Rhodococcus equi brain abscess in a patient without HIV.

Rhodococcus equi, a Gram positive organism, is a cause of infections in immunocompromised individuals. In humans, it mainly causes disease in those infected with human immunodeficiency virus (HIV), and generally presents as chronic pulmonary infection. It may also cause intracranial infections, which manifest as brain abscesses. This report describes a case of rhodococcus brain and pulmonary infection in a patient who did not have HIV or another disorder of cell mediated immunity. He was treated with intravenous imipenem, vancomycin, and rifampin for eight weeks and recovered from the infection.

Morphology and comparative anatomy of circulus arteriosus cerebri in mammals.

The normal configuration of the arterial pattern at the base of the brain in rhesus monkeys, dogs, sheep, goats and rabbits is described. The length and diameter of all vessels of the circulus arteriosus cerebri are measured. Variations are compared in relation to that of the typical pattern present in humans. In rhesus monkeys, dogs and rabbits, the circle of Willis is almost similar to that in human beings except that in these animals, (i) the anterior cerebral arteries join each other to form a single median vessel; (ii) in dogs, rabbits, goats and sheep the anterior cerebellar artery is a branch of posterior cerebral artery, and (iii) in goats and sheep, a considerable length of the internal carotid artery contributes to the formation of circulus arteriosus while the posterior cerebral artery arises from the posterior communicating artery.

Incidence of intracranial aneurysms in north-west Indian population.

One thousand human brains of both sexes were examined. Aneurysms were found in 10 specimens (1%). The incidence of aneurysms was 1.6% in females and 0.8% in males. All the aneurysms were saccular. The aneurysms varied in size. In 5 specimens the aneurysms were minute bulbous dilatations. In the rest of the cases it varied from 0.2 to 2.5 cm. In 7 specimens the aneurysms were present at the junction of anterior cerebral artery with the anterior communicating artery, in 2 on the anterior communicating artery and in one specimen it was seen at the origin of posterior communicating artery. The youngest subject with saccular aneurysm was an 18-years-old male and the oldest was a 55-years-old male. No aneurysm was found in the brains of 94 children (1-17 years).

Calvarial tuberculosis.

BACKGROUND: Calvarial tuberculosis is rare, even in areas where tuberculosis is endemic. Primary calvarial tuberculosis, with no evidence of tuberculosis elsewhere in the body is a rarer entity. METHODS: Seven cases of calvarial tuberculosis are presented. The relevant clinicoradiological features and management are discussed. RESULTS: Two cases of primary calvarial tuberculosis could only be diagnosed after surgery. The other cases were diagnosed with the help of fine needle aspiration cytology (FNAC) and biopsy. CONCLUSION: A high index of suspicion and awareness of this condition may lead to more cases being diagnosed early. Surgery may be avoided in selected cases that can be treated primarily with antitubercular therapy.

Primary central nervous system lymphoma: experience of 46 cases with review of literature.

Primary central nervous system lymphomas (PCNSL) constitutes only 1.0 to 1.5% of all brain tumors. Their incidence has gone up over tenfold in the last 25 years. Though, there has been an association of PCNSL with acquired immune deficiency syndrome (AIDS), yet the increased incidence of PCNSL appears to be real and unrelated to AIDS and organ transplantation. This increased incidence could be because of improvement in diagnostic technology and practice. The outcome remains gloomy despite surgical resection, radiotherapy and intensive adjuvant chemotherapy regimens, as majority of the patients succumb to the disease, with only 30-40% survival in patients under 70 years of age.

Aminoglycoside resistance genes aph(2")-Ib and aac(6')-Im detected together in strains of both Escherichia coli and Enterococcus faecium.

Escherichia coli SCH92111602 expresses an aminoglycoside resistance profile similar to that conferred by the aac(6')-Ie-aph(2")-Ia gene found in gram-positive cocci and was found to contain the aminoglycoside resistance genes aph(2")-Ib and aac(6')-Im (only 44 nucleotides apart). aph(2")-Ib had been reported previously in Enterococcus faecium SF11770. aac(6')-Im had not been detected previously in enterococci and was found to be present also 44 nucleotides downstream from aph(2")-Ib in E. faecium SF11770. aph(2")-Ib and aac(6')-Im are separate open reading frames, each with its own putative ribosome binding site, whereas aac(6')-Ie-aph(2")-Ia appears to be a fusion of two genes with just one start and one stop codon. The deduced AAC(6')-Im protein exhibits 56% identity and 80% similarity to the AAC(6')-Ie domain of the bifunctional enzyme AAC(6')-APH(2"). Our results document the existence of a member of the aph(2") family of genes in gram-negative bacteria and provide evidence suggesting the horizontal transfer of aph(2")-Ib and aac(6')-Im as a unit between gram-positive and gram-negative bacteria.

