F e v e r i n I m m u n o c o m p ro m i s e d Hosts Devang M. Patel,
MD*,
David J. Riedel,
MD
KEYWORDS Fever HIV AIDS Neutropenic fever Solid-organ transplant Tumor necrosis factor-a inhibitors Hematopoietic stem cell transplant Emergency department KEY POINTS A thorough history and physical examination are necessary to determine the type and severity of immunosuppression and elucidate patients’ history of exposures to specific pathogens. Immunosuppressed patients are at risk for infections from many pathogens, including organisms commonly seen in normal hosts as well as rare and atypical organisms. Obtaining an early blood culture, before the introduction of antimicrobials, is critical to establishing a diagnosis in many patients. Prompt, empiric antimicrobial coverage should be given to patients at highest risk of systemic infection and to those showing signs or symptoms of clinical deterioration. Antimicrobial use in patients who are not systemically ill should be judicious so as not to compromise diagnostic procedures. Invasive diagnostic procedures might be required to establish the diagnosis.
Emergency department (ED) health care providers continue to see increasing numbers of immunocompromised patients; in many of these individuals, the immunocompromised state has an iatrogenic cause.1,2 Since the 1980s, the human immunodeficiency virus (HIV) epidemic created one of the most important populations of immunocompromised hosts ever seen by physicians. The presentation of these patients has changed in the era of combined antiretroviral therapy (cART).3,4 In addition, medicine has seen an increase in the number of solid-organ and hematologic transplantations, the use of chemotherapeutic agents for the treatment of malignancies, and the
Devang M. Patel and David J. Riedel contributed equally to this work. Disclosure: The authors declare no conflicts of interest. Division of Infectious Disease, Department of Medicine, Institute of Human Virology, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, MD 21201, USA * Corresponding author. Division of Infectious Diseases, Institute of Human Virology, University of Maryland School of Medicine, 725 West Lombard Street, N559, Baltimore, MD 21201. E-mail address: [email protected] Emerg Med Clin N Am 31 (2013) 1059–1071 http://dx.doi.org/10.1016/j.emc.2013.07.002 0733-8627/13/$ – see front matter Ó 2013 Elsevier Inc. All rights reserved.
emed.theclinics.com
1060
Patel & Riedel
administration of monoclonal antibodies for many autoimmune diseases, leading to an increase in the number of immunocompromised individuals living in communities. When assessing immunocompromised patients, one of the most important first steps is to determine the type of immunosuppression the patients are experiencing. The type dictates what aspect of the immune system is affected, which in turn determines the types of pathogens most likely to cause disease in those patients. Some patients presenting to the ED with fever represent true emergencies (eg, neutropenic fever in patients with cancer) and must be treated empirically with antimicrobials immediately to avoid life-threatening complications. In most immunosuppressed patients, a fever represents a diagnostic dilemma requiring consultation by infectious diseases specialists and, in many cases, invasive diagnostic procedures to identify the infective organism. In the ED, empiric administration of antimicrobials should be used judiciously to treat the most likely infections suggested by the patients’ clinical presentation. Overuse of antimicrobials can lead to unwanted side effects, drugdrug interactions, and difficulty in establishing a definitive diagnosis. This review focuses on the common febrile syndromes associated with the different types of immunosuppression and their importance in the ED setting. HIV/AIDS
Most clinicians are aware of the decline in cell-mediated immunity that occurs during infection with HIV and leads to AIDS.5 Just as important is the dysfunction in humoral immunity that predisposes patients to recurrent bacterial infections.6 Over time, this immunosuppression puts patients at risk for opportunistic infections (OIs) (Table 1). In the era of cART, the number of hospitalizations for OIs has declined substantially, but infections (particularly bacterial pneumonia and cellulitis) are still the primary reason for the hospitalization of patients infected with HIV.3,4 Rather than discuss the wide array of OIs described in the literature, the focus here is on the more common infections that ED health care providers are likely to encounter while caring for patients with HIV. PULMONARY SYNDROMES
In the cART era, pulmonary syndromes, including chronic obstructive pulmonary disease and asthma, remain the top reason for hospitalization among patients with HIV.4 Patients with pulmonary syndromes are at an increased risk of bacterial pneumonias Table 1 Primary prophylaxis in patients with HIV Opportunistic Infection
Indications
Drug of Choice
Pneumocystis pneumonia
CD4 count
MD*,
David J. Riedel,
MD
KEYWORDS Fever HIV AIDS Neutropenic fever Solid-organ transplant Tumor necrosis factor-a inhibitors Hematopoietic stem cell transplant Emergency department KEY POINTS A thorough history and physical examination are necessary to determine the type and severity of immunosuppression and elucidate patients’ history of exposures to specific pathogens. Immunosuppressed patients are at risk for infections from many pathogens, including organisms commonly seen in normal hosts as well as rare and atypical organisms. Obtaining an early blood culture, before the introduction of antimicrobials, is critical to establishing a diagnosis in many patients. Prompt, empiric antimicrobial coverage should be given to patients at highest risk of systemic infection and to those showing signs or symptoms of clinical deterioration. Antimicrobial use in patients who are not systemically ill should be judicious so as not to compromise diagnostic procedures. Invasive diagnostic procedures might be required to establish the diagnosis.
