AAFP Board Review - ID
A 4-week-old white male is brought to your office with a 2-week history of increasing
dyspnea, cough, and poor feeding. The child appears nontoxic and is afebrile. On
examination you note conjunctivitis, and a chest examination reveals tachypnea and
crackles. A chest film shows hyperinflation and diffuse interstitial infiltrates and a WBC
count reveals eosinophilia.
What is the most likely etiologic agent? (check one)
A. Staphylococcus species
B. Chlamydia trachomatis
C. Respiratory syncytial virus
D. Parainfluenza virus - Answers -B. Chlamydial pneumonia
- usu in infants 3 - 16 wks; pt sick for weeks
- infant nontoxic & afebrile, tachypneic w/ prominent cough
- physical examination: diffuse crackles with few wheezes, and conjunctivitis (50% of
cases).
- CXR: hyperinflation and diffuse interstitial or patchy infiltrates.
Not Staphylococcal pneumonia
- fever, initial expiratory wheeze like bronchiolitis
- PE: abdominal distress, tachypnea, dyspnea, and localized or diffuse
bronchopneumonia or lobar disease
- CBC: leukocytosis.
Not RSV
- rhinorrhea and pharyngitis, followed in 1-3 days by a cough and wheezing.
Auscultation of the lungs will reveal diffuse rhonchi, fine crackles, and wheezes, but the
chest film is often normal.
- If the illness progresses, coughing and wheezing increase, air hunger and intercostal
retractions develop, and evidence of hyperexpansion of the chest is seen.
- WBC count will be normal or elevated, and the differential may be
normal or shifted either to the right or left.
- Chlamydial infections can be differentiated from respiratory
syncytial virus infections by a history of conjunctivitis, the subacute onset and absence
of fever, and the
mild wheezing. There may also be eosinophilia.
Not Parainfluenza virus infection
- typical cold symptoms.
- Eight percent of infections affect the upper respiratory tract.
- In children hospitalized for severe respiratory illness, parainfluenza viruses account for
about 50% of the cases of laryngotracheitis and about 15% each of the cases of
bronchitis,
bronchiolitis, and pneumonia.
,One day after a nurse performs CPR on an emergency-department patient, she learns
that the patient had meningococcal meningitis. Which one of the following is the most
appropriate chemoprophylaxis for this condition? (check one)
A. Penicillin G benzathine (Bicillin LA), 1.2 million units intramuscularly
B. Rifampin, 600 mg every 12 hours for 2 days
C. Oral prednisone, 40 mg daily for 5 days
D. Quadrivalent meningococcal vaccine
E. No prophylaxis - Answers -B. Rifampin, 600 mg q12 x 12 days
- Rifampin has been shown to be 90% effective in eliminating meningococcus from the
nasopharynx. - also minocycline and ciprofloxacin
- even high doses of penicillin may not eradicate nasopharyngeal meningococci.
- Meningococcal vaccine appears to have clinical efficacy, but it usually takes more than
5 days to become effective.
A 30-year-old ill-appearing male presents with right hand and arm pain and a rapidly
expanding area of redness. On examination he temp is 38.9°C (102.0°F), a pulse rate of
120beats/min, and a blood pressure of 116/74 mm Hg. He also has erythema from the
dorsal hand to the elbow, violaceous bullae on the dorsal hand and wrist, and severe
pain with dorsiflexion of the wrist or fingers.
Which one of the following is the most appropriate initial step in the management of this
patient?
A. Oral dicloxacillin and outpatient follow-up within the next 24 hours
B. Intravenous metronidazole
C. Consultation with an infectious disease specialist
D. Immediate surgical consultation for operative debridement
E. Incision and drainage with wound cultures in the emergency department - Answers -
D. Immediate surgical consultation for operative debridement
- Severe pain and skin changes outside the realm of cellulitis, including bullae and
deeper discoloration, are strong indications of necrotizing fasciitis.
- Antimicrobial therapy is essential but is not sufficient by itself; aggressive surgical
debridement within 12 hours reduces the risk of amputation and death.
You are the medical director of a long-term-care facility that has 60 residents. Several
patients experience fever, cough, and upper respiratory symptoms. Two of these
patients test positive for influenza A (H1N1) virus.
Which one of the following is recommended by the Centers for Disease Control and
Prevention
(CDC) for this situation?
A. Chemoprophylaxis with appropriate medications for all residents
B. Treatment initiated on an individual basis once testing confirms that a resident has
influenza
C. Prophylaxis only for staff who have had direct patient contact with a resident with
laboratory-confirmed infection
D. No chemoprophylaxis for staff or residents who have been appropriately vaccinated
- Answers -A. Chemoprophylaxis with appropriate medications for all residents
, = two or more laboratory-confirmed cases of influenza A = outbreak in a long-term care
facility.
