Snapshot A 55-year-old woman presents to the emergency department with fatigue and abdominal pain. Her symptoms are associated with dysuria, hematuria, and increased urinary frequency. Physical examination is remarkable for bilateral flank pain, suprapubic tenderness, and costovertebral angle tenderness. Urine studies are obtained and she is started on empiric antibiotics. Urine cultures grows Pseudomonas aeruginosa. (Pyelonephritis secondary to Pseudomonas infection) Introduction Aerobic, non-lactose fermenting, oxidase-positive, gram-negative bacillus Pathogenesis phospholipase C produced to degrade cell membranes endotoxin, which leads to fever hypotension disseminated intravascular coagulation exotoxin A this inactivates elongation factor 2 (EF-2), which stops protein synthesis via ADP ribosylation pyoverdine and pyocyanin pigment leads to a blue-green pigment Associated Conditions Conditions Comments Pneumonia - Sepsis - Ecythma gangrenosum Seen in severely ill and immunocompromised patients Urinary tract infections - Diabetes - Osteomyelitis Can be seen in patients with puncture wounds Nosocomial infections Such as catheter-associated and ventilator-associated infections Skin infections Hot tub folliculitis Wound infections in burn victims Cystic fibrosis (CF) Its mucoid polysaccharide capsule may play a role in chronic pneumonia seen in CF patients most common microbe isolated in adults with cystic fibrosis Treatment Prompt antibiotic administration is associated with improved mortality In addition to antibiotic treatment, source control is important (e.g., abscess drainage and removal of the catheter) Treatment options include carbapenems aminoglycosides monobactams polymyxins fluoroquinolones third and fourth generation cephalosporins piperacillin
QUESTIONS 1 of 4 1 2 3 4 Previous Next (M1.MC.17.4754) A 45-year-old male presents to his primary care physician complaining of drainage from his left great toe. He has had an ulcer on his left great toe for over eight months. He noticed increasing drainage from the ulcer over the past week. His past medical history is notable for diabetes mellitus on insulin complicated by peripheral neuropathy and retinopathy. His most recent hemoglobin A1c was 9.4%. He has a 25 pack-year smoking history. He has multiple sexual partners and does not use condoms. His temperature is 100.8°F (38.2°C), blood pressure is 150/70 mmHg, pulse is 100/min, and respirations are 18/min. Physical examination reveals a 1 cm ulcer on the plantar aspect of the left great toe surrounded by an edematous and erythematous ring. Exposed bone can be palpated with a probe. There are multiple small cuts and bruises on both feet. A bone biopsy reveals abundant gram-negative rods that do not ferment lactose. The pathogen most likely responsible for this patient’s current condition is also strongly associated with which of the following conditions? Tested Concept QID: 108951 Type & Select Correct Answer 1 Otitis externa 66% (75/113) 2 Gastroenteritis 9% (10/113) 3 Waterhouse-Friedrichsen syndrome 13% (15/113) 4 Rheumatic fever 4% (5/113) 5 Toxic shock syndrome 5% (6/113) M 2 Question Complexity B Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 1 Review tested concept (M1.MC.17.4723) A 37-year-old woman presents to her primary care physician after returning from her honeymoon in Cancun. A few days ago, she began to notice an eruption of small red bumps that cover her torso, back, and buttocks. The patient first thought she had acne, but became worried when the rash continued to itch. The patient denies other symptoms. Vital signs are within normal limits. Physical exam is notable for red papules and pustules scattered across the trunk, abdomen, back, and buttocks, while sparing the limbs. Closer examination indicates inflammation of the hair follicles. Culture yields motile, gram-negative rods that are non-lactose fermenting and oxidase positive. What other finding is commonly observed in the culture of the most likely organism? Tested Concept QID: 108525 Type & Select Correct Answer 1 Pink colonies 8% (18/231) 2 Blue-green pigment 58% (135/231) 3 Alpha-hemolysis 11% (25/231) 4 Yellow sulfur granules 13% (31/231) 5 Red pigment 6% (14/231) M 1 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review tested concept Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK