Board Review Jeopardy

Mixed Review

100

Which one of the following is true regarding NSAIDs? (check one) A. They are cardioprotective B. They should be avoided in persons with cirrhotic liver disease C. They are not safe in pregnancy D. They are not safe in lactating women

What is B. NSAIDs are prescribed commonly and many are available over the counter. It is important for clinicians to understand when they are not appropriate for clinical use. They should be avoided, if possible, in persons with hepatic cirrhosis (SOR C). While hepatotoxicity with NSAIDs is rare, they can increase the risk of bleeding in cirrhotic patients, as they further impair platelet function. In addition, NSAIDs decrease blood flow to the kidneys and can increase the risk of renal failure in patients with cirrhosis. NSAIDs differ from aspirin in terms of their cardiovascular effects. They have the potential to increase cardiovascular morbidity, worsen heart failure, increase blood pressure, and increase events such as ischemia and acute myocardial infarction. There are no known teratogenic effects of NSAIDs in humans. This drug class is considered to be safe in pregnancy in low, intermittent doses, although discontinuation of NSAID use within 6–8 weeks of term is recommended. Ibuprofen, indomethacin, and naproxen are considered safe for lactating women, according to the American Academy of Pediatrics. Ref: Risser A, Donovan D, Heintzman J, Page T: NSAID prescribing precautions. Am Fam Physician 2009;80(12):1371-1378.

200

A 72-year-old male with COPD presents to the emergency department with an acute exacerbation marked by increased sputum production and shortness of breath. His oxygen saturation is 88% on room air and he has diffuse inspiratory and expiratory wheezes bilaterally. In addition to oxygen and bronchodilators, which one of the following is most appropriate for this patient? (check one) A. No additional treatments B. Systemic corticosteroids only C. Inhaled corticosteroids only D. Systemic corticosteroids and antibiotics E. Inhaled corticosteroids and antibiotics

What is D. Acute exacerbations of COPD are very common, with most caused by superimposed infections. Supplemental oxygen, antibiotics, and bronchodilators are used for management. Systemic corticosteroids, either oral or parenteral, have been shown to significantly reduce treatment failures and improve lung function and dyspnea over the first 72 hours, although there is an increased risk of adverse drug reactions. Ref: Wood-Baker RR, Gibson PG, Hannay M, et al: Systemic corticosteroids for acute exacerbations of chronic obstructive pulmonary disease. Cochrane Database Syst Rev 2005;(4):C00075320. 2) Evensen AE: Management of COPD exacerbations. Am Fam Physician 2010;81(5):607-613.

300

You make a diagnosis of depression in a 26-year-old female. Her BMI is 32 kg/m² and she has been trying to lose weight. Which one of the following antidepressants would be LEAST likely to cause her to gain weight? (check one) A. Mirtazapine (Remeron) B. Amitriptyline C. Bupropion (Wellbutrin) D. Paroxetine (Paxil) E. Citalopram (Celexa)

What is C. Wellbutrin. Bupropion is the antidepressant least likely to cause weight gain, and may induce modest weight loss. All of the other choices are more likely to cause weight gain. Among SSRIs, paroxetine is associated with the most weight gain and fluoxetine with the least. Mirtazapine has been associated with more weight gain than the SSRIs.

400

A 75-year-old male develops a mild Clostridium difficile infection and is treated with 10 days of metronidazole (Flagyl), 500 mg orally 3 times daily. The diarrhea recurs 10 days after he completes the course of treatment. Which one of the following would be most appropriate? (check one) A. Repeat the course of metronidazole B. Repeat the course of metronidazole and add vancomycin C. Administer vancomycin intravenously D. Prescribe loperamide (Imodium), 4 mg twice daily as needed E. Prescribe a probiotic

What is A. Clostridium difficile infection is more common with aging and can be treated with either metronidazole or vancomycin daily. For mild recurrent disease, repeating the course of the original agent is appropriate (SOR B). Multiple recurrences or severe disease warrants the use of both agents. The effectiveness of probiotics such as Lactobacillus remains uncertain. Intravenous vancomycin has not been effective. Antiperistaltic drugs should be avoided. Ref: Simor AE: Diagnosis, management, and prevention of Clostridium difficile infection in long-term care facilities: A review. J Am Geriatr Soc 2010;58(8):1556-1564.

