Rakesh Kumar Vasishta

Non‐cirrhotic portal fibrosis (idiopathic portal hypertension): Experience with 151 patients and a review of the literature

Background: Non‐cirrhotic portal fibrosis (NCPF), the equivalent of idiopathic portal hypertension in Japan and hepatoportal sclerosis in the United States of America, is a common cause of portal hypertension in India. The clinical features, portographic and histological findings, and management of 151 patients with non‐cirrhotic portal fibrosis are presented.

N-acetylcysteine inhibits hyperglycemia-induced oxidative stress and apoptosis markers in diabetic neuropathy.

J. Neurochem. (2010) 112, 77–91.

Zygomycotic necrotizing fasciitis in immunocompetent patients: a series of 18 cases

Necrotizing fasciitis is most often associated with bacterial infections. Zygomycosis is an uncommon infection causing necrotizing fasciitis. We report 18 such cases of zygomycotic necrotizing fasciitis, of these, 15 were immunocompetent. Of the eight cases cultured, five were positive for Apophysomyces elegans. A retrospective case review conducted at a tertiary referral center, from 1998 to 2004, 18 cases of fungal necrotizing fasciitis were diagnosed based on histomorphology of fungal organisms; and in few of the cases diagnosis was supported by mycologic culture reports. Of the total of 18 cases, culture report was available in eight cases, and out of which five of them grew A. elegans. Fifteen patients were immunocompetent. Clinical presentation, mycologic findings and histopathologic results were evaluated. A review of the literature pertaining to A. elegans infection was also done. Histopathologic examination showed broad, predominantly aseptate and occasional pauciseptate, thin-walled fungal hyphae with occasional angioinvasion. To the best of our knowledge, this is the first largest series of zygomycotic necrotizing fasciitis from India. Herein, we present data on 18 cases of necrotizing fasciitis assosiated with zygomycosis. Most of the cases in our series were immunocompetent. Nonsuppurative necrosis with presence of typical fungal profiles was important histologic feature. Zygomycosis must be considered in the differential diagnosis not only in immunocompromised patients but also in the absence of any underlying disorders.

Adamantinoma: A clinicopathological review and update

Adamantinoma is a primary low-grade, malignant bone tumor that is predominantly located in the mid-portion of the tibia. The etiology of the tumor is still a matter of debate. The initial symptoms of adamantinoma are often indolent and nonspecific and depend on location and extent of the disease. Histologically, classic adamantinoma is a biphasic tumor characterized by epithelial and osteofibrous components that may be intermingled with each other in various proportions and differentiating patterns. To assure the histological diagnosis, pathologists should employ immunohistochemistry for demonstrating the sometimes sparse epithelial cell nests when the radiological features are suggestive of adamantinoma. There is paucity of compiled data over adamantinoma in the literature, hence authors tried to make a comprehensive review which must be of use to beginners and trained pathologists. Our objective is to further define the clinicoradiologic features and pathologic spectra of adamantinoma.

Role of fine needle aspiration cytology in the diagnosis of soft tissue tumours and tumour‐like lesions

In this study, we evaluated the usefulness of fine needle aspiration cytology (FNAC) in the diagnosis of soft tissue tumours. We have also assessed the various pitfalls of FNAC of soft tissue tumours. This was a retrospective study and here we analysed only 82 histopathology proven cases of FNAC of soft tissue tumours diagnosed in a five and half year period. On histopathological examination, 55 of these cases were malignant and 27 were benign. There was a total of 15 recurrences and histopathology was available prior to FNAC in only eight of these cases. Therefore, excluding these eight cases, malignant tumours were primarily diagnosed by FNAC in 47 cases. The sensitivity, specificity and positive predictive value of FNAC in diagnosis of soft tissue tumours were 91.5%, 92.5% and 95.5%, respectively. Only 22 of 47 cases (46.8%) were correctly categorized. There were two false‐positive and four false‐negative cases. One case each of fibromatosis and schwannoma were reported as sarcoma. False‐negative cases were fibrosarcoma (1), malignant nerve sheath tumour (2) and haemangiopericytoma (1). FNAC was very useful in distinguishing benign from malignant soft tissue tumours. However, it was not so effective in exact categorization of tumours.

Pulmonary Embolism in Medical Patients: An Autopsy-Based Study

Pulmonary embolism, though treatable, is a devastating disease and an important cause of morbidity and mortality among hospitalized patients. In all, 1000 autopsies were reviewed in adult medical patients. The overall incidence of pulmonary embolism in adult medical autopsies was 15.9% (159/1000). The incidence of pulmonary embolism contributing significantly to the death of the patients (groups 1 and 2) is 126/1000 (12.6%). Thus, pulmonary embolism very significantly contributed to death in 126/159 (79.24%) of group 1 and 2 patients. Pulmonary embolism affected a younger population as 79.87% of the overall patients, 66.67% of the fatal cases (group 1) and 73% of combined group 1 and 2 cases were below the age of 50 years. Sepsis was the primary diagnosis in 32% of total and in 42% of fatal cases. Hence, pulmonary embolism is considered as an important cause of death in patients admitted to the medical wards. It affects a younger population in India and needs to be tackled appropriately.

