Poster No. 106 Can we optimize d-dimer cut off value to predict pulmonary embolism in covid-19 patients?

Background

Covid-19 is associated with an increased risk of pulmonary embolism (PE) therefore, should the cut off d-dimer value be adjusted for these patients?

Material and methods

Retrospective and observational study to understand if there is a d-dimer cut-off that could guide clinics to perform a thoracic computed tomography angiography (CTA) in patients with covid-19. The population was covid-19 patients admitted to covid-19 dedicated wards of a University Hospital Centre for one year.

Results and conclusions

725 (52%) patients with covid-19 had a d-dimer value dosed during the first 5 days of the disease. Those, 63 (9%) did a CTA with a diagnosis of 16 (25%) PE. Gender was equally represented, median age was 70 years (ID = 3.49) and the majority (94%) survived. Thirteen (81%) patients with PE had a d-dimer value above 2500 ng/mL (OR = 9.244, 95% CI 2.248–9.837), with 7 (54%) with values over 10000 ng/mL, but in 3 (9%) it was under 1500 ng/mL. Seventy-three (63%) of patients with a d-dimer over 1500 ng/mL did not had a thoracic CTA performed. In our population PE was not a frequent outcome. The results are influenced by the low number of thoracic CTA performed because, even tough the cut-off d-dimer value used at our hospital to perform a thoracic CTA to exclude PE is 1500 ng/mL, most patients with that d-dimer value did not take the exam and so PE could not be excluded. Although in most PE cases the d-dimer value was above 2500 ng/mL, the results of our study cannot verify if that is a better cut-off value.

Can carotid angioplasty stenting be better than endarterectomy or best medical treatment for patients with carotid stenosis?

Background

Carotid stenosis is responsible for a considerable amount of strokes and related deaths. Carotid angioplasty stenting (CAS), endarterectomy (CEA) and best medical treatment (BMT) are important in preventing major cardiovascular (CV) events.

Methods

We conducted a systematic review and meta-analysis, with randomized controlled trials (RCT), to compare CAS with CEA and BMT regarding the short and long-term major periprocedural and follow-up CV events (stroke, myocardial infarction, and death) in symptomatic and asymptomatic carotid stenosis. We searched for RCT published from 2008 to 2021 in databases such as Pubmed/MEDLINE, B-On, Embase, Clinical Trials from U.S. National Library of Medicine and International Clinical Trials Registry Platform, between July of 2018 and January of 2019, and in October of 2021.

Results

Nine RCT were included, with a total of 9162 participants for CAS versus (vs) CEA, and 513 participants for CAS vs TMO. Compared with CEA, CAS is associated with periprocedural stroke and death in symptomatic patients (HR=1.65, 95% CI: 1.29–2.11, p=0.05, I2=62%), due to higher stroke events than deaths. That association does not occur in asymptomatic patients in which CAS is not associated with periprocedural stroke or death (CAS=8.55%, CEA=7.05%, p=0.09). During follow-up there were no significant differences between CAS and CEA in symptomatic patients regarding stroke (HR=1.51, 95% CI: 1.23–1.84, p=0.57, I2=0%) and death (HR=1.10, 95% CI: 0.93–1.30, p=0.69, I2=0%). Periprocedural myocardial infarction (MI) incidence is higher in CEA (CAS=1.1%; CEA=2.3%; p=0.03), without influence of symptomatic status. CAS is not inferior to CEA, in both symptomatic and asymptomatic patients with high surgery risk, as for periprocedural and one year CV major events (CAS=12.2%, CEA=20.1%, absolute difference = −7.9, 95% CI: −16.4–0.7, p=0.004). BMT had no significant findings vs CAS in asymptomatic patients (HR=3.5, 95% CI: 0.42–29.11, p=0.246).

Conclusion

CAS is not inferior to CEA as for the periprocedural and one-year major CV events in patients with normal surgery risk. However, there is a higher risk of periprocedural stroke in CAS for symptomatic patients, and of periprocedural MI in CEA with no influence of symptomatic status. CAS seams to prevent middle and long-term ipsilateral stroke in symptomatic patients. BMT has yet to prove not to be inferior to CAS in asymptomatic patients.

Funding Acknowledgement

Type of funding sources: None.

