August 17 2022

A 35-year old female presents to the ER with one week of high fever, nausea and vomiting, headache, retroorbital pain, and muscle aches. She recently returned from a family vacation to Thailand. Laboratory analysis is remarkable for WBC count of 3000 cells per microliter and a platelet count of 80,000 cells per microliter. CT head followed by lumbar puncture are both normal. Which of the following is the most appropriate treatment for this patient's likely condition?

• Doxycycline

• Quinidine gluconate + doxycycline

• Chloroquine

• Supportive care

Answer explanation

The correct answer is supportive care. This patient is presenting with Dengue, characterized by a febrile illness followed by headache, retroorbital pain, and myalgias. Classic laboratory findings are leukopenia and thrombocytopenia. Treatment is supportive.

A 13 yo female presents to your ED with unilateral facial swelling x 1 week. Her mother is very worried because along with the facial swelling she has begun drooling from the left corner of her mouth. Her vaccines are up-to-date however she received her flu shot this year. She has no cough. On examination, she has mildly tender left cheek swelling and mild left upper and lower facial weakness. She has no neck pain or tenderness. The remainder of her exam is unremarkable including ENT exam. Vital signs are BP 112/74, HR 70bpm, RR 14, Sat 100% on RA, T 38.5C (101.3F). In the exam room she is smiling and playing with her older sibling. Which of the following do you expect to be abnormal.

• Bacterial blood culture

• Rapid Influenza PCR

• Rapid streptococcal antigen

• Amylase

Answer explanation

Amylase is often elevated in cases of parotitis. Parotitis can be caused by a number of organisms but grossly can be divided into suppurative, non-suppurative and non-infectious. Non-suppurative cases are most classically caused by the mumps virus but can also be caused by the influenza virus, coxsackie virus, Epstein-Barr virus, parainfluenza virus and CMV. Suppurative cases are generally bacterial and have a more toxic presentation classically affecting the dehydrated elderly patient. Non-infectious causes range from collagen vascular disease to sialolithiasis. Regardless of the cause, swelling of the parotid gland is expected to produce an increased serum amylase.

A 42 year old male with known HIV presents to the Emergency Department with a chief complaint of headache for 2 weeks. He reports he has been out of his HIV medications for the last 2 months, but does not recall the names. Vital signs are: BP 100/67 HR 92 RR 16 T 100.6F (38.1C). Laboratory testing is significant for a CD4 count of 87. An image from a noncontrast CT head is shown. Which of the following is the most likely etiology of his headache?

• CMV encephalitis

• CNS lymphoma

• Progressive multifocal leukoencephalopathy

• Cerebral toxoplasmosis

Answer explanation

The patient has HIV, and has a low CD4 count, <100, which increases his risk for CNS toxoplasmosis. The other answer choices are seen with a CD4 count <50.

Additionally, the noncontrast head CT image demonstrates multiple hypodense regions with perifocal edema. The classic "ring-enhancing" lesions are found in head CT performed WITH contrast. In noncontrast CT head imaging, cerebral toxoplasmosis appears as multiple, hypodense regions predominantly in the basal ganglia and corticomedullary junction.

A 13-year-old boy presents for evaluation of a fever for 2 days. His parents also note decreased appetite and malaise. His vitals on arrival to the emergency department are T 38.6°C, HR 123 bpm, BP 90/50 mm Hg, and 98% saturation on room air. His physical examination is notable for the skin findings shown above and shallow ulcers on the tongue and buccal mucosa. Which of the following is a complication of this patient’s condition?

• Coronary artery aneurysm

• Encephalitis

• Orchitis

• Rheumatic heart disease

Answer explanation

This patient is presenting with a rash consistent with infection with varicella-zoster virus (VZV).

nfants, immunocompromised children, and those over the age of 12 who have not been vaccinated are at increased risk of complications from infection, which include viral pneumonia, hepatitis, and encephalitis. Supportive therapy is sufficient for those at low risk of the development of complications, but antiviral therapy should be used in those who are at high risk for developing complications from the infection.

Which of the following patients who tested positive for SARS-CoV-2 is most likely to benefit from monoclonal antibody treatment?

• 13-year-old unvaccinated girl admitted for severe anorexia who weighs 38 kg

• 14-year-old boy with leukemia hospitalized for hypoxia and respiratory distress

• 16-year-old vaccinated girl who is asymptomatic but tested after an exposure

• 17-year-old unvaccinated boy with sickle cell disease admitted for appendicitis

Answer explanation

When a monoclonal antibody treatment effective against the circulating variant of SARS-CoV-2 is available, it should be offered to patients with mild to moderate illness who are at high risk of progression to serious disease.

Monoclonal antibody treatment should not be used for preexposure prophylaxis or in patients with serious illness from SARS-CoV-2 (e.g., new hypoxia). It is not approved for children < 12 years of age or < 40 kg, except for neonates.

An 18-year-old college student with a history of HIV (CD4⁺ 250) presents to the ED with headache, fever, and stiff neck for two days. He thought he had a cold and has been taking acetaminophen without relief of his headache. Vital signs are T 102.38°F (39.1°C), BP 100/50 mm Hg, HR 140 bpm, and RR 30/min. He is sleepy but arousable. On exam, you place the patient’s right hip and knee into a flexed position and then proceed to extend the knee. The patient winces when the knee is just beyond 90 degrees of flexion. You also note petechiae on his trunk and extremities with one small area on his right forearm that looks like a purple patch with a gray necrotic center. Which of the following is the most likely diagnosis?