The CDC has specific recommendations for managing an outbreak, which include
chemoprophylaxis with an appropriate medication for all residents who are
asymptomatic and treatment for all residents who are symptomatic, regardless of
laboratory confirmation of infection or vaccination status.
- All staff should be considered for chemoprophylaxis regardless of whether they have
had direct patient contact with an infected resident or have received the vaccine.
- Requesting restriction of visitation is recommended; however, it cannot be strictly
enforced due to residents' rights.
A 54-year-old male presents to your office with a 10-day history of increasing cough. A
physical
examination reveals coarse crackles in the left lower lobe. You make a diagnosis of
pneumonia.
The patient's only current medication is simvastatin (Zocor).
Which one of the following is CONTRAINDICATED in this patient?
(check one)
A. Amoxicillin/clavulanate (Augmentin)
B. Azithromycin (Zithromax)
C. Clarithromycin (Biaxin)
D. Doxycycline
E. Levofloxacin (Levaquin) - Answers -C. Clarithromycin
- In older adults, coprescription of clarithromycin or erythromycin with a statin that is
metabolized by CYP 3A4 (atorvastatin, simvastatin, lovastatin) increases the risk of
statin toxicity. The other antibiotics listed do not interact with statins
A 30-year-old female with a history of prolonged QT syndrome presents with severe
acute
bacterial sinusitis. Which one of the following antibiotics should be avoided? (check
one)
A. Amoxicillin
B. Clarithromycin (Biaxin)
C. Amoxicillin/clavulanate (Augmentin)
D. Moxifloxacin (Avelox)
E. Cefuroxime (Ceftin) - Answers -B. Clarithromycin (Biaxin)
- Clarithromycin interferes with the delayed rectifier potassium current, which results in
the accumulation of potassium ions in cardiac myocytes and thereby delays cardiac
repolarization.
Clarithromycin is
- metabolized by the cytochrome P450 3A enzyme. When using clarithromycin it is
important to avoid any other medications that may inhibit this enzyme, leading to higher
clarithromycin levels. The other antibiotics listed do not have this effect.
A 4-week-old white male is brought to your office with a 2-week history of increasing
dyspnea, cough, and poor feeding. The child appears nontoxic and is afebrile. On
examination you note conjunctivitis, and a chest examination reveals tachypnea and
crackles. A chest film shows hyperinflation and diffuse interstitial infiltrates and a WBC
count reveals eosinophilia.
What is the most likely etiologic agent? (check one)
A. Staphylococcus species
B. Chlamydia trachomatis
C. Respiratory syncytial virus
D. Parainfluenza virus - Answers -B. Chlamydial pneumonia
- usu in infants 3 - 16 wks; pt sick for weeks
- infant nontoxic & afebrile, tachypneic w/ prominent cough
- physical examination: diffuse crackles with few wheezes, and conjunctivitis (50% of
cases).
- CXR: hyperinflation and diffuse interstitial or patchy infiltrates.
Not Staphylococcal pneumonia
- fever, initial expiratory wheeze like bronchiolitis
- PE: abdominal distress, tachypnea, dyspnea, and localized or diffuse
bronchopneumonia or lobar disease
- CBC: leukocytosis.
Not RSV
- rhinorrhea and pharyngitis, followed in 1-3 days by a cough and wheezing.
Auscultation of the lungs will reveal diffuse rhonchi, fine crackles, and wheezes, but the
chest film is often normal.
- If the illness progresses, coughing and wheezing increase, air hunger and intercostal
retractions develop, and evidence of hyperexpansion of the chest is seen.
- WBC count will be normal or elevated, and the differential may be
normal or shifted either to the right or left.
- Chlamydial infections can be differentiated from respiratory
syncytial virus infections by a history of conjunctivitis, the subacute onset and absence
of fever, and the
mild wheezing. There may also be eosinophilia.
Not Parainfluenza virus infection
- typical cold symptoms.
- Eight percent of infections affect the upper respiratory tract.
- In children hospitalized for severe respiratory illness, parainfluenza viruses account for
about 50% of the cases of laryngotracheitis and about 15% each of the cases of
bronchitis,
bronchiolitis, and pneumonia.
