Neurosyphilis: A Monkey Among Men.

Neurosyphilis is the progression of the untreated sexually transmitted infection caused by Treponema pallidum. When the initial infection is not adequately treated, progression of primary syphilis can lead to a wide variety of serious health sequelae. While neurosyphilis can appear up to 10-30 years after the initial infection, syphilis can invade the nervous systemat any stage of infection and can imitate symptoms of many other diseases. This variety of symptoms is why syphilis has been called "The Great Pretender" or "Themonkey among diseases"(Krämer et al., 2018).12 This is a case report of an 83-year-old female with a history of multiple TIAs, dementia, and breast cancer who presented to the emergency department with complaints of her head "not feeling right" and intermittent ataxia (episodes of imbalance and difficulty ambulating) reported by patient and patients' son. Physical exam only pertinent for chronic shuffling gait, but no ataxia. The patient underwent further work-up, demonstrating negative brain imaging for cerebral vascular accident and laboratory findings negative initially, for acute infection. An RPR was drawn as part of an broadened altered mental status workup as the patient and family stated she was not back to baseline mental status and was positive with a quantitative titer of 1:8. Fluorescent treponemal antibody absorption (FTA-ab) was found to be positive as well. The patient was started on three million units intravenous Penicillin G every 4 h and was discharged with a peripherally inserted central catheter in order to receive two weeks of Rocephin at two grams daily. Patient returned to prior baseline following completion of treatment. Through this case, we hope to provide information on neurosyphilis and its differentiation from other disease processes and when neurosyphilis should be suspected during an evaluation of altered mental status.

An unusual case of severe hypercalcemia: as dehydrated as a bone.

Objective: Severe hypercalcemia is a medical emergency. Hyperparathyroidism, malignancy, vitamin D toxicity, infections such as tuberculosis, or systemic illness such as sarcoidosis are all possible etiologies. Among the less studied causes is dehydration. Our objective is to identify dehydration as an etiology of hypercalcemia. Methods: Extensive literature review did not recognize dehydration as an etiology of hypercalcemia. We present a case of dehydration leading to severe hypercalcemia in a 60-years-old female with a presentation of altered mental status and corrected calcium level of 19 mg/dL in the absence of parathyroid abnormality, vitamin D toxicity, systemic disease, or malignancy. Results: Dehydration caused hypercalcemia which led to a feed-forward mechanism and caused further worsening dehydration, worsening kidney function, and severe hypercalcemia. The patient responded very well to intravenous fluid and at the time of discharge had a serum calcium of 9.8 mg/dL with improved mental status back to the baseline. Conclusion: Our literature review demonstrated many causes of hypercalcemia, with dehydration being exceptionally rare. It is our hope that this case report may serve as evidence of one such instance, allowing providers to keep a working differential of dehydration in severely elevated calcium levels.

Behavioural and neural interactions between objective and subjective performance in a Matching Pennies game.

To examine the behavioural and neural interactions between objective and subjective performance during competitive decision-making, participants completed a Matching Pennies game where win-rates were fixed within three conditions (win > lose, win = lose, win < lose) and outcomes were predicted at each trial. Using random behaviour as the hallmark of optimal performance, we observed item (heads), contingency (win-stay, lose-shift) and combinatorial (HH, HT, TH, TT) biases across all conditions. Higher-quality behaviour represented by a reduction in combinatorial bias was observed during high win-rate exposure. In contrast, over-optimism biases were observed only in conditions where win rates were equal to, or less than, loss rates. At a group level, a neural measure of outcome evaluation (feedback-related negativity; FRN) indexed the binary distinction between positive and negative outcome. At an individual level, increased belief in successful performance accentuated FRN amplitude differences between wins and losses. Taken together, the data suggest that objective experiences of, or, subjective beliefs in, the predominance of positive outcomes may be mutual attempts to self-regulate performance during competition. In this way, increased exposure to positive outcomes (real or imagined) may help to weight the output of the more diligent and analytic System 2, relative to the impulsive and intuitive System 1.