The effect of palm oil addition to the diet of dairy sheep on the immune response.

The aim of this study was to evaluate whether a diet based on palm oil has any influence on the immune response and on the number of eggs per gram of faeces (EPG) of gastrointestinal nematodes (GIN) in dairy sheep. To address this issue, 30 ewes in early lactation were confined and divided into three groups (n = 10) receiving a daily isoproteic and isoenergetic diet. Palm oil was added to the feed at different concentrations: 0% (control; group A), 4% (group B) and 6% (group C). The animals were treated with levamisole 10 days before the beginning of the experiment. Faecal samples were collected and analysed for EPG on day zero of the experiment. On days 60 and 120, individual faecal and blood samples were collected, and the FAMACHA(©) score for assessing clinical anaemia was carried out. The groups receiving palm oil showed a significant reduction in EPG in relation to the control group (A) on day 120. Serum immunoglobulin levels (IgG, IgM and IgE) and proinflammatory cytokine levels (TNF-α, IL-1 and IL-6) were significantly increased on days 60 and 120 (p < 0.05) in groups B and C. Therefore, these results suggest that palm oil stimulates the immune response in sheep, thus reducing EPG of GIN. The hypothesis that palm oil has direct anthelmintic activity should be tested in future studies.

Healthcare-associated infections: a threat to the survival of patients with COVID-19 in intensive care units.

BACKGROUND: Wide variation in mortality rates among critically ill patients with coronavirus disease 2019 (COVID-19) has been reported. This study evaluated whether healthcare-associated infections (HAI) are a risk factor for death among patients with severe COVID-19 in the intensive care unit (ICU). METHODS: This retrospective cohort study included patients with severe COVID-19 hospitalized in the ICU of four hospitals in the city of Curitiba, Brazil. Patients with COVID-19 who died during ICU hospitalization were compared with those who were discharged. A second analysis compared patients who developed HAI in the ICU with those who did not. Multiple logistic regression models were used to control for confounders. RESULTS: In total, 400 patients were included, and 123 (31%) patients developed HAI. The most common HAI was lower respiratory tract infection (67%). Independent risk factors for death were: age [odds ratio (OR) 1.75, 95% confidence interval (CI) 1.43-2.15; P<0.0001]; clinical severity score (OR 2.21, 95% CI 1.70-2.87; P<0.0001); renal replacement therapy (OR 12.8, 95% CI 5.78-28.6; P<0.0001); and HAI (OR 5.9, 95% CI 3.31-10.5; P<0.0001). A longer interval between symptom onset and hospital admission was protective against death (OR 0.93, 95% CI 0.88-0.98; P=0.017). The only independent factors associated with HAI were high C-reactive protein and low PaO2/FiO2 ratio. CONCLUSIONS: No factors that could point to a high-risk group for HAI acquisition were identified. However, age, dialysis and HAI increased the risk of death in ICU patients with severe COVID-19; of these, HAI is the only preventable risk factor.

Acquired cell-mediated immunodepression in acute Chagas' disease.

In this study two groups of patients with acute Chagas' disease were identified. Group one consisted of five patients with apparent acute Chagas' disease. These patients showed symptoms and signals of an acute illness, such as high fever and enlarged spleen. One of these patients developed severe myocarditis and heart failure. Group two consisted of seven patients with inapparent acute Chagas' disease. This was a nonclinical entity, not perceived by the patient who did not seek medical care. The diagnosis was made by the shift of a serologic test which indicates the presence of immunoglobulin M antibodies to Trypanosoma cruzi. The patients with apparent acute Chagas' disease showed positive delayed-type skin response to T. cruzi antigen. Also, their leukocytes showed significant inhibition of migration in the presence of this antigen. By contrast, the patients with the inapparent acute Chagas' disease did not show positive delayed-type skin response to T. cruzi antigen and no significant inhibition was observed when their cells migrated in the presence of this antigen. Of interest, none of these patients was capable of developing contact sensitivity to 2,4-dinitrochlorobenzene. However, three out of five patients with the apparent acute disease and all the normal control subjects showed positive contact reaction after sensitization to this drug. The results of these experiments would suggest that the thymus-derived (T)-lymphocyte function is depressed in patients with the clinically inapparent acute Chagas' disease. This immunodepression seems to be acquired in the course of the T. cruzi infection because all patients showed positive delayed-type skin response to at least one ubiquitous microbial extract, thus indicating previously normal T-cell function. We hypothesize that T. cruzi antigens may directly stimulate T cells with the concomitant release of factors that might become supressive for T-cell responses. Furthermore, the suppressive effect might interfere with the T-cell response to other antigens, such as to 2,4-dinitrochlorobenzene.

