carcinoid syndrome
Introduction
Introduction A syndrome caused by paroxysmal skin flushing and diarrhea as a major clinical manifestation of carcinoid (syelophilic cell tumor) in the gastrointestinal tract. This tumor was mistaken for benign tumors in the past. It has been confirmed to be a malignant tumor, but it is slow to grow. The course of the disease is usually 10 to 15 years. Even if there is metastasis, the patient can survive for a long time, except for the esophagus, any of the digestive tract. Carcinoids can occur in the area, and 1/3 in the appendix, more common in women, rarely metastasized. 2% in the stomach, the rest in the duodenum, colon (more common in men), gallbladder and Meckel's diverticulum, can also occur in the bronchi and ovary, but less common.
Cause
Cause
Carcinoid-like cells produce a variety of biologically active substances, the most important of which are serotonin, bradykinin, histamine and prostaglandins. Serotonin is derived from tryptophan in food. Under normal conditions, 99% of tryptophan is utilized by the body to form niacin or nicotinamide, and only 1% is utilized by gastrointestinal mucosal cells to produce serotonin. Serotonin is present in the gastrointestinal mucosa with only a small amount in platelets and brain cells. After carcinogenesis, 60% of the tryptophan in food is converted to serotonin in carcinoid cells, so there is a significant increase in serotonin in the blood of carcinoid patients.
Examine
an examination
Related inspection
Serum sialic acid assay effusion carcinoembryonic antigen erythrocyte enolase
(A) 5-HT determination of serum 5-HT levels in patients with carcinoid syndrome often increased significantly, mostly 83 ~ 510mol / 24h (normally 11 ~ 51mol / 24h).
(B) 5-HIAA determination of urinary 5-HIAA excretion in patients with carcinoid syndrome, often more than 78.5mol / 24h, generally 156.9 ~ 3138mol / 24h (normal value <47.1mol / 24h).
Diagnosis
Differential diagnosis
Need to be identified with the following diseases:
1 Menopause skin flushing: It is a kind of skin flushing that lasts for a long time, but it is not serious, and it has a feeling of fever. No skin purpura, no abdominal pain, diarrhea, wheezing and other symptoms.
2 neuroedema: due to various stimuli, sudden soft tissue limited edema. An allergic angioedema, often occurs in the face, lips, eyelids, can also occur in the mouth and throat, severe edema of the throat can cause asphyxia, but not accompanied by flushing and other carcinoid manifestations.
3 systemic mastocytosis. Due to the increase in histamine production, it causes skin flushing, erythema may appear on the skin and mucous membranes, and there may be urticaria-like changes. Longer duration, diarrhea can occur. When the skin is flushed, histamine in the blood increases.