500

Which one of the following causes rhinitis medicamentosa with prolonged use in the treatment of rhinitis? (check one) A. Intranasal antihistamines B. Intranasal decongestants C. Intranasal anticholinergics D. Intranasal mast cell stabilizers E. Leukotriene antagonists

What is B. Intranasal decongestants such as phenylephrine should not be used for more than 3 days, as they cause rebound congestion on drug withdrawal. When used for several months or more, these agents can cause a form of rhinitis, rhinitis medicamentosa, that can be extremely difficult to treat. Ref: Braunwald E, Fauci AS, Kasper DL, et al (eds): Harrison’s Principles of Internal Medicine, ed 15. McGraw-Hill, 2001, pp 1920-1921. 2) Maher L: Allergic or nonallergic rhinitis? Taking the questions out of the diagnosis and treatment. American Academy of Family Physicians Video CME Program monograph, 2003, pp 12-13.

Peds

100

Two doses of varicella vaccine are recommended for: (check one) A. adults under 60 years of age who develop shingles B. all children with normal immune status C. only immunocompromised individuals D. only children between 12 months and 13 years of age

What is B. Two doses of varicella vaccine are recommended for all children unless they are immunocompromised, in which case they should not be immunized against varicella, or with other live-virus vaccines. Shingles is evidence of prior varicella infection and is a reason not to vaccinate with varicella vaccine. Ref: Zimmerman RK, Middleton DB, Burns IT, et al: Routine vaccines across the life span, 2007. J Fam Pract 2007;56(2 Suppl Vaccines):S18-S37.

200

Which one of the following is an appropriate rationale for antibiotic treatment of Bordetella pertussis infections? (check one) A. It delays progression from the catarrhal stage to the paroxysmal stage B. It reduces the severity of symptoms C. It reduces the duration of illness D. It reduces the risk of transmission to others E. It reduces the need for hospitalization

What is D. Antibiotic treatment for pertussis is effective for eradicating bacterial infection but not for reducing the duration or severity of the disease. The eradication of infection is important for disease control because it reduces infectivity. Antibiotic treatment is thought to be most effective if started early in the course of the illness, characterized as the catarrhal phase. The paroxysmal stage follows the catarrhal phase. The CDC recommends macrolides for primary treatment of pertussis. The preferred antimicrobial regimen is azithromycin for 3–5 days or clarithromycin for 7 days. These regimens are as effective as longer therapy with erythromycin and have fewer side effects. Children under 1 month of age should be treated with azithromycin. There is an association between erythromycin and hypertrophic pyloric stenosis in young infants. Trimethoprim/sulfamethoxazole can be used in patients who are unable to take macrolides or where macrolide resistance may be an issue, but should not be used in children under the age of 2 months. Fluoroquinolones have been shown to reduce pertussis in vitro but have not been shown to be clinically effective (SOR A). Ref: Manual for the Surveillance of Vaccine-Preventable Diseases, ed 4. Centers for Disease Control and Prevention, 2008, pp 10-8–10-9. 2) Mandell GL, Bennett JE, Dolin R (eds): Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases, ed 7. Churchill Livingstone, 2009, pp 2959-2960. 3) Gregory DS: Pertussis: A disease affecting all ages. Am Fam Physician 2006;74(3):420-426.