Chagas' disease: a clinical, parasitological, immunological, and pathological study in rabbits.

Thirty-four rabbits were experimentally infected with trypomastigotes of either the Ernestina or the Albuquerque strains of Trypanosoma cruzi. These animals showed patent parasitemias, as demonstrated by xenodiagnosis, in the acute phases of the infections. Typical chagoma signs developed in two rabbits 1 week after parasite inoculation in the skin, although the acute phase of Chagas' disease in the rabbit model was usually asymptomatic. In the 6th month of infection the parasitemias became negative and the infections remained subpatent, as indicated by the persistence of positive serologic tests and of delayed-type skin reactions elicited in Chagas' rabbits against a microsomal T. cruzi antigen. This latent infection continued asymptomatically, in the absence of electrocardiographic (ECG) alterations. However, ECG changes consistent with enlargement and overload of cardiac chambers, alterations of ventricular repolarization, S-T changes and bundle-branch blocks were frequently recorded later in the chronic phase of Chagas' disease. The pathological manifestations of these ECG alterations were confirmed at the autopsy of each experimental rabbit. Congestive heart failure and pulmonary thromboemboli related to chronic myocarditis of Chagas' disease were frequent causes of death. Megacolon was seen in two rabbits inoculated with the Ernestina strain of the parasite. The relatively limited duration of detectable parasitemia even when xenodiagnosis is used, the lack of correlation between parasitemia and severity of pathological manifestations, and the fact that all infected animals showed histopathological evidence of myocarditis, destructive inflammatory lesions characterized by mononuclear infiltrates in skeletal muscles, as well as cutaneous delayed hypersensitivity to T. cruzi antigens, are notable observations in this animal model of the human disease.

Trypanosoma cruzi-sensitized T-lymphocyte mediated 51CR release from human heart cells in Chagas' disease.

Cytotoxicity of T-lymphocytes from patients with Chagas' disease to parasitized and non-parasitized human heart cells labelled with 51Cr was demonstrated. The highest ratio of 51Cr released from the normal, non-parasitized heart cells was observed when the T-lymphocytes were collected from patients with acute Chagas' disease. The quantity of 51Cr released from the normal heart cells that were destroyed by T-lymphocytes collected from patients with chronic Chagas' disease was also significantly higher than the quantity of 51Cr released from normal heart cells incubated with lymphocytes from normal donors. The specific release of 51Cr from the heart cell cultures destroyed by the immune T-lymphocytes from patients with acute Chagas' disease and from patients with chronic disease was 38.1% and 25.8%, respectively, compared to the release of 51Cr observed in control studies. A small particle human heart cell antigen was shown to inhibit the migration of Trypanosoma cruzi-immune peripheral blood leukocytes. The findings appear to indicate that T-lymphocytes from patients with Chagas' disease are susceptible to activation by a cross-reactive heart cell antigen and suggest that an autoimmune mechanism can be established in some cases of acute Chagas' disease and can be perpetuated in the chronic phase of this disease by the continuous antigenic stimulation. Further, these experimental data indicate that the autoimmune destruction of heart cells in Chagas' disease is produced by delayed-type hypersensitivity mediated by T. cruzi-sensitized T-lymphocytes.

Comparison of cutaneous leishmaniasis due to Leishmania (Viannia) braziliensis and L. (V.) guyanensis in Brazil: therapeutic response to meglumine antimoniate.

We conducted a quasi-experimental study to compare the response to meglumine antimoniate in patients with localized cutaneous leishmaniasis from two endemic areas of Brazil that were infected by two Leishmania species. Sixty-one were infected by Leishmania (Viannia) braziliensis (group B) and 57 by L. (V.) guyanensis (group G). All had a parasitologically proven diagnosis and were treated with 20 mg of pentavalent antimonial (SbV)/kg/day given intravenously or intramuscularly for 20 days. Main outcomes were diagnosed using clinical criteria three months after treatment and patients were followed for six months. Intention-to-treat analysis showed a higher failure rate in group G (relative risk [RR] = 1.5, 95% confidence interval [CI] = 1.1-2.0, chi2 = 7.44, P = 0.006). The analysis using an explanatory approach including 52 patients from group B and 49 from group G, who were regularly treated and followed for six months, showed a low cure rate (50.8% in group B and 26.3% in group G) with a greater risk of failure in the latter group (RR = 1.7, 95% CI = 1.2-2.5, chi2 = 8.56, P = 0.003). The effect of the etiologic agent remained significant after adjusting for age, disease duration, and site and number of lesions that were identified as predictors of failure in a logistic regression model. We concluded that Leishmania species constitute an important factor in predicting the outcome of cutaneous leishmaniasis treated with a pentavalent antimonial.