Prognostic Value of Isolated Elevated Troponin I Levels in Patients without Acute Coronary Syndrome Admitted to the Emergency Department

Fundamento:

Embora a elevação não isquêmica da troponina seja frequentemente observada em pacientes admitidos no pronto-socorro (PS), não há consenso quanto ao seu manejo.

Objetivos:

Este estudo teve como objetivo caracterizar os pacientes admitidos no PS com elevação da troponina não-isquêmica e identificar potenciais preditores de mortalidade nessa população.

Métodos:

Este estudo observacional retrospectivo incluiu pacientes do PS com resultado positivo no teste da troponina entre junho e julho de 2015. Pacientes com diagnóstico clínico de síndrome coronariana aguda (SCA) foram excluídos. Os dados demográficos dos pacientes e as variáveis clínicas e laboratoriais foram extraídos dos prontuários médicos. Os dados do seguimento foram obtidos por 16 meses ou até a ocorrência de morte. O nível de significância estatística foi de 5%.

Resultados:

A elevação da troponina sem SCA foi encontrada em 153 pacientes no PS. A mediana (IIQ) de idade dos pacientes foi de 78 (19) anos, 80 (52,3%) eram do sexo feminino e 59 (38,6%) morreram durante o seguimento. A mediana do período de seguimento (IIQ) foi de 477 (316) dias. Os sobreviventes eram significativamente mais jovens 76 (24) vs. 84 (13) anos; p=0,004) e apresentaram uma maior proporção de elevação da troponina isolada (sem elevação da creatina quinase ou mioglobina) em duas avaliações consecutivas: 48 (53,9%) vs. 8 (17,4%), p<0,001. Os sobreviventes também apresentaram menor taxa de tratamento antiplaquetário e internação no mesmo dia. Na regressão logística multivariada com ajuste para variáveis significativas na análise univariada, a elevação isolada da troponina em duas avaliações consecutivas mostrou hazard ratio = 0,43 (IC95% 0,17–0,96, p=0,039); hospitalização, tratamento antiplaquetário anterior e idade permaneceram independentemente associados à mortalidade.

Conclusões:

A elevação isolada da troponina em duas medidas consecutivas foi um forte preditor de sobrevida em pacientes no PS com elevação da troponina, mas sem SCA.

Circulating Biomarkers of Collagen Metabolism and Prognosis of Heart Failure with Reduced or Mid-Range Ejection Fraction

BACKGROUND

Change in the architecture and composition of cardiac extracellular matrix is a key element in adverse cardiac remodeling that occurs during heart failure. Most of the times, the result is the development of fibrosis, which has a huge impact on the pathophysiology and clinical outcomes of heart failure syndromes. Several molecules related to collagen metabolism detectable in the blood have been proposed as biomarkers of myocardial fibrosis. Despite concerns regarding the true ability of these biomarkers to reflect quantitative and qualitative changes in myocardial collagen, a growing body of evidence suggests that they may play a potential role in several aspects of heart failure management.

METHODS

This review aimed to summarize published data regarding the role of circulating biomarkers of collagen metabolism in the assessment of prognosis in patients with heart failure with reduced or mid-range LVEF ventricular ejection fraction (LVEF < 40% or LVEF 40-49%, respectively). Medline electronic database was searched to identify relevant studies published through October 2016.

RESULTS

Most evidence regarding the prognostic value of collagen biomarkers in HF with reduced or mid-range LVEF lies on data concerning PIIINP and several MMPs and TIMP-1. Several prospective studies found that higher levels of PIIINP, several MMPs and TIMP-1 are associated with higher rates of mortality and/or HF hospital admissions in HF patients with LVEF < 50%.

CONCLUSION

Circulating collagen biomarkers have been shown to play a role in prognostic stratification in heart failure patients with reduced or mid-range ejection fraction.

Fractional flow reserve of non-culprit vessel post-myocardial infarction: is it reliable?

Background

Multi-vessel disease is frequent in patients presenting with myocardial infarction and have an important prognostic impact. The decision to proceed to revascularization in non-culprit vessels can be postponed until ischemia is proven in non-invasive stress tests. On the other hand, there is an increasing evidence to support the role of fractional flow reserve (FFR) in acute coronary syndrome setting.

Case presentation

We report a case in which a FFR-guided strategy for non-culprit vessels, 3 weeks after an ST-segment elevation myocardial infarction, was followed by a short-term sub-occlusion of the evaluated vessel.

