28 terms

Case Studies

ID Exam 3
22 y/o male, 10 year history of IVDU. Presents with severe cough. Treated for CAP with Levofloxacin. HIV test comes back (+) and BAL catheter yields PCP. Without knowning CD4/viral load, what treatment is recommended?
TMP/SMX 15-20mg/kg/d IV q6h x 21 d
If he is profoundly hypoxic, make sure to add steroids - Methylprednisolone 40mg IV q12h x 3-4 days, then prednisone tapered down over 21 days
After further investigation, we find that the patient has a sulfa allergy. How does treatment change?
Prefer 2nd line treatment of Clindamycin + Primaquine but this is a PO regimen, and if the patient is on a ventilator, we'd have to go with option #3 - Pentamidine 4mg/kg/d IV x 21d
Also, if patient is severely ill, only use this alternate tx for a day or two, and then try to desensitize the patient to TMP/SMX
Over the next 2 weeks, the patient improves, completes his antibiotics, and is about to go home. His CD4 count is 150 cells/uL. Does he require prophylaxis, if so, with what?
Yes b/c his CD4 is <200. If we get his CD4 >200 for 3 months, then he can come off tx.
Treat prophylactically with TMP/SMX ss po qd or ds po tiw.
If the sulfa allergy couldn't be overcome, treat with Clindamycin + Primaquin first, then use Dapsone. If he drops to <100, add pyrimethamine (to cover Toxoplasmosis)
If a patient has been getting treated prophylactically with TMP/SMX for PCP, but then gets a PCP infection, can we still use TMP/SMX for treatment?
Yes, because you will be using much higher doses. There are very few, if any, cases of resistance of PCP to Bactrim. Almost always get full response.
Patient comes back and has been forgetting to take his antiretrovirals. His CD4 is 68 cells/uL. What prophylaxis should he receive? What if he has a sulfa allergy?
Now at risk for Toxo. He was already on Dapsone, so add pyrimethamine to cover the toxo, with adjunctive Leucovorin. If he didn't have a sulfa allergy, Bactrim would be the better choice.
Patient does well for several years, but eventually his CD4 count drops to 23 cells/uL and he presents with a severe HA. Cryptococcus antigen comes back @ 1:64. How do you treat him initially? What treatment other than antifungals will you use?
2 Weeks of Amphotericin B + flucytosine, follwed by 8 weeks of fluconazole.
Adjunct therapy is lumbar puncture until CSF is not elevated more than ~50% above normal.
A 50 y/o male presents with persistant cough with productive, bloody sputum for the past month. He has lost 10lbs over the summer. He admits to "hot-boxing" and states that some of his friends are also coughing up bloody sputum. What are some s/sx of TB in this patient?
Weight loss, cough, bloody sputum, transmission risk given hx
Patient expresses AFB in sputum, CXR demonstrates cavitary lesions. What infection control procedures are recommended?
Isolate the patient in a negative airflow room and have attending staff wear high efficiency masks
What regimen do you start this patient on?
4 Drug regimen: INH + RIF + PZA + EMB
One of the patients friends shows no signs of active TB, but has an 18mm induration from a PPD test. What do we recommend for this person?
Latent infection - start with INH 300mg qd x 6 mo.
NS, a 36 y/o male with active TB has received 1 week of therapy with INH, RIF, PZA, and EMB when he has an acute gout attack. Which drug do you want to dump?
If liver enzymes were severely elevated, you would also want to get rid of this drug.
A week later he complains of distressing visual disturbances. Now which drug goes?
NS forgot to tell his doctor about his HBV infection and now his liver needs some relief. Construct a gentler regimen for NS.
Assuming he was on INH, RIF, PZA, and EMB:
Use Streptomycin in place of PZA b/c it has little to no hepatotoxicity (don't want to change INH or RIF unless absolutely necessary)
JS presents with a whole lotta diarrhea. Is CD4 count is 18 cells/uL. What are the potential etiologies of his diarrhea?
Cryptosporidiosis, Microsporidiosis
His drug regimen - PI's and HIV itself can cause a malabsorptive syndrome in the GIT
Testing reveals that the patient has active MAC, CMV, and cryptosporidiosis. How do you approach treating this patient?
MAC: Clarithromycin + EMB + Rifabutin
CMV: IV Ganciclovir (make adjustments as necessary)
Cryptosporidiosis - put patient back on his antiretrovirals but be cautious b/c PCP, MAC, and CMV put him at an increased risk of IRIS
JS responds to therapy and is about to be discharged with a CD4 <50 cells/uL. What prophylactic tx do you recommend?
PCP - Bactrim ss po qd or ds po tiw
If sulfa allergy, Dapsone + Pyrimethamine + Leucovorin (the Pyrimethamine will cover Toxo)
MAC - continue 3 drug regimen (Clarithromycin + EMB + Rifabutin)
If he hadn't had active MAC, would give Azithromycin once a week for prophylaxis
CMV (+) so keep on Valgancyclovir or Gancyclovir
A 25 y/o male comes to ER with severe sepsis. His girlfriend states he has had flu-like s/sx including fever and a new onset heart murmur within the past 2 days. Bilateral pulmonary emboli are noted to be present after CXR. Hx shows IVDU for 6+ years. Cultures show 3 sets of 3 G(+) clusters. TEE shows vegetation on tricuspid valve. What is the suspected organism?
Acute or subacute endocarditis?
Acute - will lose valve
When treating do we cover MRSA?
Yes, 50% are MRSA so use Vanco - aggressive doses (troughs 15-20 mcg/mL). May also consider adding rifampin 300-600mg q12h to up the killing potential.
If cultures come back as MSSA. New recommendation?
Nafcillin or oxacillin, highest dose possible - 2g q4hr
If the patient is PCN allergic but not anaphylactic give Cefazolin or Ceftriaxone 6g q24hr IV in divided doses.
If cultures come back as MRSA, new recommendation?
Vanco MIC must be < or = 2 mg/L
Continue on same regimen of Vanco + Rifampin
Daptomycin alternate if it was VRSA
How long do we treat this patient with antibiotics?
For both MSSA and MRSA, for 4-6 weeks
OO was shot in the abdomen. He is taken immediately to surgery where the bowel is repaired and the peritoneal cavity is washed out and vessels are repaired to stop the bleeding. His vitals on admission are HR 135, BP 72/58. What is your initial therapeutic approach both before and during surgery?
Initial approach - fluids, maybe colloids
What organisms do you anticipate for the infection?
(G-'s and anaerobes mostly) E. coli, B. fragilis, G+'s from surgery
What empiric antibiotics would you recommend?
1. Cefoxitin (prophylaxis)
2. Metronidazole + Cipro for allergy
3. Metronidazole + Ceftriaxone or Ceftazadime
4. Pip/Tazo
5. Ertapenam
Despite aggressive fluid resuscitation OO remains hypotensive. What do you recommend now and why?
Vasopressors and steroids (assuming hypotensive b/c adrenal is suppressed)
OO was given prophylactic ab's with amp/sulbactam. On day 1 after surgery his vitals are: HR 79, BP 110/70, Tmax (temp) 99.8, and SCr 1.0. Now what is your therapeutic approach?
Maintain treatment - patient seems to be responding
4 Days later OO is getting ready to go home but spikes a temperature of 101.6. He is pan-cultured and undergoes a CT scan which reveals multiple abdominal abscesses and blood Gram's stain shows G(-) rods. Over the next several hours his condition rapidly deteriorates. What is likely causing OO to be hypotensive?
Pro-inflammatory cytokines (TNF-a, IL-1, IL-6)