ID Flashcards
In a sexually active teen with a swollen knee, is there a infectious pathology to consider?
Gonorrhea.
Pt with GI symptoms with fever, jaundice and recent travel.
Hepatitis A
Of the top 5 bacterial infections that cause UTI, which causes nitrite to turn negative?
Staph saprophyticus
During an outbreak of the flu, what interventions would be necessary for all your unvaccinated, frail nursing home patients who have no symptoms of febrile respiratory illness?”
“Antiviral prophylaxis with oseltamivir Influenza immunization” “Persons at high risk for complications of influenza can still be vaccinated after an outbreak of influenza has begun in the community, but development of antibodies in adults can take up to 2 weeks. Thus, chemoprophylaxis should be considered for persons at high risk during the time from vaccination until immunity has developed. Oseltamivir alone might be appropriate for individuals who have a contraindication to vaccination and wish to protect themselves from influenza” Amantidine resistance has developed for influenza A and it doesn’t work on B.
What are the recommendations for antiviral drugs to the treat flu infection in outpatients? And inpatients?
“Persons at high risk for complications of influenza can still be vaccinated after an outbreak of influenza has begun in the community, but development of antibodies in adults can take up to 2 weeks. Thus, chemoprophylaxis should be considered for persons at high risk during the time from vaccination until immunity has developed. “A” alone might be appropriate for individuals who have a contraindication to vaccination and wish to protect themselves from influenza”
Who should receive the pneumococcal vaccination?
“Pneumococcal vaccine: Indications for pneumococcal vaccination include patients with chronic illness at high risk for invasive pneumococcal disease (e.g., diabetes, chronic pulmonary disease, and cardiovascular disease), institutionalization, age 65 or older, immunocompromised state, and tobacco use. Note that the tobacco use indication is relatively recent and applies to all patients age 19-64years old. Patients with an immunosuppressive disorder (e.g., HIV, asplenia, renal failure, and organ transplant) should have a one-time revaccination at least 5 years after initial vaccination”
What is the most common cause of diarrhea in hospitalized patients?
“C. difficile is the most common bacterial cause of infectious diarrhea in hospitalized patients in the United States (Campylobacter jejuni is the most common bacterial cause overall). The antibiotics most commonly associated with C. difficile diarrhea are clindamycin, fluoroquinolones, and broad-spectrum cephalosporins. The assay for C. difficile cytotoxin is only about 75% sensitivity (enzyme immunoassay). There are several subtypes of toxin, some of which are not detected by this assay. Although symptomatic therapy is important, antiperistaltic agents should be avoided in patients with C. difficile. Although other causes of diarrhea are possible, the most cost-effective approach in this patient would be stool assay for C. difficile repeated on two to three specimens (to improve sensitivity) prior to any other more invasive procedure”
What is the treatment of c. Dificile colitis?
“Treatment includes supportive care, discontinuation of the offending antimicrobial agent, and initiation of oral metronidazole 250 mg four times daily or 500 mg three times for 10 days. Metronidazole is preferred over vancomycin because of the nearly identical efficacy and relapse/reinfection rates, lower cost, and lower theoretical risk of promotion of vancomycinresistant Enterococcus faecalis (VRE). Consider vancomycin first line if the patient has severe disease (white blood cell (WBC) >15,000, creatinine >1.5x baseline). Dificid (fidaxomicin) has recently been approved for C. difficile colitis. However, the NNT = 10 to prevent one recurrence. It is certainly NOT first (or even second) line.
Risk”
Name for risk factors for c. diff colitis in nursing home patients?
“Risk factors for acquisition of C. difficile infection in nursing home patients are similar to that of hospitalized patients and include hospitalization, advanced age, GI surgery/procedures and antibiotic exposure and, importantly PPI use.”
What are the treatments for C. diff colitis?
PO vancomycin for metronidazole tid. Rehearse with in one week is common and happens in about 20% of patients. Repeating the vancomycin metronidazole treatment for 10 more days is a common treatment for recurrence. “C. difficile diarrhea and colitis can be caused by any antibiotic, including metronidazole and vancomycin. The probability of diarrhea seems highest with clindamycin. Fluoroquinolones are increasingly associated with C. difficile infection, including a highly toxigenic strain. Simply stopping the antibiotic can lead to resolution in 25% of the cases.” “IV vancomycin is ineffective treatment of C. difficile since vancomycin does not enter into the GI tract from the vascular space.”
For a patient with new onset headache and meningeal signs, when should you perform a lumbar puncture?
“Once you suspect bacterial meningitis, rapid diagnostic evaluation and emergent treatment are imperative, including lumbar puncture and blood cultures. If lumbar puncture is going to be delayed, then appropriate empiric antimicrobial and adjunctive therapy should be given without delay. Head CT is necessary only in those who are immunocompromised (HIV/AIDS, those receiving immunosuppressive drugs, transplant recipients), have a history of CNS disease (brain tumor and stroke), develop new onset seizures, display papilledema on exam, or who have an abnormal/focal neurologic deficit or abnormal level of consciousness. Antibiotics for a 40-year-old male should cover Neisseria meningitidis and S. pneumoniae, and would include vancomycin and ceftriaxone. Never wait for a CBC to determine if an adult needs an LP. The decision to do an LP is a clinical one.”