Conclusion

The timing of the coronary microcirculation recovery post-myocardial infarction, avoiding a possible false negative FFR, and the diagnostic gaps between ischemia and plaque vulnerability are under discussion. An FFR-guided strategy in this setting should be interpreted with caution.

Potential distribution and cost estimation of the damage caused by Cryptotermes brevis (Isoptera: Kalotermitidae) in the Azores

In the Azores archipelago, a significant proportion of buildings are infested with the urban exotic drywood termite Cryptotermes brevis (Walker), causing major economical and patrimonial losses. This work aims to understand the potential spread of this termite species in the Azores and estimate the costs for both treatment and reconstruction of infested buildings in the entire archipelago. A maximum entropy niche modeling process was used to determine the potential occurrence of the species on each island. Different scenarios were built using independent global and regional incidence and environmental data. Both projections reveal the same pattern. Generally, the probability of occurrence is higher near the coast line, where, in Azores, the majority of the towns and villages are located. We also predict that the infestation has potential to spread to yet unaffected towns and islands. It is estimated that the cost of treating all currently infested buildings in the archipelago is Euro 51 million, while reconstruction of the same buildings would rise the costs to Euro 175 million. We predict that the absence of a control strategy will cause a further expansion of the pest to more localities in the Azores. An estimate to future scenarios implies higher costs, with treatment and rebuilding values rising up to eight times the current values.

Seasonal allergic dermatitis in sheep in southern Brazil caused by Culicoides insignis (Diptera: Ceratopogonidae)

The incidence of seasonal dermatitis was studied in a Hampshire Down flock on a farm in southern Brazil. Epidemiological data, clinical signs and macroscopic pathology were obtained by visiting the farm. Histological lesions were studied in skin biopsies of affected sheep. Biting insects were collected from January to April 2005 in an attempt to identify the etiological agent of the disease. Disease prevalence was 40%; the age of the affected animals was variable. Disease occurred from December to March, some animals had lesions for the entire year. Clinical signs include pruritus on the ears, around the eyes and ventral abdomen. Initially erythema and small red papules were seen, followed by alopecia and crust formation. Histologically the lesions were characterized by perivascular eosinophilic dermatitis. Hyperkeratosis and acanthosis were observed in the chronic lesions. Both Anopheles albitarsis and Culicoides insignis were captured during the study. C. insignis bites caused pruritus in sheep. Both types of insects were caught when they approached the sheep baits approximately 30min after sunset. Results suggested that the disease occurred as a result of an immediate hypersensitivity reaction to C. insignis.

Effect of in vivo phenol or hydroquinone exposure on events related to neutrophil delivery during an inflammatory response

Phenol (PHE) and hydroquinone (HQ) are metabolites of benzene that affect leukocytes after solvent intoxication. Hence, we investigated the effects of PHE or HQ exposure on neutrophil mobilization during an inflammatory response. Male Wistar rats received intraperitoneal injections of PHE, HQ or vehicle only and assays were performed 24 h after the last dose. Quantifications of bone marrow or circulating leukocytes showed that only HQ exposure induced neutrophilia, probably due to the accelerated mobilization from the bone marrow compartment, since reduced numbers of segmented cells in the last phase of maturation were detected there. Intravital microscopy showed that circulating leukocytes of HQ-exposed rats increased their rolling behavior and adherence to the mesenteric postcapillary venule wall in vivo. The enhanced leukocyte-endothelium interaction was not dependent on microvascular reactivity or perivascular mast cell degranulation. Instead, it was the result of neutrophil activation, demonstrated by a decrease in L-selectin and an increase in beta2 integrin expression on neutrophil membranes. This pattern of neutrophil activation may have contributed to the higher number of neutrophils in the subcutaneous inflammatory response of HQ-exposed rats after oyster glycogen injection. Taken together, our results indicate that HQ exposure alters neutrophil mobilization, which results in an exacerbated response after an injury. Although PHE is endogenously metabolized to HQ, PHE exposure only induced an increment in rolling behavior, which was not sufficient to alter the inflammatory response.