300

A 5-month-old female is brought in with a 1-day history of an axillary temperature of 100.6°F and mild irritability. Findings are normal on examination except for a runny nose and a moderately distorted, immobile, red right eardrum. There is no history of recent illness or otitis in the past. The most appropriate management would be: (check one) A. azithromycin (Zithromax) for 5 days B. amoxicillin for 10 days C. amoxicillin for 5 days D. oral decongestants E. observation and a repeat examination in 2 weeks

What is B. The treatment for otitis media is evolving. Recommendations by the American Academy of Family Physicians and the American Academy of Pediatrics advocate a 10-day course of antibiotics for children under the age of 2 years if the diagnosis is certain. If the diagnosis is not certain and the illness is not severe, there is an option of observation with follow-up. For children over the age of 2 years, the recommendation is still to treat if the diagnosis is certain, but there is an option of observation and follow-up if the illness is not severe and follow-up can be guaranteed. Amoxicillin is the first-line therapy; the recommended dosage is 80–90 mg/kg/day in two divided doses, which increases the concentration of amoxicillin in the middle ear fluid to help with resistant Pneumococcus. Azithromycin, because of a broader spectrum and potential for causing resistance, is not considered the treatment of first choice. Treatment regimens ranging from 5 to 7 days are appropriate for selected children over the age of 5 years. Oral decongestants and antihistamines are not recommended for children with acute otitis media. Ref: Neff MJ; AAP; AAFP; AAO-HNS: AAP, AAFP, AAO-HNS release guideline on diagnosis and management of otitis media with effusion. Am Fam Physician 2004;69(12):2929-2931. 2) Coleman C, Moore M: Decongestants and antihistamines for acute otitis media in children. Cochrane Database Syst Rev 2008;(3):CD001727. 3) Hoberman A, Paradise JL, Rockette HE, et al: Treatment of otitis media in children under 2 years of age. N Engl J Med 2011;364(2):105-115.

400

A 3-week-old white male presents with a history of several days of projectile vomiting after feeding, and documented weight loss despite a good appetite. There is a questionable history of a paternal uncle having surgery for a similar problem when he was an infant. Which one of the following findings is a characteristic sign of this disease? (check one) A. Hypochloremic alkalosis B. Pneumonia C. Generalized abdominal distention D. Currant jelly stool E. Direct hyperbilirubinemia

What is A. Hypertrophic pyloric stenosis is the most likely diagnosis in this case. If it is allowed to progress untreated, there may be signs of malnutrition, constipation, oliguria, and profound hypochloremic metabolic alkalosis. The latter is a characteristic sign of pyloric obstruction. As the child vomits chloride and hydrogen-rich gastric contents, hypochloremic alkalosis sets in. Pneumonia is not a common problem with pyloric stenosis, as it can be with congenital tracheoesophageal fistulae for example. After feeding, there may be a visible peristaltic wave that progresses across the abdomen. However, since the point of obstruction is proximal to the small and large intestines and affected infants lose weight, the abdomen is usually flat rather than distended, especially in the malnourished infant. Currant jelly stool is a common clinical manifestation of intussusception. Mild jaundice with elevated indirect bilirubin is seen in about 5% of infants with pyloric stenosis, but is not a characteristic sign. Ref: Bland KI, Sarr MG (ed): The Practice of General Surgery. Saunders, 2002, pp 930-933. 2) Behrman RE, Kliegman RM, Jenson HB (eds): Nelson Textbook of Pediatrics, ed 17. Saunders, 2004, pp 1219-1220, 1229-1231, 1242-1243.

500

A 5-year-old female is seen for a kindergarten physical and is noted to be below the 3rd percentile for height. A review of her chart shows that her height curve has progressively fallen further below the 3rd percentile over the past year. She was previously at the 50th percentile for height. The physical examination is otherwise normal, but your workup shows that her bone age is delayed. Of the following conditions, which one is the most likely cause of her short stature? (check one) A. Constitutional growth delay B. Growth hormone deficiency C. Genetic short stature D. Turner syndrome E. Skeletal dysplasia

What is B. This patient has delayed bone age coupled with a reduced growth velocity, which suggests an underlying systemic cause. Growth hormone deficiency is one possible cause for this. Although bone age can be delayed with constitutional growth delay, after 24 months of age growth curves are parallel to the 3rd percentile. Bone age would be normal with genetic short stature. Patients with Turner syndrome or skeletal dysplasia have dysmorphic features, and bone age would be normal. Ref: Nwosu BU, Lee MM: Evaluation of short and tall stature in children. Am Fam Physician 2008;78(5):597-604.

