Absence of brain involvement and factors related to positive serology in a prospective series of 61 cases with pulmonary hydatid disease

A prospective series of 65 patients with surgically confirmed lung cystic hydatid disease was evaluated in terms of their radiologic characteristics, serologic response, and presence of cysts in other organs. Cysts were mostly single and located in lower lung lobes. Liver compromise was found in 34% of the patients. Despite a systematic search, no patient showed brain cysts in this series. Twelve patients had previous hydatid disease: six in the liver and eight in the lung (two had involvement of both organs in the past). Serology using bovine cyst fluid in an immunoblot assay was 85% sensitive. Serologic response was not associated with number or cyst or compromise of other organs but was clearly associated to the presence of at least one complicated cyst. Cyst status in terms of complications should be described to allow appropriate assessment of serologic evaluations.     

Short report: transient antibody response in Taenia solium infection in field conditions-a major contributor to high seroprevalence

The discordance between extremely high seroprevalence of Taenia solium antibodies in disease-endemic populations, relatively few symptomatic cases of neurocysticercosis, and high background levels of putatively inactive brain lesions (mainly calcifications) in seronegative controls have confused researchers, clinicians, and epidemiologists in the last decade. We reviewed longitudinal serologic data from general population serosurveys in 3 different disease-endemic areas of Peru and Colombia and found that approximately 40% of seropositive people were seronegative when resampled after 1 year (3 surveys) or after 3 years (1 survey). Transient antibodies may have significant implications for the epidemiology of and immunity to this disease.     

HLA class 1 associations in Henoch Schonlein purpura: increased and decreased frequencies

Henoch Schonlein purpura (HSP) is the most common vasculitis of childhood. Susceptibility to HSP and associated clinical heterogeneity in HSP may be conferred by a number of genetic loci, including the major histocompatibility complex. We aimed to investigate the implications of the human leukocyte antigen (HLA) class 1 alleles in susceptibility to HSP and determine the possible associations with renal, gastrointestinal (GI), and joint manifestations of the disease. 110 children with HSP (66 boys, 44 girls) and 250 unrelated healthy controls were enrolled in the study. The mean age was 8.65 ± 3.59 years. HSP was diagnosed on the basis of clinical and laboratory data according to the American College of Rheumatology classification. The diagnosis was supported with skin and/or kidney in most of the patients. Clinical and laboratory findings revealed: skin involvement in 110 (100%), joint manifestations in 82 (74.5%), GI symptoms in 58 (52.7%), and hematuria and/or proteinuria in 36 (32.7%) patients. HLA class 1 alleles were identified by DNA amplification, hybridized with specific primer sequences. Comparison of frequencies between patients and controls were made by using the Fisher’s exact test. Odds ratio (OR) was used as the measure of association. HLA A2, A11, and B35 antigens showed an increased risk for predisposition to HSP (OR = 1.714, 95%CI = 1.088–2.700, p = 0.020; OR = 2.185, 95%CI = 1.289–3.703, p = 0.003; and OR = 2.292, 95%CI = 1.451–3.619, p = 0.000, respectively), while HLA A1, B49, and B50 antigens revealed decreased risk for predisposition to HSP (OR = 4.739, 95%CI = 1.828–12.345, p = 0.001; OR = 3.268, 95%CI = 0.955–11.236, p = 0.047; and OR = 7.462, 95%CI = 0.975–55.555, p = 0.024, respectively). Considering the renal involvement and severity of proteinuria, there was no association with HLA class 1 alleles. Our results suggest that the increased frequency of HLA A2, A11, and B35 alleles in unselected pediatric HSP patient population and miscarrying of HLA A1, B49, and B50 could be considered as a risk factor for susceptibility to HSP.     

