**1.1.5 Neurosalmonellosis**

308 Novel Aspects on Epilepsy

a novel influenza virus into the human population will result in a pandemic. (Lee & Saif, 2009) Epilepsy is not a known complication in this group and its presence suggests

Slow virus infections are also known as prion diseases. Prions are proteinaceous infectious particles (PrPs). The brain pathology of prion diseases consists of a vacuolar (spongiform) degeneration of the neuropil, cortical neurons, and subcortical gray matter with neuronal loss and gliosis. Early diagnosis is difficult, in part because prions do not have nucleic acids, making conventional nucleic acid–based viral detection systems ineffective. PrPs also elude detection by not producing a humoral immune response (Johnson & Gibbs, 1998) As part of this group is: bovine spongiform encephalopathy (BSE) which is thought to have originated in Great Britain where it was first observed (April 1985) and was officially diagnosed. Control measures have since reduced incidence of the disease, and currently fewer than 100 new cases are reported per week. It occurs in cattle between two and eight years old and is always fatal. A transmissible spongiform encephalopathy of adult cattle, transmitted by feed containing protein in the form of meat and bone meal derived from infected animals. Affected adults may have seizures as part of the serious neurological illness. Renkawek et al (1992), hypothesized that a defect of Na+/K+ -ATPase of the astrocytes could be the most common

pathogenetic factor for the congenital convulsive status and for the spongy state.

Cellular prion protein (PrPc) plays an essential role in maintaining neurotransmitter homeostasis in the central nervous system. This discovery has been made possible by the observation that both a deficiency and an excess of the protein have a considerable effect on this homeostasis. Surprisingly, in both cases, the central nervous excitability threshold is altered to such an extent that an epileptic seizure may result. Thanks to this discovery, we now have more tools at our disposal that can help us to deepen our basic understanding of

As under normal conditions the protein is found in adequate concentrations, it was expected that greater amounts of PrPc would provide greater protection against seizures. Surprisingly, however, the study showed that this is not the case. With an excessive amount of the protein, the level of excitability of the central nervous system is increased even more than in the absence of PrPc, due to the fact that both the excitatory and inhibitory mechanisms are altered. Such alterations further increase the possibility of suffering severe epileptic seizures. The protein, when present at adequate concentrations, is essential for maintaining neurotransmitter homeostasis or equilibrium in the central nervous system. The researchers of IBEC who participated in the study are currently involved in developing a description of the possible differences in the expression and modification of the cellular

Brucellosis is a major ubiquitous zoonosis transmitted from livestock to humans. It is a public health problem in developing countries. The estimated mean incidence of neurobrucellosis is 4% with clinical manifestations that are variable and often multi-focal in

Neurobrucellosis is a rare form of systemic brucellosis, a disease acquired through ingestion of unpasteurized dairy products, it can affect any part of the nervous system and can mimic any neurological disease which may manifest as stroke, encephalitis, meningitis, or

reviewing the clinical diagnosis.

**1.1.3 Slow virus infections** 

epilepsy. (IBEC, 2009)

**1.1.4 Neurobrucellosis** 

prion protein in epileptic patients. (IBEC, 2009)

the same patient. (Guenifi et al., 2010)

*Salmonella* serotypes *typhi, typhimurium*, and *enteritidis* occurred most frequently. The precipitating factors of these infections included meningitis, trauma, and intracranial hematoma. Focal intracranial infections are unusual manifestations of salmonellosis. In one hundred years only 43 such infections have been reported in the world literature. Brain abscess occurred more often in adults; in contrast, subdural empyema presented more often in children and fever, signs and symptoms of increased intracranial pressure, change in mental status, seizures, and focal neurologic deficits were the commonest clinical features.(Rodriguez et al,. 1986)
