Morbidity and Mortality

Advances in diagnosis and treatment have resulted in a drastic reduction in mortality related to brain abscess. Mortality rates of 50% were once commonplace but are now the exception rather than the rule. The reduction in mortality can be attributed to a number of factors. Advances in diagnostic imaging, most importantly the introduction of CT, have led to earlier diagnosis and treatment before neurological deterioration has occurred. Improved microbiological isolation techniques have dramatically reduced the incidence of negative cultures and significantly increased isolation rates of anerobic organisms. More effective antibiotics have become available, which have improved the treatment of Gram-negative and anerobic infections. Finally, the evolution of stereotactic image-guided techniques for aspiration of abscess contents has provided a simple and safe alternative to open surgery techniques.

Notwithstanding, brain abscess remains a serious illness that can result in death if misdi-agnosed or managed improperly. The risk of death is directly related to the rapidity of progression and, most importantly, the neurological condition of the patient at the time of diagnosis. Patients who are alert at diagnosis have a mortality rate of around 20%. In sharp contrast, the mortality rate for patients who present with signs of herniation exceeds 60% and, for those in coma, it is around 90%. Other factors that might influence mortality include virulence of the organism, etiology of the abscess, size, the presence of multiple abscesses and intraventricular rupture. Abscesses of sinusitic or otogenic origin tend to have a better prognosis than do metastatic abscesses, which are more frequently deep-seated and multiple. The most important factor that appears to contribute to increased mortality is delay in diagnosis. Also, with recent trends towards non-surgical management, there may be an inappropriate delay in operative intervention that might otherwise prevent herniation or intraventricular rupture, which may prove fatal.

Even successfully treated brain abscesses can result in long-term neurological sequelae and disability, primarily related to seizures, cognitive dysfunction and focal neurological deficits

[13,14]. Epilepsy is a common sequel of brain abscess, the incidence ranging from 30% to over 70%. The incidence may be influenced by several factors, including the presence of seizures prior to surgery, age at diagnosis, location of the abscess and choice of surgical procedure. Most patients who develop seizures pre-operatively go on to develop late epilepsy. Older patients generally have a shorter seizure-onset latency, with 50% suffering their initial seizure within 1 year of diagnosis. Although it has been suggested that seizure risk may be related to abscess location, this has not been substantiated. Finally, many series report a trend towards reduction in seizures in patients treated with aspiration as opposed to excision. Given the high incidence of seizures, it should probably be standard practice to place all patients with supratentorial brain abscesses on prophylactic anti-epileptic medications (AED). The AEDs should be continued for 1-2 years, following which they may be tapered, providing the EEG shows no epileptogenic activity.

Permanent neurological disability occurs in up to 50% of patients following treatment of brain abscess, most often the result of residual focal deficits or due to cognitive deficits, the latter particularly common in children [14]. The most important factors that influence long-term neurological outcome are age and abscess location. The incidence of focal deficits such as hemiparesis tends to be higher and more incapacitating in children. Morbidity is also higher in children, owing to the high incidence of abscesses caused by Proteus and Citrobacter, which are notorious for inducing a fulminant necrotizing reaction, with destruction of large amounts of brain parenchyma. Consequently, early aspiration is especially important in neonates and young children. The literature also suggests that permanent deficits may be more likely with excision than aspiration.

Recurrence occurs in 5-10% of cases, in spite of what is considered adequate therapy. Most recurrences become apparent within 6 weeks following therapy, although some have been reported many years following therapy. Reasons for recurrence include inadequate antibiotic therapy, incorrect choice of antibiotics, failure to aspirate large abscesses, presence of a retained foreign body or dural fistula and failure to eradicate underlying sources of infection.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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