Surgical Critical Care and Emergency Surgery. Группа авторов

This wound would be classified as a moderate diabetic foot infection and therefore should be treated with antibiotics. In a moderate diabetic foot infection, aerobic GPCs, MSSA, Streptococcus spp., Enterobacteriaceae, and other obligate anaerobes are the likely pathogens. These are all adequately covered by ertapenem. Initiation of vancomycin and piperacillin/tazobactam would be a correct answer if this patient had a severe diabetic foot infection. She does not require any further coverage for MRSA or pseudomonal infections as she does not have any current risk factors, nor is her illness severe enough to prompt broad‐spectrum empiric antibiotic coverage.Initial imaging of a diabetic foot infection should always be an x‐ray of the foot, which is both sensitive and specific for osteomyelitis. If any diagnostic uncertainty remains following the x‐ray, an MRI can be pursued.Answer: DLipsky BA., Berendt AR, Cornia PB, et al. 2012 Infectious Diseases Society of America Clinical Practice Guideline for the Diagnosis and Treatment of Diabetic Foot Infections, Clin Infect Dis. 2012; 54 12: e132–e173, https://doi.org/10.1093/cid/cis346

      18 A 67‐year‐old male who has returned 6 weeks ago from a trip to New England where he had been trail‐running in preparation from a marathon presents to the ED complaining of intractable fatigue, dark‐reddish urine, and frequent high fevers at home. He reveals that he had pulled a small bug off his arm during his trip and that he did not notice any associated rash. He has splenomegaly on physical exam. His labs return showing a normocytic anemia with elevated transaminases. A Wright’s/Giemsa stain of his peripheral blood demonstrates darkly stained rings with light blue cytoplasm within erythrocytes. The most likely disease responsible for his condition is:Lyme diseaseBabesiosisRocky Mountain Spotted FeverEhrlichiosisAnaplasmosisThis patient has babesiosis, more specifically an infection with the parasite Babesia microti. B. microti is an intraerythrocytic parasite that is transmitted from ticks to vertebrates including humans. The disease contracted by the host can be broad with varying symptoms ranging from asymptomatic infection to a disease like malaria with severe hemolysis and death. Symptoms can take months after exposure to develop. Common signs and symptoms of babesiosis are fatigue, anemia, fevers, chills, night sweats, hemoglobinuria, transaminitis, weight loss, hepato/splenomegaly. Diagnosis is typically made with exposure to ticks, stained blood smears, and ELISA/PCR. The standard treatment for babesiosis is clindamycin and quinine. In a serious infection where clindamycin and quinine are not sufficient, there has been some benefit shown in erythrocyte exchange transfusion.Lyme disease is the most common tick‐borne illness in the United States and is also hosted by the Ixodes tick. It is known for its characteristic bull’s‐eye rash (erythema migrans), but this is not present in all cases. Lyme disease commonly presents with low‐grade fevers and myalgias. The disease, however, can disseminate and affect the musculoskeletal, neurologic, and cardiovascular system. Most commonly, musculoskeletal symptoms are present in Lyme disease in the form of migratory joint and muscle pain. Anemia is not associated with Lyme disease, and this spirochete bacterium is not apparent on a peripheral blood smear. Treatment for Lyme disease is typically doxycycline for adults and amoxicillin for children.Rocky Mountain Spotted Fever is a serious disease that is caused by Rickettsia rickettsii and transmitted after a tick bite. It is most common in the southeastern and south‐central United States. This bacterium preferentially infects the vascular endothelial cells of small and medium vessels in the body. Patients typically present 4–10 days post exposure and have fever, headache, and a rash. Typically, patients are treated empirically based on their history and physical with doxycycline, but PCR can be performed to confirm diagnosis.Ehrlichiosis is a tick‐borne disease carried by the Lone Star Tick found in the south‐central United States. Ehrlichiosis is associated with fever, headache, body aches, malaise, and chills but can include gastrointestinal symptoms, respiratory symptoms, and rash. Associated laboratory findings include leukopenia, thrombocytopenia, hyponatremia, and moderately elevated transaminases. Diagnosis is made clinically or by PCR. Treatment is doxycycline.Anaplasmosis is transmitted by the Ixodes tick and is found worldwide; it is caused by Anaplasma phagocytophilum – an obligate intracellular bacterium. Symptoms include fever, malaise, myalgias, and headache with some patients experiencing nausea, vomiting, diarrhea, cough, arthralgias, and confusion. Rash is uncommon in anaplasmosis. Anaplasmosis is visible on peripheral blood smear, and it can be seen within the neutrophils in aggregates called morulae. Doxycycline is the first line treatment for anaplasmosis.Answer: BGuzman N, Yarrarapu SNS, Beidas SO. . Anaplasma Phagocytophilum. [Updated 2021 Jan 5]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513341/Homer MJ, Aguilar‐Delfin I, Telford SR III, et al. Babesiosis. Clin Microbiol Rev. 2000; 13(3):451–69. doi: 10.1128/cmr.13.3.451‐469.2000. PMID: 10885987; PMCID: PMC88943.Snowden J, Simonsen KA, Rickettsiae Rickettsia. [Updated 2020 Nov 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430881/Snowden J, Bartman M, Kong EL, et al. Ehrlichiosis. [Updated 2020 Sep 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441966/Bratton RL, Whiteside JW, Hovan MJ, et al. Diagnosis and treatment of Lyme disease. Mayo Clin Proc. 2008; 83(5):566–71. doi: 10.4065/83.5.566. PMID: 18452688

