Factors related to inter-observer reproducibility of conventional Pap smear cytology: a multilevel analysis of smear and laboratory characteristics.

OBJECTIVE: To identify factors that influence the inter-observer reproducibility of the routine, conventional Pap smear cytology (Pap smear test) in a network of certificated laboratories in a middle-income Latin American country. METHODS: Twenty-six laboratories provided each an average of 26 negative for malignancy (NILM) and high-grade squamous intraepithelial lesion (HSIL) Pap smears. An external panel reviewed the slides. The kappa index and multilevel logistic regression were used to estimate the reproducibility and odds ratios (OR) of a false result with 95% confidence intervals (95% CI), respectively. Results are presented for laboratories that collect (collector laboratories) and do not collect (non-collector laboratories) samples. RESULTS: The agreements ranged widely (median kappa 0.51, range 0.16-0.70). The overall false-positive (FP) and false-negative (FN) rates were 31% (95% CI 27-35) and 11% (95% CI 7-17). Among collector laboratories (N = 14), a bigger sample collection volume decreased the probability of a FP (OR-adjusted 0.05, 95% CI 0.02-0.1) whereas the number of quality defects (OR-adjusted 1.67, 95% CI 1.25-2.24), high workload (OR-adjusted 5.52, 95% CI 3.85-7.92) and collection by cytotechnologists (OR-adjusted 1.28, 95% CI 1.15-1.42) or health professionals (OR-adjusted 2.26, 95% CI 2.04-2.49) instead of nursing assistants increased it. Among non-collector laboratories (N = 9), the FP rate increased with the number of quality defects (OR-adjusted 1.86, 95% CI 1.06-3.26) but decreased if the samples were collected by health professionals instead of nursing assistants (OR-adjusted 0.37, 95%CI 0.17-0.80). No significant associations were observed for FN. CONCLUSIONS: Staff in charge of cervical sampling significantly determined the reproducibility of the Pap smear test, but this depended on whether the laboratory collects samples or read samples collected elsewhere.

[Colon biopsy--histological characteristics in different types of chronic colitis]. / Biopsia de colon: características histológicas en diferentes tipos de colitis crónica.

In the last few years a variety of new forms of chronic colitis have been described with defined histological characteristics. It is important both for the gastroenterologists and pathologists to be acquainted with this new clinic pathological entities. The present article is a review of the anatomo-pathological characteristics of the different types of colitis.

Biopsia de Colon: Características Histológicas en diferentes tipos de Colitis Crónica / Biopsy of Colon: histological features in different types of Chronicle Colitis

En los últimos años han aparecido diferentes tipos de colitis con características histológicas definidas. Es importante que tanto el gastroenterólogo como el patólogo estar actualizados respecto a estas nuevas entidades clínico-patológicas. El presente trabajo es un artículo de revisión sobre las características histopatológicas de los diferentes tipos de colitis.

In the last few years a variety of new forms of chronic colitis have been described withdefined histological characteristics. It is important both for the gastroenterologists andpathologists to be acquainted with this new clinic pathological entities.The present article is a review of the anatomo-pathological characteristics of the differenttypes of colitis.

[Life-saving total gastrectomy in abdominal sepsis after bariatric surgery of gastric sleeve]. / Degastrectomía total salvadora de vida en sepsis abdominal post cirugía bariatrica de manga gástrica.

Three obese patients underwent sleeve gastrectomy. They developed gastric dehiscence with generalized peritonitis, sepsis and shock, being operated as total gastrectomy of the remanent stomach with Roux in Y esophago-jejunostomy reconstruction as a last chance of life saving procedure.

Comparación de la prevalencia de la infección del estómago por el Helicobacter pylori en el Perú en población japonesa y peruana / Comparison of the prevalence of Helicobacter pylori stomach infection in Peruvian and Japanese population

Se ha planteado la posibilidad de una predisposición racial para adquirir la infección del estómago por el Helicobacter pylori. Sin embargo, no se ha tenido en cuenta el nivel socioeconómico de los pacientes. Objetivo: Comparar la prevalencia de la infección por Helicobacter pylori en la población japonesa residente en el Perú y en peruanos nativos, con similares condiciones socioeconómicas. Material y métodos: Estudio prospectivo realizado en el Policlínico Peruano-Japonés (Lima-Perú), donde incluimos a dos grupos de pacientes: japoneses y peruanos nativos con síntomas crónicos del tracto gastrointestinal superior, ambos de nivel socioeconómico medio y alto. Se excluyeron pacientes con úlcera péptica. Para diagnosticar la infección se utilizó la prueba de la ureasa, la Reacción en Cadena de la Polimerasa (PCR) y serología con ELISA IgG. Resultados: Evaluamos 168 pacientes de raza japonesa (edad promedio 54.6±12.62 años, 75% mujeres), y los comparamos con 161 peruanos (edad 42.12±14.48 años, 61.5% mujeres). Utilizando la prueba de la ureasa, la prevalencia de infección por el Helicobacter pylori en peruanos fue de 47.8% y en japoneses de 47.0% (p=0.88). Utilizando PCR, en peruanos fue de 49.7% y en japoneses 43.5% (p=0.28). Conclusiones: En el Perú, las personas de raza y ascendencia japonesa pura comparados con población peruana del mismo estrato social y similar grupo etáreo, tienen similar prevalencia de la infección por el Helicobacter pylori, con lo que podemos postular que en el Perú y en estos grupos étnicos no existe predisposición racial para adquirir la infección.

