Trends of accuracy of clinical diagnoses of the basic cause of death in a university hospital.

AIMS: To determine the agreement between clinical and necropsy diagnoses of the basic cause of death, and to compare the results with those obtained in a previous study carried out at the same university hospital. METHODS: In total, 4828 necropsies, performed between 1990 and 1995 in the University Hospital of the Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil, were reviewed. Examinations were concluded at the macroscopic part of the necropsy in nearly 35% of the cases. Statistical analysis was carried out using the kappa coefficient comparing the clinical diagnosis and the diagnosis obtained after necropsy. The jackknife method was used to identify comparable kappa values for the comparison of the two periods. RESULTS: Compared with the 1978-80 period, a significant increase in diagnostic agreement was seen for the group submitted to complete necropsy, whereas no similar increase was detected when only the macroscopic step was analysed. CONCLUSIONS: There was a discrete tendency to an improved correlation between clinical and postmortem data stated by full necropsy analysis. The findings show that microscopic analysis remains important to confirm the cause of death in many cases. Diagnostic discrepancies remained high, and therefore complete necropsy continues to be an essential instrument for the assessment of clinical diagnosis.

Immunolocalisation of myosin-V in the enteric nervous system of the rat.

We show here the localisation of myosin-V in whole mount preparations of the mucous-submucous and the muscular layers of rat small intestine by using an affinity purified antibody specific to the tail domain of myosin-V. Myosin-V immunostaining was intense in the submucous and myenteric nervous plexuses, allowing the visualisation of neuronal cell bodies and fibres. Western blots of total muscle layers homogenates detected with the same antibody revealed a single band of the expected size for myosin-V. Understanding the cellular localisation and function of this class of myosin is an important challenge and the accessibility and simplicity of the enteric nervous system as compared to the central nervous system, makes the digestive tract an attractive model for studying possible functional roles of myosin-V in neurotransmission and neuroplasticity.

The relationship between myenteric neuronal denervation, smooth muscle thickening and epithelial cell proliferation in the rat colon.

The effects of myenteric neuronal denervation on smooth muscle thickening and epithelial cell proliferation were studied in the descending colon of rats treated by serosal application of 2 mM benzalkonium chloride (BAC) for 30 min. Control animals were treated with saline (0.9% NaCl). The animals were divided into six groups of 13 animals each and killed 10, 45 and 120 days after BAC treatment. A significant reduction in neuron number was observed in the myenteric plexus of animals treated with BAC, as well as smooth muscle thickening and an increase in crypt cell population, crypt cell production per crypt and a decrease in cell cycle time. These findings permit us to conclude that a relationship may exist between the increase of epithelial cell proliferation, smooth muscle thickening and myenteric neuron denervation in the descending colon caused by BAC, the latter probably playing an important role in the integration of the other two.

[Jejunal myenteric denervation induced by benzalkonium chloride]. / Desnervação mioentérica jejunal induzida pelo cloreto de benzalcônio.

The effects of benzalkonium chloride (BAC) on the number of myenteric neurons, muscle thickness and external perimeter after acute (until 10 days after BAC application) and chronic (30 and 60 days after BAC application) denervation of the proximal jejunum were determined in rats. There was a significant reduction in the number of myenteric neurons of all segments treated with BAC. The extent of denervation varied along the time, and it was reduced in the denervated segments of the chronic group in comparison with the acute group. This may be due to the neuroplasticity phenomenon appearing during the chronic phase. Myenteric denervation increased the thickness of the propria muscle layer, especially in the longitudinal muscle layer, suggesting a higher sensitivity of this layer to myenteric denervation.

Myenteric neuron number after acute and chronic denervation of the proximal jejunum induced by benzalkonium chloride.

The effects of benzalkonium chloride (BAC) on the number of myenteric neurons after acute (until 10 days after BAC application) and chronic (30 and 60 days after BAC application) denervation of the proximal jejunum were determined in rats. There was a significant reduction in the number of myenteric neurons of all segments treated with BAC. The extent of denervation varied with time, and it was reduced in the denervated segments of the chronic group in comparison with the acute group. This may be due to the neuroplasticity phenomenon appearing during the chronic phase.

Accuracy of clinical diagnoses in a teaching hospital: a review of 997 autopsies.

OBJECTIVES: To analyse the concordance between clinical and autopsy diagnoses. DESIGN: Nine-hundred-and-ninety-seven autopsies were studied comparing the diagnoses of the autopsy requests with those of the death certificates and autopsy reports. The cases were grouped according to the 17 categories of diseases of the International Classification of Diseases (ICD) and the concordance was analysed with the kappa (kappa) coefficient of concordance. SETTING: The Hospital da Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRPUSP), Ribeirão Preto, SP, Brazil. SUBJECTS: The patients autopsied at HCFMRPUSP during the period between 1978 and 1980. MAIN OUTCOME MEASURES: kappa statistics offer an alternative approach to measuring the concordance between clinical and autopsy diagnoses. RESULTS: The kappa-value obtained was equal to 0.601 with a variance of 1.545 x 10(-4) when comparing the clinical diagnoses and the autopsy diagnoses, and equal to 0.661 with a variance of 1.531 x 10(-4) comparing the clinical diagnoses with those obtained after the gross examination. These values are significant at the level of 5%, i.e. there is an overall statistical concordance between clinical and autopsy diagnoses although the value is not absolute (kappa = 1.00). CONCLUSIONS: If autopsies are heeded without bias, they will continue to give important feedback concerning medical diagnosis.

A autopsia na historia / The autopsy in the history

A presente revisäo relata as possíveis interferências na aceitaçäo e/ou na rejeiçäo da realizaçäo de autópsias nos períodos da história, desde a pre-história até a idade contenporanea. Considerando os fatores que levaram ao seu sucesso até o início do século XX e também os fatores que tem levado a diminuiçäo das autópsias na última metade deste século. Dentro de cada período é feita pequena discussäo relacionando o momento historico com a autópsia e a possível importancia da mesma na História da Medicina

Effect of chemical ablation of myenteric neurones on intestinal cell proliferation.

The duodenum or descending colon of male Wistar rats (average weight 60 g) was treated by a serosal application of a 0.2% solution of benzalkonium chloride (BAC) for 30 min. Control animals were treated with 0.9% (physiological) saline. The rats were allocated to four groups: Group DC (N = 8) in which the duodenum was treated with physiological saline; Group DB (N = 8) in which the duodenum was treated with BAC; Group CC (N = 7) in which the descending colon was treated with physiological saline and Group CB (N = 7) in which the descending colon was treated with BAC. After treatment, the animals were followed up for 5 months. At the end of the experiment, the animals were injected intraperitoneally with vincristine sulphate before sacrifice. Three segments were removed from the duodenum and descending colon for neuronal counting, catecholamine and serotonin measurements and morphokinetic studies of the epithelium. The following results were obtained: (1) there was a significant reduction in neurone number in the myenteric plexus of segments treated with BAC; (2) in the denervated intestinal segments, catecholamine levels were unchanged whereas serotonin levels were increased; (3) epithelial hyperplasia was observed in the denervated duodenum and descending colon; and (4) crypt cell production rate in the duodenum was similar in groups DC and DB but was significantly increased in the descending colon in group CB as compared with controls (CC). The present findings indicate that selective myenteric neuronal denervation caused by benzalkonium chloride plays a causative role in the hyperplasia and crypt cell production rate of the intestinal epithelium (duodenum and descending colon). These changes are probably induced by functional imbalance by the surviving neuronal elements in the gut, implicating neurotransmitters such as acetylcholine, noradrenaline, serotonin, somatostatin and vasoactive intestinal peptide.