IDBR Infectious Disease Board Review

A 43-year-old man is admitted with acute onset of right sided hemiplegia and dysarthria. He had been in excellent health until one month previously when he presented with shortness of breath and was diagnosed with acute pulmonary emboli and adenocarcinoma of the lung. He was begun on eliquis and chemotherapy was deferred pending genetic testing.

The patient lives with his wife and 2 children in Chicago. He works as a municipal bus driver. He denies pet or animal exposure. On presentation, he is afebrile. Exam is notable for poor dentition and dense right hemiplegia.

CT head confirmed a left middle cerebral artery infarct.

TTE confirms a 6x9 mm mass on the mitral valve.

Blood cultures x3 sets taken prior to initiation of antibiotics are no growth at 5 days.

What is the most probable cause of endocarditis in this patient?

A. T whipplei

B. Mycobacterium chimaera

C. Bartonella henselae

D. Hypercoaguable state

E. Coxiella burnetii

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A 58-year-old HIV- negative gay man is evaluated for PrEP. His past medical history is notable for hypertension, treated for over 10 years with an ACE inhibitor. He is asymptomatic and weighs 145 lbs.

He is sexually active with multiple partners but “usually” practices safe sex.

Lab studies reveal: HIV 4th generation test negative, HIV-1 RNA negative, CBC normal, creatinine 1.4 with a

calculated creatinine clearance of 48 ml/min.

What do you recommend for PrEP?

A. No PrEP

B. Tenofovir disoproxil fumarate/emtricitabine 1 pill daily

C. Tenofovir disoproxil fumarate/emtricitabine 1 pill every other day

D. Tenofovir alafenamide/emtricitabine 1 pill daily

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A 44-year-old man was diagnosed with Pneumocystis pneumonia as his AIDS-defining illness and begun on antiretroviral therapy with 2 nucleosides and an integrase inhibitor during his hospitalization. He stabilizes and follows up for repeated outpatient visits with an HIV RNA consistently <20 copies/ml and a CD4 cell count of 44 that increased to 163 (at 3 months), 232 (at 6 months), 242 (at 9 months), and was repeated at 243 (at 12 months).

His current medications are: tenofovir alafenamide/emtricitabine, dolutegravir, trimethoprim-sulfa double strength daily, and azithromycin 1200 mg once weekly. He says he’s tired of taking pills and would like to stop some of them.

What do you recommend?

A. Stop tenofovir alafenamide/emtricitabine

B. Stop trimethoprim-sulfa

C. Stop azithromycin

D. Stop trimethoprim-sulfa and azithromycin

E. Continue the current regimen

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A 29-year-old man living with HIV on tenofovir alafenamide (TAF)/emtricitabine + dolutegravir (CD4 298, HIV RNA <20 cps/ml) develops pulmonary TB.

The plan is to start empiric INH, RIF, PZA, and ETH pending mycobacterial susceptibilities.

How do you manage his ART regimen?

A. Continue current regimen

B. Change dolutegravir to darunavir/ritonavir

C. Change dolutegravir to elvitegravir

D. Double the dose of dolutegravir

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A 56-year-old male with end-stage-renal disease due to hypertensive nephropathy is being evaluated for possible renal transplantation.

Routine pre-transplant serologies were obtained, which were notable for a positive Interferon-Gamma Release Assay (IGRA) for Mycobacterium tuberculosis. The patient is asymptomatic and has never been treated for TB.

Chest x-ray is normal.

The patient has a suitable living donor and the transplant team would like to proceed with transplantation as soon as possible.

Which one of the following would be the best course of action?

A. Inform the transplant team that patient is not a renal transplant candidate due to TB infection

B. Initiate treatment with isoniazid and vitamin B6 while proceeding with transplant; complete treatment for a total of 6-9 months

C. Initiate treatment with rifampin while proceeding with transplant; complete treatment for 4 months

D. Initiate treatment with once weekly isoniazid and rifapentine while proceeding with transplant; complete treatment for 12 weeks

E. Initiate treatment with isoniazid, rifampin, pyrazinamide and ethambutol for 6 months while proceeding with transplant

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A 63-year-old male underwent allogeneic stem cell transplant for chronic myelogenous leukemia 120 days

ago. He has had multiple episodes of acute graft-versus-host disease, for which he received multiple pulses

of corticosteroids and remains on maintenance cyclosporine. His absolute neutrophil count hovers

between 750 and 1000 cell/μL. He is receiving prophylactic doses of trimethoprim-sulfamethoxazole.

The patient developed a fever, patchy pulmonary infiltrates and hypoxia. He is intubated and undergoes

bronchoscopy. The micro lab reports that branched hyphae are present on wet mount of the BAL. No

pneumocystis was seen. PCR on the BAL is positive for CMV. Liposomal amphotericin (5 mg/kg/day) is

started.

Five days later, the lab reports that the BAL culture is growing Scedosporium apiospermum. PCR of

peripheral blood for CMV is undetectable. The patient is still febrile and the pulmonary status has

deteriorated.

At this point, you would recommend:

A. Raise the dose of liposome amphotericin B to 10 mg/kg

B. Add ganciclovir

C. Switch to fluconazole

D. Switch to voriconazole

E. Add caspofungin

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A 42-year-old woman newly diagnosed with HIV (CD4 425, HIV RNA 73,000, genotype with wild-type virus) starts tenofovir alafenamide/emtricitabine/bictegravir and has the following virologic response:

Weeks of Therapy HIV Viral Load

4 weeks HIV RNA 9,400

8 weeks HIV RNA 1,050

16 weeks HIV RNA 105

24 weeks HIV RNA 90

36 weeks HIV RNA 67

48 weeks HIV RNA 82

In addition to reinforcing adherence, what would you recommend?

A. Add darunavir/ritonavir

B. Add etravirine

C. Add darunavir/ritonavir and etravirine

D. Switch bictegravir to darunavir/ritonavir

E. Continue current regimen

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A 36-year-old obese white man (BMI 34) recently diagnosed with HIV (CD4 560, HIV RNA 52,000) is recommended to start antiretroviral therapy but is concerned about weight gain.

Which is true of antiretroviral-induced weight gain?

A. Raltegravir is associated with more weight gain than dolutegravir

B. Elvitegravir is associated with more weight gain than bictegravir

C. Tenofovir AF is associated with more weight gain than tenofovir DF

D. White men have the highest rates of weight gain on ART

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A 52-year-old woman with no prior medical conditions presents with a 6-month history of shortness of breath and cough. She has no fever, and her CBC and Chemistry panel is normal. Oxygen saturation on room air = 80%.

She reports that she installed a hot tub at home which she uses daily; she has no other unusual exposures.

If this syndrome is related to her hot tub, which of the following organisms is most likely related to the pulmonary process?

A. Acanthamoeba

B. Legionella pneumophila

C. Aeromonas hydrophila

D. Mycobacterium avium complex

E. Nocardia asteroides

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A 62-year-old nurse presents to your clinic with a six-month history of pain and swelling involving her third

finger.

She has been treated sequentially with cephalexin, amoxicillin-clavulanate, and clindamycin without effect.

She is an avid gardener and enjoys digging for clams in a marshy area near to her home. She admits to

frequent abrasions and scratches.

MRI has demonstrated diffuse soft tissue inflammation with tenosynovitis, septic arthritis of the

interphalangeal joints, and early phalangeal osteomyelitis.

What is the most likely microbiologic agent?

A. Methicillin-resistant Staphylococcus aureus

B. Aeromonas hydrophila

C. Nocardia nova complex

D. Nontuberculous mycobacteria

E. Sporothrix schenckii

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