• Cryptococcal meningitis

• Herpes encephalitis

• Meningococcemia

• Pneumococcal meningitis

• Toxoplasmosis

Answer explanation

This patient has meningococcemia, a disease caused by Neisseria meningitidis.

Petechiae generally appear on the extremities and may progress to involve almost any body surface. Macular lesions may progress to purpura and ecchymoses in fulminant meningococcemia (purpura fulminans). The patient in this scenario exhibits a positive Kernig sign, representing meningeal irritation, and has a purpuric lesion on his right forearm characterized by a gray necrotic center surrounded by a purple ring.

Ceftriaxone and vancomycin are acceptable first-line agents.

A 67-year-old female with history of mitral valve prolapse presents to the Emergency Department with generalized malaise, 20 pound weight loss and intermittent fevers for the past three weeks after simple dental extraction. Her vitals are BP 145/88, P 89, RR 15 O2S at 98%, T101.5 (38.6C). Other than a mid-to-late systolic click at the cardiac apex, her physical exam is largely unremarkable. EKG and chest x-ray are normal. Blood cultures in addition to labs studies are drawn and broad-spectrum antibiotics started. What is the next best step in managing this patient?

• Cardiac CT

• ESR/CRP

• Cardiac MRI

• Transesophageal echo (TEE)

• Transthoracic echo (TTE)

Answer explanation

Transthoracic echo is the initial imaging study of choice for patients with suspected endocarditis. While it is not as sensitive as TEE, it is far less invasive and is still 60-70% sensitive and 100% specific for infective endocarditis. If negative and infective endocarditis is still suspected, additional imaging can be obtained. Daniel WG, et al: Comparison of transthoracic and transesophageal echocardiography for detection of abnormalities of prosthetic and bioprosthetic valves in the mitral and aortic positions.

A 33-year-old male with a history of HIV presents to the emergency department with fever and generalized weakness. He is not compliant with his medications and his last CD4 count was less than 50 cells/µL. Laboratory analysis is significant for pancytopenia. What is the most likely etiology of this patient’s presentation?

• Cryptosporidiosis

• Mycobacterium avium complex

• Pneumocystis Jirovecii (PCP)

• Toxoplasmosis

Answer explanation

The correct answer is Mycobacterium avium complex. This is one of the most common causes of fever of unknown origin in the AIDS patient and can cause bone marrow suppression and pancytopenia.

A 53-year old patient is brought in by ambulance to the Emergency Department from the street for altered mental status. He is disoriented and yelling about "the mafia" and "ghosts", with waxing and waning belligerence. Vitals signs are BP 141/89, P 118, R 16, T 101.2F (38.4C), O2 saturation 99%RA. After chemical sedation, the patient was sent to radiology for a CT scan of the head. The technician accidentally completed the CT scan with contrast, which showed several ring-enhancing lesions. A rapid HIV test results positive. Which of the following is considered first-line therapy in the treatment of this patient?

• Amphotericin B

• Methotrexate

• Pyrazinamide

• Pyrimethamine

Answer explanation

This patient likely has cerebral toxoplasmosis given the fever, altered mental status, ring-enhancing lesions on CT, and HIV positive result. Pyrimethamine is an anti-protozoal drug used to treat Toxoplasma gondii, which manifests itself as an opportunistic infection in HIV or other immunocompromised patients. The first-line treatment regimen actually consists of pyrimethamine + sulfadiazine + leucovorin, or pyrimethamine + clindamycin. The major differential diagnoses to consider in HIV-patients with ring-enhancing lesions is CNS lymphoma versus cerebral toxoplasmosis. However, in the setting of fever, toxoplasmosis is more likely. Of note, pyrimethamine has many side effects, including Stevens-Johnson Syndrome.

A 34 year old male presents to the Emergency Department with general feeling of malaise, fatigue, and headaches for one week. The patient denies pharyngitis or cough. The patient denies any past medical or surgical history. Vitals signs are: BP 120/87, HR 102, RR 14, T 101.2F (38.4C). Social history is significant for unprotected sex with multiple male and female partners. Which of the following is TRUE regarding this patient's likely underlying disease process?

• Seroconversion is complete by 4 weeks

• Serum viral load will likely be negative

• Viral antibody test will likely be negative

• Viral transmission to other patients begins after patient's seroconversion phase

Answer explanation

The patient has an acute HIV infection, which is characterized by fever, fatigue, headache, and occasionally a rash. It is often confused for influenza viral infection given its nonspecific symptom constellation. He has a significant risk factor for HIV infection and should be tested, although during the acute HIV infection (first 2-3 months) the HIV antibody test may be negative. However, the serum HIV viral load is often detectable and can be quite high.

Technically, acutely infected HIV patients can transmit/infect HIV to another person at any time during the patient's acute HIV infection, although the patient is highly infectious during the 3rd-4th week of acute HIV infection, when genital shedding of HIV virus peaks.

Seroconversion is generally complete by 10-24 weeks - that is, initial host immune response to HIV is complete, signaled by the serum HIV antibody test first becoming positive in the patient.