hookworm
Introduction
Introduction to hookworm disease Hookworm disease (ancylostomiasis) is a disease caused by parasitic nematodes of the duodenum or H. elegans (also referred to as hookworm) in the small intestine. When the human body is exposed to the infectious larvae (filamentous mites) of the hookworm, the larvae penetrate into the skin and cause infection. Clinically, anemia, malnutrition, and gastrointestinal dysfunction are the main manifestations, and severe cases can cause developmental disorders and cardiac insufficiency. basic knowledge The proportion of illness: 0.052% Susceptible people: no specific population Mode of infection: fecal mouth spread Complications: gastrointestinal bleeding
Cause
Cause of hookworm
Hookworm infection (95%):
It is mainly a hookworm of the duodenal nematode or the American hookworm, which mainly causes lesions in the skin, small intestine and lung.
Dermatitis: Crohn's dermatitis shows local vasodilation, hemorrhage, and serum exudation. There are neutrophils, eosinophils, monocytes, and fibroblasts infiltrated in the dermis, and larvae are sometimes seen in connective tissues, lymphatic vessels, and blood vessels.
Small intestine: Adult hookworms are adsorbed on the villus of the small intestine by the oral sac, causing most bleeding spots and small ulcers. Commonly known as scattered, 3 ~ 5mm shallow hemorrhage or erosion, followed by large block deep and submucosal or even muscular hemorrhagic fistula. There are often edema and neutral, eosinophil and lymphocyte infiltration in the mucosal, lamina propria and submucosa around the ulcer.
Lung: a bit of hemorrhage in the lung tissue, infiltration of neutrophils, eosinophils, monocytes, and fibroblasts. If there is a large amount of sputum migration, it can cause extensive inflammation of the lung tissue, and even form lobular consolidation.
Pathogenesis
1. The pathogenic role of larvae: larvae invade human skin can cause hooky dermatitis, and small red papules can appear on local skin.
2. Adult-induced damage: Adult hookworms are adsorbed by the oral sac on the villus of the small intestine to feed on the mucosal epithelium and blood. Adults often change the adsorption site and secrete anticoagulant substances, so the mucosa adsorbed by hookworms continuously oozes blood, causing chronic blood loss and plasma protein loss.
Pathological changes : pathological changes mainly occur in skin, lung tissue, intestinal tissue and so on.
Prevention
Hookworm disease prevention
1. Management of infectious sources: In the epidemic areas, the census is treated every winter.
2. Cut off the transmission route: strengthen the management of manure, pay attention to the harmless treatment of feces, prohibit the fertilization of fresh manure, use high-temperature composting method, or kill the eggs in the feces with drugs, which is the key measure to prevent this disease. Vegetables to prevent hookworms from being infected by mouth.
3. Protect susceptible populations: Avoid avoiding bare hands and feet when working in a susceptible environment; in addition, apply protective drugs on the skin, which also has certain effects. Protective drugs can be prepared as follows: white peony, 1% iodine Wine, 95% ethanol 100ml, soak for l ~ 2 days, filtered, add ethanol l00ml, rosin 15g, recently applied the following formula of rosin ethanol, the protective effect is considered to be more reliable: 95% ethanol 1000ml, add rosin 200g, take potassium iodide 20 g, dissolved in 20 ml of distilled water, and then added 20 g of iodine tablets, dissolved, added to the above rosin ethanol, shaken and prepared, and coated on the skin to be exposed.
Complication
Hookworm disease complications Complications, gastrointestinal bleeding
Hook dermatitis, gastrointestinal bleeding.
Symptom
Hookworm disease symptoms Common symptoms Abdominal discomfort Abdominal pain, spotted hemorrhage, or can be found in filamentous hernias, dyspepsia, diarrhea, nausea, tinnitus
Symptoms caused by larvae
(1) Hook dermatitis: It is the most common early clinical symptom of hookworm infection. A few minutes after the filamentous mites invade the skin, the skin may experience burning, acupuncture or itching, followed by hemorrhagic small spots and papules, which become blisters after 1 to 2 days. Local symptoms disappeared within 3 to 5 days and healed.
(2) Respiratory symptoms: 3 to 7 days after the filamentous mites invade the skin, the larvae migrate to the alveoli with the blood flow. If the amount is high, respiratory symptoms such as itching, cough, and cough may occur. In severe cases, severe dry cough and asthma may occur. Attack, manifested as eosinophilic asthma; sometimes can have chills, fever and other manifestations. X-ray examination showed an increase in lung texture or hyperplasia of the hilar, and occasionally a transient pulmonary invasive lesion was found.
(3) Acute hookworm disease: refers to the early hookworm syndrome caused by a large number of hookworm infections in a short period of time. Clinical manifestations In addition to the above-mentioned skin and lung damage, some patients may have obvious gastrointestinal symptoms 1 to 2 weeks after the appearance of respiratory symptoms, such as abdominal pain (mostly umbilical or upper abdominal pain) and diarrhea (watery stool) the Lord). In addition, there may be fever, loss of appetite, and general weakness.
Symptoms caused by adults
(1) Symptoms of the digestive system: Most patients gradually develop upper abdominal discomfort or pain, loss of appetite, diarrhea, fatigue, weight loss, etc. 1 to 2 months after infection.
(2) symptoms of anemia: progressive anemia gradually appeared 3 to 5 months after severe infection, manifested as dizziness, tinnitus, palpitations, shortness of breath and so on. Long-term severe anemia can cause heart disease, which is characterized by enlarged heart and increased heart rate. Severe anemia is often accompanied by hypoproteinemia and lower extremity or systemic edema.
Examine
Hookworm disease check
1. If the worm is found, it can be sent directly for inspection.
2. Examination of fecal eggs.
3. The occult blood test can be positive.
4. Blood: There are often different degrees of anemia, belonging to small cell hypochromic anemia. It is an increase in acid granulocytes.
5. X-ray examination: There may be an increase in lung texture, scattered in the flaky shadow, and the interstitial structure of the lung is changed.
Diagnosis
Diagnosis and identification of hookworm disease
Diagnostic criteria
1. Clinical diagnosis: In the epidemic area of hookworm disease, there may be contact history, hook dermatitis and anemia of mild and severe, malnutrition, gastrointestinal dysfunction, upper abdominal pain and so on.
2. Etiological diagnosis: Pathogens must be found in order to diagnose hookworm disease.
(1) Egg inspection: Take the stool and use the direct coating method to find the eggs under the microscope. The detection rate is low, and it can be done several times.
(2) Identification of adults: If the worms are found, they can be placed in 70% ethanol for identification.
Differential diagnosis
The typical diagnosis of hookworm infection is not difficult, but it should be caused by other causes of dermatitis, iron deficiency anemia, chronic blood loss anemia such as ulcer disease, stomach cancer, hemorrhoids, etc., and other causes of anemia such as aplastic anemia, Identification of hemolytic anemia, pernicious anemia, etc.
