How to treat typhoid fever? What is the cause of the disease?

In our daily life, we must exercise regularly and understand some basic knowledge about diseases, which will help us prevent and treat diseases as early as possible. So what is typhoid fever? What is the cause of the disease?

Introduction

Typhoid fever is an acute gastrointestinal infectious disease caused by Salmonella typhi. The main pathological changes are proliferative reactions of the systemic mononuclear macrophage system, with hyperplasia and necrosis of lymphoid tissue in the lower ileum as the main lesions. Typical cases are characterized by persistent fever, relatively slow pulse, apathy, splenomegaly, roseola and leukopenia. The main complications are intestinal bleeding and intestinal perforation.

Disease classification

Typhoid fever is mainly divided into: common type, mild type, fulminant type, protracted type, free-flowing type, and abortive type.

Causes

Whether or not the disease develops after infection with Salmonella typhi is related to factors such as the number of bacteria, virulence, and the body's immunity. Factors such as low stomach acid, severe malnutrition, anemia, hypoproteinemia, etc. are also factors that cause typhoid fever.

Pathogenesis

Typhoid bacilli enter the stomach through the mouth. If they are not killed by stomach acid, they enter the small intestine, invade the collecting lymph nodes, isolated lymph follicles and mesenteric lymph nodes through the intestinal mucosa, multiply, and then enter the bloodstream through the portal vein or thoracic duct, forming the first bacteremia. If the body's immunity is weak, the bacteria will spread through the bloodstream to tissues such as the bone marrow, liver, spleen, and lymph nodes and multiply in large numbers. At the end of the incubation period, they will invade the bloodstream again in large numbers, forming a second bacteremia, and clinical manifestations such as fever, rash, and hepatosplenomegaly will begin to appear. At the same time, bacteria can spread through the blood circulation to various organs and tissues throughout the body and cause lesions, such as acute suppurative osteomyelitis, renal abscess, meningitis, acute cholecystitis, pericarditis, etc. The bacteria can enter the intestines through the bile duct and be excreted with feces, or be excreted through the kidneys with urine. The persistent fever of typhoid fever is caused by Salmonella typhi and its endotoxin. During the 2nd to 3rd week of the disease, some of the typhoid Salmonella that entered the intestine through the bile duct invaded the intestinal wall lymphoid tissue again, causing a severe inflammatory reaction in the already sensitized intestinal wall lymphoid tissue, causing swelling, necrosis, ulcers, etc. If the lesion affects the blood vessels, it may cause bleeding. If the ulcer reaches deep into the serosa, it may cause intestinal perforation. During the 4th to 5th week of the disease, the human body's immunity is enhanced, the typhoid Salmonella is gradually eliminated from the body, and the tissues are repaired and the disease is cured. However, about 3% of patients may become chronic carriers, and a small number of patients may relapse due to insufficient immune function and other reasons.