Why would all parameters be below normal during an infection?

From the Guidelines

During an infection, all vital signs and laboratory values may be below normal due to the body's response to the pathogen, and this pattern often indicates a serious infection requiring prompt medical attention. When the immune system fights an infection, it can cause a decrease in various parameters.

• White blood cell count may decrease (leukopenia) as these cells are consumed in the battle against pathogens.
• Platelet counts may drop (thrombocytopenia) due to increased consumption or decreased production.
• Blood pressure often falls (hypotension) due to vasodilation and increased vascular permeability caused by inflammatory mediators, as seen in sepsis and septic shock 1.
• Body temperature might be below normal (hypothermia) in severe infections, particularly in elderly patients or those with compromised immune systems.
• Blood glucose levels can decrease (hypoglycemia) as the body's metabolic demands increase while fighting infection.
• Oxygen saturation may drop due to respiratory compromise. These decreases occur because the infection triggers systemic inflammatory responses that alter normal physiological functions, redirecting resources to fight the pathogen while potentially compromising other bodily systems.
• The use of antimicrobials, such as aminoglycosides, fluoroquinolones, vancomycin, and β-lactams, is crucial in treating infections, and their dosing strategies should be optimized to achieve the best possible outcomes, as recommended by the Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock: 2016 1.
• Early attention to appropriate antimicrobial dosing is central to improving outcomes, given the marked increase in mortality and other adverse outcomes if there is a failure of rapid initiation of effective therapy 1.

From the Research

Coagulation and Infection

• During infection, coagulation can be activated, leading to the formation of blood clots [ 2 ].
• This activation of coagulation is a fundamental host response against infection, but it can also produce injury to the host [ 2 ].
• Disseminated intravascular coagulation (DIC) is a common complication of sepsis, and its early recognition and management are crucial [ 2 ].

Sepsis and Disseminated Intravascular Coagulation

• Sepsis can lead to DIC, which is characterized by thrombosis in the microvasculature [ 3 ].
• DIC can result in organ dysfunction and is a strong prognostic factor for poor outcomes [ 4 ].
• The diagnosis of DIC is based on coagulation test results and clinical setting, and it should be distinguished from other similar conditions [ 2 ].

Pathophysiology of Sepsis-Induced DIC

• The pathophysiology of sepsis-induced DIC involves the activation of coagulation, inflammation, and other pathways [ 2 ].
• The activation of coagulation can lead to the formation of blood clots, which can cause organ dysfunction [ 4 ].
• The inhibition of fibrinolysis and the consumption of blood thinners can also contribute to the development of DIC [ 4 ].

Treatment of Sepsis-Induced DIC

• The treatment of sepsis-induced DIC involves the management of the underlying infection and the use of adjunct therapies such as antithrombin, thrombomodulin, and heparins [ 2 ].
• Other treatments, such as corticosteroids, recombinant thrombomodulin, and vitamin C, may also be effective in managing sepsis-induced DIC [ 4 ].
• Immunomodulatory therapy, such as granulocyte colony-stimulating factor and mesenchymal stem cell therapy, may also have a role in the treatment of sepsis-induced DIC [ 4 ].