Adenosine regulates the survival of avian retinal neurons and photoreceptors in culture

Adenosine modulates the survival of chick embryo retinal neurons in culture. When cultures were incubated for 3 days and refed with fresh medium, a large proportion of neurons died in the subsequent 3 days of culture. This cell death was prevented by preincubation of cultures for at least 24 h with adenosine plus the adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA), an adenosine uptake blocker nitrobenzylthioinosine (NBI), the adenosine A2A receptor agonist 2-[4-(2-carboxyethyl) phenethylamino]-5'-N-ethylcarboxamidoadenosine (CGS21680), or the permeant cyclic AMP analog 8-bromo cyclic AMP, but not the A1 receptor agonist cyclohexyladenosine (CHA). Adenosine deaminase induced cell death when added to culture medium, and this effect was prevented by EHNA. Cell death was not observed when the medium was replaced by a conditioned medium from sister cultures. The data strongly suggest that adenosine regulates the survival of developing retinal neurons by a long-term activation of A2A receptors and the increase of cyclic AMP levels.

Colloidal processing of hydroxyapatite

Reliable bioceramics are needed to implement the high requirements that living tissues demand. This work focuses on the processing steps necessary to manufacture advanced ceramics that can be used as implant devices. The influence of the heat treatment temperature on the characteristics of a precipitated hydroxyapatite (OHAp) powder was evaluated in order to obtain an appropriate specific surface area for colloidal processing. Ball milling of the calcined powders for 20 h was required to improve the rheological properties of the suspensions and the packing ability during consolidation. Different dispersing agents were tested and the first trial was made based on their effect on the zeta potential. The most promising ones were then selected and their efficiency was evaluated from rheological measurements and slip-casting performance of suspensions prepared at different solids loading. Targon 1128 was revealed to be the most efficient dispersant, enabling to prepare fluid suspensions containing 50 vol% solids and the highest green and sintered density values to be obtained.

Long-term activation of adenosine A(2a) receptors blocks glutamate excitotoxicity in cultures of avian retinal neurons

Previous work showed the presence of adenosine receptors as well as adenosine uptake and release mechanisms in developing chick retinal neurons in culture. In the present work we show that exogenous glutamate or kainate promotes extensive cell death in these cultures which is blocked when the cultures are previously incubated with adenosine. Addition of glutamate or kainate to purified cultures of retinal neurons and photoreceptors induced massive death of cultured cells which was inhibited in both cases by preincubation with MK801, an NMDA antagonist, or DNQX, an AMPA/kainate antagonist. Cell death was also greatly attenuated by preincubation with adenosine plus EHNA, an adenosine deaminase inhibitor, NBI, an adenosine uptake blocker, the permeable cAMP analogs 8-Br cAMP and Sp cAMP and the A(2a) agonists CGS 21680 and DPMA, but not with the A(1) receptor agonist CHA. Kinetic studies performed determining the intracellular LDH activity showed that maximal death was observed after 8 h and in concentrations of glutamate as low as 50 microM. We also observed a time-dependent protective effect of adenosine beginning after 1 h of preincubation and reaching a maximal effect after 24 h, indicating its association with changes in cellular metabolism induced by long-term exposure of cells to the nucleoside. The results show that adenosine inhibits glutamate toxicity in retinal neurons through a long-term activation of A(2a) receptors and elevation of intracellular cyclic AMP levels.

Fabrication of hydroxyapatite bodies by uniaxial pressing from a precipitated powder

Hydroxyapatite (OHAp) has been obtained by using a precipitation method. Thermal stability of the precipitated powder has been checked to define an appropriate working range to process ceramic bodies without the appearance of odd phases. Pellets of hydroxyapatite have been manufactured by means of uniaxial pressing and convenient thermal treatments have been investigated to achieve high density OHAp bodies. Finally, factors that could affect the ultimate mechanical properties of the sintered bodies prepared by uniaxial pressing have been discussed.

[Surgical treatment: in which patients and what type of intervention?]

In first place was described the treatment of myocardial revascularization, its indications, contra-indications and the advances in the last decade with best results. After was described the cardiomyoplasty and its results, the long-term mechanical circulatory support with various types of devices and finally the ventricular reduction (Batista op) with the short term results.

Influence of Temperature on Stability of Electrostatically Stabilized Alumina Suspensions

Pure electrostatically stabilized aqueous alumina suspensions were prepared at various solid loadings in order to study the influence of temperature on the surface charge properties and rheology. Surface charge density at various temperatures was measured through potentiometric titration, and the analysis of the potentiometric data was accomplished using the constant capacitance surface model. Calculations of the pair-wise interaction potential between charged colloidal spheres dispersed in water were then carried out using conventional DLVO theory and a software package Stabil45, taking into account the temperature dependence of surface charge density and dielectric constant. The results showed that increasing temperature leads to a gradual diminution of alumina surface ionization, dielectric constant, and a total energy barrier for coagulation. The enhancement of the coagulation rate with increasing temperature leads to a gradual increase of both relative apparent viscosity and thixotropy. Copyright 2000 Academic Press.

