Cronkhite-Canada syndrome: also known as polyp, hyperpigmentation, alopecia, and paw nail dystrophy syndrome. Its clinical features are mainly diarrhea, multiple polyps in the whole digestive tract, with skin pigmentation, hair loss, paw nail atrophy, etc.
I. Epidemiology
According to Ishido statistics in 1985, Japan has the highest incidence, followed by North America and Europe. Its geographical distribution is proportional to the population density. The age of onset is 26 to 85 years old, with an average of 61 years old, and about 80% of patients are over 50 years old at the time of first occurrence. There is no difference in the incidence rate between men and women in Europe and the United States, but Japan reports a male to female ratio of 2 or 3:1.
Etiology
The cause of the disease is not known so far. Most patients have triggers, such as mental stimulation, overexertion, long-term medication or surgery.
Total gastrointestinal polyposis may be related to inflammation due to bacterial colonization in the small intestine, lack of delayed immune response, and decreased plasma immunoglobulin IgM values, while immunoglobulin IgA values are normal. Immunofluorescence examination shows a decrease in IgA-producing cells in the small intestine and an increase in IgG-producing cells, which may be associated with bacterial or viral infection. Due to small intestinal disaccharidase deficiency, bacteria can convert carbohydrates that remain in the intestine for a long time into short-chain fatty acids and cause diarrhea due to their osmotic pressure effect.
III. Pathology
Most scholars believe that the polyps of this sign belong to juvenile type misshapen-like polyps. The polyp is covered with epithelial cells, cystically dilated by glandular hyperplasia, and hypersecretory, containing protein-like fluid or mucus. The mucosal lamina propria is vascularly congested, with chronic inflammatory edema and marked eosinophilic infiltration. The polyps can be distributed anywhere in the whole gastrointestinal tract from the esophagus to the rectum.
IV. Classification
According to the pathogenesis of this syndrome, Japanese scholar Ishido classified it into 4 types.
Type I: with diarrhea as the first symptom.
Type II: abnormal taste before the appearance of all symptoms.
Type III: initial symptoms of hair loss and atrophy of the paw nails.
Type IV: loss of appetite and general lethargy, followed by paw nail atrophy, hair loss and abnormal taste, but no diarrhea.
V. Clinical manifestations
1. Gastrointestinal symptoms.
(1) diarrhea: is the most important symptom of the syndrome, 90% of patients can be seen, mostly watery stool, several times a day to more than ten times, a few patients with blood in the stool, most accompanied by abdominal pain. 1/3 patients appear loss of appetite, abnormal taste, easy fatigue, diarrhea occurs only after several days or months, but can be briefly relieved, easy to relapse. There are also a few patients who have only soft stools or no diarrhea.
(2) Abdominal pain: The severity varies, manifesting as pain in the upper or lower abdomen. Many patients may have colic, mostly occurring at the same time as diarrhea, but there are also those with only upper abdominal discomfort and fullness.
(3) Loss of appetite, weight loss, easy fatigue: most patients have this manifestation, and it becomes obvious with the increase of abdominal pain and diarrhea.
(4) abnormal taste, thirst, tongue numbness, etc.: 80% of patients may have loss of taste, thirst, etc. A few patients may have tongue numbness, mental retardation, hand and foot twitching, etc.
2. Skin symptoms.
(1) Hair loss: 90% of patients have hair loss, often generalized, such as hair, eyebrows, beard, axillary hair, pubic hair, extremity hair, etc. can be lost. Most patients have very sparse hair and may even lose all their hair within 2-3 days, usually after the exacerbation of gastrointestinal symptoms such as diarrhea.
(2) Claw nail changes: All patients have claw nail changes. The nail color becomes darker, brown, white, yellow or black, and the surface becomes scaly, uneven or spatulate. The claw nail is fragile and thin, soft and easily cracked, and may be partially or even completely detached from the nail bed. The nail often starts proximally and remains adherent distally, detaching completely after a period of time, leaving a ridged nail bed. The distal part of the new nail remains uneven.
(3) Hyperpigmentation: This is seen in most patients as small nevus-like or light to dark brown spots ranging in size from a few millimeters to 10 cm. It occurs on the palms of the hands, plantars, dorsum of the hands, dorsum of the feet, and the face. In addition to the above-mentioned areas, mottled pigmentation can also be seen on the lips and their surroundings, oral mucosa, perineum, etc.
VI. Examination
1. Blood examination: 88% of patients show hypoproteinemia, with total serum protein below 60,8g/L. In serum electrolytes, potassium, calcium, phosphorus and magnesium are low, but sodium and chloride are within the normal range. A few patients had low blood trace elements of iron, copper and zinc. Most patients had lower than normal blood immunoglobulin IgG and IgM.
2. Digestive absorption test: Half of the patients had impaired absorption as seen in dextrose absorption test, 57 cobalt, and Schlling test of vitamin B12. 131 iodine test, fat absorption test of triglycerides, 70% had impaired absorption. Analysis of gastric juice after histamine stimulation in fasting revealed that most patients had gastric acid deficiency or too little gastric acid.
3.X-ray examination: Barium meal examination of the digestive tract shows multiple nodular or polyp-like filling defects in the stomach, ranging in size from 3 cm to 3 cm. The gastric mucosal folds are widely thickened and sometimes misdiagnosed as Menetrier’s disease, i.e. giant hypertrophic gastritis; the small intestine shows extensive polyp-like filling defects or thick intestinal mucosa, most of which are in the duodenum. In barium enema or dual gas-barium imaging, polyps are widely present in the colon and rectum. Sometimes the polyps are densely clustered so that no normal mucosa is visible in the colorectal lumen.
VII. Diagnosis
The main points of diagnosis are.
1, the onset is mostly in middle-aged and elderly people.
2, the main symptoms are diarrhea, abnormal claw nails, hair loss, hyperpigmentation, abnormal taste, etc.
3, characterized by gastrointestinal and colorectal polyposis mainly.
4, pathological biopsy shows that the polyp has epithelial cell coverage, glandular hyperplasia with cystic expansion, intercellular edema and visible inflammatory cell infiltration.
5.Protein leakage test is abnormal, mostly with hypoproteinemia.
VIII. Treatment
1, medical treatment: generally take symptomatic therapy, nutritional therapy, the use of antibiotics, glucocorticoids, anabolic hormones and antifibrinolytic enzymes, can also use plasma products. In recent years, some people have applied anti-inflammatory treatment with salazosulfapyridine. Japanese scholars are using high-energy therapy, which has achieved certain results.
2, surgical treatment: rectosigmoid polyps, can be removed by anal ligation or electrocoagulation. If cancer is found or the systemic consumption is serious or complications of intussusception, colon and rectal resection can be done.