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1. A 45-year-old patient with alcoholic cirrhosis presents with confusion and increasing abdominal pain and pressure over the past week. A paracentesis is performed, revealing 520 WBCs with 89% polymorphonuclear leukocytes and 11% lymphocytes. The protein level is high, but the glucose level is normal. What is the best course of treatment?
A. Administer a third-generation cephalosporin
B. Administer ampicillin and an aminoglycoside
C. Start probiotic therapy and a fluoroquinolone
D. Withhold antibiotics pending Gram stain and culture
The correct answer is A, Administer a third-generation cephalosporin.
Why is this the correct answer?
Spontaneous bacterial peritonitis (SBP) is associated with high mortality rates and should be considered in any patient with ascites who presents with fever, chills, malaise, abdominal pain, confusion, hypotension, or general clinical decline. The current treatment of choice for SBP is a third-generation cephalosporin (eg, cefotaxime 2 g every 8 hours). The physical examination findings in patients with SBP are often vague. The definitive diagnosis is made by performing diagnostic paracentesis with collection of ascitic fluid for total leukocyte count, polymorphonuclear leukocyte (PMN) count, lymphocyte count, and fluid culture. Positive fluid culture confirms the diagnosis, but antibiotics should be started before results return.
The diagnosis is not always clear — none of these characteristic features are consistently present in all patients and some patients are asymptomatic. The definition of SBP includes a PMN count greater than 250 cells/mm3; it can be calculated by multiplying the fluid cell count by the percentage of PMNs reported. A total leukocyte count greater than 500 to 1,000 cells/mm3 strongly correlates with positive fluid cultures. Symptomatic patients with a PMN count less than 250 cells/mm3 should still be admitted for treatment with antibiotics, with the regimen determined based on culture results.
Why are the other choices wrong?
Combination antibiotic therapy with ampicillin and an aminoglycoside is an alternative to treatment with a third-generation cephalosporin. However, ampicillin has an increased side effect profile with increased risk of nephrotoxicity, so it is not the best course of treatment.
Probiotic therapies have not been shown to increase antibiotic effects or reduce mortality rates, and they have no role in the treatment of SBP. Fluoroquinolone or trimethoprim-sulfamethoxazole prophylaxis for high-risk patients (ie, those who have had SBP before) might prevent future episodes and associated hepatorenal syndrome. However, these lead to drug-resistant peritonitis and are not primary therapies.
Antibiotics should be given based on clinical suspicion and started before culture or Gram stain results are available. Gram stain is not very sensitive for visualizing bacteria in early SBP, and culture results can be falsely negative; they do not alter management decisions in the inpatient setting.
REFERENCES
Haines EJ, Thompson H. Liver and biliary tract disorders. In: Walls RM, Hockberger RS, Gausche-Hill M, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. Vol 1. 10th ed. Elsevier; 2023:1058-1083.
O'Mara SR, Wiesner L. Hepatic disorders. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:516-523.
Medscape article on spontaneous bacterial peritonitis
https://emedicine.medscape.com/article/789105-overview
Medscape article on ascites
https://emedicine.medscape.com/article/170907-overview
UpToDate article on SBP, available in full with a subscription
2. Which medication is contraindicated in the treatment of thyroid storm?
A. Cholestyramine
B. Esmolol
C. Iodine
D. Salicylic acid
The correct answer is D, Salicylic acid.
Why is this the correct answer?
Clinical manifestations of thyroid storm include tachycardia and fever, but ophthalmopathy, goiter, neurological dysfunction, hand tremors, jaundice, and GI symptoms may also be present. Fever is quite common, and temperatures of 40°C to 41.1°C (104°F to 106°F) are not unusual. It is safe to give acetaminophen, but salicylic acid should be avoided in patients with thyroid storm because it may interfere with protein binding of T3 and T4 in the serum, thus increasing concentrations of free T3 and T4.
Treatment of thyroid storm requires a multipronged approach. Beta-blockers should be given immediately following the recognition of thyroid storm unless there are contraindications, such as severe asthma. Thionamides, which block synthesis of thyroid hormones, should also be given immediately. Propylthiouracil is often preferred over methimazole in the acute setting because it blocks conversion of T4 to T3. Iodine, usually in the form of Lugol solution or potassium iodide, should be administered 1 hour after the first dose of thionamide. Glucocorticoids (typically hydrocortisone) inhibit T4-to-T3 conversion and may treat underlying autoimmune disorders (eg, Graves disease), if present. Bile acid sequestrants may also reduce thyroid hormone levels. Antibiotics should be strongly considered since infection is a common precipitating factor in thyroid storm. Lithium also blocks the release of thyroid hormone, but it has significant renal and neurologic toxicity.
Why are the other choices wrong?
