Infections are among the most common diagnoses in the emergency department (ED), and antibiotics are among the most frequently prescribed drugs. Community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP) are frequently encountered in the ED, and pneumonia is the seventh leading cause of death in the United States. Cystitis, pyelonephritis, and complicated urinary tract infection (UTI) are often treated in the ED, with UTI being one of the most common reasons for healthy young women to require antimicrobial treatment. Intra-abdominal infections have an incidence of 3.5 million cases per year in the United States, and emergency clinicians must make complex decisions regarding appropriate evaluation and management. Skin and soft-tissue infections (SSTIs) are common, their incidence in the ED has been rising, and the emergence of methicillin-resistant Staphylococcus aureus (MRSA) infection has altered their management. Timely diagnosis and management of infectious disease, including proper antimicrobial treatment, is an important goal of emergency care. This issue of Emergency Medicine Practice reviews the available evidence and consensus guidelines for the management of common infectious diseases presenting to the ED and presents recommendations for treatment.
antibiotics, community-acquired, infectious, Methicillin-Resistant Staphylococcus Aureus, MRSA, community-acquired MRSA, CA-MRSA, pneumonia, community acquired pneumonia, CAP, antimicrobial, cystitis, pyelonephritis, urinary tract infection, infectious disease, skin infections, soft-tissue infections, practice guidelines, staphylococcal skin infections
At 7:00 on a Monday morning, the day begins with a full line-up of “to be seen.” A 35-year-old female with no past medical history presents to the ED complaining of cough and shortness of breath for 2 days that is progressively worsening. On physical examination, she is febrile with an oxygen saturation of 94% on room air and decreased breath sounds at the right base. You order a chest x-ray that shows right lower lobe consolidation.
The second patient on your tracking board is a 70-year-old female with fever, nausea, and back pain for 3 days. She is accompanied by her daughter, who states her mother hasn’t been herself today and that she had a similar presentation when she had a UTI 2 years ago. She is febrile to 38.3°C (101°F), oriented x2, with left costovertebral angle tenderness. Her urine dipstick is positive for leukocyte esterase and nitrites.
In the next bed, you are evaluating a 23-year-old male who has had a painful, swollen right forearm for 2 days. He reports a subjective fever earlier in the evening, but no other systemic symptoms. He denies any past medical history and has no IV drug abuse and no history of diabetes. He is afebrile with normal vital signs. A 6-cm area of erythema, induration, and tenderness is noted on his proximal forearm with a 2-cm central fluctuant, raised area. He has full range of motion at the elbow.
Just as you sit down for a cup of coffee, the triage nurse notifies you that she just received an 85-year-old male from a nursing home that was sent in for evaluation for fever. He has a history of insulin-dependent diabetes mellitus, hypertension, and dementia. On physical examination, he is febrile, with otherwise normal vital signs. His abdomen is slightly distended, soft, but diffusely tender to palpation.
Four infectious disease cases in a row — it feels like an epidemic. You reflect on the challenge of choosing the right antibiotic in the age of emerging pathogens and how the right choice may be the difference between a good or bad outcome.
Clinicians who treat infectious diseases in the ED need to apply a vast amount of knowledge regarding not only which antibiotics are appropriate in a particular situation, but also the relevant microbiology, diagnostic testing, and pathophysiology of the underlying disease. Timely diagnosis and management of infectious disease, including proper antimicrobial treatment in the ED, has been shown to decrease morbidity and mortality in bacterial meningitis and sepsis1 and should be a goal of emergency care. To facilitate proper broad-spectrum coverage for initial antibiotic administration while decreasing unnecessary antibiotic use and propagating the emerging problem of multidrug-resistant organisms, evidence-based guidelines have been developed by the Infectious Diseases Society of America (IDSA) in collaboration with multiple specialty societies.
Knowledge of these guidelines and proper empiric therapy is of utmost importance to the emergency clinician when treating common and uncommon infections. Familiarity with comorbidities and risk factors for multidrug-resistant organisms and complicated infections as well as clinical decision rules to help guide diagnostic modalities, surgical consultation, and admission criteria for intravenous (IV) antibiotics may also be helpful in ensuring patients receive the best chances for proper diagnosis and appropriate treatment. This issue of Emergency Medicine Practice focuses on common infectious diseases presenting to the ED and reviews the current literature and guidelines.
For this evidence-based review article, an extensive search of the PubMed database, Ovid MEDLINE®, and the Cochrane Database of Systematic Reviews was performed. A search for relevant guidelines was performed via the Agency for Healthcare Research and Quality National Guideline Clearinghouse. A thorough review of consensus guidelines and evaluation of their citations was undertaken. An online search of the IDSA website, the Centers for Disease and Control and Prevention (CDC) website, and the American College of Emergency Physicians (ACEP) website was performed.
Recommendations were formulated, to a large degree, from the available relevant guidelines of the IDSA. These include the joint recommendations for the management of pneumonia from the IDSA and the American Thoracic Society (ATS), the 2005 “Guidelines for the Management of Adults with Hospital-Acquired, Ventilator-Associated, and Healthcare-Associated Pneumonia,” and the 2007 “Community-Acquired Pneumonia in Adults: Guidelines for Management.” The authors also thoroughly reviewed the 2010 “Guidelines for the Selection of Anti-Infective Agents for Complicated Intra-Abdominal Infections,” “International Clinical Practice Guidelines for Antimicrobial Treatment of Acute Uncomplicated Cystitis and Pyelonephritis in Women,” the 2009 “Diagnosis, Prevention, and Treatment of Catheter-Associated Urinary Tract Infections in Adults,” and the 2005 Association of Medical Microbiology and Infectious Disease Canada Guidelines Committee’s “Complicated Urinary Tract Infection in Adults.” For skin infections, the 2005 “Practice Guidelines for the Diagnosis and Management of Skin and Soft-Tissue Infections” and the 2011 “Management of Patients with Infections Caused by Methicillin-Resistant Staphylococcus aureus: Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA)” were reviewed. Information for skin and soft-tissue infections was also obtained from the October 2010 Emergency Medicine Practice Issue, “Emergency Department Infections in the Era of CA-MRSA.”
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.
To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study, will be included in bold type following the reference, where available.
Denise Nassisi; Marisa L. Oishi
January 2, 2012