Question

Sallie is a 66-year-old female who presents to the emergency room with an erythematous wound on her left foot. She recounts stepping on a nail last week while walking outside. The patient was diagnosed with a diabetic foot infection and prescribed cefepime IV 2 grams every 12 hours.

Past Medical History:

Type 2 Diabetes

Hypertension

Home Medications:

Lisinopril 20 mg daily

Atorvastatin 20 mg daily

Metformin 1000mg BID

Allergies: Penicillin, reaction unknown

Left Foot Wound Culture: positive for Pseudomonas aeruginosa

10.9

140

33.2

23

189

32

101

15

1.3

18   

3.4

​   Height 5’9 Weight 160 lbs

1. Describe the factors that increase the risk of Pseudomonasinfection in MG.

2. Why are unverified penicillin allergies a concern and wouldyou process the cefepime? Why or why not?

3. Please describe the mechanism of action and pharmacodynamic properties of cephalosporins.

Answer 1

1. Myasthana gravis presents with supression of immune system therefore could aggravate Pseudomonas infection.

2. Unverified penicillin allergies are concern as they can lead to longer hospitalizations, higher costs, greater risk for adverse effects of non beta lactam antibiotics, and increased rates of serious antibiotic resistant infections. Cefepime is a fourth-generation cephalosporin antibiotic therefore it must be given in extreme cases only.

3. Mode of action of cephalosporins is throug the action of β-lactams, by impairing bacterial cell wall synthesis and hence are bactericidal. The cephalosporins differ in the substituents attached at the 3 and/or 7 positions of the molecule.