Bile acid sequestrants, such as cholestyramine, may be given as an adjunctive therapy in the treatment of thyroid storm. Bile acid sequestrants reduce reabsorption of thyroid hormone from the enterohepatic circulation and may be particularly useful in patients who cannot tolerate thionamides due to allergy or hepatotoxicity.
Either esmolol or propranolol may be given to patients in thyroid storm unless the patient has a contraindication to beta blockade. In patients with asthma, a more cardioselective beta-blocker (eg, metoprolol or atenolol) may be cautiously considered.
Iodine should be given to treat thyroid storm 1 hour after the first dose of thionamide. This delay prevents the iodine from being used for the manufacture of additional thyroid hormone. Iodine is usually given in the form of Lugol solution or potassium iodide.
REFERENCES
Idrose AM. Hyperthyroidism and thyroid storm. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1450-1457.
UpToDate article on thyroid storm, available in full with a subscription
https://www.uptodate.com/contents/thyroid-storm
Carroll R, Matfin G. Endocrine and metabolic emergencies: thyroid storm. Ther Adv Endocrinol Metab. 2010 Jun;1(3):139-145.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3475282/
3. A 22-year-old woman presents with a red and painful arm several days after she scraped it on a fence. She says the redness is "getting bigger by the minute" and rates the pain as severe. Her vital signs include BP 90/60, P 110, and T 38.4°C (101.1°F). Her forearm is warm and erythematous, and there is crepitus. What is the best approach to diagnosing the most likely condition in this case?
A. CT
B. MRI
C. Surgical exploration
D. Wound cultures
The correct answer is C, Surgical exploration.
Why is this the correct answer?
Given the physical findings, the patient's complaints of pain, and the rapid progression, the most likely diagnosis is necrotizing fasciitis. The gold standard for diagnosing necrotizing fasciitis is also its treatment: surgical exploration. Necrotizing fasciitis causes soft-tissue destruction and has a high mortality rate. This diagnosis is frequently missed because it can appear benign on examination early in its course; the early symptoms can resemble cellulitis, but as the disease progresses, examination may reveal crepitus or brawny edema.
Patients with necrotizing fasciitis typically have pain out of proportion to examination findings, which is one of the most important diagnostic features. As the disease progresses, the affected area can become insensate and obscure the pain. Later in the course, drainage or bullae can also manifest. Necrotizing fasciitis can progress to systemic manifestations, such as fevers and tachycardia; patients develop severe sepsis late in necrotizing infections. Persons with immunocompromising diseases and those who take immunosuppressant medications are at increased risk for these infections. Antibiotics are an extremely important part of treatment, but they are rarely curative. If clinical suspicion is high, early surgical consultation is of highest importance and should be pursued before obtaining any radiographic images.
Why are the other choices wrong?
CT has a higher sensitivity (~80%) for necrotizing fasciitis than plain x-rays. It can show edema and gas formation; however, if these findings are not there, necrotizing fasciitis cannot be ruled out. Direct visualization is ultimately the best method of diagnosing this potentially fatal condition, so early surgical consultation should precede imaging if clinical suspicion is high.
MRI has the highest radiographic sensitivity for necrotizing fasciitis, as high as 90% to 100%, but its negative predictive value has not been well determined. Furthermore, the time it takes to obtain an MRI delays the ultimate treatment of surgical intervention in this time-sensitive condition.
Wound cultures are not the best method to diagnose necrotizing fasciitis, and antibiotics alone are rarely curative. Necrotizing fasciitis is commonly polymicrobial. Antibiotic therapy should be initiated immediately and be broad spectrum, with coverage for gram-positive cocci, gram-negative rods, and anaerobes. Coverage for Group A Streptococcus and Vibrio vulnificus should also be considered. Surgery is both diagnostic and therapeutic, and it is the best approach to diagnosing this emergent condition.
REFERENCES
Pulia M, May LS. Skin and soft tissue infections. In: Walls RM, Hockberger RS, Gausche-Hill M, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. Vol 2. 10th ed. Elsevier; 2023:1728-1739.
Kelly EW. Soft tissue infections. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:1005-1013.
UpToDate article on necrotizing soft-tissue infections, available in full with a subscription
https://www.uptodate.com/contents/necrotizing-soft-tissue-infections
4. A 49-year-old man is brought in by his family who say that they cannot take care of him anymore because of his impulsive wandering and disinhibited behavior. The family was told 6 months ago that the patient has dementia, and he has declined progressively since then. What type of dementia does the patient most likely have?
A. Alzheimer’s disease
B. Frontotemporal neurocognitive disorder
C. Neurocognitive disorder with Lewy bodies
D. Prion disease
The correct answer is B, Frontotemporal neurocognitive disorder.
Why is this the correct answer?