Clinical observations of unresponsive mucosal leishmaniasis.

We report the long-term clinical follow-up of two patients with unresponsive mucosal leishmaniasis due to Leishmania (Viannia) braziliensis from the Três Braços area in Bahia State, Brazil. Both were agricultural male workers with extensive upper respiratory mucosal involvement that was not cured with conventional and experimental therapy.

Serum albumin and gamma globulin in Trypanosoma cruzi infections.

This paper examines the association between serum protein levels and infection with Trypanosoma cruzi in a region of Central Brazil. 148 people 6 to 78 years of age, were included in this study. There were no statistically significant difference in albumin levels between those with positive T. cruzi serology (2.94 +/- 0.74 g/100 ml) and those with negative serology (3.04 +/- 0.61 g/100 ml). Thus the null hypothesis of no association between infection with T. cruzi and serum albumin is accepted. Gamma-globulin levels were elevated in both groups and were significantly greater (p less than 0.05) in the group with positive T. cruzi serology (1.91 +/- 0.41 g/100 ml) than in the group with negative serology (1.75 +/- 0.41 g/100 ml). The serum albumin levels suggest that malnutrition (either associated with low protein intake or increased loss due to hookworm) is a major problem and unlikely to change if T. cruzi transmission was controlled.

Dipetalogaster maximus (Hemiptera, Triatominae) for xenodiagnosis of patients with serologically detectable Trypanosoma cruzi infection.

In patients serologically positive for Trypanosoma cruzi infection the three bug species/instar combinations used in xenodiagnosis showed third-instar Dipetalogaster maximus to be more efficient in detecting circulating trypanosomes than the first instar of the same species which, in turn, is more sensitive than third-instar Triatoma infestans. The sensitivity of the pool technique of faecal examination compared with individual dissection was investigated. Four pool examinations (the product of 20 bugs) were equivalent to 10 individual bug dissections. Because of the ease of providing large numbers of bugs for mass xenodiagnosis, first-instar D. maximus has replaced third-instar T. infestans in our routine work. The value of third-instar D. maximus as a xenodiagnostic agent needs further investigation.

Sensitivity of the polymerase chain reaction for the diagnosis of cutaneous leishmaniasis due to Leishmania (Viannia) guyanensis.

The sensitivity of the polymerase chain reaction (PCR) in 35 consecutive outpatients with cutaneous leishmaniasis caused by Leishmania (Viannia) guyanensis was evaluated using, as gold standard, the in vitro isolation of the parasite through culture of aspirates of the cutaneous ulcers. All isolates were identified using electrophoretic enzyme analysis. Patients were mainly young males with recent onset disease without prior specific treatment. PCR was performed using DNA extracted from fresh frozen biopsies of cutaneous ulcers. The reaction used a pair of oligonucleotides that amplify the conserved region of the minicircle molecule. PCR showed 100% sensitivity (95% CI from 90.0 to 100.0). These results were similar to the visualization of amastigotes in imprint preparations of cutaneous biopsy tissue and the inoculation of biopsy material in golden hamsters. Despite the high sensitivity of the PCR, in this particular clinical setting of cutaneous leishmaniasis caused by L. (V.) guyanensis in the Brazilian Amazon, it appears that the method of choice for diagnosis should be the direct visualization of amastigotes using imprint preparations and the PCR reserved for those patients with negative imprint results.

[Musculocutaneous and visceral cysticercosis: a rare disease?]. / Cisticercose músculo-cutânea e visceral--doença rara?

The aims of the present study were to measure the frequency of cutaneous, muscular and visceral forms of cysticercosis in anatomopathological examinations and necropsies in the Federal District and to study the clinical aspects of this disease. In 64.911 protocols of anatomopathological examinations reviewed, 30 (0.05%) had the diagnosis of cysticercosis, 90% had cysticerci in the subcutaneous tissue, skeletal muscle or mucous membrane, 3.3% in lymph node and 6.7% in the central nervous system. Two (7.4%) patients had cysticerci in the tongue. In 1520 autopsies protocols reviewed, 25 (1.6%) autopsies with cysticercosis were found. 96% had cysticerci in the central nervous system, 8% in the heart, 8% in the skeletal muscle and 4% in the liver, either isolated or associated with cysticerci in other viscera. 1122 people were also examined. Indirect immunofluorescence and ELISA were the serological tests used in all patients for the diagnosis of cysticercosis. The radiological investigation of the skull and soft tissues was also performed. 59 (5.3%) patients had both serological tests positive (10 had also biopsies with the diagnosis of cysticercosis). The muscular form was found in 42.4%, subcutaneous cysts were present in 20.3% and the visceral form was found in 3.4% of cases. In patients with visceral cysticercosis, the cysts were localized in the heart, pleura, kidney and ovary. Calcifications in the skull and/or soft tissues were demonstrated radiologically in 32 (2.8%) patients with negative serological tests for cysticercosis. The present study suggests a high frequency of subcutaneous and muscular forms of cysticercosis in the Federal District. The visceral form of the disease is also found in various organs, without clinical manifestations of importance.

