Practice EssentialsDefinitionsSepsis is a life-threatening syndrome usually caused by bacterial infection. Sepsis is a response of the body's immune system that results in organ dysfunction or failure. The systemic inflammatory response syndrome (SIRS) criteria were recently replaced by the quick Sequential Organ Failure Assessment (qSOFA) in 2016, allowing for quick bedside analysis of organ dysfunction in patients with suspected or documented infection. The qSOFA score includes a respiratory rate of 22 breaths/minute or more, systolic blood pressure of 100 mm Hg or less, and altered level of consciousness. [1, 2] For completeness, severe sepsis is defined as sepsis complicated by organ dysfunction. Show
Multiple organ dysfunction syndrome (MODS) is characterized by progressive organ dysfunction in a severely ill patient, with failure to maintain homeostasis without intervention. It is the end stage in infectious conditions (sepsis, septic shock) and noninfectious conditions (eg, SIRS due to pancreatitis). The greater the number of organ failures, the higher the mortality risk, with the greatest risk associated with respiratory failure requiring mechanical ventilation. MODS can be classified as primary or secondary. [3] Primary MODS is the direct result of identifiable injury or insult with early organ dysfunction (eg, renal failure due to a nephrotoxic agent or liver failure due to a hepatotoxic agent). Secondary MODS is organ failure that has no attributable cause and is a consequence of the host's response (eg, acute respiratory distress syndrome [ARDS] in individuals with pancreatitis). The following parameters are used to assess individual organ dysfunction:
Septic shock is defined as sepsis with hypotension requiring vasopressor therapy to maintain a mean blood pressure of more than 65 mm Hg and a serum lactate level exceeding 2 mmol/L (18 mg/dL) after adequate fluid resuscitation. [1] This has a greater risk of mortality and long-term morbidity. Pseudosepsis is defined as fever, leukocytosis, and hypotension due to causes other than sepsis. Examples might include the clinical picture seen with salicylate intoxication, methamphetamine overdose, or bilateral adrenal hemorrhage. EtiologySepsis can be caused by an obvious injury or infection or a more complicated etiology such as perforation, compromise, or rupture of an intra-abdominal or pelvic structure. [4] Other etiologies can include meningitis, head and neck infections, deep neck space infections, pyelonephritis, renal abscess (intrarenal or extrarenal), acute prostatitis/prostatic abscess, severe skin or skin structure infections (eg, necrotizing fasciitis), postsurgical infections, or systemic infections such as rickettsial infection. A more detailed discussion of sepsis etiology in various organ systems is provided in Etiology. Clinical PresentationIndividuals with sepsis may present with localizing symptoms related to a specific site or source of infection or may present with nonspecific symptoms. Individuals with nonspecific symptoms are usually acutely ill with fever and may present with or without shaking chills. Mental status may be impaired in the setting of fever or hypotension. Patients with bacteremia from any source often display an increased breathing rate resulting in respiratory alkalosis. The skin of patients with sepsis may be warm or cold, depending on the adequacy of organ and skin perfusion. A detailed history and physical examination is essential in determining the likely source of the septic process (See History and Physical Examination). This helps the clinician to determine the appropriate treatment and antimicrobial therapy (see Treatment for further detail). See Clinical Presentation for more detail. DiagnosisA diagnosis of sepsis is based on a detailed history, physical examination, laboratory and microbiology testing, and imaging studies. Laboratory studies that may be considered include the following:
Imaging modalities should be focused on areas of clinical concern, based on the history and physical examination, and may include the following:
The following cardiac studies may be useful if cardiac involvement or disease is suspected as a cause or complication of infection:
Invasive diagnostic procedures that may be considered include the following:
See Workup for more detail. ManagementInitial management may include the following:
Appropriate empiric antimicrobial therapy depends on adequate coverage of the presumed pathogen(s) responsible for the septic process, potential antimicrobial resistance patterns, and patient-specific issues such as drug allergies or chronic medical conditions. Tying sites of infection to specific pathogens should occur, as follows:
