Infections caused by carbapenemase-producing Klebsiella pneumoniae have been reported with increasing frequency, thereby limiting the choice of effective antimicrobial agents available to clinicians. This has prompted the increased use of polymyxins and tigecycline, but resistance to these agents is already emerging. We report 2 cases of infection with panresistant K. pneumoniae.
Since carbapenemase-producing Klebsiella pneumoniae strains were first reported in North Carolina, these highly resistant organisms have been isolated with increasing frequency, especially in the New York City area. Polymyxin B is one of the few antimicrobials that retain reliable activity against these organisms. However, polymyxin B MICs are elevated against K. pneumoniae isolates with increasing frequency, leaving clinicians with few therapeutic options. We investigated several antimicrobial agents for potential synergy with polymyxin B against 12 clinical strains of carbapenemase-producing K. pneumoniae. A broth microdilution assay using a 96-well plate was developed in which graded dilutions of polymyxin B and the study drug were incubated with resistant isolates in a checkerboard pattern. Polymyxin B was studied in combination with cefazolin, ceftriaxone, cefepime, imipenem, gentamicin, tigecycline, doxycycline, and rifampin. All K. pneumoniae strains tested positive for K. pneumoniae carbapenemase (KPC) genes by real-time PCR and had elevated polymyxin B MIC values ranging from 16 to 128 g/ml. Synergy was observed with the combination of polymyxin B and rifampin as well as with polymyxin B and doxycycline, resulting in at least a 4-fold decrease in the polymyxin B MIC. For both combinations, this effect occurred at physiologically achievable concentrations. Less pronounced synergy was noted with tigecycline and polymyxin B. No synergy was observed at physiologic concentrations with the other antimicrobials studied. These results suggest that rifampin, doxycycline, and tigecycline may be useful additions to polymyxin B in the treatment of infections caused by highly resistant carbapenemaseproducing K. pneumoniae. Further studies are warranted to determine if these in vitro findings translate into clinical efficacy.
Signs and symptoms of atypical pneumonia include fever, shortness of breath, cough, and chest pain. During the coronavirus disease 2019 (COVID-19) pandemic, identifying other causes of febrile respiratory illness in patients who tested positive for COVID-19 has been very challenging. Concerns over infecting healthcare personnel and other patients can impede further evaluations like bronchial lavage, lung biopsies, and other invasive tests. A very high index of suspicion, perhaps unreasonably so, is required to perform invasive tests to investigate alternative possible causes of the illness. We present the case of a 63-yearold man who presented to the hospital with dyspnea. Chest X-ray demonstrated a consolidation in the left lower lobe lung field with a possible underlying mass, and the patient tested positive for COVID-19. He received the standard treatment for COVID pneumonia at the time in our institution (remdesivir and dexamethasone), empiric antibiotics for community-acquired pneumonia, and was eventually discharged home with supplemental oxygen. Several days later, the patient returned to the hospital again with worsening dyspnea and was readmitted. Persistent illness and worsening imaging prompted bronchoscopy. The bronchoscopy showed narrowing of the airway in the left upper lobe, and Nocardia asteroides was isolated from bronchial aspirate. The isolation of Nocardia prompted an investigation for central nervous system involvement with an magnetic resonance imaging (MRI) of the head. The MRI demonstrated multiple bilateral ring-enhancing lesions in the brain. To our knowledge, this is the first reported case of disseminated nocardiosis superimposed on COVID-19 pneumonia.
Myositis is a complication of many infectious and noninfectious processes. Secondary syphilis is an uncommon cause of myositis, and, therefore, the diagnosis may be delayed. We describe a man with human immunodeficiency virus infection presenting with diffuse muscle injury secondary to syphilis. He had complete resolution of all signs and symptoms after treatment with intravenous penicillin.
We discuss a case report of a 38-year-old uncircumcised male on pre-exposure prophylaxis for human immunodeficiency virus who presents to the emergency department for painful lesions over his penile region following unprotected sexual intercourse. Following the development of these lesions he developed painless, itchy pustules over his bilateral arms and back. He also had extensive pain and swelling over his penile region, which prevented him from unretracting his foreskin. Chlamydia trachomatis, Herpes simplex virus, Neisseria gonorrhoeae, and syphilis tests were negative. He was positive for orthopoxvirus using polymerase chain reaction. A diagnosis of paraphimosis as a complication of monkeypox infection was made.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.