B3cre-2.docx

Student Number: 14284248

Clinical Reasoning Exam 2 Block 3, 2017-2018 (50 points) Monday, February 26, 2018 19 yo male, Jeremy Johnson, lying in bed moaning and groaning and was found shaking and turning blue most likely from a seizure with involuntary motor activity of approximately 1 min. Mr. Johnson has been sick for 2 days with a fever and a headache and had missed class. He has weakness and photophobia. Did not respond to verbal stimuli but did respond to pain. He has a BMI of 24.1 and a 101.3 fever. Fresh blood was present in his mouth (most likely from biting his tongue) and he had been incontinent of urine. 2 days ago he consumed a large amount of beer and has been irritable and consumed little food. He has taken aspirin and acetaminophen for the headache. He has a history of asthma. Drinks beer on weekends and smokes marijuana occasionally. Roommate had been treated for strep pharyngitis and dorm had mono. A few weeks ago, Mr. Johnson had traveled to Chicago. Could not identify the governor of the state and was confused. Small nonbleeding laceration found on tip of the tongue. Reflexes were 3+ but symmetrical. BUN was slightly high, glucose was high, serum prolactin was high, LDH was high, and CK was high, Ketones were present in urine. Normal chest X-ray and head CT, CSF was abnormal. 1. What are your hypotheses (maximum 5)? Provide support for each hypothesis. Clearly state which is your top hypothesis. (20 points; page limit: 3 pages) Score:

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Answer: Viral Meningitis due to EBV. EBV is a widely disseminated herpesvirus that is spread by intimate contact between asymptomatic EBV shedders. EBV is the primary agent of infectious mononucleosis and can progress to meningitis and encephalitis in some cases as the acute infectious mononucleosis progresses.  Pertinent Positives: o Fever of 101.3, headache, and photophobia are present and a positive nuchal rigidity were present which all indicative of meningitis. o The fact that the dormitory had mono and the fact that mono is highly contagious means Mr. Johnson could have obtained it via kissing, being sneezed on, or drinking a drink from an infected individual. The patient’s common beer consumption could have been one method of obtaining EBV as he may have unknowingly shared beers with individuals infected with EBV. o Viral meningitis can progress to seizures in certain cases and can account for Mr. Johnson’s likely seizure and would have led to him biting his lip accounting for the blood in his mouth upon exam. o The elevated prolactin level is most likely due to his seizure, which could have been caused by his viral meningitis. o The abnormal CSF of a clear CSF, with a high WBC count of 90% mononuclear cells WITH blood indicates some sort of encephalitis, which would not be seen on Block 3, Clinical Reasoning Exam 2, 2017-2018

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Student Number: 14284248

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CT scan. The most likely encephalitis in this patient’s age range and location (dormitory) and the fact that mono was going around points to a EBV encephalitis which would produce blood in the CSF. o The patients high WBC count could potentially indicate an acute infectious mononucleosis. Pertinent Negatives: o Epstein Barr Virus usually has an incubation period of 30-50 days in adolescents and include symptoms of sore throat, headache, fever, myalgias, nausea, and abdominal pain. We currently do not know if the patient has undergone these symptoms as the roommate does not know. o No spleen enlargement on abdominal exam o Normal AST ALT levels would be less likely in patients infected with EBV but there is still a chance the patient may not have elevated levels as around 20% do not have elevated levels.

