,6 %, 13/83) y por hiperbilirrubinemia (7,2 %, 6/83); algunos pacientes satisfacían varios criterios simultáneamente, incluyendo un caso de síndrome de dificultad respiratoria aguda. Los datos de laboratorio más significativos mostraron disminución de los niveles de hemoglobina, hematocrito y plaquetas, con aumento en los niveles de transaminasas y bilirrubinas. Sólo el 4,82 % (4/83) de los pacientes con malaria complicada, recibió tratamiento con quinina intravenosa, ninguno falleció.Conclusiones. Se destaca en este trabajo la frecuencia importante de malaria complicada por P. vivax, particularmente en los menores de cinco años, en la región de Urabá, y la necesidad de fortalecer el conocimiento de la guía para la atención clínica integral del paciente con malaria, entre el personal de salud, para hacer un diagnóstico clínico correcto y ofrecer el tratamiento apropiado.

Severe Plasmodium malariae malaria in a patient with multiple susceptibility genes

We present a case of severe malaria due to Plasmodium malariae. Genetic testing showed that the patient was homozygous for five important gene polymorphisms previously shown to be associated with increased susceptibility to, and/or severity of, severe sepsis. Our case suggests that P. malariae may cause life-threatening disease, and that disease severity may be linked, at least in part, to multiple susceptibility genes.

Resistance to therapies for infection by Plasmodium vivax

The gravity of the threat posed by vivax malaria to public health has been poorly appreciated. The widely held misperception of Plasmodium vivax as being relatively infrequent, benign, and easily treated explains its nearly complete neglect across the range of biological and clinical research. Recent evidence suggests a far higher and more-severe disease burden imposed by increasingly drug-resistant parasites. The two frontline therapies against vivax malaria, chloroquine and primaquine, may be failing. Despite 60 years of nearly continuous use of these drugs, their respective mechanisms of activity, resistance, and toxicity remain unknown. Although standardized means of assessing therapeutic efficacy against blood and liver stages have not been developed, this review examines the provisional in vivo, ex vivo, and animal model systems for doing so. The rationale, design, and interpretation of clinical trials of therapies for vivax malaria are discussed in the context of the nuance and ambiguity imposed by the hypnozoite. Fielding new drug therapies against real-world vivax malaria may require a reworking of the strategic framework of drug development, namely, the conception, testing, and evaluation of sets of drugs designed for the cure of both blood and liver asexual stages as well as the sexual blood stages within a single therapeutic regimen.