What are the limits for the Ross operation?

The Ross operation is physiologically the best approach for aortic valve replacement. At the Hospital de Santa Cruz 22 consecutive pulmonary autograft operations have been performed in patients with a mean age of 49 (range 17-65) years. Six patients had mitral valve disease, two had aortic aneurysms and one had a ventricular septal defect. Subcoronary implantation of the autograft was performed in 20 patients. A partial inclusion aortic root replacement technique was used in one and the aortic root was replaced in another. There were no hospital or late deaths. Two patients required autograft replacement at 3 and 9 months postoperatively because of regurgitation. One of these cases was caused by an abnormality of the pulmonary valve and since then echocardiographic assessments of this valve have been performed routinely and have detected significant pulmonary incompetence in four patients who otherwise would have been operated on using the Ross procedure.

Effects of continuous-wave CO2 laser on the ultrastructure of human dental enamel

Laser-induced changes in plano-parallel sections were examined by light microscopy (LM) and scanning electron microscopy (SEM), and correlated with ultrastructural changes as observed by transmission electron microscopy (TEM). LM and SEM revealed two different changes--extensive crazing, and crazing and cratering. Rough exposed enamel was commonly found, resulting from lifting off and removal of the top layer of crazed, or crazed and cratered, enamel. The type of induced change was mainly dependent on the energy density used (range approximately 0.8 to approximately 200 J cm-2) and on enamel prism orientation. Lased enamel was also softer than unlased enamel. TEM of both crazed enamel and rough exposed enamel revealed that most crystals generally resembled those of unlased enamel in size and shape, but that inter- and intra-crystalline voids were present in some areas. The crazed and cratered enamel had significant ultrastructural changes: new homogeneous and inhomogeneous crystals of apatite with a different shape and larger size than those of the original, and a loss of prismatic structure. The lack of uniformity of the laser effect on crazed and cratered enamel was shown by variation in crystal packing (from good to poor), variations in crystal size from area to area, and the presence of pockets of poorly packed homogeneous crystals alongside pockets of well-packed inhomogeneous crystals. The crazing, crazing and cratering, rough exposed enamel and the greater number of voids, as well as the relative softness of lased enamel do not indicate an overall ultrastructural improvement. However, the larger apatite crystal size and loss of prismatic structure in crazed and cratered areas may partly explain previous observations of reduced rates of subsurface demineralization in lased enamel.

[Comparative data of hospital morbidity in the municipality of Cubatão and in the State of São Paulo (Brazil)]

Realizou-se estudo com o objetivo de caracterizar a morbidade hospitalar do Município de Cubatão, SP (Brasil), comparando-a com a do Estado de São Paulo a fim de identificar as principais patologias e subsidiar a atuação dos serviços de saúde do Município. A caracterização da morbidade hospitalar baseou-se na análise dos dados coletados no período de julho/1983 a junho/1984. As principais causas de internação do Município de Cubatão nos três estabelecimentos hospitalares foram: Complicações da Gravidez, do Parto e do Puerpério (23,63%); Doenças do Aparelho Respiratório (22,8%); Doenças das Glândulas Endócrinas, da Nutrição e do Metabolismo e Transtornos Imunitários (10,47%); Doenças do Aparelho Circulatório (10,26%); Lesões e Envenenamentos (7,63%); Doenças do Aparelho Geniturinário (7,56%) e Doenças do Aparelho Digestivo (7,16%). Comparando-se o perfil da morbidade hospitalar de Cubatão com a do Estado de São Paulo observou-se que as Doenças Respiratórias, Doenças das Glândulas Endócrinas, da Nutrição, do Metabolismo e Transtornos Imunitários (compreendendo basicamente as desidratações) e as Lesões e Envenenamentos são muito mais freqüentes em Cubatão, o que pode estar refletindo as péssimas condições do meio ambiente, do saneamento básico, o baixo nível socioeconômico da população e o caráter altamente industrializado do Município. A baixa incidência das Doenças do Sistema Nervoso, dos Neoplasmas, Doenças do Sistema Osteomuscular e Anomalias Congênitas podem estar relacionadas com a precariedade dos serviços de saúde do Município que levam à procura de atendimento em outro local.