,One day after a nurse performs CPR on an emergency-department patient, she learns
that the patient had meningococcal meningitis. Which one of the following is the most
appropriate chemoprophylaxis for this condition? (check one)
A. Penicillin G benzathine (Bicillin LA), 1.2 million units intramuscularly
B. Rifampin, 600 mg every 12 hours for 2 days
C. Oral prednisone, 40 mg daily for 5 days
D. Quadrivalent meningococcal vaccine
E. No prophylaxis - Answers -B. Rifampin, 600 mg q12 x 12 days
- Rifampin has been shown to be 90% effective in eliminating meningococcus from the
nasopharynx. - also minocycline and ciprofloxacin
- even high doses of penicillin may not eradicate nasopharyngeal meningococci.
- Meningococcal vaccine appears to have clinical efficacy, but it usually takes more than
5 days to become effective.
A 30-year-old ill-appearing male presents with right hand and arm pain and a rapidly
expanding area of redness. On examination he temp is 38.9°C (102.0°F), a pulse rate of
120beats/min, and a blood pressure of 116/74 mm Hg. He also has erythema from the
dorsal hand to the elbow, violaceous bullae on the dorsal hand and wrist, and severe
pain with dorsiflexion of the wrist or fingers.
Which one of the following is the most appropriate initial step in the management of this
patient?
A. Oral dicloxacillin and outpatient follow-up within the next 24 hours
B. Intravenous metronidazole
C. Consultation with an infectious disease specialist
D. Immediate surgical consultation for operative debridement
E. Incision and drainage with wound cultures in the emergency department - Answers -
D. Immediate surgical consultation for operative debridement
- Severe pain and skin changes outside the realm of cellulitis, including bullae and
deeper discoloration, are strong indications of necrotizing fasciitis.
- Antimicrobial therapy is essential but is not sufficient by itself; aggressive surgical
debridement within 12 hours reduces the risk of amputation and death.
You are the medical director of a long-term-care facility that has 60 residents. Several
patients experience fever, cough, and upper respiratory symptoms. Two of these
patients test positive for influenza A (H1N1) virus.
Which one of the following is recommended by the Centers for Disease Control and
Prevention
(CDC) for this situation?
A. Chemoprophylaxis with appropriate medications for all residents
B. Treatment initiated on an individual basis once testing confirms that a resident has
influenza
C. Prophylaxis only for staff who have had direct patient contact with a resident with
laboratory-confirmed infection
D. No chemoprophylaxis for staff or residents who have been appropriately vaccinated
- Answers -A. Chemoprophylaxis with appropriate medications for all residents
, = two or more laboratory-confirmed cases of influenza A = outbreak in a long-term care
facility.
The CDC has specific recommendations for managing an outbreak, which include
chemoprophylaxis with an appropriate medication for all residents who are
asymptomatic and treatment for all residents who are symptomatic, regardless of
laboratory confirmation of infection or vaccination status.
- All staff should be considered for chemoprophylaxis regardless of whether they have
had direct patient contact with an infected resident or have received the vaccine.
- Requesting restriction of visitation is recommended; however, it cannot be strictly
enforced due to residents' rights.
A 54-year-old male presents to your office with a 10-day history of increasing cough. A
physical
examination reveals coarse crackles in the left lower lobe. You make a diagnosis of
pneumonia.
The patient's only current medication is simvastatin (Zocor).
Which one of the following is CONTRAINDICATED in this patient?
(check one)
A. Amoxicillin/clavulanate (Augmentin)
B. Azithromycin (Zithromax)
C. Clarithromycin (Biaxin)
D. Doxycycline
E. Levofloxacin (Levaquin) - Answers -C. Clarithromycin
- In older adults, coprescription of clarithromycin or erythromycin with a statin that is
metabolized by CYP 3A4 (atorvastatin, simvastatin, lovastatin) increases the risk of
statin toxicity. The other antibiotics listed do not interact with statins
A 30-year-old female with a history of prolonged QT syndrome presents with severe
acute
bacterial sinusitis. Which one of the following antibiotics should be avoided? (check
one)
A. Amoxicillin
B. Clarithromycin (Biaxin)
C. Amoxicillin/clavulanate (Augmentin)
D. Moxifloxacin (Avelox)
E. Cefuroxime (Ceftin) - Answers -B. Clarithromycin (Biaxin)
- Clarithromycin interferes with the delayed rectifier potassium current, which results in
the accumulation of potassium ions in cardiac myocytes and thereby delays cardiac
repolarization.
Clarithromycin is
- metabolized by the cytochrome P450 3A enzyme. When using clarithromycin it is
important to avoid any other medications that may inhibit this enzyme, leading to higher
clarithromycin levels. The other antibiotics listed do not have this effect.
