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J C Prolla

Publications and source records attributed to J C Prolla.

At least 19 recordsLinked to original sources
PubMed2001

Karyometry in Barrett's esophagus.

OBJECTIVE: To derive a progression curve for lesions in Barrett's esophagus based on karyometric features. STUDY DESIGN: High-resolution imagery of 900 nuclei from normal gastric tissue, Barrett's metaplasia, Barrett's high grade dysplasia and adenocarcinoma of the esophagus was recorded. Karyometric features were computed, and nuclear signatures and lesion signatures for these lesions were derived. A progression curve was defined. RESULTS: Esophageal lesions were distinctly different from the normal gastric fundus tissue, with nuclei from Barrett's metaplasia deviating from normal almost as much as nuclei from high grade dysplasia and adenocarcinoma. There was considerable case-to-case variability and overlap between lesions histologically assigned to different diagnostic categories. CONCLUSION: The karyometric data suggest that Barrett's metaplasia is a more developed lesion than previously assumed.

Adenocarcinoma↗
PubMed1999

Esophageal dysplasias are detected by endoscopy with Lugol in patients at risk for squamous cell carcinoma in southern Brazil.

Diagnosis of squamous cell carcinoma of the esophagus is usually late. Staining of the mucosa with Lugol's solution during endoscopy has been suggested to identify early cancer/dysplasia and may improve prognosis. Lugol was tested during endoscopy in 96 asymptomatic subjects at risk for this tumor, who were found to have atypias after exfoliative cytology in southern Brazil. Biopsies were obtained in Lugol's 'stained' and 'unstained' areas in the esophageal mucosa and the histologic results were compared. 'Unstained' areas were present in 64 (66.7%) instances: 44 'unstained' areas over mucosa with normal appearance revealed seven dysplasias (four high and three low grade), whereas 20 'unstained' areas with visible lesions contained only one dysplasia (low grade). 'Stained' areas in 96 (100%) subjects showed two additional dysplasias (one high and one low grade). In this study, Lugol 'unstained' areas were of great value for detection of dysplasias (sensitivity = 80%; specificity = 63%; p = 0.01, Fisher's exact test; CI = 95%; odds ratio = 6.7).

Aged↗
PubMed1997

Comparison of conventional microscopy and digitized imaging for diagnosis in serous effusions.

OBJECTIVE: To compare diagnoses made from conventional microscopy and digitized imaging in preparation for teleconsultation cytopathology services that are affordable and efficient. STUDY DESIGN: One hundred six consecutive serous effusions received in the cytopathology laboratory of a general hospital in Porto Alegre, RS, Brazil, were studied. The diagnoses by the senior cytopathologist at the conventional microscope were considered the standard and identified 61 cases negative and 45 positive for malignant cells (40 epithelial and 5 nonepithelial). The same pathologist digitized 461 selected fields for analysis by a second experienced cytopathologist (observer A) and a senior cytotechnologist (observer B) without knowledge of the standard diagnoses. Ten cases were studied in daily sessions of one hour each. The diagnoses were negative for malignant cells, positive for malignant cells (epithelial) and positive for malignant cells (nonepithelial). RESULTS: The following kappa values were found: 0.91 (observer A and observer B versus standard) and 0.86 (observer A versus observer B). CONCLUSION: Remote digitized imaging diagnosis in serous effusions is possible and has a high degree of concordance with diagnosis by conventional microscopy. Similar studies involving a larger group of cytopathologists and cytotechnologists should be done to identify interobserver variability.

Ascitic Fluid↗
PubMed1996

Correlation of endoscopic cytology and histology in oesophageal cancer: results in Porto Alegre, RS--Brazil.

A retrospective study of oesophageal cytopathology at the Hospital de Clinicas de Porto Alegre (HCPA), RS, Brazil, from 1989 to 1992 was made assess the sensitivity, specificity, predictive values and accuracy of endoscopic cytology and biopsy; and study the correlation between cytopathological and histopathological diagnosis. Specimens from 94 patients were available for review. The final diagnosis was based on surgical pathology and follow up. The 81 patient with cancer of the oesophagus had the following sex distribution: 64 males and 17 females(a 3.7-1 ratio). No tumour was found in 13 patients. The following conclusions were made: (i) there is excellent correlation between cytology and histology in oesophageal lesions sampled by endoscopy; (ii) a correct positive cytologic report was obtained in 77 (95%) of the 81 proven oesophageal cancers; a false-negative or unsatisfactory result was given in four patients. A false-positive diagnosis of cancer was not made. There were 13 true-negative reports. These findings result in a sensitivity of 83% with 95% CI of 74.82-91.18%; a specificity of 100% (CI of 98.5-100%) a positive predictive value of 100% (CI of 99.25-100%); a negative predictive value of 48% (CI of 29.16-64.84%); (iv) of 81 patients with proven cancer, in 79 (98%) at least one of the methods was positive. In only two patients with cancer were both methods negative. These finding result in a combined sensitivity of 98% (CI of 94.92-100%); a specificity of 100% (CI of 98.5-100%); a positive predictive value of 100% (CI of 99.31-100%); and a negative predictive value of 87% CI of 70-100%). Our series confirms the value of the combined use of cytology and biopsy for the investigation of oesophageal lesions.