Early surgical evaluation for presumed intra-abdominal or pelvic sepsis is essential. Procedures that may be warranted depend on the source of the infection, the severity of sepsis, and the patient’s clinical status, among other factors. Once an etiologic pathogen is identified, typically via culture, narrowed antibiotic therapy against the identified pathogen is appropriate (eg, penicillin for penicillin-susceptible Streptococcus pneumoniae). See Treatment and Medication for more detail. BackgroundHippocrates, in the fourth century BCE, used the term sepsis denoting decomposition. Avicenna, in the eleventh century, called diseases causing purulence as blood rot. In the nineteenth century, the term sepsis was widely used to describe severe systemic toxicity. A closely derived term of septicemia was used for bacterial infection in the blood, which has been replaced by the term bacteremia. In the last two centuries, the processes underlying infections have been better studied and elucidated. The role of microorganisms in causing infections and the intricate mechanisms of various intrinsic and extrinsic toxins in damaging body tissues that result in fever and shock has been discovered with painstaking research. At the beginning of the twentieth century, the term endotoxin was devised by Pfeiffer to explain the causative agent in infection with cholera. It was later linked to other gram-negative bacterial pathogenicity. [9] The initial sepsis guidelines were published in 2004 and revised in 2008 and 2012. The current clinical practice guidelines are a revision of the 2012 Surviving Sepsis Campaign (SSC) guidelines for the management of severe sepsis and septic shock. (See Guidelines.) EtiologyThe etiology of sepsis is diverse, and clinical clues to various organ systems aid in appropriate workup and diagnosis. It is also pertinent to be able to distinguish between the infectious and noninfectious causes of fever in a septic patient. The following are organ system–specific etiologies of possible sepsis:
There are numerous noninfectious causes of fever and organ dysfunction that can mimic sepsis: [11]
Table 1. Infectious and Noninfectious Causes of Fever [12] (Open Table in a new window)
An abdominal wall abscess is depicted on the CT scan below. A right lower quadrant abdominal wall abscess and enteric fistula are observed and confirmed by the presence of enteral contrast in the abdominal wall.Organisms can be introduced via various mechanisms, including direct inoculation of microbes into the body or body site, such as in skin or soft tissue infections or bloodstream infections associated with indwelling venous catheters. Inhalational acquisition is a mode of infection in the setting of respiratory infection, as is aspiration of oral/gastric content. Ascending urinary tract infection can also cause systemic infection. The gastrointestinal tract can also be a source of infection if contents macroscopically rupture or seed the intra-abdominal compartment or if organisms translocate through the mucosal barrier. Other mucosal surfaces can also serve as entry points, including the conjunctiva, the upper respiratory tract, and the genitourinary tract. External disease-transmitting vectors, such as arthropods, can also cause infection. [4, 13] The pathophysiology of sepsis is complex and results from the effects of circulating bacterial products, mediated by cytokine release, caused by sustained bacteremia. Cytokines are responsible for the clinically observable effects of bacteremia in the host. [13, 14, 15, 16] Impaired pulmonary, hepatic, or renal function may result from excessive cytokine release during the septic process. PrognosisSepsis is a common cause of mortality and morbidity worldwide. The prognosis depends on underlying health status and host defenses, prompt and adequate surgical drainage of abscesses, relief of any obstruction of the intestinal or urinary tract, and appropriate and early empiric antimicrobial therapy. [17] The prognosis of sepsis treated in a timely manner and with appropriate therapy is usually good, except in those with intra-abdominal or pelvic abscesses due to organ perforation. When timely and appropriate therapy has been delivered, the underlying physiologic condition of the patient determines outcome. A systematic review by Winters et al suggested that beyond the standard 28-day in-hospital mortality endpoint, ongoing mortality in patients with sepsis remains elevated up to 2 years and beyond. [18] In addition, survivors consistently demonstrate impaired quality of life. [19] Clinical characteristics that affect the severity of sepsis and, therefore, the outcome include the host's response to infection, the site and type of infection, and the timing and type of antimicrobial therapy. Host-related Abnormal host immune responses may increase susceptibility to severe disease and mortality. For example, extremes of temperature and the presence of leukopenia and/or thrombocytopenia, advanced age, presence of co-morbid conditions, hyperglycemia, bleeding diatheses, and failure of procalcitonin levels to fall have all been associated with worsened outcome. [20] Important risk factors for mortality include the patient's comorbidities, functional health status, newly onset atrial fibrillation, hypercoagulability state, hyperglycemia on admission, AIDS, liver disease, cancer, alcohol dependence, and immune suppression. Age older than 40 years is associated with comorbid illnesses, impaired immunologic responses, malnutrition, increased exposure to potentially resistant pathogens in nursing homes, and increased use of medical devices, such as indwelling catheters and central venous lines. [21, 22, 23, 24] Infection site Sepsis due to urinary tract infection has the lowest mortality rate, while mortality rates are higher with unknown sources of infection, gastrointestinal sources (highest in ischemic bowel), and pulmonary sources. [25, 26, 27] Infection type Sepsis due to nosocomial pathogens has a higher mortality rate than sepsis due to community-acquired pathogens. Increased mortality is associated with