What is the standard of care for giving antibiotics for suspected meningitis?
“The standard of care for suspected meningitis is to administer antibiotics within 30 minutes of the patient presenting to the ED. Draw the blood cultures and give the antibiotics. You won’t change the CSF culture results if you give a single dose of antibiotics prior to CT scan. However, it is considered prudent to do the LP within 2 hours of administering IV antibiotics”
Examination of the cerebral spinal fluid of a patient with suspected meningitis reveals gram-positive cocci in pairs. What is the most likely cause of agent?
“Gram stain examination of CSF may permit rapid identification of the causative organism in bacterial meningitis with a sensitivity of 60–90%. Prior antibiotic therapy (e.g., a partially treated meningitis… not a single dose of antibiotics in the ED) may reduce the sensitivity by 20%. The likelihood of a positive Gram stain is highest in cases of S. pneumoniae (a gram-positive diplococcus). Only about one-third of L. monocytogenes meningitis cases demonstrate a positive Gram stain. Answer “D” requires special mention. N. meningitidis is a diplococcus but is gram negative”
What is the most common cause of meningitis in the college students? In those over 50? In neonates?
“Although S. pneumococcus is the most common cause of bacterial meningitis in the adult population in the United States, N. meningitidis remains the leading cause in adolescents despite vaccination and is particularly prevalent in the setting of dormitory living (e.g., college or military). In addition, the presence of petechial (or purpuric) rash in the lower extremities and pressure points is typical of N. meningitidis. The advent of vaccination has made H. influenzae a less common cause. L. monocytogenes is more prevalent in those over age 50, infants, and immunocompromised. E. coli is a common cause for meningitis in neonates and infants but is very uncommon in adolescents and adults”
An asymptomatic patient is positive for a PPD skin test with 15 mm of induration. They were previously negative. What is the course of treatment?
“A 3-month course of INH plus rifapentine (note, not rifampin) once weekly has been shown to be superior to a 9-month course of daily INH. As of the writing of this book, the 3-month regimen is not yet the current standard of care.” “Pyridoxine should also be given to prevent peripheral neuropathy”
What is the treatment for the patient was active TB?
“If active disease is diagnosed, appropriate therapy should be initiated with a 4-drug regimen for 6–8 weeks followed by a simpler regimen for 4–7 months once sensitivities are known (average 6 months total). A number of regimens are available, and all include isoniazid and rifampin. INH alone is never appropriate for active TB. First-line drugs used for active TB include isoniazid, rifampin, pyrazinamide, and ethambutol. Ethambutol may be dropped if the organism is sensitive to INH, RIF, and PYR. Second-line drugs include levofloxacin, streptomycin, and others”
According to the American Heart Association guidelines what is the prophylaxis for mitral valve prolapse with regurgitation?
MVP with regurgitation has been downgraded and there is no prophylaxis.
According to the American Heart Association what conditions are considered high risk for the development of endocarditis?
“The guidelines recommend antibiotic prophylaxis for conditions considered to be high risk for adverse outcomes of infective endocarditis. High-risk conditions include prosthetic valves (bioprosthetic homograft and allograft valves and mechanical valves), previous infective endocarditis, and complex cyanotic congenital heart disease”
What are the classical findings of subacute bacterial endocarditis?
“Classical physical exam findings of SBE include intermittent fever; petechiae; conjunctival hemorrhage; splinter hemorrhages under the nails; erythematous painful nodules on the fingers, palms, and soles (Osler nodes); fundic hemorrhages (Roth spots); painless erythematous macules on the palms and soles (Janeway lesions); and new diastolic murmur”
What is the drug of choice for MSSA endocarditis?
“Nafcillin is the drug of choice for the treatment of methicillin-sensitive S. aureus endocarditis. Vancomycin should be reserved for patients with penicillin allergy or patients with methicillin-resistant S. aureus (MRSA). Neither ceftriaxone nor levofloxacin would be considered appropriate therapy for staphylococcal endocarditis.”
How do you manage a patient with progressive heart failure and worsening valvular function?
“Progressive heart failure and worsening valvular function are indications for surgery. However, it is generally preferable to complete the course of antibiotics first if the patient’s heart failure can be effectively medically managed”
“Other indications for surgery in cases of endocarditis include multiple embolic events, infections that are difficult or impossible to treat adequately with medications (e.g., fungal infections), cardiac conduction abnormalities due to infection, persistent bacteremia, partially dehisced prosthetic valve, and perivalvular infection (e.g., cardiac abscess and fistula).”
What are the most likely organisms to cause bacterial endocarditis?
“S. viridans is the most likely organism to cause endocarditis. Gram-negative organisms, such as E. coli and P. mirabilis, are infrequent causes of infective endocarditis. Other organisms that cause endocarditis include the HACEK organisms (Haemophilus species, Actinobacillus actinomyces comitantes, “Cardiobacterium hominis, Eikenella species, and Kingella kingae).”
Name to drugs there contraindicated when taken linezolid.
“Linezolid can cause serotonin syndrome when combined with SSRIs, lithium, MAOIs, and other serotonergic drugs”