Adenocarcinoma↗
PubMed1994

Pleural fluid adenosine deaminase and lymphocyte proportion: clinical usefulness in the diagnosis of tuberculosis.

Adenosine deaminase (ADA) and lymphocyte proportion are known to be independently elevated in tuberculous effusions, but are non-specific, and false positive results are frequent. To overcome this problem the combined use of both parameters was prospectively studied in 276 patients with pleural effusion seen at Porto Alegre, Brazil. Using a cut-off level of 40 U/l at 37 degrees C (method of Giusti19) for ADA activity and lymphocyte proportion of more than 50%, the correct diagnosis of tuberculosis (sensitivity) was made in 90.7% (CI 87.3-94.1%) of 54 patients. A specificity of 97.7% (CI 95.9-99.5%) was recorded. Five false positive diagnoses of tuberculous effusion were made. Five false negative diagnoses were made: three cases with haematogenous tuberculous dissemination with low ADA levels, and two other patients with low lymphocyte proportion. The combined use of ADA activity determination and lymphocyte proportion is a highly efficient diagnostic strategy of low cost, that merits wider use.

Adenosine Deaminase↗
PubMed1993

The diagnosis of Pneumocystis carinii pneumonia by cytologic evaluation of Papanicolaou and Leishman-stained bronchoalveolar specimens in patients with the acquired immunodeficiency syndrome.

The presence of foamy alveolar casts or flocculent material in Papanicolaou and Leishman-stained smears of bronchoalveolar lavage (BAL) fluid is said to be indicative of infection with Pneumocystis carinii. We have investigated the sensitivity and specificity of this method of diagnosing pneumocystis pneumonia in patients with the acquired immunodeficiency syndrome (AIDS). Patients (n = 114) with diffuse lung infiltrates were submitted to fibreoptic bronchoscopy and BAL. Seventy of them were patients with AIDS. The other 44 individuals were not infected by the human immunodeficiency virus (HIV). Pneumocystis carinii organisms were identified on Grocott's methenamine silver (GMS)-stained BAL smears in 30 patients with AIDS. Flocculent material was present in the Papanicolaou and Leishman-stained smears from all of these cases. Conversely, P. carinii were not seen on GMS-stained smears in the remaining 84 individuals with or without AIDS. No flocculent material was observed in Papanicolaou or Leishman-stained smears in these 84 patients. We concluded that the presence of flocculent material in Papanicolaou or Leishman-stained smears of BAL fluid is indicative of P. carinii pneumonia in patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Upper gastrointestinal fiberoptic endoscopy in pediatric patients.

Upper gastrointestinal fiberendoscopy in pediatric patients is done safely and under local anesthesia in most instances. This study of 47 children confirmed the value of fiberendoscopy in establishing the etiology of upper gastrointestinal hemorrhage and the presence of esophageal varices. It also contributed significantly to the management of patients with disphagia, pyrosis, epigastric pain, and ingestion of foreign bodies. No significant morbidity was caused.

Abdomen↗
PubMed1979

Clinical evaluation of eosinophils in the sputum.

The sputum differential eosinophil/neutrophil count was done in 384 patients using Leishman staining. The patients were distributed in four groups: bronchial asthma (197 patients); chronic bronchitis with wheezing (45 patients); chronic bronchitis and/or emphysema without wheezing (73 patients); other pulmonary diseases (64 patients). Eosinophils were present in patients from all groups but more frequently (P less than 0.001) in asthma: 142 (72%) of 197 patients. In bronchial asthma and chronic bronchitis with wheezing the percentages of eosinophils were more frequently (P less than 0.001) above 80%: 57% and 58% of the patients respectively. The other two groups had more cases with 19% or less eosinophils. There is no percentage level specific for asthma but levels above 80% of eosinophils are strongly suggestive of asthma or of chronic bronchitis with wheezing.

Asthma↗