Pulmonary Capillary Haemangiomatosis as a Cause of Pulmonary Hypertension in Takayasu’s Aortoarteritis

Pulmonary hypertension is known to occur in Takayasus aortoarteritis. It may be either due to pulmonary arterial involvement or elevated left ventricular end diastolic pressure, or both. In our case, the cause of pulmonary hypertension was a recently described rare lesion termed pulmonary capillary haemangiomatosis. This entity has a very distinct histopathologic picture. Although 19 cases have been reported in the English literature, this is the first report on pulmonary capillary haemangiomatosis producing pulmonary hypertension in Takayasus aortoarteritis.

Vaccination with a novel recombinant Leishmania antigen plus MPL provides partial protection against L. donovani challenge in experimental model of visceral leishmaniasis.

The acquisition of immunity following subclinical or resolved infection with the intracellular parasite Leishmania donovani suggests that vaccination could prevent visceral leishmaniasis. The characteristics and in vitro stimulating capability of the recombinant proteins expressed by previously identified clones on the basis of their capacity to stimulate an indigenously established Leishmania-specific cell line leading to high level of IFN-gamma suggested these to be potential candidates for immunoprophylaxis against leishmaniasis. In this study, we investigated the protective efficacy of purified recombinant proteins from two of the identified cDNA clones along with the adjuvant MPL, in a hamster model of experimental leishmaniasis. We demonstrate here that the immunization of animals with one of the recombinant proteins (rF14) having 97% similarity to C1 clone of L. chagasi ribosomal protein gene P0 (rLiP0) along with MPL provided partial protection against the virulent challenge of L. donovani. The absence of antigen-specific lymphoproliferative responses in these immunized animals may be responsible for the lack of complete and long-lasting protection.

Central nervous system complications in renal transplant recipients in a tropical environment.

Renal transplant recipients are at risk of developing various infectious and non-infectious complications affecting the central nervous system (CNS). There is paucity of data regarding the spectrum of CNS complications and the epidemiology of infective agents varies according to geographical location. We retrospectively studied the spectrum of CNS complications seen in 792 renal allograft recipients followed up at this tertiary care centre in north India over a 19-year period. Autopsy findings of 78 allograft recipients who died in the hospital were also reviewed and included. The brain was examined in 22 of these patients. Overall, 79 (10%) patients developed some form of CNS dysfunction with a mortality rate of 60.8%. CNS infections occurred in 31 renal allograft recipients (3.9% of total) and accounted for the largest group (39.2%). Fungi were the commonest etiological agents (21 patients) and were associated with a 70% mortality, with cryptococcal meningitis occurring in 12, mucormycosis in six, aspergillosis in one, and other unusual fungal infections in the remaining two patients. All patients with mucormycosis had a fatal outcome. The second largest group comprised of patients with non-uremic encephalopathies (23 patients, 29.1%) with metabolic encephalopathy occurring in 13, toxic encephalopathy in nine and hypertensive encephalopathy in one patient) and was associated with an overall mortality rate of 60.9%. Cerebrovascular accidents occurred in 12 patients (15.2%) and were associated with a mortality of 91.7%. Other CNS complications included treatment related complications in four (5.1%), primary CNS lymphomas in three (3.8%), and miscellaneous complications in six patients (7.6%). Patients with non-cryptococcal fungal infections of the CNS, hepatic and toxic encephalopathy and those with cerebrovascular accidents had the worst outcome. There was no relationship between the development of infection or stroke and the type of maintenance immunosuppression used. We conclude that complications involving the CNS occur in 10% of all renal transplant recipients and are associated a with high mortality, warranting early diagnosis and aggressive treatment.

Aseptic cerebral venous thrombosis associated with idiopathic ulcerative colitis: a report of two cases

Two cases of cerebral venous thrombosis with ulcerative colitis with complete autopsy findings are reported. The diagnosis of cerebral venous thrombosis with ulcerative colitis was made during life in one case and at autopsy showed active chronic ulcerative colitis with recent cerebral venous thrombosis with cerebral infarction. In the other case active chronic ulcerative colitis and old cerebral venous thrombosis with cerebral infarction were diagnosed at autopsy. Although rare the importance of recognising cerebral venous thrombosis as a complication of ulcerative colitis has been emphasised in view of the high mortality of this complication.