Dermatology

100

A 4-year-old white male is brought to your office in late August. His mother tells you that over the past few days he has developed a rash on his hands and sores in his mouth. On examination you note a vesicular exanthem on his hands, with lesions ranging from 3 to 6 mm in diameter. The oral lesions are shallow, whitish, 4- to 8-mm ulcerations distributed randomly over the hard palate, buccal mucosa, gingiva, tongue, lips, and pharynx. Except for a temperature of 37.4°C (99.3°F), the remainder of the examination is normal. The most likely diagnosis is (check one) A. herpangina B. hand, foot, and mouth disease C. aphthous stomatitis D. herpetic gingivostomatitis E. streptococcal pharyngitis

What is B. Hand, foot, and mouth disease is a mild infection occurring in young children, and is caused by coxsackievirus A16, or occasionally by other strains of coxsackie- or enterovirus. In addition to the oral lesions, vesicular lesions may occur on the feet and nonvesicular lesions may occur on the buttocks. A low-grade fever may also develop. Herpangina is also caused by coxsackieviruses, but it is a more severe illness characterized by severe sore throat and vesiculo-ulcerative lesions limited to the tonsillar pillars, soft palate, and uvula, and occasionally the posterior oropharynx. Temperatures can range to as high as 41°C (106°F). The etiology of aphthous stomatitis is multifactorial, and it may be due to a number of conditions. Systemic signs, such as fever, are generally absent. Lesions are randomly distributed. Herpetic gingivostomatitis also causes randomly distributed oral ulcers, but it is a more severe illness, regularly accompanied by a higher fever, and is extremely painful. Streptococcal pharyngitis is rarely accompanied by ulceration except in agranulocytic patients. Ref: Kliegman RM, Behrman RE, Jenson HB, et al (eds): Nelson Textbook of Pediatrics, ed 18. Saunders, 2007, pp 1352, 1361-1362, 1752-1753, 2735.

200

A 65-year-old white male comes to your office with a 0.5-cm nodule that has developed on his right forearm over the past 4 weeks. The lesion is dome shaped and has a central plug. You schedule a biopsy but he does not return to your office for 1 year. At that time the lesion appears to have healed spontaneously. The most likely diagnosis is (check one) A. benign lentigo B. lentigo maligna C. basal cell carcinoma D. squamous cell carcinoma E. keratoacanthoma

What is E. Keratoacanthoma grows rapidly and may heal within 6 months to a year. Squamous cell carcinoma may appear grossly and histologically similar to keratoacanthoma but does not heal spontaneously. The other lesions do not resemble keratoacanthoma. Ref: Habif TP, Campbell JL Jr, Chapman MS, et al: Skin Disease: Diagnosis and Treatment, ed 2. Elsevier, 2005, pp 404-407.

300

A 45-year-old white male consults you because of a painless, circular, 1-cm white spot inside his mouth, which he noticed 3 days ago. You are treating him with propranolol (Inderal) for hypertension, and you know him to be a heavy alcohol user. After a careful physical examination, your tentative diagnosis is leukoplakia of the buccal mucosa. You elect to observe the lesion for 2 weeks. On the patients return, the lesion is still present and unchanged in appearance. The best course of management at this time is to (check one) A. reassure the patient and continue to observe B. discontinue propranolol C. treat with oral nystatin D. order a fluorescent antinuclear antibody test E. perform a biopsy of the lesion

What is E. Leukoplakia is a white keratotic lesion seen on mucous membranes. Irritation from various mechanical and chemical stimuli, including alcohol, favors development of the lesion. Leukoplakia can occur in any area of the mouth and usually exhibits benign hyperkeratosis on biopsy. On long-term follow-up, 2%-6% of these lesions will have undergone malignant transformation into squamous cell carcinoma. Oral nystatin would not be appropriate treatment, as this lesion is not typical of oral candidiasis. Candidal lesions are usually multiple and spread quickly when left untreated. A fluorescent antinuclear antibody test is also not indicated, as the oral lesions of lupus erythematosus are typically irregular, erosive, and necrotic. An idiosyncratic reaction to propranolol is unlikely in this patient. Ref: Gonsalves WC, Chi AC, Neville BW: Common oral lesions: Part II. Masses and neoplasia. Am Fam Physician 2007;75(4):509-512. 2) Goldman L, Ausiello D (eds): Cecil Medicine, ed 23. Saunders, 2008, pp 1451-1452.

