Thus, negative cognitions can cause inflammation that can, in turn, lead to depression. In addition, there is increasing evidence that inflammation can cause depression because of the increase of cytokines, setting the brain into a "sickness mode". Classical symptoms of being physically sick, such as lethargy, show a large overlap in behaviors that characterize depression. Levels of cytokines tend to increase sharply during the depressive episodes of people with bipolar disorder and drop off during remission. Furthermore, it has been shown in clinical trials that anti-inflammatory medicines taken in addition to antidepressants not only significantly improves symptoms but also increases the proportion of subjects positively responding to treatment. Inflammations that lead to serious depression could be caused by common infections such as those caused by a virus, bacteria or even parasites. Connection to delirium
There is evidence for a link between inflammation and delirium based on the results of a recent longitudinal study investigating CRP in COVID-19 patients. Systemic effects
An infectious organism can escape the confines of the immediate tissue via the circulatory system or lymphatic system, where it may spread to other parts of the body. If an organism is not contained by the actions of acute inflammation, it may gain access to the lymphatic system via nearby lymph vessels. An infection of the lymph vessels is known as lymphangitis, and infection of a lymph node is known as lymphadenitis. When lymph nodes cannot destroy all pathogens, the infection spreads further. A pathogen can gain access to the bloodstream through lymphatic drainage into the circulatory system.
black widow spider)
Malingering
Pneumoperitoneum secondary to abdominal trauma
Septic miscarriage (See Miscarriage)

Laboratory findings
Complete blood count (CBC)
Blood urea nitrogen (BUN)/creatinine
Liver function tests (LFTs)
Glucose
Amylase/lipase
Urine culture
Urinalysis
Beta-human chorionic gonadotropin (beta-hCG)
Cervical cultures are recommended to diagnose pelvic inflammatory disease

Electrolyte and biomarker studies
Electrolytes

MRI and CT
CT diagnoses:
Organ contusion
Organ laceration
Aneurysm
Diverticulitis
Appendicitis

Echocardiography or ultrasound
Pelvic, abdominal and/or transvaginal ultrasound diagnoses:
Peritonitis
Ectopic pregnancy
Ovarian cysts
Fluid/blood secondary to trauma
Appendicitis
Aneurysm

Other imaging findings
KUB x-ray imaging (kidney, ureter, bladder) could reveal nephrolithiasis and bowel gas pattern

Other diagnostic studies
Symptomatic relief may be provided by paracentesis, which may also diagnose spontaneous bacterial peritonitis (SBP)
Gastrointestinal endoscopy may be used or patients with suspected peptic ulcer disease
Helicobacter pylori testing may also be used
Trial medications may be beneficial for the diagnosis and treatment of:
GERD/dyspepsia: Proton pump inhibitors or H2 blockers
Abdominal wall strain: Nonsteriodal anti-inflammatory drugs (NSAIDs)
Anxiety: Lorazepam
Zoster: Acyclovir

Treatment
Specific conditions need direct treatment
Hemodynamic status and life-threatening disease require immediate attention
Volume replacement with a possible blood transfusion, and with normal saline
For obstruction and persistent vomiting, place nasogastric (NG) tube

Pharmacotherapy
If perforated viscus or intra-abdominal infection suspected, administer broad-spectrum empiric antibiotics

Surgery and device-based therapy
Early sepsis, or evidence of hemorrhage may require surgery (likely to be life-threatening emergency)

References
Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3