Central Nervous System Infections

Bell Palsy

Description of Medical Condition Paralysis or weakness of the muscles supplied by the facial nerve, typically unilaterally, due to inflammation and swelling of the facial nerve within the facial canal Bell palsy: Idiopathic Ramsay Hunt syndrome: Bell palsy associated with vesicles within the outer ear canal or behind the ear. due to herpes zoster infection Facial diplegia: The simultaneous development of bilateral Bell palsy is highly unusual and conditions such as Guillain-Barre syndrome and chronic meningitis should be considered as possible explanations. System(s) affected: Nervous Genetics: There is a familial tendency toward Bell palsy Incidence/Prevalence in USA: Incidence 16 in 100,000 Predominant age: Affects all ages. Most common in individuals over […]

Assessment of Fever

Relevant Evaluation Criteria Scenario/Model Outcome Information Gathering 1. Gather essential information about the patient’s symptoms, including: a. description of symptom(s) (i.e., nature, onset, duration, severity, associated symptoms) Child daycare provider reported to parents that their daughter has felt warm and is not eating well, although she continues to play with the other children. They took an oral temperature, which was 101.4°F. They did not notice any other symptoms other than a slight runny nose. b. description of any factors that seem to precipitate, exacerbate, and/or relieve the patient’s symptom(s) The parents have not tried anything up to this point. c. description of the patient’s efforts to relieve the symptoms None reported […]

Intravascular Catheter-Related Infections

Potential Severity Can be life-threatening. Often prolong hospital stay, and can be complicated by metastatic lesions and bacterial endocarditis. Case 2 A 53-year-old white woman was admitted to the hospital with complaints of severe shaking during infusion of her hyperalimentation solution. She had been receiving intravenous hyperalimentation for 16years for a severe dumping syndrome that prevented eating by mouth. She had had multiple complications from her intravenous lines, including venous occlusions and line-associated bacteremia, requiring 24 line replacements. She had last been admitted 6 months earlier with Enter-obacter cloacae infection of her intravascular catheter requiring line removal andintravenous cefepime. Atthat time, a tunneled catheter had been placed in her leftsub-clavian vein, […]


Potential Severity Fulminant myocarditis can be fatal or lead to chronic congestive heart failure. Most cases are self-limiting and are followed by full recovery The true incidence of myocarditis (inflammation of the heart) is unknown, because most cases are asymptomatic. It has been estimated that 1% to 5% of systemic viral illnesses have myocardial involvement. Young males are at higher risk for serious myocarditis, as are pregnant women, neonates, and immunocompromised patients. Causes and Pathogenesis Viruses are a major cause of myocarditis, and specific causation has been identified by Polymerase chain reaction in nearly 40% of patients with myocarditis. Adenoviruses and enteroviruses (Coxsackievirus В and echoviruses) are most commonly detected, but […]

Central Nervous System Infections

Potential Severity Often life-threatening, infections of the central nervous system are infectious disease emergencies. They require immediate treatment. Central nervous system  infections are fortunately rare, but they are extremely serious. The cerebral cortex and spinal cord are confined within the restricted boundaries of the skull and boney spinal canal. Inflammation and edema therefore have devastating consequences, often leading to tissue infarction that in turn results in permanent neurologic sequelae or death. To understand the pathogenesis and clinical consequences of Central nervous system infections, a working knowledge of basic neuroanatomy and neurophysiology is important. The cerebral cortex and spinal cord are suspended in and bathed by cerebrospinal fluid, which is produced by […]


Bacterial Meningitis Bacterial meningitis remains one of the most feared and dangerous infectious diseases that a physician can encounter. This form of meningitis constitutes a true infectious disease emergency. It is important that the physician quickly make the appropriate diagnosis and initiate antibiotic therapy. Minutes can make the difference between life and death in bacterial meningitis. The rapid progression of disease leaves no time to look through textbooks to decide on appropriate management. To assure the best outcome, every clinician needs a basic understanding of bacterial meningitis and its management. Epidemiology and Causes With the advent of the Haemophilus influenza В vaccine, the incidence of bacterial meningitis in children declined dramatically […]


Potential Severity An acute and severe illness associated with a high mortality. Viral Encephalitis Case 3 A 74-year-old white man with a history of chronic steroid use (10 mg prednisone daily) and stage I chronic lymphocytic leukemia presented at the emergency room with confusion and fever. Four days before admission, he complained of being increasingly tired. Two days before admission, he became increasingly lethargic, sleeping on floor. His wife had difficulty rousing him, and she noted that he was no longer interested in any activity. The morning of admission, he displayed bizarre behavior (putting underwear on top of his pajama bottoms, for example). He also became unsteady, reguiring help from his […]

Central Nervous System Abscess

Brain Abscess Potential Severity Often subacute in onset, but may be life-threatening if improperly managed. Early neurosurgical consultation is of critical importance. Case 4 A 19-year-old white man noted the gradual onset of severe left frontal headache. The headache was sharp and constant, interfered with sleep, and was not relieved by asparin. Two weeks after the onset of the headache, the teen was noted to have a grand mal seizure associated with urinary incontinence that lasted 15 minutes. On admission to hospital, he was afebrile and alert, but somewhat confused. He was oriented to person, but not to time or place. Examination of the head, ears, nose, and throat showed teeth […]

Central Nervous System Infections

Definition Central nervous system infections include a wide variety of clinical conditions and etiologies: meningitis, meningoencephalitis, encephalitis, brain and meningeal abscesses, and shunt infections. The focus of this chapter is meningitis. Pathophysiology Infections are the result of hematogenous spread from a primary infection site, seeding from a parameningeal focus, reactivation from a latent site, trauma, or congenital defects in the central nervous system. central nervous system infections may be caused by a variety of bacteria, fungi, viruses, and parasites. The most common causes of bacterial meningitis include Streptococcus pneumoniae, Neisseria meningitides, Listeria monocytogenes, and Haemophilus influenzae. The critical first step in the acquisition of acute bacterial meningitis is nasopharyngeal colonization of […]

Clinical presentation and symptoms of meningitis

The clinical signs and symptoms of meningitis are variable (See Table Mean Values of the Components of Normal and Abnormal Cerebrospinal Fluid). General Clinical presentation varies with age, and generally, the younger the patient, the more atypical and the less pronounced is the clinical picture. TABLE. Mean Values of the Components of Normal and Abnormal Cerebrospinal Fluid Type Normal Bacterial Viral Fungal Tuberculosis white blood cell (cells/mm3) <5 1000-5000 100-1000 40-400 100-500 Differential (%) >90a ≥80 polymorphonuclear neutrophils 50b,c >50b >80b,c Protein (mg/dL) <50 100-500 30-150 40-150 ≤40-150 Glucose (mg/dL) 50-66% simultaneous serum value <40 (<60%) simultaneous serum value <30-70 <30-70 <30-70 a Monocytes. b Lymphocytes. c Initial Cerebrospinal fluid, while […]