Emergency department (ED) health care providers continue to see increasing numbers of immunocompromised patients; in many of these individuals, the immunocompromised state has an iatrogenic cause.1,2 Since the 1980s, the human immunodeficiency virus (HIV) epidemic created one of the most important populations of immunocompromised hosts ever seen by physicians. The presentation of these patients has changed in the era of combined antiretroviral therapy (cART).3,4 In addition, medicine has seen an increase in the number of solid-organ and hematologic transplantations, the use of chemotherapeutic agents for the treatment of malignancies, and the
Devang M. Patel and David J. Riedel contributed equally to this work. Disclosure: The authors declare no conflicts of interest. Division of Infectious Disease, Department of Medicine, Institute of Human Virology, University of Maryland School of Medicine, 725 West Lombard Street, Baltimore, MD 21201, USA * Corresponding author. Division of Infectious Diseases, Institute of Human Virology, University of Maryland School of Medicine, 725 West Lombard Street, N559, Baltimore, MD 21201. E-mail address: [email protected] Emerg Med Clin N Am 31 (2013) 1059–1071 http://dx.doi.org/10.1016/j.emc.2013.07.002 0733-8627/13/$ – see front matter Ó 2013 Elsevier Inc. All rights reserved.
emed.theclinics.com
1060
Patel & Riedel
administration of monoclonal antibodies for many autoimmune diseases, leading to an increase in the number of immunocompromised individuals living in communities. When assessing immunocompromised patients, one of the most important first steps is to determine the type of immunosuppression the patients are experiencing. The type dictates what aspect of the immune system is affected, which in turn determines the types of pathogens most likely to cause disease in those patients. Some patients presenting to the ED with fever represent true emergencies (eg, neutropenic fever in patients with cancer) and must be treated empirically with antimicrobials immediately to avoid life-threatening complications. In most immunosuppressed patients, a fever represents a diagnostic dilemma requiring consultation by infectious diseases specialists and, in many cases, invasive diagnostic procedures to identify the infective organism. In the ED, empiric administration of antimicrobials should be used judiciously to treat the most likely infections suggested by the patients’ clinical presentation. Overuse of antimicrobials can lead to unwanted side effects, drugdrug interactions, and difficulty in establishing a definitive diagnosis. This review focuses on the common febrile syndromes associated with the different types of immunosuppression and their importance in the ED setting. HIV/AIDS
Most clinicians are aware of the decline in cell-mediated immunity that occurs during infection with HIV and leads to AIDS.5 Just as important is the dysfunction in humoral immunity that predisposes patients to recurrent bacterial infections.6 Over time, this immunosuppression puts patients at risk for opportunistic infections (OIs) (Table 1). In the era of cART, the number of hospitalizations for OIs has declined substantially, but infections (particularly bacterial pneumonia and cellulitis) are still the primary reason for the hospitalization of patients infected with HIV.3,4 Rather than discuss the wide array of OIs described in the literature, the focus here is on the more common infections that ED health care providers are likely to encounter while caring for patients with HIV. PULMONARY SYNDROMES
In the cART era, pulmonary syndromes, including chronic obstructive pulmonary disease and asthma, remain the top reason for hospitalization among patients with HIV.4 Patients with pulmonary syndromes are at an increased risk of bacterial pneumonias Table 1 Primary prophylaxis in patients with HIV Opportunistic Infection
Indications
Drug of Choice
Pneumocystis pneumonia
CD4 count