Tick borne encephalitis as the patient has recently traveled to Colorado. In Colorado the patient might have picked up a Colorado tick resulting in a Colorado tick fever.  Pertinent Positives: o Mr. Johnson has recently traveled to Colorado approximately a “few weeks ago” and is NOW presenting with symptoms. The incubation period before symptoms present for Colorado tick fever according to the CDC is 1-14 days. This would fit with the time frame of when Mr. Johnson traveled to Colorado o Patients can develop tick encephalitis and lead to meningitis. Arboviruses or diseases carried by arthropods can result in meningitis and thus the photophobia, high fever, and nuchal rigidity o Tick borne encephalitis is a viral encephalitis and would account for the clear CSF and RBC’s noticed on lumbar puncture. o The encephalitis could have resulted in cognitive disturbances and behavioral changes as witnessed by Mr. Johnson cursing the physician and pushing him away in addition to the seizure and consequently the elevated serum prolactin level that was experienced.  Pertinent Negatives: o Patients with Colorado tick fever usually have vomiting, abdominal pain, and sometimes a skin rash. o No skin rash was identified on skin exam but this does not rule out the possibility of a tick. In addition the roommate was unable to identify if Mr. Johnson has had any of the aforementioned symptoms and thus tick related diseases can still not be ruled out. HSV 1 encephalitis is the most common cause of sporadic fatal encephalitis. The disease is characterized by rapid onset of fever, headache, seizures, focal neurologic signs, and impaired consciousness.  Pertinent Positives: o The patient presents with fever of 101.3 and a headache for which he has been taking acetaminophen and aspirin. In addition he is exhibiting psychiatric symptoms of cursing and pushing away the physician. Block 3, Clinical Reasoning Exam 2, 2017-2018

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Student Number: 14284248

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o Mr. Johnson also exhibited a seizure which would be indicative of encephalitis and could have lead to his elevated serum prolactin level. o Although there is currently no rash there is not a relationship between peripheral lesions and HSV1 encephalitis so this finding does not rule down HSV-1. Abnormalities may not be seen on CT scanning initially but would be seen on an MRI. Pertinent Negatives: o The patient is currently claiming to not be in a sexual relationship but could have been exposed at any time. In addition, sexual relationships are usually not the cause of HSV-1, so this fact does not rule out the idea of HSV1 encephalitis.

2. Interpret the CSF. (5 points; page limit: 1 page) Score:

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Answer: The patient has a high opening pressure, a clear CSF, a very high WBC count with 90% being mononuclear, RBC’s present, high protein, and a high glucose concentration with a negative gram stain. A clear CSF points to a viral meningitis w/potential encephalitis and the high protein also is indicative of a viral meningitis. The high glucose found in the CSF can most likely be ignored because the patient’s serum glucose was also high which can complicate the results of a CSF due to glucose diffusing down the gradient from blood to CSF. The RBC’s usually indicate either a SAH, an IC hemorrhage, a cerebral infarct, or a traumatic spinal tap. Because the Head CT shows no evidence of a SAH or subdural bleeding, those options can be removed. A traumatic spinal tap would not be shown with a normal opening pressure so most likely the RBC’s are due to some destruction of brain tissue from viral encephalitis, most likely due to a herpes family virus condition like EBV. This would most likely be seen on an MRI.

3. Would you obtain an MRI of the brain in this patient? Explain. (10 points, page limit: 1 page) Score:

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Answer: I would be strongly inclined to obtain an MRI in this patient. Because of the bloody CSF that was due to a SAH or a traumatic tap the next likely culprit is encephalitis. CT scan’s don’t quite show encephalitis that well, but an MRI with contrast is the criterion standard in visualizing intracranial pathology associated with viral encephalitis. Obtaining a MRI would also help to distinguish between whether the cause is because of EBV or HSV-1. HSV-1 typically affects basal frontal and temporal lobes with a typical visual image of diffusely Block 3, Clinical Reasoning Exam 2, 2017-2018

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Student Number: 14284248 enhancing bilateral lesions. Although not indicated quite in this patient’s case a more thorough patient history should be performed once the patient is stabilized. In addition an MRI w/contrast should be obtained because a CT with contrast was NOT obtained. While the CT scan was performed to indicate if their was a mass so that the physician could proceed with the lumbar puncture without worry of herniating the brain, a contrast CT would have showed if the meninges were inflamed. If there was no blood in the CSF then obtaining a CT scan w/contrast might have been enough, but because there is blood, there is some sort of pathology that can be better visualized with a MRI. 4. What are the next steps in management of this patient? (15 points; page limit: 2 pages) Score:

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For the diagnosis of viral meningitis due to EBV, an MRI should be obtained first to see if there are any areas of the brain that are undergoing encephalitis or any pathology. Next treatment should be begun. Because viral meningitis would not respond to antibiotics, treatment for viral meningitis is mostly supportive. Rest, hydration, antipyretics, pain or antiinflammatory medications may be given. A consult to a neurologist should be made to identify if there are any precipitating factors for the seizures that may have been missed and to place him on a prophylactic drug regimen to prevent further seizures from forming (most likely phenytoin/valproic acid) For the diagnosis of tick borne encephalitis, obtain a tick borne disease antibody panel and molecular detection, and PCR of common tick diseases. Once the causative agent for the tick borne encephalitis is obtained the physician can proceed with treatment. Unfortunately for TBE, there is no specific drug therapy for TBE. The patient should receive supportive care. Anti-inflammatory drugs, such as corticosteroids, may be considered under specific circumstances for symptomatic relief. Intubation and ventilator support may be necessary if the patient is unable to breathe. For the diagnosis of HSV-1 encephalitis the detection of HSV DNA in the CSF by PCR should be performed as it has a very high sensitivity and specificity. In addition, although a CSF was obtained only a gram stain was performed which was negative for organisms but a gram stain would not show a virus. A repeat CSF should be performed to rule out the possibility of HSV-1. Prognosis is usually bleak but treatment should be administered quickly with IV acyclovir. Persistent neurological deficits may remain and psych services should be consulted to talk about potential future complications.

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Student Number: 14284248 References (not included in the page limit) should include sufficient detail to allow the grader to identify the source. Include title and author(s) of the article or chapter, title of the journal or textbook, and year of publication.           

Johnson BW, Kosoy O, Martin DA, et al. West Nile virus infection and serologic response among persons previously vaccinated against yellow fever and Japanese encephalitis viruses. Vector Borne Zoonotic Dis 2005; 5:137. Arrigo NC, Adams AP, Weaver SC. Evolutionary patterns of eastern equine encephalitis virus in North versus South America suggest ecological differences and taxonomic revision. J Virol 2010; 84:1014. Centers for Disease Control and Prevention (CDC). Eastern Equitne Encephalitis; epidemiology and geographic distribution. https://www.cdc.gov/easternequineencephalitis/tech/epi.html (Accessed on August 14, 2017). Centers for Disease Control and Prevention (CDC). Eastern equine encephalitis--New Hampshire and Massachusetts, August-September 2005. MMWR Morb Mortal Wkly Rep 2006; 55:697. Parasuraman TV, Frenia K, Romero J. Enteroviral meningitis. Cost of illness and considerations for the economic evaluation of potential therapies. Pharmacoeconomics 2001; 19:3. Connolly KJ, Hammer SM. The acute aseptic meningitis syndrome. Infect Dis Clin North Am 1990; 4:599. Kupila L, Vuorinen T, Vainionpää R, et al. Etiology of aseptic meningitis and encephalitis in an adult population. Neurology 2006; 66:75. MEYER HM Jr, JOHNSON RT, CRAWFORD IP, et al. Central nervous system syndromes of "vital" etiology. A study of 713 cases. Am J Med 1960; 29:334. Rotbart H. Viral meningitis and the aseptic meningitis syndrome. In: Infections of the Central Nervous System, Scheld W, Whitley RJ, Durack DT (Eds), Raven, New York 1991. p.19 Hjalmarsson A, Blomqvist P, Sköldenberg B. Herpes simplex encephalitis in Sweden, 19902001: incidence, morbidity, and mortality. Clin Infect Dis 2007; 45:875. Corey L, Whitley RJ, Stone EF, Mohan K. Difference between herpes simplex virus type 1 and type 2 neonatal encephalitis in neurological outcome. Lancet 1988; 1:1.

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