400

Which one of the following decreases pain from infiltration of local anesthetics? (check one) A. Cooling the anesthetic solution B. Using a 22-gauge needle rather than a 30-gauge needle C. Infiltrating quickly D. Infiltrating through surrounding intact skin E. Adding sodium bicarbonate to the mixture

What is E. The pain from infiltration of local anesthetics can be decreased by using a warm solution, using small needles, and performing the infiltration slowly.It is also helpful to add sodium bicarbonate to neutralize the anesthetic since they are shipped at an acidic pH to prolong shelf life. An exception to this tip is bupivicaine (Marciane, Sensorcaine) as it will precipitate in the presence of sodium bicarbonate. It also helps to inject the agent through the edges of the wound (assuming the wound is not contaminated) and to pretreat the wound with topical anesthetics. Ref: Singer AJ, Hollander JE, Quinn JV: Evaluation and management of traumatic lacerations. N Engl J Med 1997;337(16):1142-1148. 2) Marx JA (ed): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 6. Mosby Elsevier, 2006, pp 2930-2933.

500

A 36-year-old member of the National Guard who has just returned from Iraq consults you because of several “boils” on the back of his neck that have failed to heal over the last 6 months, despite two week-long courses of cephalexin (Keflex). You observe three 1- to 2-cm raised minimally tender lesions with central ulceration and crust formation. He denies any fever or systemic symptoms. The most likely cause of these lesions is: (check one) A. Pyogenic granuloma B. Leishmaniasis C. Atypical mycobacterial infection D. Squamous cell carcinoma E. Epidermal inclusion cysts

What is B. The most likely diagnosis is cutaneous leishmaniasis, caused by an intracellular parasite transmitted by the bite of small sandflies. Lesions develop gradually, and are often misdiagnosed as folliculitis or as infected epidermal inclusion cysts, but they fail to respond to usual skin antibiotics. Hundreds of cases have been diagnosed in troops returning from Iraq, most due to Leishmania major. Treatment is not always required, as most lesions will resolve over several months; however, scarring is frequent. U.S. military medical facilities and the CDC are coordinating treatment when indicated with sodium stibogluconate. Family physicians can play a key role in correctly identifying these lesions. Ref: Markle WH, Makhoul K: Cutaneous leishmaniasis: Recognition and treatment. Am Fam Physician 2004;69(6):1455-1460. 2) Update: Cutaneous leishmaniasis in U.S. military personnel—Southwest/Central Asia, 2002-2004. MMWR 2004;53(12):264-265.

Recent Morning Report Lectures

100

Which one of the following should be avoided in the treatment and prophylaxis of migraine during early pregnancy? (check one) A. Calcium channel blockers B. Beta-blockers C. Triptans D. NSAIDS

What is C. Triptans. Headaches, and migraines in particular, are very common in women of childbearing age. Migraine sufferers usually have improvement of symptoms in pregnancy and many have complete remission. Most medications used for prophylaxis and abortive treatment of migraines in the nonpregnant patient can also be used in pregnant patients. Most beta-blockers and calcium channel blockers are safe. Acetaminophen and narcotics can be used for acute pain. Ibuprofen can also be used but should be avoided late in pregnancy because it is associated with premature closure of the ductus arteriosus and oligohydramnios. Ergotamines should be avoided as they are uterotonic and have abortifacient properties. They have also been associated with case reports of fetal birth defects. Triptans have the potential to cause vasoconstriction of the placental and uterine vessels and should be used only if the benefit clearly outweighs the harm. Ref: Gabbe SG, Niebyl JR, Simpson JL (eds): Obstetrics: Normal and Problem Pregnancies, ed 4. Churchill Livingstone, 2002, pp 1244-1246.

