Analysis of biochemical constituents of the vitreous humor can be useful in determining the postmortem interval as there is proportionate postmortem rise of potassium and fall in sodium concentration. We studied 120 autopsy cases to determine the utility of potassium, sodium, calcium, and chloride levels, and sodium/potassium ratio in estimating the postmortem interval. There was a linear relationship between vitreous potassium concentration and postmortem interval, whereas an inverse relationship between vitreous sodium/potassium ratio and postmortem interval was noted. Other factors like age, sex, cause of death, season of death, and refrigeration of sample did not influence the vitreous humor potassium values. Using the statistical tools, a new formula was derived to determine the postmortem interval based on the potassium concentration and a review of previous literature is presented. Hence, the findings of this study supported a central role of vitreous humor biochemistry in many postmortem forensic and pathological evaluations.

Over the last few years there has been a rise in the incidence of fatal malaria in urban areas of India, and this worrying trend is a major cause of concern for the national health authorities. The spectrum of histopathological changes that occur in the livers of Indian subjects with fatal malaria has recently been investigated, in a retrospective autopsy-based study. This investigation involved the 151 fatal cases of malaria seen at a tertiary-care hospital in Mumbai between January 2001 and December 2007. The diagnosis of malaria was made on the basis of the examination of a smear of peripheral blood (81 cases) or a histopathological examination (70 cases). For each subject of the present study, at least two blocks were prepared, using routine histological methods, from a liver sample collected at autopsy. The sections produced from these blocks were stained with various compounds, including Prussian Blue (which was used to distinguish malarial pigment from non-malarial). The pattern of liver necrosis seen in the malaria cases was compared with that seen in 11 cases of acute viral hepatitis, and with the liver histology seen in 50 control subjects, who had died of causes other than malaria or liver disease. The most common clinical presentation of the subjects who died of malaria was fever (85%), followed by jaundice (68%). The presence of jaundice often led to an initial misdiagnosis of acute viral hepatitis. In the livers of the fatal malaria cases, Kupffer-cell hyperplasia and the retention of haemozoin pigment were the two most common histological features. Necrosis was seen in 63 (41%) of these cases, with predominant centrilobular haemorrhagic necrosis in 16 (10%). The inflammation in the sections of liver from the malaria cases with hepatic necrosis was sparse compared with that in the corresponding sections from patients with acute viral hepatitis, although mixed portal inflammation was frequently noted in the malaria cases. None of the liver sections from the 50 control subjects showed evidence of pigment, necrosis or any other pathology. In conclusion, jaundice was one of the commonest clinical presentations of the fatal cases of malaria and could mimic viral hepatitis on clinical examination. The characteristic histopathological features of the livers of those with fatal malaria were Kupffer-cell hyperplasia, malarial pigment within the Kupffer cells, and liver-cell necrosis, with portal inflammation, steatosis and cholestasis also observed.

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Soft tissue tumors are diagnostically challenging, and it is recommended that these are reported or reviewed by specialist soft tissue pathologists. We present our experience with second-opinion (consultation) cases in a specialist tertiary sarcoma center. The aim of this study was to determine areas of diagnostic difficulty in soft tissue pathology. We assessed 581 second-opinion cases which were reviewed by two experienced pathologists in a period of one year. There was 62% concordance between the original and the second-opinion diagnosis, with diagnostic discrepancy in 38%. The largest group of soft tissue neoplasms received for second opinion was fibroblastic/myofibroblastic tumors, and most major diagnostic problems were encountered in adipocytic and so-called “fibrohistiocytic” tumors. Major diagnostic errors impacting management were found in 148 cases (25%). Morphologic assessment of tumors, judicious use of molecular techniques, newer immunostains and their interpretation, along with importance of knowledge of rarer entities were found to be most useful in avoiding errors.

Idiopathic renal replacement lipomatosis is a rare condition in which the renal parenchyma, especially the renal sinus is replaced with adipose tissue with increase in perirenal fat. We report a case of renal replacement lipomatosis presenting as a renal mass clinically. The computed tomography scan revealed low density and nodular masses of adipose tissue within the renal parenchyma. The differential diagnosis before surgery was angiomyolipoma, lipoma, and xanthogranulomatous pyelonephritis. After the histological examination and extensive literature search, the diagnosis of renal replacement lipomatosis was made. It is a rare entity and may be missed if not considered due to lack of experience, so we hope that more urologists, radiologists, and pathologists become aware of this entity and recognize it.