Flowcytometric and histopathological correlation of primary intracranial neoplasms.

DNA ploidy and synthetic phase fraction (SPF) of 52 cases of primary intracranial neoplasms have been determined from fresh tissues and the data was correlated with histopathological typing and grading. Fresh tumour tissues from 52 random surgical biopsies (28 malignant and 24 benign) were obtained from neurosurgical operations during the period 1994-1996. The cells were analysed in Becton Dickinson flowcytometer fitted with Consort 30 programme and 'Sober' software. Percentage of diploid cells, proliferative cells and DNA aneuploidy were evaluated. The tumours were classified and graded according to WHO classification (1993). On histology, there were 28 malignant (grade II to IV) and 24 benign cases (grade I). All the histologically benign tumours in this study showed diploid DNA content with the exception of a pituitary adenoma which had a heterogeneous population of cells. The S phase fraction in all the benign cases was less than 10% except in the case of choroid plexus papilloma (S-phase 54%) and an atypical meningioma (S-phase 14%). Out of the 28 malignant tumours, 12 cases were aneuploid (43%) and the rest were diploid (57%). Among the 16 diploid tumours, SPF was more than 10% in eight cases. DNA aneuploidy and high SPF are more common in histologically malignant tumours than benign tumours. SPF is a reflection of proliferation potential of a tumour and may have some role in prognostication of brain tumours.

Ideal ward round making in neurosurgical practice.

The success of a perfect ward round lies in the role of the consultant leading the 'round making group' (RMG) as well as the hallmark of effective questioning and participation of each member. Twelve senior consultants with more than 10 years' experience in neurosurgical practice at three different university hospitals were observed during round making by a participant observer. Observations were made on the group climate of the RMG, the leadership pattern and language expressed by the clinician conducting the round and the effectiveness in his performance as a leader during clinical discussions. The group climate showed evidence of good productivity and flexibility with 92% and 75% consultants, pleasantness of climate was above average with only 50% (6/12) and poor objectivity with 42% (5/12) consultants. Forty two percent of the consultants were not always very well comprehensible, while only 50% (6/12) spoke exactly fitting the occasion. Only 33% (4/12) of the consultants used humour effectively, while 42% (5/12) spoke unnecessarily in between discussion and were poor in introducing the problems of patient to the round making group. Ward round making in neurosurgical practice needs a holistic approach with motivation, planning, leadership skills and structured curriculum to fulfill its objectives.

Histopathological and biochemical changes in the sutural region in craniosynostosis.

OBJECT: Histopathological observations and biochemical analysis of sutural bones in nine patients with craniosynostosis were compared with control subjects of the same age range. METHODS: Microscopic examination in craniosynostosis showed formation of an active osseous front, with higher osteoblastic activity than in controls. Biochemical analysis revealed higher calcium, phosphorus, alkaline phosphatase, phospholipids and chondroitin sulphate-A contents in sutural bones of the same patients. CONCLUSIONS: The present study systematically establishes a premature increase in osteogenesis in the sutures of craniosynostosis patients.

In-vitro synergistic activity of the combination of ampicillin and arbekacin against vancomycin-and high-level gentamicin-resistant Enterococcus faecium with the aph(2")-Id gene.

The combination of ampicillin plus arbekacin produced synergistic killing against 8 of 13 vancomycin-, ampicillin-, gentamicin-, and streptomycin-resistant Enterococcus faecium isolates that possess the high-level gentamicin resistance gene, aph(2")-Id. This combination may prove useful in treating infections caused by multiresistant enterococci.

Efficacy of ampicillin plus arbekacin in experimental rabbit endocarditis caused by an Enterococcus faecalis strain with high-level gentamicin resistance.

