Altered Mental Status
Particularly in summertime, heat stroke is a significant cause of presentation of altered mental status. Heat stroke (or sunstroke) is a medical emergency that can prove to be fatal if not dealt with promptly and it is believed to be an inflammatory response to excessive heat (Pinto, Walsh & Pravikoff, 2011) Classic heat stroke occurs independent of exertion in heat; exertional heat stroke is the result of high physical activity levels (Pinto et al., 2011). The diagnosis of classic heat stroke often occurs in older adults (older than 65 years) who have a chronic illness such as diabetes, hypertension, cardiomyopathy, pneumonia, or some other neuological or psychological disease (Pinto et al., 2011). Exertional heat stroke can occur in ambient temperatures that are high, normal, or even cold (Pinto et al., 2011). The three key symptoms for diagnosis include a body temperature above 106 F (41.1 C), altered mental status (confusion, agitation, ataxia, coma, or seizures), and recent exposure to excessive heat (Pinto et al., 2011). Other symptoms may include lack of sweating (though in exertional heat stroke sweating may continue), cardiac arhythmias, hyperventilation, shock, anorexia, dizziness, fatigue, and nausea (Miners, 2010).
Another common cause of presentation of altered mental status is alcohol abuse. The current DSM-IV criteria for a diagnosis of alcohol abuse include using alcohol in a hazardous manner (for example, drinking and driving, swimming while under the influence, etc.), alcohol use that interferes with fulfilling significant obligations to work or family, alcohol use that interferes with interpersonal relationships, and alcohol use that generates legal problems. If any of these four criteria are met, a diagnosis of alcohol abuse can be made (Keyes & Hasin, 2008). These criteria are relatively independent of socio-economic status, though the hazardous use criteria most often involves individuals wealthy enough to own or have access to a car (Keyes & Hasin, 2008). Recent evidence indicates that alcohol dependence and alcohol abuse are part of the same continuous spectrum rather than completely separate disorders, though the threshold for the two is not clear (Slade, Grove & Teesson, 2009). In terms of sociological issues, college students drink and are more likely to be diagnosed with alcohol abuse than others of that age group, but overall, college graduation correlates with a lower lifetime rate of alcohol abuse (Keyes & Hasin, 2008).
Bacterial meningitis is a third cause of altered mental status. Bacterial meningitis is potentially fatal, but less common that aseptic (viral) meningitis (Bamberger, 2010). For community acquired bacterial meningitis, risk factors can include recent ear infections (otitis) or sinusitis, pneumonia, or have some compromise of their immune system (Bamberger, 2010). Meningitis displays symptoms including at least two of fever, neck stiffness, altered mental status, and headache; white blood cell count in the cerebrospinal fluid of at least 100 per microliter; and nausea (Bamberger, 2010). Older adults with bacterial meningitis are more likely to have seizures and hemiparesis, but less likely to have headaches, nausea and vomiting (Bamberger, 2010). Young children, on the other hand, are much less likely to present the common symptoms and more likely to have lethargy and irritation; recent respiratory tract infections are also more often precursors in children (Bamberger, 2010). Unfortunately, because the symptoms are nonspecific, a cerebrospinal fluid check is important and many such cases will turn out to be other diseases than bacterial meningitis. Still, in young children, a normal white blood count does not rule out bacterial meningits (Bamberger, 2010).