Based on this patient's relatively young age and behavioral changes, the most likely diagnosis of the choices listed is frontotemporal neurocognitive disorder. Major neurocognitive disorders, also referred to as dementia, are subtyped according to their presumed underlying etiologies. Each is associated with varying degrees and types of cognitive impairment and interference with everyday activities. Frontotemporal neurocognitive disorder is a common cause of dementia in patients younger than 65 years and is frequently associated with disruptive behavioral changes that are more prominent than the other cognitive impairments. These might include hyperorality, wandering, and generally disinhibited behavior. Median survival after diagnosis of frontotemporal neurocognitive disorder is 3 to 4 years, with a more rapid decline and shorter survival than with Alzheimer disease.
Why are the other choices wrong?
The biggest risk factor for developing Alzheimer disease is age. The age of onset is usually in the eighth or ninth decade of life, although it can be seen earlier in patients with a strong genetic predisposition. Patients typically present with memory loss and decline in executive functioning. Aphasia (language disturbance), apraxia (impaired motor ability), and agnosia (difficulty recognizing objects) are also sometimes seen.
In addition to developing problems with executive function and attention, patients with neurocognitive disorder with Lewy bodies also present with complex visual hallucinations and REM sleep behavior disorder. Their symptoms may wax and wane and resemble delirium, but no underlying cause is identified. Most patients develop symptoms in their mid-70s.
The neurocognitive disorders caused by prion disease typically manifest as neurocognitive deficits and significant motor abnormalities, such as ataxia, myoclonus, dystonia, or chorea. This category of neurocognitive disorders includes spongiform encephalopathies such as kuru, bovine spongiform encephalopathy (“mad cow” disease), and Creutzfeldt-Jakob disease. These diseases progress rapidly and can present at any age.
REFERENCES
Neurocognitive disorders. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. American Psychiatric Association; 2013.
Scher LM, Hsu DC. The patient with delirium and dementia in the emergency department. In: Zun L, Chepenik LG, Mallory MNS, eds. Behavioral Emergencies for the Emergency Physician. Cambridge University Press; 2013:117-124.
UpToDate article on frontotemporal dementia, available in full with a subscription
https://www.uptodate.com/contents/frontotemporal-dementia-clinical-features-and-diagnosis
5. Which technique should be attempted first to remove a nasal foreign body without the use of restraints in a young pediatric patient?
A. Back blows
B. Bag-valve-mask positive pressure
C. Forceps
D. Parent’s kiss
The correct answer is D, Parent’s kiss.
Why is this the correct answer?
Multiple techniques have been described to remove nasal foreign bodies in pediatric patients. The use of a “parent’s kiss” or “mother’s kiss” has been described as very successful (approximately 80% effective), and parents preferred the technique to others using instruments or patient restraint. The technique is performed by telling the patient that the parent is going “to give you a big kiss.” The parent then occludes the nonaffected nostril and blows a short, quick breath into the patient’s mouth. The technique can be repeated until successful removal of the foreign body. Mucosal application of topical lidocaine and a vasoconstrictor such as phenylephrine before attempting any other nasal foreign body removal technique reduces patient discomfort and helps make the attempt successful. If this and other techniques fail, otolaryngology consultation is warranted.
Why are the other choices wrong?
Back blows are used in infants and other young pediatric patients to remove suspected obstructive airway foreign bodies. This technique is not recommended for nasal foreign body removal.
The bag-valve-mask (BVM) positive-pressure technique involves placing the BVM device sideways on the patient’s face, covering just the mouth. The physician occludes the nonaffected nostril and delivers positive pressure through the BVM. Although this technique is effective, it often requires restraint.
The forceps technique is also effective for nasal foreign body removal. However, it requires physical restraint or procedural sedation to be successful.
REFERENCES
Botma M, Bader R, Kubba H. 'A parent's kiss': evaluating an unusual method for removing nasal foreign bodies in children. J Laryngol Otol. 2000 Aug;114(08):598-600.
Purohit N, Ray S, Wilson T, Chawla OP. The 'parent's kiss': an effective way to remove paediatric nasal foreign bodies. Ann R Coll Surg Engl. 2008 Jul;90(5):420-422.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2645753/
Riviello RJ. Otolaryngologic procedures. In: Roberts JR, Custalow CB, Thomsen TW, et al, eds. Roberts and Hedges’ Clinical Procedures in Emergency Medicine and Acute Care. 7th ed. Elsevier; 2019:1338-1383.
Cohen JS, Agrawal D. Nose and sinus disorders in infants and children. In: Tintinalli JE, Ma OJ, Yealy DM, et al, eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill Education; 2020:772-775.
ALiEM article on the balloon extraction technique
https://www.aliem.com/trick-of-the-trade-improvised-foreign-body-removal-device/
UpToDate article on intranasal foreign bodies, available in full with a subscription
https://www.uptodate.com/contents/diagnosis-and-management-of-intranasal-foreign-bodies