What examination should be done for gangrene?

summary

Anthrax belongs to zoonosis, and its pathogen is gram-negative Pseudomonas mallei. People are very susceptible to gangrene, mainly caused by contact with infected animals. Its symptoms are the formation of specific gangrenous nodules, ulcers or scars in the nasal cavity, larynx, tracheal mucosa or skin, and the formation of gangrenous nodules in the lung, lymph nodes or other substantive organs. It can be diagnosed by etiology and serology. What examination should be done for gangrene?

What examination should be done for gangrene?

The average length is 2-5um and the width is 0.5-1.0um. It does not form spores and capsules, has no flagella, can not move, and has no active biochemical reaction. There are two kinds of antigens of Bacillus pseudomallei, one is specific antigen, the other is cross reactive antigen with Bacillus pseudomallei. Its endotoxin has a kind of protein that causes allergic reaction, which is called anthraquinone.

In the examination of pus or secretion smears, after the skin pus or nasal secretion smears were removed and stained with methylene blue, Giemsa, Rett, etc., two poles of highly stained bacteria could be seen, but Burkholderia pseudomallei staining was also positive, so this method could not distinguish Burkholderia pseudomallei from Burkholderia pseudomallei.

Immunoassay showed that serum could be used for hemagglutination and complement binding test. Hemagglutination test had high sensitivity, and its titer was more than 1 ∶ 640. Complement binding test had strong specificity, but it was difficult to operate, and its titer was more than 1 ∶ 20. At present, the simple solid-phase complement binding test has been used in the examination. If the diameter difference of hemolytic ring between the control hole and the test hole is more than 6 mm, it is judged as positive.

matters needing attention

The clinical manifestations of gangrene are complex and difficult to diagnose. The epidemiological history of contact with sick horses or treatment of pathogenic bacteria in the laboratory, secretion, puncture fluid and blood culture, serological examination (hemagglutination and solid phase complement binding test), intradermal test of anthrax, inoculation of infected guinea pigs, etc. are helpful for the diagnosis of the disease.