Difference Between Sepsis and Septic Shock

Main Difference – Sepsis vs Septic Shock

Sepsis and Septic shock are two infectious conditions of blood which are categorized depending on their severity. Even though the basic pathophysiology is similar to one another, there are many significant differences between them. The main difference between sepsis and septic shock is that sepsis (or septicemia) is a life-threatening condition that arises when the body’s response to infection injures its own tissues and organs whereas septic shock is the most severe stage of sepsis.  

This article covers, 

1. What is Sepsis?
– Condition, Causes and Risk Factors, Signs and Symptoms, Diagnosis and Treatment

2. What is Septic Shock?
– Condition, Cause, Signs and Symptoms, Diagnosis and Treatment

3. What is the difference between Sepsis and Septic Shock?Difference Between Sepsis and Septic Shock - Sepsis vs Septic Shock Comparison Summary

What is Sepsis

Sepsis, also known as septicemia or blood poisoning, is defined as a clinical syndrome associated with life-threatening dysfunction of organs that occurs as a result of an uncontrollable and exaggerated response of the body to an infection.

Pathogenic microorganisms that initially invade blood can progressively invade organs in the body, giving rise to various dysfunctions and impairments.

This is most likely to affect patients with chronic diabetes, chronic inflammatory conditions, and malignancies. Chemotherapy and extremities of age can also be risk factors.

Signs and Symptoms

Early signs and symptoms of sepsis are characterized by,

  • High fever with chills and rigors
  • Tachycardia (raced heart beat)
  • Tachypnea (rapid breathing)
  • Hypotension (significant drop in blood pressure)
  • Faintishness or dizziness
  • Confusion and disorientation
  • Nausea, vomiting, and diarrhea
  • Slurred speech
  • Severe breathlessness
  • Reduced urine output
  • Cold and clammy skin
  • Loss of consciousness

Diagnosis and Treatment

Early diagnosis of Sepsis is critical since it can result in organ failure which can possibly end in death.

The major method of diagnosis includes a positive history with suspected signs and symptoms (fever, tachycardia, tachypnea) along with a blood culture showing gram-positive or negative bacterial infection.

There are several other investigations which can be carried out; they are,

  • Complete blood count
  • Urine and stool culture
  • Wound culture
  • 24-hour blood pressure monitoring
  • Imaging studies- X-ray, CT scan, MRI scan

Accurately diagnosed Sepsis is treated with aggressive fluid replacement, antibiotics, surgical excision of infected wounds or necrosed tissues and drainage of pus. Furthermore, appropriate supportive care is highly recommended to increase the prognosis of the condition.

Sepsis, which is effectively treated before an irreversible organ failure takes place, will most probably achieve a complete recovery without any lasting complications within few days to weeks.

However, the nature of recovery and time duration will depend on the severity of sepsis, the overall health of individuals, time duration spent in the hospital and necessity of an ICU admission.

Difference Between Sepsis and Septic Shock - 1

What is Septic Shock

Septic shock is defined as ‘a subset of sepsis which is associated with a significant rate of mortality as a result of various fatal abnormalities of blood circulation and cellular metabolism’.

It often affects  neonates, elderly people and pregnant women, patients who are chronically suffering from diseases such as Diabetes Mellitus, Cirrhosis, Leukopenia and following cytotoxic drugs or invasive procedures (catheterization, IV tube insertion).

Although, a clear pathophysiology of septic shock has not been identified yet, a severe inflammatory response induced by various toxins released by pathogenic organisms is known to release pro-inflammatory positive mediators like TNF Alpha, IL-1, leukotrienes, lipoxygenase, bradykinin, serotonin and opposing factors like IL-4 and IL-10 which will trigger a negative feedback mechanism. These will eventually trigger a neutrophil–endothelial cell adhesion, clotting mechanism which will result in the formation of microthrombi.

As far as the etiology of septic shock is concerned, hospital-acquired gram-negative bacilli and gram-positive Cocci are the commonest pathogens whereas Candida and Fungi can rarely be identified in certain individuals with severe immune-suppression.

It is also important to look for any signs of a deep or superficial infection (Gastrointestinal, urinary or biliary tract) especially in patients who have recently undergone surgery.

Signs and Symptoms

Characteristic features of this condition include,

  • Persistent hypotension which requires vasopressors to maintain a mean arterial pressure ≥ 65 mm Hg
  • Serum lactate level > 18 mg/dL which do not improve on rapid fluid replacement.

Other signs and symptoms of septic shock are similar to those seen in patients with ‘Sepsis’ but mostly of a severe nature. However, the major sign which is observed when a patient develops shock from septicemia is rapid confusion and altered level of consciousness, which may sometimes end up in a coma.

Diagnosis and Treatment

Major investigations that should be carried out in a clinically suspected patient include Complete Blood Count, Arterial Blood Gases, chest x-ray, serum electrolytes, BUN and creatinine, liver function, Serum lactate levels and central venous O2 saturation (ScvO2).

Early treatment of septic shock is critical and mainly depends on the etiology and include supportive therapy and acute resuscitation based on the process of monitoring.

  • Blood Perfusion which is mainly restored with IV fluids and Vasopressors
  • Oxygen therapy
  • Broad-spectrum antibiotics
  • Controlling of the infection
  • Other supportive measures such as Corticosteroids, Insulin,

The overall mortality rate of patients with septic shock is gradually decreasing (30%-40%) thanks to the advancement of medical interventions lately, but patients who develop severe lactic acidosis with decompensated metabolic acidosis should be given early immediate care due to the high possibility of multi-organ failure which is fatal and irreversible.

Difference Between Sepsis and Septic Shock

Sepsis is a blood infection which is triggered by various microbial toxins released into the blood stream, triggering a systemic inflammatory response. This most often occurs as a complication of disease conditions such as pneumonia, food poisoning, urinary tract infections, etc. but doesn’t result in any organ failure.

In contrast, Septic shock is a subtype of sepsis, associated with a significant rate of mortality as a result of various fatal abnormalities of blood circulation and cellular metabolism, resulting in fatal and irreversible organ failure.

Untreated or delayed treatment of sepsis can result in Septic shock which should be tried at its best to be avoided since the prognosis is comparatively very poor.

Image Courtesy:

“Sepsis Steps” By Hadroncastle – Own work (CC BY-SA 4.0) via Commons Wikimedia

About the Author: Embogama

Embogama is a passionate freelance writer for several years. Her areas of interest include general medicine, clinical medicine, health and fitness, Ayurveda medicine, psychology, counseling and piano music