Yvone Maia Brustoloni

Sensitivity and specificity of polymerase chain reaction in Giemsa-stained slides for diagnosis of visceral leishmaniasis in children

The aim of this study was to evaluate the sensitivity and specificity of polymerase chain reaction (PCR) in the detection of Leishmania DNA in archived Giemsa-stained bone marrow slides for diagnosis of visceral leishmaniasis (VL), and to compare PCR with conventional diagnostic techniques, like direct microscopy and parasite culture. Specimens of archived Giemsa-stained bone marrow slides from 91 patients with VL and from 79 controls with other diseases or conditions were studied. PCR showed the highest sensitivity (92.3%) and had good specificity (97.5%). Direct examination detected 79.1% and culture 59% of positive samples. In addition, PCR was able to detect VL in 16 of 19 patients (84.2%) with negative microscopy. PCR in Giemsa-stained bone marrow slides is a suitable tool for confirming diagnosis in patients with VL and may be useful in the diagnosis of difficult cases. Slide smears are easily stored, do not require special storage conditions such as low temperatures, and can be easily mailed to centers where PCR is available, making it an excellent option for diagnosis in the field.

Polymerase chain reaction of peripheral blood as a tool for the diagnosis of visceral leishmaniasis in children

The diagnosis of visceral leishmaniasis (VL) generally requires the use of invasive tests for the collection of infected tissue (aspirates of bone marrow, spleen, liver or lymph nodes). This difficulty has led to the search for safer and less painful techniques to confirm the occurrence of the disease in children. Polymerase chain reaction (PCR) is a method that is advantageous in that it allows the use of peripheral blood samples for diagnosis. This paper reports the utilisation of PCR on peripheral blood samples to diagnose VL in 45 children in Mato Grosso do Sul, Brazil. This technique is compared with methods carried out using tissue collected by invasive procedures, including direct microscopy, culture and detection of Leishmania DNA by PCR in bone marrow aspirates. The results show that PCR of peripheral blood provides great sensitivity (95.6%) that is similar to that from the PCR of bone marrow aspirates (91.1%) and higher than that achieved with microscopy (80%) or culture (26.7%) methods. PCR of peripheral blood proved to be a suitable tool for the diagnosis of VL in children because it is highly sensitive and safe, with tissue collection being less invasive than in traditional tests.

Severe adverse reactions to meglumine antimoniate in the treatment of visceral leishmaniasis: a report of 13 cases in the southwestern region of Brazil

Antimony-based medications continue to be the chosen drug for visceral leishmaniasis treatment in most countries. Pentavalent antimony compounds are highly effective but frequently have adverse reactions. Although toxic effects are almost always reversible, some of them can be severe. Clinical and laboratory data of 13 patients who developed severe adverse reactions to meglumine antimoniate in a teaching hospital in southwestern Brazil in 2004–2005 were analysed. Most patients were adults (10/13), mainly at the age of 50 or older (4/13). The main severe adverse reactions were renal failure (eight episodes), pancreatitis (six episodes) and hepatic failure/hepatitis (five episodes). Six patients died in the period; all presented acute renal failure and four presented hepatic failure. Meglumine antimoniate can cause severe reactions, which can lead to death if not promptly identified. Further studies are warrented on the effect of less toxic drugs.

Treatment of visceral leishmaniasis in children in the Central-West Region of Brazil

BackgroundDetailed reports on the treatment of visceral leishmaniasis (VL) are scarce, particularly with regard to the utilization of antimoniate of N-methylglucamine. The aim of this study was to analyze the treatment of children admitted to a reference hospital, focusing in particular on the use of antimoniate of N-methylglucamine and on the supportive measures adopted.Materials and methodsMedical records of children treated for VL from January 1998 to February 2005 in the Hospital of the University of Mato Grosso do Sul, Central-West Region of Brazil, were reviewed retrospectively.ResultsA total of 116 children were treated, and 111 received antimoniate as the first therapeutic choice. The drug was highly efficient (96.9%) in patients with no signs of gravity on admission, in cases presenting warning signs of potential evolution to gravity, and even in some severely ill children. The most common adverse effects were increases in transaminase (22.5%) and amylase (17.5%) levels, and generally reversible electrocardiogram changes (18%). Some problems were detected during the treatment, such as inadequate prescription (causing an under- or overdose) or inappropriate change to a second-line scheme. Of the 116 children, 80% were given antibiotics, 71.5% needed a transfusion of red blood cells, 10.3% required a transfusion of platelets, fresh frozen plasma was given to 4.3%, albumin was administered in 3.4, and 8.6% needed intensive care support. The mortality rate was about 2.6%.ConclusionAntimoniate of N-methylglucamine remains highly efficient and well tolerated in pediatric patients, which allows its utilization as a first-line therapy in Brazilian children until a better drug for widespread use becomes available; however, it should be used with caution, and special attention is required during its prescription and for the management of adverse effects. The low mortality rate obtained confirms that, in addition, successful treatment demands the correction of serious anemia and thrombocytopenia, the vigorous use of antibiotics to fight intercurrent bacterial infections, and sometimes the availability of intensive care units to treat more severe patients.

