Roberto H Castelletto

Prevalence of celiac disease in argentina: screening of an adult population in the La Plata area

OBJECTIVES:Up to now, the epidemiological characteristic of celiac disease among adults in South America remains unknown. The present prospective screening was designed to determine the prevalence of celiac disease in adults from the general population in an urban area of Argentina.METHODS:Between January, 1998, and May, 2000, all couples attending a centralized laboratory for an obligatory prenuptial examination in the La Plata area were offered participation in a screening program for celiac disease. The study included 2000 subjects (996 women; median age 29 yr, range 16–79 yr). All individuals completed a clinical questionnaire at the time that serum samples were obtained. A three-step screening protocol was used, as follows: 1) all samples were tested for antigliadin antibodies (AGAs) (type IgA and IgG); 2) samples that were IgA AGA positive were tested for antiendomysial antibody (EmA type IgA); samples that were positive for AGA-G but negative for IgA AGAs were tested for total IgA serum levels and EmA type IgG; and 3) subjects who were EmA-positive were referred for intestinal biopsy.RESULTS:At the end of the screening we detected 10 subjects who were EmA-A positive and two others who were IgA-deficient (both were EmA-G positive). Up to now, 11 of the 12 subjects (including nine EmA-positive and two IgA-deficient subjects) had endoscopic intestinal biopsies showing the characteristic celiac histology. The remaining EmA-positive individual was considered to be affected by celiac disease. The overall prevalence assessed was 1:167 (6.0 × 1000 subjects; 95% CI = 3.1–10.5). Eight of the 12 (67%) subjects were female (1:124; 8.0 × 1000; 95% CI = 3.5–15.8) and four (33%) were male (1:251; 4.0 × 1000; 95% CI = 1.1–10.2). Although eight new patients were considered to be asymptomatic, three presented with a subclinical course and one was classically symptomatic. Only one patient had been previously diagnosed with celiac disease.CONCLUSIONS:Our screening protocol showed a very high prevalence of celiac disease for an urban area of Argentina that is ethnically similar to 90% of the general population of the country. The prevalence among women was double that for men, and the heterogeneous clinical picture of new patients showed predominance of asymptomatic cases.

Occult papillary thyroid carcinoma at autopsy in La Plata, Argentina

Although clinically evident thyroid carcinoma is not a frequent neoplasm (incidence 2.7 per 100,000 persons in La Plata, Argentina), occult carcinomas are present in a high proportion of the population, but there are marked differences along geographical lines. The purpose of the present study is to establish the prevalence of occult papillary thyroid carcinoma (OPC) in La Plata. Thyroid glands obtained from 100 consecutive adult necropsies were examined. The material was fixed in buffered formaldehyde at 4°C, serially sectioned at 2 mm intervals, and routinely processed. Eleven thyroid glands contained OPC, corresponding in three cases to multiple lesions. Eight carcinomas were found in 59 men (13.6%) and three in 41 women (7.3%). The ages ranged from 26 to 78 years. The neoplasms varied in size from microscopic foci to 9 mm in diameter. The prevalence rate of OPC in the present study is lower than that found in Finland, Japan, and the US, and higher than for the rest of the series recorded.

Value of a screening algorithm for celiac disease using tissue transglutaminase antibodies as first level in a population-based study.

OBJECTIVE:Serological screening for celiac disease (CD) can detect a large number of otherwise undiagnosed patients based on the sequential evaluation of serological tests and intestinal biopsy. The aim of this study was to compare the screening value for CD of two different protocols for the same community-based population.METHODS:We screened 1000 consecutive subjects (497 women, age range 16–71 yr) attending a centralized laboratory for obligatory prenuptial blood tests. Serum samples obtained from all subjects were processed using two different protocols: 1) a three-level classic screening consisting of the parallel use of IgG and IgA antigliadin antibodies as first level, followed by endomysial antibodies and total serum IgA for positive patients, and finally, intestinal biopsy of positive patients; and 2) a study screening protocol consisting of the parallel use of a commercial guinea pig antitissue transglutaminase antibody and total serum IgA as first line, endomysial antibodies (type IgA and/or IgG) for positive patients, and finally, intestinal biopsy.RESULTS:The classic screening protocol identified five subjects who were eligible for intestinal biopsy, which confirmed the presence of CD in all (prevalence 5.0 × 1000, 95% CI = 1.6–11.6). Using the study algorithm, we detected seven new patients including the five patients detected by the first protocol (prevalence 7.0 × 1000, 95% CI = 2.8–14.4). The two additional patients diagnosed using the proposed algorithm had positive IgG antigliadin antibodies and normal total serum IgA and were not detected by the classic protocol. Both patients were endomysial antibodies positive. The comparative analysis showed that the classic approach was more expensive (U.S.

Solid cell nests of the thyroid gland. Optic and immunohistochemical study at autopsies.

4687 per new patient detected) compared with the proposed study algorithm (U.S.

[Systematic study of gastrectomy specimens for cancer, in search of synchronous carcinomas].

3006).CONCLUSIONS:Our data showed that a new screening protocol using antitissue transglutaminase as first line followed by endomysial antibodies is a cost-effective screening and yielded more realistic figures of prevalence for CD in a community setting than the classic three-level sequential evaluation using antigliadin antibodies.

Solid cell nests of the thyroid

In order to establish the prevalence of solid cell nests (SCN) in adult thyroids, we studied 100 consecutive glands at necropsy. These were serially sectioned and stained with routine and immunoperoxidase techniques in order to detect calcitonin, carcinoembryonic antigen, thyroglobulin and keratin. SCN may be considered as normal thyroid gland components, and they share with C cells a common origin in the ultimobranchial body.