[The behavior of Trypanosoma cruzi parasitemia in chronic chagasics over 13 years]. / Comportamento da parasitemia pelo Trypanosoma cruzi em chagásicos crônicos durante 13 anos.

The parasitemia of 202 chronic chagasics was studied for approximately 13 years by repeated conventional xenodiagnoses. Mean patient age was 41.1 years. They lived in an endemic area; 124 were females and 78 were males. It was seen that the level of parasitemia oscillated. It went up in 14 individuals, went down in 42 and stayed at the same level in 146. In general the parasitemia was reduced. The percentage of xenopositive chagasics, which was 37.6%, 48.5%, and 51% in the first, second and third xenodiagnosis, respectively, in 1976/78, changed to 30.2% in 1988/91 (p = 0.00003). The percentage of positive pools, which was 15.2%, 20.9%, 20.8% in the first, second and third xenodiagnosis, respectively, in 1976/78, changed to 10.4% in 1988/91, (p = 0.00000001). There were 62 patients whose xenodiagnoses were all negative and 23 whose exams were all positive. The percentage of chagasics with high, medium and low parasitemia, which in 1976/78 was 9.4%, 20.8% and 69.8%, respectively, changed to 4.4%, 12.9% and 82.7%, respectively, in 1988/91.

[A 13-year clinical study on 190 chronic chagasic patients from Mambaí, Goiás, Brazil]. / Estudo clínico durante 13 anos de 190 chagásicos crônicos de Mambaí, Goiás, Brasil.

A prospective study was performed on the clinical, electrocardiographic (ECG) and radiologic aspects of the esophagus in 190 chagasic patients, for on average follow-up period of 13 years. We found 108 (56.8%) patients who remained in the same clinical state, 72 (37.9%) patients with progressive illness and 10 (5.3%) patients whose previous ECG abnormalities subsided. Thirty nine out of 72 patients with progressive disease developed cardiopathy or aggravation of previous illness, 32 developed into megaesophagus or an existing picture deteriorated and 12 developed or showed worsening of the colopathy. Of 72 patients, 11 presented with associated forms. The development of cardiopathy was greater in males 29.6% (21/71) than in females 15.1% (18/119), p =0.015. There were 19 new cases of cardiopathy, and 20 of aggravated previous disease. The incidence of megaesophagus was 14.9% (23/154), with nine patients whose previous disease worsened. The progression of colopathy was greater in females 9.2% (11/119) than in males 1.4% (1/71), p = 0.026.

[Measurement of the volume of the skin ulcer in cutaneous leishmaniasis]. / Medida do volume da úlcera cutânea na leishmaniose tegumentar.

Skin ulcers by Leishmania (Viannia) braziliensis are often deep and irregular and are difficult to measure by just the skin surface transverse and longitudinal diameters. The proposal is to mould the cavity, after local asepsis with fresh water plus soap, with a gelatinous plastic which contains silence, potassium alginate, calcium sulphate, magnesium oxide commercialized under the name of jeltrate (Dentsply Laboratory), by solving 9.5g of jeltrate in 20ml of fresh water and applying the gel on the ulcer which solidifies in 5 minutes. This mould is then filled with a self polymerising acrylic and its volume measured either by weight (by using an analytical balance)-technique 1-or by water displacement by applying Archimeds'principle-technique 2. We show data in a field trial before and after 20 days treatment in 20 patients using three different schedules as follows: 7 received pentamidine isethionate, 7 patients received aminosidine sulphate and 6 received meglumine antimoniate. The results point out that there was a uniform reduction of ulcer volume occurred during this period in the three groups, in both technique. Regarding the therapeutic schedules we are sure that there was a significant statistical difference between the three schedules using the T Student Test, which showed that aminostdine sulphate produced a better volume reduction of the ulcer than the other drugs. Serial moulds reflect clinical billing and are a permanent record. We conclude that the measure of the volume of the skin ulceration can be useful in the therapeutic evaluation, as a practical and cheap procedure, and may be used in field trials.

Plasmodium vivax resistance to chloroquine (R2) and mefloquine (R3) in Brazilian Amazon region.