Failure of one-day praziquantel treatment in patients with multiple neurocysticercosis lesions

A recently described one-day regimen of praziquantel (PZQ) therapy for neurocysticercosis (NCC), three doses of 25 mg/k given at 2 h intervals, was applied in eight patients with viable NCC cysts without any evidence of inflammation. Resolution of lesions in computed tomography (CT) was observed in all five patients with a single cyst, whereas all cysts survived in three patients with multiple brain parasites. One-day praziquantel is a good regimen for patients with a single viable brain cysticercus but is poorly effective for multiple cysts.     

Strategies for the elimination of taeniasis/cysticercosis

Advances in the field of neurocysticercosis continue to shape our understanding of the disease and our efforts to control it. Several attempts have been made to eradicate the disease with active interventions such as changing domestic pig-raising practices, mass chemotherapy of porcine cysticercosis and taeniasis, selective detection and treatment of taeniasis, and community health education. Moreover, ongoing progress in the diagnosis of taeniasis and the development of a porcine vaccine against cysticercosis in Australia, Mexico and Peru has yielded at least one effective vaccine that is currently available. Thus far, however, attempted interventions have only been successful in temporarily disrupting transmission of the disease. Controlled data on the efficacy and acceptability of the different interventions is urgently needed to provide a base-line schematic for intervention which could later be tailored to each particular endemic scenario.     

To know what it is for, but not how it is: semantic dissociations in a case of visual agnosia

We report the case of a woman who displayed impaired object recognition following a severe head injury. Her elementary visual functions were substantially preserved, allowing her a coherent percept. On the other hand, she was impaired in accessing stored knowledge from both visual and verbal input. In particular, she showed a dramatic dissociation between fully preserved access to functional knowledge, and severely impaired access to perceptual knowledge so that she could describe what objects are for, but not how they are. Our findings from this case suggest that different categories of object knowledge are represented independently in separate units within the semantic system.     

Sluggish engagement and disengagement of non-spatial attention in dyslexic children

Although the dominant view posits that developmental dyslexia arises from a deficit in phonological processing and memory, efficient phonological decoding requires precise visual selection of graphemes. Therefore, visual engagement and disengagement of non-spatial attention were studied in 13 dyslexic children and 13 chronological age and intelligence quotient (IQ) matched normally reading children by measuring "attentional masking" (AM) and "attentional blink" (AB) effects. AM refers to an impaired identification of the first (T1) of two rapidly sequential targets (i.e., attentional engagement). In contrast, AB refers to an impaired identification of the second target in the sequence (T2; i.e., attentional disengagement). The results revealed a specific temporal deficit of AM as well as of AB in dyslexic children. Our results showed that the abnormality in AM and AB is rather widespread, since 77% and 54% of dyslexic children deviated at least 1 standard deviation (SD) from the mean of the controls, respectively, for the two deficits. We further showed that individual differences in non-spatial attention were specifically related to nonword reading ability. These results suggest that non-spatial attention deficits (possibly related to a parietal cortex dysfunction) may selectively impair the reading development via sub-lexical mechanisms.     

Economic burden of neurocysticercosis: results from Peru

Neurocysticercosis (NCC) is a major cause of neurological morbidity in the developing world. This study aimed to assess the treatment costs and productivity losses associated with NCC in Peru. NCC patients were identified through retrospective chart analysis. Patients meeting inclusion criteria were interviewed in order to obtain data on symptom history, treatment costs, productivity losses and health service utilisation patterns. These data were modelled to determine average treatment costs and productivity losses over 2 years. Our findings show that treatment costs and productivity losses consume 54% of an annual minimum wage salary during the first year of treatment and 16% during the second year. Diagnosis (36%) and drug therapy (27%) represent the most expensive healthcare-related costs. These costs are prohibitive for some-8% of our study sample had no diagnostic tests during their first 6 months of disease, and two-thirds of those who delayed treatment reportedly did so due to their inability to pay. Two-thirds of wage-earners lost their jobs owing to NCC and only 61% were able to re-engage in wage-earning activities. This study highlights the need to expand financial coverage to ensure the poor have access to health services and do not become further impoverished.