Objective: To compare the prevalence of Helicobacter pylori infection in native Peruvians and Japaneses residing in Peru. METHODS: Prospective study carried out at [quot ]Policlinico Peruano-Japonés[quot ] (Lima-Perú). We included Peruvians and Japaneses residing in Peru with chronic symptoms of the upper gastrointestinal tract. Both groups were from medium to high socioeconomic status. We excluded patients with peptic ulcer. PCR, rapid ureasa test and IgG ELISA were used to diagnose the infection. RESULTS: We evaluated 168 Japaneses (mean age 54.6 +/- 12.62 years, 75% female), and 161 Peruvians (mean age of 42.12 +/- 14.48 years, 61.5% female). Using the rapid ureasa test, the prevalence of Helicobacter pylori infection in Peruvians was 47.8%, and in Japaneses 47.0% (p=0.88). Using PCR, in Peruvians was 49.7% and in Japaneses 43.5% (p=0.28). CONCLUSION: Peruvians and Japaneses residing in Peru have a similar prevalence of Helicobacter pylori infection, after controlling factors such as socioeconomic status and age, suggesting that in Peru and in these ethnic groups, there is no racial predisposition to acquire the infection.

Normal and abnormal mitoses in the atypical endometrial change associated with chorionic tissue effect [corrected].

The presence of mitotic figures was investigated in 215 cases of florid atypical endometrial change associated with chorionic tissue effect. Mitoses were found in 13.4% of the cases. Mitoses were occasionally observed in 10.2% of cases, and they were multiple in single microscopic fields in 2.7%. Abnormal mitoses were noted in 3.2% of the cases. The occurrence of normal and abnormal mitoses was mainly related to the early secretory type of abnormality. These observations have biologic implications, but of more practical interest, they indicate that the presence of mitoses per se are an insufficient criteria for the diagnosis of clear-cell carcinoma, particularly in women during their reproductive period.

Hemangiopericytoma of the breast.

Hemangiopericytoma, an uncommon neoplasm derived from pericytes, occurs in many locations throughout the body. The clinical course of this tumor is variable with the most malignant lesions capable of producing metastases. This report describes 5 patients who had hemangiopericytoma of the breast. All were women between 47 and 57 yr old. The tumors varied from 3.2 to 19 cm (average, 9 cm). Three were treated by mastectomy and two by local excision. All remained disease free for a median duration of 22 mo and for an average of 46 mo (3 to 144 mo). We have found eight additional already published examples of mammary hemangiopericytoma in adult women ranging in age from 33 to 67 yr (average, 51 yr). The tumors averaged 6 cm (1 to 29 cm) in diameter. Three were treated by mastectomy and 5 by excision. All 8 patients remained disease free at last follow-up, averaging 84 mo (16 to 276 mo). Thus, it appears that hemangiopericytoma arising in the breast is a clinically low-grade form of sarcoma regardless of tumor size. Whenever possible, initial treatment should be complete local excision with breast preservation. Total mastectomy may be necessary for exceptionally large lesions.

Verruga peruana mimicking malignant neoplasms.

We have shown that in some cases fully developed florid verruga peruana nodules, as well as late-resolving, deeply situated lesions, can histologically suggest a variety of tumors to experienced pathologists. The compact proliferation of endothelial cells characteristic of florid verruga lesions can give rise to two pseudoneoplastic histologic patterns. One consists of sheets or islands of cells arranged in an epithelioid or pseudoepithelioid pattern (cases 1 and 2) in which the following histologic diagnoses were considered: squamous carcinoma, sweat gland carcinoma, epithelioid hemangioendothelioma, epithelioid sarcoma, melanoma and metastatic carcinoma. The other pattern of the florid lesion is characterized by a predominantly spindle cell arrangement (case 3) and in it the following diagnoses were made: Kaposi's sarcoma, fibrosarcoma, melanoma and leiomyosarcoma. The dense lymphoplasmacytic and histiocytic infiltrates of the late-resolving, deeply situated nodules (case 4) suggested the following histologic conditions: malignant lymphoma, nodular Hodgkin's disease, reticuloendotheliosis, and reticulosarcomatosis. Some histologic features thought to be of value to help in the differential diagnoses are discussed. It is emphasized that only the finding of Rocha-Lima's inclusions on light-microscopic studies and/or the demonstration of bartonella organisms in the lesions by electron-microscopic studies can objectively establish a diagnosis in a given lesion. However, knowledge of the epidemiologic data and particularly the presence of other lesions in the patient make it relatively easy to rule out neoplasia.