10 Pharmacology and Antibiotics

       Michelle Strong, MD, PhD1 and Elaine Cleveland, MD2

       1 Trauma and Acute Care Surgeon, Austin, TX, USA

       2 William Beaumont Army Medical Center, El Paso, TX, USA

      1 A 64‐year‐old man with a past medical history notable of hypertension, hyperlipidemia, peripheral vascular disease, and diabetes presents with copious purulent drainage coming from his right trans‐metatarsal amputation site. He has been spiking fevers for the last two days; his white blood cell count is 24 000, and his blood pressure is 95/40 mm Hg. Previous cultures at the time of his amputation 3 months ago grew extended spectrum beta‐lactamase (ESBL) Enterobacteriacea. What antibiotic should you start this patient on (assuming normal renal function)?Ampicillin/sulbactam 3 gm every 6 hrsCeftriaxone 1gm every 24 hrsPiperacillin/tazobactam 4.5 every 8 hrs (extended infusion)Cefepime 2 gm every 12 hrsMeropenem 1 gm every 8 hrsESBLs are plasmid‐mediated enzymes that inactivate all β‐lactam antibiotics including penicillins, third‐ and fourth‐generation cephalosporins (ceftriaxone and cefepime, respectively), and monobactams. Carbapenems and cephamycin are effective against ESBLs. Detection of ESBLs is often difficult and some microbiology laboratories do not employ reliable methods, which may result in false susceptible reporting of ESBL strains to cefotaxime, ceftazidime, and ceftriaxone. Cefepime, a fourth‐generation cephalosporin, does not appear to induce this type of chromosomal‐mediated resistance to the same degree as ceftazidime, but is susceptible to the action of ESBLs. Most ESBLs also co‐express resistance to other agents including aminoglycosides and fluoroquinolones. Carbapenems (specifically meropenem) are the most effective agents against ESBLs. An ESBL E‐test should be performed for this isolate, and the patient should be started on meropenem.Answer: EGhafourian S, Sadeghifard N, Soheili S, et al. Extended spectrum Beta‐lactamases: definition, classification and epidemiology. Curr Issues Mol Biol. 2015; 17 :11–21. Epub 2014 May 12.Nathisuwan S, Burgess DS, Lewis JS . Extended‐spectrum beta‐lactamases: epidemiology, detection, and treatment. Pharmacotherapy. 2001; 21 (8):920–928. PMID: 11718498McDaniel J, Schweizer M, Crabb V, et al. Incidence of Extended‐Spectrum β‐Lactamase (ESBL)‐ producing Escherichia coli and Klebsiella Infections in the United States: a systematic literature review. Infect Control Hosp Epidemiol. 2017; 38 (10):1209–1215. PMID: 28758612

      2 A 76‐year‐old woman with end‐stage renal disease, uncontrolled diabetes, and pain control issues has been admitted to the ICU after undergoing an open right hemicolectomy. The procedure was uncomplicated, and the patient was extubated 3 hours after admission to the surgical intensive care unit. On examination,