The Role of Estrogen Therapy as a Protective Factor for Alzheimer's Disease and Dementia in Postmenopausal Women: A Comprehensive Review of the Literature.

The complete cessation of menstruation for 12 months with associated vasomotor symptoms is termed menopause. Apart from playing a role in reproduction, estrogen significantly affects the central nervous system (CNS). Population-based studies highlighted a substantial difference in the prevalence of dementia between men and women, with Alzheimer-associated dementia being more prevalent in women, indicating that estrogen deficiency might be a risk factor for neurodegenerative diseases. Patients with dementia experience a progressive decline in neurocognitive function, beginning with short-term memory loss that progresses to long-term memory loss and the inability to perform everyday activities, leading ultimately to death. There is currently no cure for dementia, so preventing or slowing the disease's progression is paramount. Accordingly, researchers have widely studied the role of estrogen as a neuroprotective agent. Estrogen prevents dementia by augmenting Hippocampal and prefrontal cortex function, reducing neuroinflammation, preventing degradation of estrogen receptors, decreasing oxidative damage to the brain, and increasing cholinergic and serotonergic function. According to the window phase hypothesis, estrogen's effect on preventing dementia is more pronounced if therapy is started early, during the first five years of menopause. Other studies like The Woman's Health Initiative Memory Study (WHIMS) showed unfavorable effects of estrogen on the brain. This review aims to establish an understanding of the currently available data on estrogen's effect on neurodegeneration, namely, dementia and Alzheimer's disease.

Retraction: Listerial Meningitis and Brain Abscess With Coexisting COVID-19 Infection in a Young, Immunocompetent Male: A Case Report.

[This retracts the article DOI: 10.7759/cureus.29455.].

Listerial Meningitis and Brain Abscess With Coexisting COVID-19 Infection in a Young, Immunocompetent Male: A Case Report.

Listeria monocytogenes (LM) is a gram-positive intracellular pathogen that can cause central nervous system infections such as meningitis, meningoencephalitis, rhombencephalitis, or cerebritis. It rarely causes a brain abscess. Listerial meningitis and brain abscess most commonly occur in immunocompromised individuals, neonates, pregnant females, alcoholics, and the elderly. We present a unique case of a young immunocompetent male who presented with listerial meningitis and brain abscess. Coexisting coronavirus disease 2019 (COVID-19) infection was also present. Since LM was not included in the differentials, the standard antibiotic regimen started for the meningitis therapy was ineffective. Remdesivir was administered to treat the coexisting COVID-19 infection. When the lumbar tap polymerase chain reaction pointed out that the causative agent was Listeria, we shifted to ampicillin and gentamicin therapy, to which the patient responded very effectively.LM is an atypical cause of meningitis and brain abscesses. A high index of suspicion is therefore required for early detection and effective treatment of listerial meningitis and brain abscess.