We report for the first time a patient with malaria due to Plasmodium vivax who showed R2 resistance to chloroquine and R3 resistance to mefloquine in the Brazilian Amazon region based on WHO clinical criteria for diagnosis of malaria resistance. Failure was observed with unsupervised oral chloroquine, chloroquine under rigorous supervision and mefloquine in the same scheme. Finally, the patient was cured with oral artesunate.

[A longitudinal radiologic study of the esophagus in an endemic area of Chagas' disease over a 6-year period]. / Estudo radiológico longitudinal do esôfago, em área endêmica de doença de Chagas, em um período de seis anos.

A longitudinal study over six years was undertaken of 494 residents of the municipality of Mambaí, Goiás. Two hundred and twelve (43%) were seropositive in 1975/76 and 199 of 464 of the same patients group, positive in 1980/82 (42.8%). At both examination single radiographs of the oesophagus were obtained immediately after ingestion of 75 ml of barium sulphate solution and a second X-ray taken one minute later. Among the 201 seropositive patients without megaesophagus in the first study 4 (2%) evolved megaesophagus during the six years of observation. During this time, using Rezende's classification, patients with established megaesophagus, changed their group in the following manner. Only one Group I patient changed to group II. Only one group II patient progressed to group IV. Progress of megaesophagus in the affected patients occurred in 2.8% of 212 patients. Also four patients with grade I megaesophagus initially had a normal oesophagogram on the follow up examination. Ten patients had doubtful oesophagogram initially and six on follow up, 75% of these patients were seropositive. This study could indicate that a doubtful oesophagogram is an early sign of megaoesophagus.

[Longitudinal radiologic study of the esophagus, in an endemic area of Chagas disease, in a period of 13 years]. / Estudo radiológico longitudinal do esôfago, em área endêmica de doença de Chagas, em um período de 13 anos.

A radiological study of the oesophagus of a cohort of patients was carried during a 13 year period in the municipality of Mambaí Goiás. Barium swallow findings were recorded on 70mm film using a portable machine. Of 731 patients examined 382 (52.3%) were seropositive for T. cruzi. The sexes were equally divided. The incidence of detectable megaoesophagus was 7.9% among the cohort and 14.2% in the seropositive individuals. Progression of the disease was noted during this longitudinal study in 21.7% of males and 16.6% of females.

[Clinical study of falciparum malaria in children in Manaus, AM, Brazil]. / Estudo clínico da malária falciparum em crianças em Manaus, AM, Brasil.

The clinical characteristics of falciparum malaria were studied among 61 children, aged 0 to 14 treated at a reference center in Manaus, from October to December 1997. The symptoms observed were fever (98.4%), headache (80.3%), chills (68.9%), perspiration (65. 6%), myalgia (59.0%), nausea (54.1%), lumbar pain (49.2%), vomiting (49.2%), cough (45.9%), arthralgia (31.1%), diarrhea (34.4%), dyspnea (8.2%), convulsions (8.2%) and dizziness (4.9%). Pallor and anaemia were found more frequently in children under five years old. Anaemia was associated with high levels of parasitaemia. Fifty-eight (91.5%) patients had uncomplicated malaria, 3 (4.9%) had severe malaria and the lethality was 1.6%.

[RIII mefloquine resistance in children with falciparum malaria in Manaus, AM, Brazil]. / Resistência à mefloquina do tipo RIII em crianças com malária falciparum em Manaus, AM, Brasil.

We report the occurrence of resistance to mefloquine 20mg/day in 51 children with falciparum malaria treated, at reference center of Manaus, Brazil, from October to December 1997. All children were evaluated at day 3, 5, 7, 14, 21, 28 and 35 of treatment. Clinical and parasitological cure criteria were adopted. The incidence of RIII mefloquine resistance was 5.9% (IC 95% 1.5-17.2). The cure/resistance proportion was 20:1 and cure/severity was 62:1. These findings suggest the importance of mefloquine resistance within this group of children.

[Anisocoria in the chronic phase of Chagas' disease]. / Anisocoria na fase crônica da doença de Chagas.

To compare the frequency of anisocoria in patients with chronic Chagas' disease a prospective double-blind study was done in 131 patients with positive serology for Chagas' disease and 138 negative, at Mambaí (GO-Brazil), which is an endemic area for Chagas' disease. To detect anisocoria, pupillometry was done with a millimetric ruler. Anisocoria was seen in 10(7.6%) patients with Chagas' disease and in 3(2.1%) normal subjects. The chi-square test showed statistical significance at level of 5%. Chagas' disease must be included among the causes of anisocoria.