Enterococcus faecalis LC40 is an ampicillin-susceptible clinical isolate with high-level gentamicin resistance due to the aac(6')-Ie-aph(2")-Ia aminoglycoside resistance gene. The combination of ampicillin plus arbekacin reduced mean bacterial vegetation counts significantly more than ampicillin alone or ampicillin plus gentamicin in a rabbit model of aortic-valve endocarditis caused by E. faecalis LC40.

Treatment of HIV disease in the new millennium.

Highly active antiretroviral therapy (HAART), which typically consists of 3-drug combinations of antiretroviral agents, has decreased dramatically the incidence of AIDS and death among HIV-infected persons in the United States. HIV infection no longer is viewed as a death sentence. Complete suppression of viral replication through the use of HAART can reverse the immune deficits formerly thought to be inevitable. However, drug toxicity, cross-resistance, and less-than-perfect adherence to prescribed antiretroviral regimens make the medical management of the HIV-infected person complex. An overview of the current approach to antiretroviral therapy is presented in this article.

Clinically and biochemically silent thyrotroph adenoma with oncocytic change.

A case of clinically and biochemically silent pituitary tumour with ultrastructural and immunohistochemical evidence of thyroid stimulating hormone secretion is presented. Significance of recognition of such silent tumours is discussed.

Suprasellar malignant mixed germ cell tumour presenting as craniopharyngioma.

A 15 year old boy presented with diminution in vision of both eyes, diabetes insipidus and hypopituitarism. MRI was suggestive of a large suprasellar and retrosellar craniopharyngioma with stretching of the optic chiasma. Histopathological findings on the first surgical specimen were interpreted as a craniopharyngioma. He was reoperated on account of clinical deterioration and increase in tumour size. Histological examination this time revealed derivatives of all three germ cell lineages along with areas of embryonal carcinoma, and yolk sac tumour besides squamous cysts, establishing the diagnosis of malignant mixed germ cell tumour. Serum and CSF were strongly positive for alpha foetoproteins.

A mathematical outcome prediction model in severe head injury: a pilot study.

103 patients of head injury, with a Glasgow coma scale (GCS) score of 8 or less, were studied prospectively. GCS score, brain stem reflexes, motor score, reaction level scale, and Glasgow Liege scale were evaluated as prognostic variables. Linear logistic regression analysis was used to obtain coefficients of these variables and mathematical formulae developed to predict outcome in individual patients.

Pituitary adenoma and parasagittal meningioma: an unusual association.

Simultaneous detection of an intracranial meningioma with a pituitary tumour prior to radiotherapy is an extremely uncommon occurrence. Authors have managed an elderly acromegalic lady with an acidophilic pituitary adenoma, who also harboured an asymptomatic anterior third parasagittal meningioma. There were no features of neurofibromatosis. Both tumours were concurrently excised.

Intracranial pressure changes with different doses of lignocaine under general anaesthesia.

The effect of intravenous lignocaine on intracranial pressure (ICP) was studied on thirty patients of either sex, aged above 5 years and scheduled for elective ventriculoperitoneal shunt surgery. The patients were randomly divided into 3 groups, which received intravenous lignocaine in the dose of 1 mg, 1.5 mg and 2 mg/kg body weight respectively. Intracranial pressure, heart rate, ECG, arterial pressure and arterial blood gases were monitored at various intervals for a period of 30 minutes. Maximum decrease in ICP was seen at 2 minutes after IV lignocaine in all the three groups (p<0. 001). The fall in ICP was significantly more in group II and group III (35.65% and 37.5% respectively) as compared to group I (17.47%) (p<0.001). This fall in ICP in all the three groups persisted below the basal level, throughout the study period. None of the groups showed any significant change in the heart rate, but a statistically significant fall in arterial pressure was observed in group III (p<0. 05). In conclusion intravenous lignocaine, in a dose of 1.5 mg/kg, causes significant fall in ICP without causing any untoward cardiovascular effects and is recommended for routine clinical use.

Suprasellar arachnoid cyst presenting with precocious puberty : report of two cases.

Suprasellar arachnoid cysts (SSAC) are uncommon intracranial lesions. Two patients of SSAC presenting with precocious puberty are described. In both the cases partial excision of the cyst wall, through a pterional craniotomy, establishing communication with the basal subarachnoid spaces was carried out. The endocrinological symptoms regressed after surgery. The clinical presentations of SSAC and the treatment options available are reviewed.