Sepsis overview
Synonyms and keywords: sepsis syndrome; septic shock; septicemia

# Overview
Sepsis is a condition characterized by a whole-body inflammatory state caused by infection. Septic shock is a serious medical condition caused by decreased tissue perfusion and oxygen delivery as a result of infection and sepsis.  It can cause multiple organ failure and death. Its most common victims are children, immunocompromised individuals, and the elderly. This is because their immune systems cannot cope with the infection as well as those of full-grown adults.

# Pathophysiology
The immunological response that causes sepsis is a systemic inflammatory response causing widespread activation of inflammation and coagulation pathways. This may progress to dysfunction of the circulatory system and, even under optimal treatment, may result in the multiple organ dysfunction syndrome and eventually death. A subclass of distributive shock, shock refers specifically to decreased tissue perfusion resulting in end-organ dysfunction. Cytokines TNF, IL-1, interferon , IL-6 released in a large scale inflammatory response results in massive vasodilation, increased capillary permeability, decreased systemic vascular resistance, and hypotension.  Hypotension reduces tissue perfusion pressure and thus tissue hypoxia ensues.  Finally, in an attempt to offset decreased blood pressure, ventricular dilatation and myocardial dysfunction will occur.

# Classification
In rough order of severity, these are bacteremia or fungemia; septicemia; sepsis, severe sepsis or sepsis syndrome; septic shock; refractory septic shock; multiple organ dysfunction syndrome, and death.

# Causes
The process of infection by bacteria or fungi can result in systemic signs and symptoms that are variously described. The condition develops as a response to certain microbial molecules which trigger the production and release of cellular mediators, such as tumor necrosis factors (TNF); these act to stimulate immune response.

# Differentiating Sepsis from other Diseases
Sepsis must be differentiated from other syndromes presnting with fever, hypotension such as the acute bacterial endocarditis, myocardial ring abscess, subacute bacterial endocarditis and bacterial meningitis.

# Epidemiology and Demographics
The hospitalization rate of those with a principal diagnosis of septicemia or sepsis more than doubled from 2000 through 2008. During the same period, the hospitalization rate for those with septicemia or sepsis as a principal or as a secondary diagnosis increased by 70% from 221 to 377 for every 100,000 people. Reasons for these increases may include an aging population with more chronic illnesses, greater use of invasive procedures, immunosuppressive drugs, chemotherapy, transplantation, and increasing microbial resistance to antibiotics.

# Risk Factors
Factors responsible for increased risk of sepsis may include an aging population with more chronic illnesses; greater use of invasive procedures, immunosuppressive drugs, chemotherapy, and transplantation; and increasing microbial resistance to antibiotics. Other patients population at increased risk are ICU admits, immunocompromised, bacteremic, with community acquired pneumonia, and with genetic predisposition.

# Natural History, Complications and Prognosis
There are many complications associated with sepsis, especially because it is a systemic phenomenon. Sepsis is a severe condition, and the prognosis of the patient will depend greatly on the condition and overall health of the patient. Many factors, such as age, hosts immune response, site of infection, type of infection, appropriate antibiotic therapy, and restoration of circulation of perfusion contribute to the overall prognosis.

# Diagnosis

## History and Symptoms
Symptoms of sepsis are often related to the underlying infectious process. When the infection crosses into the bloodstream the resulting symptoms of sepsis occur fever, chills, and rigors, confusion, anxiety, difficulty breathing, fatigue and malaise, nausea and vomiting.

## Physical Examination
The physical examination of sepsis shows findings of the causative system as well as some generalized features.

## Laboratory Findings
The international guideline committee for diagnosis of septic shock recommends obtaining appropriate cultures that may include at least two blood cultures, urine, cerebrospinal fluid, wounds, respiratory secretions, or other body fluid cultures before antimicrobial therapy is initiated. If such cultures do not cause significant delay in antibiotic administration, then other tests that may be done include blood gases, kidney function tests, platelet count, white blood cell count, blood differential, fibrin degradation products, and peripheral smear.

## Chest X Ray
There are no specific chest X-ray findings associated with sepsis but may show the features consistent with the primary source of infection.

## CT
There are no specific CT findings associated with sepsis but may show the features consistent with the primary source of infection.

## MRI
There are no specific MRI findings associated with sepsis but may show the features consistent with the primary source of infection.

## Echocardiography or Ultrasound
There are no specific echocardiography or ultrasound finidngs associated with sepsis but may show the features consistent with the primary source of infection.

# Treatment

## Medical Therapy
According to IDSA, "Surviving Sepsis Campaign" guidelines, the management protocol for sepsis include screening for high-risk patients; taking bacterial cultures soon after the patient arrived at the hospital; starting patients on broad-spectrum intravenous antibiotic therapy before the results of the cultures are obtained; identifying the source of infection and taking steps to control it (e.g., abscess drainage); administering intravenous fluids to correct a loss or decrease in blood volume; and maintaining glycemic (blood sugar) control.

## Surgery
Surgical intervention is not recommended for the management of sepsis

## Prevention
Prevent infections that can lead to sepsis by cleaning scrapes and wounds and getting regular vaccination against infections that cause sepsis can help in the prevention of sepsis.