The importance of neurocysticercosis in stroke in rural areas of a developing Latin American country

Transcranial Doppler ultrasonography to evaluate cerebral hemodynamic changes in neurocysticercosis

BACKGROUND

 Arteritis is a complication of neurocysticercosis (NCC), which is not well known and could trigger strokes. The transcranial Doppler ultrasound (TCD) is a noninvasive method for detecting, staging, and monitoring cerebrovascular diseases. Nonetheless, the utility of TCD to evaluate cerebral hemodynamic changes, suggesting vasculitis associated with NCC remains uncertain.

OBJECTIVE

 To evaluate cerebral hemodynamic changes using TCD in patients with subarachnoid and parenchymal NCC.

METHODS

 There were 53 patients with NCC evaluated at a reference hospital for neurological diseases included (29 with subarachnoid and 24 with parenchymal). Participants underwent a clinical interview and serology for cysticercosis and underwent TCD performed within 2 weeks of enrollment. Mean flow velocity, peak systolic velocity, end diastolic velocity, and pulsatility index were recorded.

RESULTS

 Among the participants, there were 23 (43.4%) women, with a median age of 37 years (IQR: 29-48). Cerebral hemodynamic changes suggesting vasculitis were detected in 12 patients (22.64%); the most compromised vessel was the middle cerebral artery in 11 (91.67%) patients. There were more females in the group with sonographic signs of vasculitis (10/12, 83.33% vs. 13/41, 31.71%; p = 0.002), and this was more frequent in the subarachnoid NCC group (9/29, 31.03% vs. 3/24, 12.5%; p = 0.187), although this difference did not reach statistical significance.

CONCLUSION

 Cerebral hemodynamic changes suggestive of vasculitis are frequent in patients with NCC and can be evaluated using TCD.

Prevalence and incidence of stroke in Latin America and the Caribbean: a systematic review and meta-analysis

Stroke is a recurrent and well-known cardiovascular event and a leading cause of death worldwide. We identified reliable epidemiological evidence of stroke in Latin America and the Caribbean (LAC) and estimated the prevalence and incidence of stroke, overall and by sex, in that region. A systematic search in OVID (Medline, Embase and Global Health) and in the Latin America and Caribbean Health Sciences Literature (LILACS) until the end of 2020 was made for all cross-sectional or longitudinal studies estimating (or allowing the estimation of) the prevalence or incidence of stroke among individuals of the general population ≥ 18 years from LAC countries. No language restriction was applied. Studies were assessed for methodological quality and risk of bias. Pooled estimates were calculated using random effect meta-analysis as high heterogeneity was expected. A total of 31 papers for prevalence and 11 papers for incidence were included in the review for analysis. The overall pooled stroke prevalence was 32 (95% CI 26-38) per 1000 subjects and were similar among men (21; 95% CI 17-25) and women (20; 95% CI 16-23) per 1000 subjects. The overall pooled stroke incidence was 255 (95% CI 217-293) per 100 000 person-years, being higher in men (261; 95% CI 221-301) compared to women (217; 95% CI 184-250) per 100 000 person-years. Our results highlight the relevance of the prevalence and incidence of stroke in the LAC region. The estimates were similar in stroke prevalence by sex, but with higher incidence rates among males than females. Subgroup analyses highlight the need for standardized methodologies to obtain appropriate prevalence and incidence estimates at the population level in a region with a great burden of cardiovascular events.

Ischaemic stroke in young adults: a global perspective

Ischaemic stroke at young age is an increasing problem in both developing and developed countries due to rising incidence, high morbidity and mortality and long-term psychological, physical and social consequences. Compared with stroke in older adults, stroke in young adults is more heterogeneous due to the wide variety of possible underlying risk factors and aetiologies. In this review, we will provide an overview of the global variation in the epidemiology of stroke in young adults, with special attention to differences in geography, ethnicity/race and sex, as well as traditional and novel risk factors for early-onset ischaemic stroke, such as air pollution. Understanding global differences is an important prerequisite for better region-specific prevention and treatment of this devastating condition.

Ischemic stroke and infectious diseases in low-income and middle-income countries

PURPOSE OF REVIEW

To address the important relationships between stroke and infection, focusing on the most frequent infections found in low-income and middle-income countries.

RECENT FINDINGS

Stroke is one of the leading causes of mortality and disability worldwide, with a great proportion of the stroke burden occurring in low-income and middle-income countries. Infectious diseases are still a great health problem in developing countries and it is possible that the proportion of infection-related strokes is greater in these nations. Infectious diseases and stroke have a bidirectional relationship. Common infections may act as risk factors and can trigger stroke through different mechanisms in their acute phase. Several intracranial and systemic infections can cause stroke as a direct complication, such as Chagas disease, neurosyphilis, tuberculous meningitis, and neurocysticercosis. These conditions are of particular interest to low-income and middle-income countries, but also relevant to high-income nations because of increasing migration. Finally, infection is a frequent poststroke complication, with great impact in the patient outcome.

SUMMARY

Infectious diseases and stroke are common problems in low-income and middle-income countries. More studies are necessary to fully elucidate the real impact of infectious diseases on stroke burden, especially in countries where epidemiological data are still scarce.

Pathogenesis of Taenia solium taeniasis and cysticercosis

Taenia solium infections (taeniasis/cysticercosis) are a major scourge to most developing countries. Neurocysticercosis, the infection of the human nervous system by the cystic larvae of this parasite, has a protean array of clinical manifestations varying from entirely asymptomatic infections to aggressive, lethal courses. The diversity of clinical manifestations reflects a series of contributing factors which include the number, size and location of the invading parasites, and particularly the inflammatory response of the host. This manuscript reviews the different presentations of T. solium infections in the human host with a focus on the mechanisms or processes responsible for their clinical expression.

Calcified neurocysticercosis associates with hippocampal atrophy: a population-based study

Calcified neurocysticercosis has been associated with hippocampal atrophy in patients with refractory epilepsy, but the relevance of this association in the population at large is unknown. We assessed calcified cysticerci and its association with hippocampal atrophy in elderly persons living in Atahualpa, an Ecuadorian village endemic for neurocysticercosis. All Atahualpa residents ≥ 60 years of age were invited to undergo computed tomography/magnetic resonance imaging for neurocysticercosis detection. Twenty-eight (11%) out of 248 enrolled persons had calcified cysticerci (case-patients) and were matched 1:1 by age, sex, and years of education to individuals without neurocysticercosis on computed tomography/magnetic resonance imaging (controls). Four case-patients and none of the controls had epilepsy (P = 0.134). Cognitive performance was similar across both groups. The Scheltens' medial temporal atrophy scale was used for hippocampal rating in case-patients and matched controls without neurocysticercosis. Mean score in the Scheltens' scale was higher in case-patients than in controls (P < 0.001). Atrophic hippocampi were noticed in 19 case-patients and five controls (P = 0.003). Atrophy was bilateral in 11 case-patients and unilateral in eight. All case-patients with unilateral hippocampal atrophy had at least one ipsilateral calcification. This study shows an association between calcified cysticerci and hippocampal atrophy and raises the possibility of an inflammation-mediated hippocampal damage as the responsible mechanism for these findings.