Comparison of conventional methods for diagnosis of visceral leishmaniasis in children of the Center-West Region of Brazil

In Brazil, sophisticated techniques currently employed for diagnosis of visceral leishmaniasis, such as polymerase chain reaction-based assays, are only available in major research centers, whereas conventional methods are still used in many areas where the disease occurs. In the state of Mato Grosso do Sul, in the countrys Center-West Region, visceral leishmaniasis has recently emerged in many cities, and duration of the disease, from the onset of symptoms to diagnosis, has been short. Considering that results of diagnostic tests may depend on the phase of the disease, we compared direct examination of bone marrow aspirates (BMAs), BMA culture, and serology by Indirect Immunofluorescence Antibody Test (IFAT) for diagnosis in children, according to time of evolution (< or = 30 days or > 30 days) and to spleen size (< or = 5 cm or > 5 cm) at admission. Duration of the illness did not interfere with test positivity: direct smear examination and IFAT were positive in more than 80% of patients, as was culture in around 60%. Results of positive microscopy, however, where predominant in patients with larger spleens. Thanks to the association of traditional techniques, only a few patients had to begin a treatment trial without confirming the diagnosis. Conventional methods for diagnosis of visceral leishmaniasis are still indispensable in our region, and training professionals in basic techniques should be incremented. The highest sensitivity in laboratory diagnosis among the cases investigated was that obtained with a combination of BMA direct examination and IFAT, nearing 100%.

Pertussis in the central-west region of Brazil: one decade study

In many parts of the world, numerous outbreaks of pertussis have been described despite high vaccination coverage. In this article we report the epidemiological characteristics of pertussis in Brazil using a Surveillance Worksheet. Secondary data of pertussis case investigations reported from January 1999 to December 2008 recorded in the Information System for Notifiable Diseases (SINAN) and the Central Laboratory for Public Health (LACEN-MS) were utilized. The total of 561 suspected cases were reported and 238 (42.4%) of these were confirmed, mainly in children under six months (61.8%) and with incomplete immunization (56.3%). Two outbreaks were detected. Mortality rate ranged from 2.56% to 11.11%. The occurrence of outbreaks and the poor performance of cultures for confirming diagnosis are problems which need to be addressed. High vaccination coverage is certainly a good strategy to reduce the number of cases and to reduce the impact of the disease in children younger than six months.

Difficulties in Diagnosis of Malaria in Non-Endemic Areas: A Case Report ofa Child in Brazil

Malaria is a tropical parasitic disease that triggers severe social and economic problems worldwide and causes thousands of deaths each year. Early diagnosis enables proper treatment. People from non-endemic areas who travel to areas of transmission are often exposed to late or incorrect diagnosis because healthcare professionals have great difficulty in conceiving malaria as a diagnostic hypothesis. In addition, technicians skilled in recognizing malaria etiologic agent are not abundant. This paper addresses the case of a child from a non-endemic malaria region in Brazil, with a prior hypothetic diagnosis of visceral leishmaniasis, however bone marrow aspirate revealed Plasmodium instead of Leishmania. A retrospective epidemiological investigation showed a history of a recent trip to a malaria area and the review of blood smears obtained on admission disclosed a large number of trophozoites and gametocytes of Plasmodium falciparum that had been unnoticed, suggesting that diagnosis could have been possible earlier. Malaria clinical picture is easily mistaken for other febrile infectious diseases, thus the possibility of its occurrence cannot be ruled out. There is a need to increasingly train the microscopy technicians, both in endemic and non-endemic areas, so as to minimize the false diagnoses and decrease morbidity and mortality of the disease.