200

Jennifer is a G1P0 at 30 weeks gestation with a history of depression. She is stable on 40 mg fluoxetine a day. How likely is her infant to have Neonatal Abstinence Syndrome if she continues to take fluoxetine until delivery? A. 1-5% B. 20-30% C. 40-50% D. 70-80%

What is B, up to 30%. With 3rd trimester exposure (possibly 2nd) Jitteriness, irritability, difficulty feeding Starts 24-48 hours, lasts 1-2 days Rarely requires NICU stay No difference in rates if SSRI stopped 2 weeks prior to delivery (one study) No long term developmental effect (1 study)

300

You are counseling your patient on the "RID," or relative infant dose of a medication. At what RID should caution be used when prescribing a medication? 1. 5% 2. 10% 3. 20% 4. 2% 5. What is this value?

What is 2. 10%

400

The American Cancer Society recently amended its recommendations on breast cancer screening. For low risk women, what is their new recommendation for when to begin screening? A. Age 40 B. Age 45 C. Age 50 D. Whenever you want

What is B.

500

A 5-day old newborn presents with unilateral breast hypertrophy, redness, and warmth to the touch. Parents report a fever (oral) at home but the infant is not febrile in clinic. What should you do? A. Provide reassurance and send child home with close followup B. Incise breast to try and culture any pus, then start appropriate antibiotics C. Ultrasound to rule out abscess, then start oral antibiotics D. Ultrasound to rule out abscess, then admit and start IV antibiotics

What is D.

Infectious Disease

100

A 24-year-old female presents to your clinic with a 5-day history of fever to 103°F. She has no localizing symptoms or overt physical findings. Initial testing shows an elevated WBC count with a disproportionate number of reactive lymphocytes. Which one of the following conditions is the most likely cause of these findings? (check one) A. Bacterial infection B. Connective tissue disease C. Lymphoma D. Viral infection

What is D. The conditions that result in an absolute increase in lymphocytes are divided into primary causes (usually neoplastic hyperproliferation) and secondary or reactive causes. The presence of reactive lymphocytes will often be reported on a manual differential, since they have a distinctive appearance. The most common conditions that produce a reactive lymphocytosis are viral infections. Most notable are Epstein-Barr virus, infectious mononucleosis, and cytomegalovirus. Other viral infections known to cause this finding include herpes simplex, herpes zoster, HIV, hepatitis, and adenovirus. Connective tissue disease can infrequently cause a reactive lymphocytosis, but other signs or symptoms are usually present. Bacterial infections more commonly result in an increase in neutrophils. One exception to this is Bordetella pertussis, which has been known to cause absolute lymphocyte counts of up to 70,000/μL. This infection is associated with classic symptoms that this patient does not have. Ref: Goldman L, Ausiello D (eds): Cecil Medicine, ed 23. Saunders, 2008, pp 1178, 1262-1263. 2) Mandell GL, Bennett JE, Dolin R (eds): Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases, ed 7. Churchill Livingstone, 2009, p 1999.

200

Which one of the following would most likely be found in a patient with giardiasis? (check one) A. Fecal leukocytosis B. Mucus in the stool C. Eosinophilia D. Hematochezia E. Foul-smelling flatus

What is E. The diagnosis of giardiasis is suggested by its most characteristic symptoms: foul-smelling, soft, or loose stools; foul-smelling flatus; belching; marked abdominal distention; and the virtual absence of mucus or blood in the stool. Stools are usually mushy between exacerbations, though constipation may occur. If eosinophilia occurs, it is more likely to be related to some other concomitant cause rather than to giardiasis. Ref: Fauci AS, Braunwald E, Kasper DL, et al (eds): Harrison’s Principles of Internal Medicine, ed 17. McGraw-Hill, 2008, pp 1311-1313.