bloodstream infections due to Staphylococcus aureus, fungi, and Pseudomonas, as well as polymicrobial infections. When bloodstream infections become severe (ie, septic shock), the outcome may be similar regardless of whether the pathogenic bacteria are gram-negative or gram-positive. Antimicrobial therapy Studies have shown that the early administration of appropriate antibiotic therapy (ie, antibiotics to which the pathogen is sensitive) is beneficial in septic patients demonstrating bacteremia. Previous antibiotic therapy (ie, antibiotics within the prior 90 days) may be associated with increased mortality risk, at least among patients with gram-negative sepsis. Patients who have received prior antibiotic therapy are more likely to have higher rates of antibiotic resistance, reducing the likelihood that appropriate antibiotic therapy will be chosen empirically. [28, 29, 30, 31] Restoration of perfusion Failure to attempt aggressive restoration of perfusion early may also be associated with an increased mortality risk. A severely elevated lactate level (>4 mmol/L) is associated with a poor prognosis in patients with sepsis. EpidemiologyIncidence The incidence of sepsis and the number of sepsis-related deaths are increasing because of an increased use of immunosuppressive medications. The incidence varies by race and sex. The highest incidence is among black males. The incidence also shows seasonal variation, with the highest number of cases in winter, probably because of the increased prevalence of respiratory infections during this season. Older patients (≥65 years) account for most (60%-85%) sepsis cases, attributable to multiple comorbidities and frequent hospitalizations. [17] Pathogens The predominant infectious organisms that cause sepsis have changed over the years. Gram-positive bacteria are the most common etiologic pathogens, although the incidence of gram-negative sepsis remains substantial. The incidence of fungal sepsis has been rising with more patients on immunosuppressive therapies and more cases of HIV infection. In approximately half of sepsis cases, the organism is not identified (culture-negative sepsis). Risk FactorsRisk factors for sepsis and septic shock include the following:
Author Coauthor(s) Nirav Patel, MD † Assistant Professor of Internal Medicine, Division of Infectious Diseases, Allergy and Immunology, and Division of Pulmonary, Critical Care, and Sleep Medicine, St Louis University School of Medicine; Chief Medical Officer, Director of Antibiotic Stewardship, Infection Control Officer, St Louis University Hospital Nirav Patel, MD is a member of the following medical societies: American Medical Association, Infectious Diseases Society of America, Infectious Diseases Society of St Louis, Missouri State Medical Association, Society for Healthcare Epidemiology of America Disclosure: Nothing to disclose. Specialty Editor Board Chief Editor Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America; Fellow of the Royal College of Physicians, London Michael Stuart Bronze, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Medical Association, Association of Professors of Medicine, Infectious Diseases Society of America, Oklahoma State Medical Association, Southern Society for Clinical Investigation Disclosure: Nothing to disclose. Additional Contributors Acknowledgements Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Department of Internal Medicine, Director of Infectious Disease Fellowship, Harper Hospital, Wayne State University School of Medicine Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians and Infectious Diseases Society of America Disclosure: Nothing to disclose. Thomas M Kerkering, MD Chief of Infectious Diseases, Virginia Tech Carilion School of Medicine Thomas M Kerkering, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Public Health Association, American Society for Microbiology, American Society of Tropical Medicine and Hygiene, Infectious Diseases Society of America, Medical Society of Virginia, and Wilderness Medical Society Disclosure: Nothing to disclose. Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference Disclosure: Medscape Salary Employment Which of the following skin lesions are usually caused by staphylococcus?Staphylococcus aureus (S. aureus or “staph”) is the leading cause of skin and soft tissue infections such as abscesses (boils), furuncles, and cellulitis.
What diseases cause skin problems?Skin Diseases. Acne. What is acne? ... . Alopecia Areata. What is alopecia areata? ... . Atopic Dermatitis. What is atopic dermatitis? ... . Epidermolysis Bullosa. What is epidermolysis bullosa? ... . Hidradenitis Suppurativa (HS) ... . Ichthyosis. ... . Pachyonychia Congenita. ... . Pemphigus.. What is the best medicine for skin infection?Antibiotics: Oral antibiotics are used to treat many skin conditions. Common antibiotics include dicloxacillin, erythromycin, and tetracycline. Antifungal agents: Oral antifungal drugs include fluconazole and itraconazole. These drugs can be used to treat more severe fungal infections.
Which fungal infection manifests on the surface of a patient's skin with an erythematous and typically annular?Subacute cutaneous lupus erythematosus (SCLE) – SCLE is a subtype of cutaneous lupus erythematous that can manifest as annular or polycyclic, scaly plaques on sun-exposed skin (picture 26).
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