Histology, immunohistochemistry, and ultrastructure of the verruga in Carrion's disease.

Twenty-six verruga peruana nodules were studied. The presence of Factor VIII-related antigen and Ulex europaeus lectin binding, and the ultrastructural finding of rudimentary cell junctions and pinocytotic vesicles establish the endothelial character of the proliferating cells in the verruga nodules. Whereas superficial lesions could show an angiomatoid pattern, deep-situated nodules tended to present a compact type of growth. Electron-microscopic studies have shown that Bartonella bacilliformis was found abundantly in the extracellular spaces in the florid lesions and that no organisms were present in the late, resolving subcutaneous nodules. Although no true intracellular "viable" microorganisms were noted, pseudopods of cytoplasm entrapping one or two bacteria and surrounding matrix substance were seen often. The characteristics of cytoplasmic inclusions previously described in verruga cells as "chlamydozoa" were detailed. The ultrastructure of the inclusions corresponded to endothelial phagocytic cells in which complex invaginations of the cell surface had produced a labyrinth of interconnected channels and vacuoles containing degraded bacteria, extracellular matrix components, or both. We conclude that in light microscopy the finding of Rocha-Lima's inclusions is the only definite morphologic evidence of the presence of bartonella in verruga lesions.

Chronic hypoxia and chemodectomas in bovines at high altitudes.

A severe degree of hyperplasia of the chief cells occurs in bovine carotid bodies at high altitudes, compared to sea level. As a result, the carotid body from an animal at high altitudes is significantly heavier and larger than the carotid body from an animal at sea level (P less than .001). In eight of 20 (40%) animals at high altitudes, the hyperplastic reaction had progressed to form chemodectomas. The findings suggest that neoplasia can result from chronic stimulation by a biologically essential environmental factor (atmospheric PO2) that acts pharmacologically on the target tissues (chief cells of the carotid body).

Chief cell hyperplasia in the human carotid body at high altitudes; physiologic and pathologic significance.

The area occupied by parenchymal cells, in sections comprising the entire half of the surface of the carotid body, is significantly greater in people born and living at 14,350 feet than in those at sea level. The enlargement and increase in weight of the carotid bodies observed at high altitudes can thus be attributed to hyperplasia of parenchymal tissue. The proliferated cells have the morphology of type I chief cells and display marked vacuolation and depletion of yellow-green, naturally fluorescing, bioamine containing granules. Although unimportant variations in size and weight in relation to age occurred at sea level, it was found that the magnitude of the carotid body enlargement increased with age at high altitudes. The augmented carotid body size and weight in relation to age at high altitudes are associated with progressive chemoreceptor insensitivity. The physiologic and pathologic significance of these findings is discussed.

Immunosuppression and toxoplasmic encephalitis: clinical and experimental aspects.

Encephalitis developing after prolonged antineoplastic therapy in two patients with Hodgkin's disease and in one with multiple myeloma was found at autopsy to be caused by toxoplasmosis. To better understand the pathogenesis of the brain lesions, ranging from microscopic foci to some having a diameter of 6 cm. and characterized by proliferation of the organisms at the margins of expanding necrosis, an animal model was studied. Similar lesions were produced in hamsters by inducing relapse of chronic latent toxoplasmosis through administration of cortisone, cyclophosphamide, or whole body irradiation, but toxic doses of nitrogen mustard and urethane did not precipitate relapse. Notably, relapsing toxoplasmosis generally involves the brain exclusively, suggesting a special susceptibility related to immune mechanisms. The roles of cells and of antibodies in immune surveillance against this chronic infection in otherwise normal hosts are considered. In man the suppression of cellular immunities by certain antineoplastic agents would seem to be decisive in causing relapse of toxoplasmosis, rather than the replacement of immunologically active cells by neoplasm. Because the infection can be controlled with sulfadiazine and pyrimethamine, a high index of suspicion is essential to detect incipient cerebral toxoplasmosis. serial serologic testing is helpful by demonstrating titer elevations; however, poor antibody production or transferred antibody may be misleading clinically when single tests are evaluated. Similarly, a poor inflammatory cell response can make it difficult for the histopathologist to detect small lesions in these patients.