300

A case of meningococcal meningitis has just been confirmed at a day-care center. The susceptibility of the microorganism is not yet known. At this point, you should do which one of the following for the day-care center contacts? (check one) A. Culture their nasopharyngeal secretions B. Administer meningococcal vaccine C. Prescribe sulfadiazine D. Prescribe chloramphenicol (Chloromycetin) E. Prescribe rifampin (Rifadin)

What is E. Rifampin. Rifampin, in the absence of major contraindications, is the drug of choice for preventing the spread of meningococcal disease when the susceptibility of the organism is not known. In this situation, meningococcal vaccines are of no value because their protective effects take a few days to develop, and because they do not protect against group B meningococci, the most prevalent strain for meningococcal disease. Sulfadiazine is the drug of choice if the meningococcus is known to be susceptible to it. Chloramphenicol and penicillin, which are effective in treating the disease, are ineffective in eliminating nasopharyngeal carriers of meningococci, possibly because they do not appear in high concentrations in saliva. Culturing contacts for meningococcal carriage in the nasopharynx has no value for identifying those at risk for meningococcal disease. Ref: Pickering LK (ed): 2003 Red Book: Report of the Committee on Infectious Diseases, ed 26. American Academy of Pediatrics, 2003, pp 123-137, 430-436.

400

A 12-year-old male is brought to your office with an animal bite. After talking with the patient, you learn that he was bitten on his left hand as he attempted to pet a stray cat a little over 24 hours ago. He says that the bite was very painful, and that it bled for a few minutes. His parents cared for the bite by rinsing it and covering it with a bandage. His chart indicates that he received a tetanus shot last year. On examination, the patient is afebrile with stable vital signs. The site is warm and tender to light palpation, with surrounding erythema measuring approximately 3 cm in diameter. Which one of the following is the most likely infectious agent in this situation? (check one) A. Candida albicans B. Capnocytophaga canimorsus C. Methicillin-resistant Staphylococcus aureus (MRSA) D. Pasteurella multocida E. Streptococcus pneumoniae

What is D. Pasteurella species are isolated from up to 50% of dog bite wounds and up to 75% of cat bite wounds, and the hand is considered a high-risk area for infection (SOR A). Although much more rare, Capnocytophaga canimorsus, a fastidious gram-negative rod, can cause bacteremia and fatal sepsis after animal bites, especially in asplenic patients or those with underlying hepatic disease. Anaerobes isolated from dog and cat bite wounds include Bacteroides, Fusobacterium, Porphyromonas, Prevotella, Propionibacterium and Peptostreptococcus. In addition to animal oral flora, human skin flora are also important pathogens, but are less commonly isolated. These can include streptococci and staphylococci, including methicillin-resistant Staphylococcus aureus (MRSA). Coverage for MRSA may be especially important if the patient has risk factors for colonization with community-acquired MRSA. Pets can also become colonized with MRSA and transmit it via bites and scratches. Cat bites that become infected with Pasteurella multocida can be complicated by cellulitis, which may form around the wound within 24 hours and is often accompanied by redness, tenderness, and warmth. The use of prophylactic antibiotics is associated with a statistically significant reduction in the rate of infection in hand bites (SOR A). If infection develops and is left untreated, the most common complications are tenosynovitis and abscess formation; however, local complications can include septic arthritis and osteomyelitis. Fever, regional adenopathy, and lymphangitis are also seen.

500

1) A 50 year old male presents in the summer to a San Diego hospital with a 3-day history of fever, chills, confusion, and weakness of the arms and legs. On examination, he had weakness of both arms and asymmetric weakness of both legs with hyporeflexia. Sensation was intact. Labs values show a normal CBC and chem18. CSF analysis showed: leukocytes count 140/uL (90% lymphocytes), protein 234 mg/dL, and normal glucose. MRI of the head and spine were normal. EMG and nerve conduction studies showed severe asymmetric peripheral neuropathy. The patient had returned one month ago from a business trip to south Florida. He received all his usual childhood immunizations and boosters while in the military, but has received no health care for the past 20 years. The most likely cause for this syndrome is: a. Poliomyelitis b. West Nile virus c. Guillain-Barre d. Epidural abscess e. Japanese Encephalitis virus

What is B. West Nile virus.