Fatal rhino-orbito-cerebral infection caused by Saksenaea vasiformis in an immunocompetent individual: first case report from India

A 56-year-old female patient presented with history of nasal blockage, nasal bleeding, headache, since one month. On admission the patient developed severe headache, decreased vision of eyes and blindness. Clinical diagnosis of rhino-orbital involvement was confirmed by computerized tomography of the paranasal sinuses. The diagnosis of fungal infection was confirmed by KOH examination, haematoxylin and eosin examination and Gomori's methanamine silver stain of the biopsy material. Diagnosis was confirmed by culture on Sabouraud Dextrose agar, slide culture on Czapek Dox medium and the isolate was identified as Saksenaea vasiformis. The patient was started on intravenous amphotericin B (received only one dose before succumbing), but she did not respond to the treatment, developed hemiparesis, slurred speech, diminished reflexes and ultimately died. The involvement of the brain was confirmed by computerised tomographic scan. We believe this case to be the first case of rhino-orbito-cerebral infection due to Saksenaea vasiformis and that of second case in an immunocompetent patient in the world.     

Features of sentinel lymph nodes for melanoma may lead to re-diagnosis of the cutaneous primary: an unusual case and review of literature

Although sentinel lymph-node biopsy is accepted as a reliable method of staging of melanoma, it is not without problems to the pathologist. It has been re-emphasised that aggregates of benign naevus cells are not uncommon. Usually these are easily identified by a combination of their benign cytology and location in the fibrous skeleton of lymph nodes. This case represents a combination of an unusual pseudo-malignant pattern in the primary lesion with unusual morphology of the sentinel lymph node. The latter prompted reassessment of the cutaneous lesion as a benign naevus. Confirmation of the diagnosis as cutaneous melanoma by a positive sentinel-node biopsy was averted only by a careful comparison of unusual features of the putative primary and the sentinel lymph node. This case illustrates the need for a rigorous protocol for pathological assessment of sentinel lymph nodes for melanomas to assure detection of all metastases but also to avoid misdiagnosis and over-treatment. It also supports benign metastases as the mechanism underlying at least some melanocytes in regional lymph nodes.     

Dengue vaccine: The current status

Dengue fever is a re-emerging public health problem with two-fifths of the world population being at risk of infection. Since there are no antiviral drugs available against the dengue virus, and vector control programmes have been largely unsuccessful in preventing outbreaks, vaccination seems to be the most viable option for preventing infection. An ideal dengue vaccine should provide long lasting immunity against all four serotypes of the virus. The envelope protein of the virus plays a key role in vaccine development. The present day candidate vaccines includes a live attenuated tetravalent vaccine, intertypic chimaeric vaccines based on live attenuated dengue virus vectors, chimaeric vaccines based on the live attenuated Yellow Fever 17D vector and recombinant vaccines which include vaccines based on flavivirus and non-flavivirus vectors. Tetravalent live attenuated vaccines, intertypic chimaeric vaccines and chimaeric vaccines are being tested in human trials. Recombinant DNA vaccines based on flavivirus and non-flavivirus vectors are being tested in animal trials. Recent studies have shown that the tetravalent formulations may elicit an unbalanced immune response. Research is continuing to find means of obtaining a balanced response to all antigens in the tetravalent formulations.