Overview
Pulmonary hookworm disease is a parasitic infection. It is caused by the invasion of hookworm filarial larvae through the skin or mucous membranes. Farm work is an important source of infection. The main manifestations of contact with pollutants often appear on the hands and feet of small bleeding spots, papules, small herpes, very itchy, that is, hookworm dermatitis, or low-grade fever, itchy throat, pain, dry cough with blood in the sputum, or even hemoptysis.
Hookworm filarial larvae through the skin or mucous membrane invasion of the human body, through the lymphatic or blood channels to the lungs, and penetrate the pulmonary capillaries into the alveoli, causing punctate hemorrhagic inflammatory cell infiltration of the lung pathology is similar to the pulmonary ascariasis, severe infections can be formed in the lung lobular solid changes and bronchitis.
Pathogenesis
Hookworm eggs develop into infective filamentous larvae through decidualization and invade the human body from the skin and mucous membranes, and farmland operation is an important source of infection. Hookworm disease is prevalent in almost all rural areas of China except the Tibetan plateau area, and the hookworm infection rate is generally 5% to 30%.
Symptoms
Patients exposed to pollutants on the hands and feet often appear small bleeding spots, papules, small herpes, very itchy, that is, hookworm dermatitis, or low-grade fever, pharyngeal itching, pain, dry cough, blood in the sputum, or even hemoptysis, and some patients may have a transient shortness of breath, chest tightness, wheezing, and other symptoms of asthma-like episodes. Physical examination may show scattered dry or wet rales.
Examination
1. Laboratory examination
Examination of peripheral blood leukocyte count is increased or even leukemia-like reaction, eosinophil count is mildly to moderately increased. Filamentous larvae may be found in sputum examination.
2. Other auxiliary tests
X-ray chest film may show blurred or enlarged hilar shadows, increased lung texture, lamellar or nodular shadows, etc. Lung X-ray manifestations mostly disappear in half to one month.
Diagnosis
In endemic areas, there is a history of barefoot field and fecal toxicity, clinical anemia, cough and other manifestations should be suspected of hookworm disease, through the fecal examination can be clearly diagnosed.
Treatment
1. Hookworm dermatitis
Available 2% ~ 4% iodine, 15% thiabendazole ointment or suspension plus 0.1% dexamethasone local application.
2. Drug deworming treatment can be used
(1) Albendazole (intestinal worms) Selectively and irreversibly inhibit glucose uptake of intestinal nematodes, so that the endogenous glycogen depletion of worms, and inhibit the enzyme of fenugreek reductase to hinder the production of ATP, resulting in the death of the worms. This drug is well absorbed after oral administration, the dosage is reduced by half for children under 12 years old, and is contraindicated in pregnant and lactating women, and used with caution in those with a history of epilepsy.
(2) Levamisole The anthelmintic activity of this product is 2 times that of tetramisole, and it selectively inhibits the succinate dehydrogenase of the muscle of the worms, paralyzing the worms and discharging them with intestinal peristalsis.
(3) Obendazole This drug has few adverse reactions.
Prevention
Focus on strengthening hygiene publicity, promoting the harmless treatment of feces, reforming fertilizer application and farming methods, and conducting regular census and general treatment in endemic areas.