Is idiopathic hyperprolactinemia a transitional stage toward prolactinoma?

The basal prolactin (PRL) levels on five different days, the PRL responses to thyrotropin-releasing hormone and to domperidone, and the thyroid-stimulating hormone (TSH) responses to domperidone were studied in 75 regularly menstruating women and 44 patients with moderate hyperprolactinemia. It was found that, for the entire sample, the responses to each of the stimuli could be described by a continuous function of the basal PRL levels. The present work provides evidence for the following conclusions: 1) The PRL responses to thyrotropin-releasing hormone and to domperidone merely bring additional diagnostic information relative to basal PRL levels in the occasional patients with macroprolactinemia; 2) there is a continuous spectrum of lactotroph activities in women, ranging from normal secretors through an intermediate group of hypersecretors (with progressively increased serum PRL levels and decreased responsiveness to stimuli) to full-blown prolactinomas; and 3) idiopathic hyperprolactinemia is a heterogeneous entity that includes the above intermediate group of patients, women with macroprolactinemia, and patients with undiagnosed prolactinomas.

Distribution of elastic system fibers in the peripheral nerves of mammals

Various nerves of 6 representative species of mammals (including the human) were studied by the comparative association of the selective staining methods of light microscopy with the ultrastructural observation after tannic acid-glutaraldehyde fixation, which provided a reliable means of characterizing the different elastic system fibers. Although mature elastic fibers are not present in nerves, elastic-related fibers are frequently observed: oxytalan fibers are found mainly in the endoneurium, whereas elaunin fibers predominate in the epineurium. These fibers are longitudinally disposed, in a parallel orientation to the axons. The fact that these findings were consistently observed in the nerves of all species studied argues strongly in favor of the existence of a uniform structural pattern of distribution of elastic system fibers in nerves as a general phenomenon in mammals.

[Levels of anti-typhoid agglutinins in patients with hepatosplenic schistosomiasis]

Dois grupos, constituídos de 43 esquistossomóticos hepato-esplênicos e 83 indivíduos controle, foram analisados quanto à prevalência de aglutininas anti-tifoídicas. Os esquistossomóticos apresentaram freqüência maior de aglutininas anti-tifoídicas (H e/ou O e/ou Vi) e de aglutininas anti-O do que os indivíduos "normais". Apesar de que estes dados se devam, pelo menos parcialmente, à maior exposição natural dos esquistossomóticos aos antígenos estudados, sugere-se não estar ocorrendo deficiência na síntese de anticorpos, hipótese esta freqüentemente associada às baixas taxas de positividade de anticorpos anti-O encontrados nestes pacientes com bacteremia prolongada pela Salmonella.

Chromosome studies in Brazilian rams

A total of 127 rams from four breeds of sheep was karyotyped; 2.5 per cent had karyotype abnormalities. Two types of chromosomal variations were detected, both numerical mixopolids. From these animals, two presented a karyotype 54,XY/55,XY+mar and one 54,XY/55,XYY.

[Outbreak of toxoplasmosis in a Paulist seminary in Braganza (São Paulo state). Clinical, serological and epidemiological aspects]

Nove casos de toxoplasmose adquirida comprovada (forma linfoglandular), ocorridos em um Seminário de Bragança Paulista, motivaram uma investigação clínica e sorológica. De acôrdo com os dados assim obtidos, pelo menos 30 pessoas (em um total de 81) apresentavam toxoplasmose na ocasião. Ao todo, foram realizadas 314 reações de Sabin-Feldman e de imunofluorescência indireta. O inquérito sorológico pela prova do corante extendeu-se também a algumas espécies animais da localidade. Em vista das limitações relativas à investigação epidemiológica, foi possível apenas a colocação de várias hipóteses, nada se podendo concluir quanto aos aspectos epidemiológicos do surto. Registrando, pela primeira vez, na literatura médica esta ocorrência, os autores alertam para a possibilidade dêstes surtos em instituições fechadas ou zona rural. Insistem na necessidade de pesquisas mais profundas, em situações similares, para o reconhecimento das fontes de infecção e mecanismos de transmissão, a despeito das dificuldades decorrentes dos escassos conhecimentos sôbre a história natural da toxoplasmose e do ciclo biológico do parasita.